Thursday, April 29, 2010
In 1986, Southwest Airlines was only the 14th largest airline in the United States and had only 63 aircraft in its fleet. In fact, in terms of passengers carried, Southwest was less than one-tenth the size of United Airlines. But from the passage of the Airline Deregulation Act in 1978, Southwest had not only grown four-fold but had remained consistently profitable during the rocky early years of deregulation. But few Americans at the time had heart of Southwest Airlines as it was still for the most part operating in Texas and the adjacent states. Despite its relative obscurity, though, the business world from academia to other industries took a close look at Southwest trying to divine the secret to its success. Perhaps Robert Crandall, the iconic head of American Airlines, Southwest's main competition in the Dallas/Fort Worth market, said it best when he said "That place runs on Herb Kelleher's bullshit."
The compromise that left Southwest at Dallas Love Field, the Wright Amendment, only applied to Southwest's services from Dallas and limited those services to the adjacent states of New Mexico, Oklahoma, Arkansas, and Louisiana. But there were no such restrictions on Southwest's other services from other cities in its network and when Kelleher ended up running Southwest full time in 1981, he was ready to break out and head west as well as east.
The only problem was that in the wake of the 1981 PATCO strike, the lack of replacement air traffic controllers led to the imposition of slots at the major airports in California that Kelleher wanted to start serving. Until staffing levels were restored, traffic would be restricted at these key airports but that a certain portion of the slots created were to be assigned to new entrants. Kelleher's legal background helped him as he read up on the minutiae of the slot assignment rules. Since Southwest had been operating since 1971, it was hardly a new entrant, but the airline did have a subsidiary set up called Midway Southwest that dated back to the airline's earlier days. Midway Southwest was originally set up to start services to Chicago Midway, but the plans back in the airline's nascent days never got off the ground.
So Kelleher applied for the new entrant slots as Midway Southwest, to his surprise got them from the FAA, and then traded them to Southwest Airlines. Someone higher up in the FAA figured out Kelleher's ruse and struck down the slot award- slots, said the FAA, could only be traded by operating airlines. Ever resourceful and not taking no for an answer, Kelleher then sold Midway Southwest to a charter company that owned a single Learjet. The charter company then traded the slots to Southwest and since the rules as written by the FAA for new entrant slot awards didn't specify charter vs. scheduled let alone a minimum fleet size, the FAA was unable to nullify the slot award a second time. Southwest got its slots to Los Angeles International Airport and prepared to inaugurate services to LAX via Phoenix, Arizona.
All was good and well until the FAA Administrator, J. Lynn Helms (I mentioned him in yesterday's posting on ETOPS and the Boeing 767) found out about Kelleher's legal maneuverings to get access to LAX. Helms summoned him to Washington immediately to explain himself. Helms berated Kelleher for making a mockery of the system by using loopholes in the rules to gain slots to LAX. After his tirade, Helms smiled and confessed that he enjoyed Kelleher's legal maneuvers to win the slots. The story as it's been told is that Helms then ordered Kelleher to leave his office and act as if he'd had his heart ripped out.
So along with services to California, Southwest added Las Vegas, Kansas City, and St. Louis (all now key cities in Southwest's network) and in 1985 the airline opened its services east of the Mississippi River to Chicago Midway. And the rest, they say, is history!
Source: Hard Landing: The Epic Contest for Power and Profits That Plunged the Airlines into Chaos by Thomas Petzinger, Jr. Three Rivers Press, 1996, p320-321.
Wednesday, April 28, 2010
Federal Aviation Regulation (FAR) 121.161 states "Unless authorized by the administrator, based on the character of the terrain, the kind of operation, or the performance of the airplane to be used, no certificate holder may operate two-engine airplanes over a route that contains a point farther than 1 hour flying time (in still air at normal cruising speed with one engine inoperative) from an adequate airport." The rule was written in the days of the propliner when piston engines didn't have the reliability of modern jet turbines. When the Boeing 767-200ER entered service, it was the first commercial twin-jet capable of crossing the oceans- when Boeing's director of engineering, Dick Taylor, first approached FAA administrator Lyn Helms in 1980, Helms responded "It'll be a cold day in hell before I let twins fly long haul, overwater routes."
In 1980 three- and four-engined aircraft handled all the long range routes, particularly those that were overwater. There was a joke that stated "The reason I fly four-engined aircraft across the ocean is because there are no five-engined aircraft." But modern technology and computerized systems brought to the Boeing 767 a level of redundancy, safety, and efficiency not seen in any prior commercial aircraft. And it wasn't just the reliability of the engines, the various systems of the 767 facilitated the development of ETOPS- Extended-range Twin-engine Operational Performance Standards- the ability of a twin engine jetliner to exceed the old 60-minute rule.
For two years Boeing collected reams of data on the first 767 operations, compiling information on every shutdown and failure of any system including the engines in the first two years of commercial airline services. In April 1984 El Al Israel Airlines became the first airline to operate the 767 on trans-Atlantic services between Montreal and Tel Aviv, but the aircraft's routing complied with the 60-minute rule. Not long after, El Al, Air Canada, and Trans World Airlines (TWA) received exemptions to operate no more than 75 minutes from a suitable diversion airport. This would open up some trans-Atlantic routes and Caribbean routes to the 767. In fact, Air Canada was the first to crack the 60-minute barrier having earned its 75-minute exemption in late 1983.
In June 1984 Boeing showcased the new 767-200ER's long legs with a 7,500 mile delivery flight from Washington Dulles to Addis Adaba, Ethiopia to bring the 767 to Ethiopian Airlines. The flight required a special one-time FAA waiver to take place. In October 1984 Air Canada took delivery of the first ETOPS-qualified 767-200ER which was permitted to go 75 minutes from a suitable diversion airport. The International Civil Aviation Organization (ICAO), the International Federation of Air Line Pilots Association, the US-based pilots' union Air Line Pilots Association (ALPA) and the FAA made several recommendations to Boeing that resulted in the 767-200ER having a fourth electrical generator independently powered by a hydraulic motor, additional fire suppression features and equipment for cooling of the CRT displays in the cockpit.
By 1985 Dick Taylor at Boeing was lobbying the FAA hard for extension of the 75-minute rule to 120 minutes which would open up a large number of trans-Atlantic routes to the 767. Already several airlines led by TWA had petitioned the FAA for an ETOPS extension to 120 minutes but before the FAA would grant the extension, Boeing had to show "statistical maturity" by equipping a number of 767s with special data gathering equipment to show unparalleled standards of inflight reliability and the Pratt & Whitney JT9D engines had to log 250,000 consecutive flight hours on passenger flights with a very low rate of shutdown.
On 1 February 1985, TWA Flight 810 departed Boston for Paris on the first revenue passenger flight in history under the 120-minute ETOPS rule. The new ETOPS rule shortened the flight distance and it would replace a Lockheed L-1011 Tristar that normally served the route. Before Flight 810 departed, sixteen TWA pilots went through specialized ETOPS training on international requirements, intensive time in a simulator and landing procedures for the airport at Sondrestromfjord in Greenland, the designated 120-minute diversion airport. Eleven observers from the FAA were aboard TWA 810 and the fuel burn was found to be 7,000 lbs an hour less than that of the L-1011 Tristar on the same route. TWA was so convinced of the efficiency of the 767 with the 120-minute ETOPS rule that it spent $2.6 million per aircraft retrofitting all of its 767-200s for 120-minute ETOPS compliance.
But Boeing and Dick Taylor didn't stop there. The existing 120-minute ETOPS rule wasn't enough to get the 767 to Hawaii from California. But Boeing continued to compile failure and shutdown data on the 767 on the trans-Atlantic route to prove the the FAA that it was possible to safely operate the 767 to Hawaii from the US mainland. In 1989, the FAA approved the ETOPS extension to 180 minutes which opened up Hawaii to the 767, as the halfway point between Hawaii and the US mainland is approximately 150 minutes' flying time. But to gain the 180-minute extension, a particular aircraft and engine combination had to show 12 consecutive months of 120-minute ETOPS flights and meet stringent engine failure rates. By 1993 the entire 767 family, both the -200 and the -300, as well as the possible engine options of GE, Pratt & Whitney, and Rolls-Royce, gained full 180-minute ETOPS extensions.
By 1991 the number of passengers crossing the Atlantic on 767s exceeded the number of passengers crossing on three- and four-engined aircraft for the first time in history. By 2000, over 50% of all trans-Atlantic crossings were being made by the 767 family of aircraft. By that time, all brand new 767s rolling out at Boeing's factory in Everett were certified for 180 minutes ETOPS extensions.
It will be the legacy of the Boeing 767 to show that any place in the world could be crossed safely and efficiently with only two engines and it set the stage for the arrival of the Boeing 777 and Airbus A330 family of aircraft that routinely fly routes today that were once the exclusive domain of multi-engined aircraft like the Boeing 747, A340, DC-10/MD-11 and L-1011 Tristar.
Source: Boeing 757 and 767 (Crowood Aviation Series) by Thomas Becher. The Crowood Press, 1999, p145-155.
Monday, April 26, 2010
For the first ten days of the 1973 Yom Kippur War, the Egyptians held the clear advantage in the Sinai having crossed the Suez Canal on the first day of the war on October 6. The massed Egyptian formations that were firmly established on the east bank of the Suez Canal were protected from attack by Israeli warplanes by a dense network of SA-2 "Guideline" SAM sites on the Egyptian side of the canal. Combined with an overwhelming advantage in tanks and soldiers armed with anti-tank weapons, it was not until the Syrian offensive into the Golan Heights had been repulsed and pushed back into Syria that the tide began to turn in favor of the Israelis.
In the middle of the night on October 16, an Israeli paratroop brigade under the command of Colonel Danny Matt crossed on the west bank of the Suez, establishing a bridgehead for follow on Israeli forces to push into the Egyptian rear. Already two Egyptian armored divisions had crossed the canal to supplement the large forces established nearly along the entire length of the east bank of the Suez. Prepared to engage Egyptian armored units, Matt's brigade carried over 300 LAW missiles as well as bazookas and recoiless rifles until sufficient Israeli tanks could cross the canal to provide support. Through the night, however, Gilowa wheeled ferries were used to carry Major Giora Lev and his fourteen Centurion tanks to the Egyptian bank of the Suez along with a company of infantry M113 armored personnel carriers.
After an initial raid led by Major Lev against an Egyptian supply depot housed in a former airfield, he was contacted by General Haim Bar-Lev, commander of the southern front in the war. Bar-Lev gave him a most unusual order:
"I'm putting you under the command of the air force commander." Tanks? Under command of the Israeli Air Force? The chief of the Heyl Ha'Avir, (Israeli Air Force), General Benny Peled, then came over the radio with an even more unusual order:
"Do you see the flowers on your map?"
"Do you see numbers in red?" Next to each was what Major Lev thought looked like a daisy.
"Yes, I see them."
"Destroy all those in your area. Out."
Lev assigned his brigade commander, Haim Erez, to take a force of 21 tanks to destroy the "flowers". Erez was just as mystified as Lev as the significance of the flower markings on their maps. Destroying several small Egyptian units, missile transporters and supply columns on the way, Erez's tanks came upon the first site which turned out to be an SA-2 missile site, one of several in his sector that provided a protective umbrella over the Egyptian bridgeheads in the Sinai. A reservist with Erez was an engineering student and explained that the "flowers" were the distinctive six-pointed layouts of the SA-2 launchers with the control equipment and radars in the center. On a sixty-mile run from Colonel Matt's bridgehead that brought Erez's force within 30 miles of Cairo and back, they had destroyed enough SA-2 sites to create a hole in the SAM umbrella that would soon be fully exploited to turn the tide of the war in Israel's favor.
It marks the only time thus far in military aviation history that tanks were used in the role of the suppression and destruction of enemy air defenses, a role traditionally carried out by specialized aircraft (like the USAF's Wild Weasels) or specialized missiles (like the Shrike or the Standard ARM).
Source: The Yom Kippur War: The Epic Encounter That Transformed the Middle East by Abraham Rabinovich. Schoken Books/Random House, 2004, p386-391.
Thursday, April 22, 2010
It was a moment that not even Boeing, Douglas, or Lockheed could have envisioned taking place. In June 1955 in one of Capital Airlines' hangars at Washington National Airport, Patricia Nixon, wife of the US vice-president Richard Nixon, christened Capital's first Vickers Viscount, N7402 as Capital's president, Slim Carmichael and an enthusiastic crowd of dignitaries and employees looked on. In 1955 Capital was already an industry leader despite being only the fifth largest airline in the United States. It was the first airline to introduce low-fare no-frills services to the United States with its nightly "Air Coach" services that started in 1947, flying aircraft that otherwise would have sat unused at night waiting for the daytime regular full-fare services.
The introduction of the Viscount on Capital's network on 26 July 1955 between Washington DC and Chicago marked the first US scheduled turbine passenger services and it was on an aircraft that wasn't built in Seattle, Long Beach, or Burbank. Vickers pulled off a sensational coup with the Capital sale and at the time, the order for sixty Viscounts represented the largest single post-war dollar sale for Great Britain, worth $67 million. BEA was even talked into giving three early delivery spots to allow Capital to the first to operate turbine services in the United States with the Viscount. BEA and Vickers invested heavily in getting Capital prepared to operate the Viscount.
Fortunately for Vickers, the changes needed to get US certification for the Viscount had already been accomplished in getting the order for Trans-Canada Airlines the year before. While there were still modifications needed to meet US certification and Capital's own requirements, the majority of the work had already been done to meet TCA's requirements and that of Canadian certification.
But it would all come crashing down for Capital only six years later. Three factors would lead Capital to financial ruin and eventual merger with United Air Lines in 1961, but none of them were attributable (contrary to popular belief) to the performance of the Viscount itself. The first one was that Capital's route network consisted of many smaller communities and routes that were too short to be economical for the Viscount. Secondly, increasing competition from airlines like United that were introducing pure jets on the same longer range routes that were ideal for Capital's Viscounts resulted in their planes being flown faster to try to match the block times of the jets. As a result, maintenance costs on the aircraft and particularly the engines, increased dramatically as the aircraft were being pushed harder. Adding to the airline's woes were the crashes of four Viscounts between 1958 and 1960 that brought press attention to the airline's problems.
By 1960 Capital owed Vickers $34 million in outstanding payments on the Viscounts and they had to go to US court to file suit. Vickers was persuaded to take back 15 of the Viscounts while Capital came up with a restructuring plan that centered around ordering modern jet equipment in the form of the De Havilland Comet 4B while they successfully petitioned the Civil Aeronautics Board to gain more nonstop route authorities in their network and drop some of the more unprofitable destinations.
Unfortunately it was too little too late as Capital's large 1954 order for sixty Viscounts resulted in increasing interest payments that left the airline little financial flexibility. However, stoked by the press, the general public gained the impression that it was the Viscount itself that was causing Capital's problems when in fact their Viscounts were operating at an 80 percent load factor compared to 58% for the other types in the fleet. Break even on the Viscount for Capital was only 52%, so the aircraft was clearly a money maker for Capital, but it wasn't enough to stave off the large growing debt obligations from the large sixty aircraft order. On 1 July 1961 Capital's operations were merged into that of United Air Lines, but in a show of the aircraft's soundness, United retained the Viscounts in its fleet and even recalled some of the aircraft that Capital had returned to Vickers.
Source: Vickers Viscount and Vanguard by Malcolm L. Hill. Crowood Press Ltd, 2004, p40-48, 97-99.
Wednesday, April 21, 2010
During times of war, operational necessities sometimes breed unusual solutions- in the Second World War the most famous of these was the Japanese kamikaze. Though no Allied airmen were ever committed to a formal suicide mission, the desperation of the in its first half did lead to one program that probably comes as close as can be to a suicide mission- the Catapult Armed Merchantmen (CAM ) ship program put in service by the British during the early days of the Battle of the Atlantic.
Being an island nation, Great Britain was dependent upon maritime trade and in particular, dependent upon the Atlantic convoys from the United States that delivered not just weapons and armaments, but also food staples and fuel. As the Battle of the Atlantic intensified in 1941, the German U-boat menace began taking its toll on merchant shipping that was Britain's wartime lifeline. However, the U-boats were only part of the problem as the Luftwaffe's long-range Focke Wulf Fw 200 Condor long range patrol bombers also preyed on the convoys and also provided eyes for the submerged U-boat wolfpacks.
The solution was the Catapult Armed Merchantmen and the Hawker Sea Hurricane. Approximately 36 cargo ships were fitted with a rocket-driven catapult mounted on the forecastle of the ships. The catapult was mounted in a fore-aft orientation and slightly offset to port to which the Sea Hurricane was mounted. The first Sea Hurricane variants only had local reinforcements and attachment points to the catapult trolley. Two pilots were assigned to each CAM ship and alternated 12 hour shifts. Once a Condor had been sighted, the alert pilot strapped into the Sea Hurricane and the rocket catapult fired, moving the Sea Hurricane and the expendable trolley at 3.5Gs while the pilot had the engine running at full power.
The CAM ship's forward structures were shielded to prevent damage caused by the rocket blast. Once committed to launch, the pilot had to use 1/3 starboard rudder to overcome the Hurricane's tendency to swing to port at full throttle. In addition, 1/3 flap was used to help get the Sea Hurricane airborne with the trim tabs set to neutral. If too much back pressure got applied during launch, the plane would stall and fall into the sea, so pilots would brace their right arm by shoving their right elbow against their hip to prevent inadvertent back pressure from the G-forces of the launch.
Launching the Sea Hurricane and engaging the Condor was the easy part of the mission. Since there was no way of returning to the ship, the pilot only had two choices- either ditch near the ship or hope there was enough fuel to head for land. Ditching a Sea Hurricane wasn't a great option- the bottom mounted radiator scoop easily flooded and the aircraft would sink quickly. If land was too far away to reach, the preferred option was to bail out rather than ditch the aircraft. Timing was of the essence, as exposure in the cold North Atlantic required an expeditious rescue out of the water. Later versions of the Sea Hurricane were fitted with two 44-gallon underwing tanks to extend the range and make reaching land more feasible.
As a result of the risks to the pilot in launching the Sea Hurricane, it was considered a last resort as most convoy captains didn't want the rocket flash to attract the attention of the Condors. By 1943, though, the CAM ships and their risky missions were superseded by the arrival of the first small escort carriers called MACs- Merchant Aircraft Carriers. The MACs were small escort carriers that lacked any hangar facilities and carried its Sea Hurricane complement (usually five) on the deck exposed to the elements. As a result, the Sea Hurricanes were only good for about 30 flying hours before saltwater corrosion took its toll. Although Sea Hurricanes were also deployed on the larger fleet carriers of the Royal Navy, handing idiosyncrasies on landing made them quickly superseded by purpose-built carrier fighters.
Source: Aeroplane Monthly, April 2010, Volume 38, No. 4. "Fierce Wind over the Deck" by Philip Jarrett, p36-40.
Monday, April 19, 2010
Although the role of the Lockheed C-130 Hercules in Vietnam was primarily that of airlift, one of the most common non-airlift roles it flew was that of a bomber- dropping the large, 15,000-lb BLU-82/B "Big Blue 82" bombs. Following the end of the Second World War the United States did have some bombs in the 10,000-lb class and higher which were dropped by Convair B-36 Peacemaker. They weren't extensively deployed, let alone used, as the B-36's primary mission in the 1950s was that of nuclear deterrence. As the war in Vietnam intensified, the Air Force Systems Command returned to the idea of a large air dropped bomb not as a weapon, but as a rapid combat engineering tool to clear out a helicopter landing zone in the jungle. The B-36 was no longer in service and the B-52's pylons and bomb bay systems weren't designed for the type of weapon the AFSC was considering. One option looked at using the Army's Sikorsky CH-54 Tarhe skycrane helicopters, but the choice eventually settled on the C-130 Hercules due to its speed and range over the CH-54.
The project was designated Commando Vault with the first test drops being conducted in October 1968. The first Commando Vault bombs were the smaller M121 series which weighed in at 10,000 lbs. They were filled with what was called GSX- gelled slurry explosive, a mix of ammonium nitrate, aluminum powder and a liquid gelling agent. GSXs were standard explosives in the mining industry. They were cheap and easily handled, mixed prior to each mission as the mixture tended to be come unstable with time. There is a big misconception that these bombs were fuel-air explosive weapons and they weren't for the simple reason that GSX is a completely inappropriate explosive for FAE applications as it had the consistency of mud and couldn't be aerosolized for an FAE weapon.
The first combat drops were made in Vietnam in March 1969 from the C-130 Hercules. The bomb was carried on a pallet-mounted cradle in the cargo hold and an extraction parachute pulled the load out the rear ramp. The bomb then separated from the cradle and it's own parachute deployed to stabilize it. An extended fuse probe nicknamed the "Daisy Cutter" triggered the bomb before it hit the ground, thereby clearing the trees but not leaving a crater which would preclude the use of the site as a helicopter landing zone. In 1970 a larger version was put into use, this one designated BLU-82/B and it weighed in at 6.8 tons and was about 80% explosive by weight. Also filled with GSX, the BLU-82/B was also dropped by the C-130 and also had a 4-foot stand-off fuse probe that for whatever reason, got the bomb the nickname "Daisy Cutter" when in fact the term "Daisy Cutter" referred to any extended nose probe fuse used on bombs during the conflict.
Accurate drop of the Commando Vault weapons required precise navigation and some of the drops in Vietnam were made using radar guidance as well as the MSQ-77 Combat Skyspot beacon guidance method that was also used to control the B-52 Arc Light drops over South Vietnam. One minute before the drop, the extraction parachute on the cradle of the bomb was deployed into the airstream out the open ramp while the pallet was restrained by the locks in the cargo rails in the C-130's cargo hold. At the release point- usually from a navigator on the flight deck or a ground radar beacon operator in the case of Combat Skyspot- the loadmaster released the locks, dropping the weapon. This also had the unique distinction of making the Commando Vault loadmasters the only enlisted men in Vietnam to deploy aerial weapons!
The minimum altitude for a drop was about 6,000 to 7,000 feet and even at that height, it wasn't unusual for the Hercules to be buffeted by the shockwave of the explosion. In Vietnam, about 200 of the smaller M121 bombs were dropped and about 250 of the larger BLU-82/Bs were dropped. In Desert Storm, the BLU-82/Bs saw action again as being very useful for clearing out large swathes of desert where the Iraqis had placed minefields to stall the Coalition advance. They were also a useful psychological weapon that were typically accompanied by leaflet drops on Iraqi units in the area. On the first night of the ground offensive, the first BLU-82/B drop was mistaken for a tactical nuclear weapon by some of the Coalition units in the area! Eleven BLU-82/Bs were dropped during Desert Storm.
The BLU-82/B was used again in Operation Enduring Freedom in Afghanistan, approximately 3-4 of them being used to hit some of the cave complexes where the Tailban forces were holding out. The last BLU-82/B drop was a test drop in Utah in 2008, the bomb having been since replaced by the more accurate MOAB- GBU-43/B Massive Ordnance Air Blast weapon, also deployed by the C-130 Hercules.
Source: C-130 Hercules: Tactical Airlift Missions, 1956-1975 by Sam McGowan. Aero Publishers, 1988, p124-128.
Saturday, April 17, 2010
The development of the BAe Sea Harrier FRS.1 and the ski-jump are closely intertwined and the discussion one almost always leads to the discussion of the other. Hawker-Siddeley Aircraft, one of BAe's predecessor companies, had studied a naval Harrier variant as far back as 1969 as the P.1184 Maritime Harrier. When the Royal Navy awarded HSA a contract for naval Harrier variant in 1972, financial austerity was the watch word of the day in the British government and though based in part on the P.1184 Maritime Harrier, what would become the Sea Harrier FRS.1 would be a far less radical departure and minimum-change version of the land-based RAF Harrier GR.1.
In 1973 Royal Navy Lt. Commander David Taylor first formulated the ski-jump concept for V/STOL aircraft in the same class as the Harrier. His work was further developed in cooperation with the Hawker's Kingston division and the Ministry of Defence in sophisticated computer models followed by actual flight testing with an adjustable ski-jump built by HSA at the Royal Aircraft Establishment's main testing facility at Bedford.
One of the ski-jump's biggest proponents was John Farley, HSA's chief test pilot for the Harrier and Sea Harrier programs. During his test flights with early Harrier GR.1s off the aircraft carrier HMS Hermes, he found that there were certain moments in the pitching and heaving of a carrier deck in rough seas that could play havoc with a fully-loaded Sea Harrier making an STOL run off the carrier deck. In fact, tests had shown that in some sea conditions, as little as 5 degrees of deck angle up or down either at the stern or bow could shut down flight operations completely.
Farley also noted that in a pitching carrier deck, the most stable point to land in VTOL mode was the center of the deck as the ship virtually pivoted about that point in rough seas. Ideally, a fully-loaded Sea Harrier without a ski-jump would need the full-length of the deck to take off, but this meant that launching and recovery flight operations couldn't be simultaneously undertaken. Testing with the ground-based ski-jump at RAE Bedford showed that a shorter takeoff run would be needed, allowing the forward half of the deck to be used for launching aircraft off the ski-jump and from the midpoint back used for recovery of Sea Harriers.
Farley himself made the first takeoff from the ski-jump at RAE Bedford on 5 August 1977 with the sixth production Harrier GR.1. The first series of tests had the ramp set at 6 degrees, then moved it up to 12 degrees and then finally to 20 degrees. With the ramp at its steepest 20 degree setting, Farley could get a Harrier airborne with as little as 42 knots of airspeed as the ramp provided a significant upward velocity vector that allowed the pilot time to pivot the nozzles back, clean up the aircraft and depart in nearly all but the worst sea conditions. In addition, should an emergency occur on takeoff from a ski-jump, there was valuable time to either jettison the stores or eject.
Testing further showed that the ski-jump reduced required wind-over-deck speed. As the upcoming Invincible class "Harrier carriers" were gas turbine powered, not needing higher speeds to achieve ideal wind-over-deck speeds meant a more inexpensive and less powerful powerplant would be needed for the ship, an added bonus in the atmosphere of financial austerity of the day.
It was also found that as the aircraft reached the ski-jump, there was a rapid increase in loading on the undercarriage and as a result, the design of the Sea Harrier was modified to incorporate structural reinforcement around the aft main undercarriage just below the blast deflectors of the aft nozzles.
The trials at RAE Bedford were tremendously successful and a 7 degree ski-jump was added to the already-completed HMS Invincible and to the HMS Illustrious. The lower-than-ideal angle was due to the presence of the forward Sea Dart SAM launcher on the bow. The last ship of the class, HMS Ark Royal, wasn't finished until 1985 an as such, it got a 40-foot deck extension and a 12 degree ski-jump, allowing it to launch a fully-loaded Sea Harrier. In 1986 the Invincible and Illustrious had their ski-jumps refitted to the same standard as the Ark Royal. In addition, when the HMS Hermes underwent its refit in 1979 from an assault carrier to one compatible with the Sea Harrier, it got a 12 degree ski-jump as well. The ski-jumps were crucial to Harrier GR.3 and Sea Harrier FRS.1 operations in the Falklands campaign in 1982.
The sea trials for the Sea Harrier FRS.1 began in October 1979 aboard the HMS Hermes and the first operational sea deployment took place in May 1980 aboard the HMS Invincible.
Source: BAe Sea Harrier (Warpaint Series No. 75) by Kev Darling. Warpaint Books Ltd, 2010, p1-8.
Thursday, April 15, 2010
In the run up to the 1967 Six-Day War in the Middle East, the Israeli Air Force was significantly outnumbered by the Arab air forces of Egypt, Syria, and Jordan and Iraq as well. Egypt's air force alone had 50 percent more comparable combat aircraft than the Israelis. As early as 1953 it was clear that neutralization of the Arab air bases would be vital in any future conflict. By 1960 operational planning centered around executing a simultaneous strike on all the Arab bases in range of Israel. The operations branch commander of the IAF, Rafi Har-Lev, and the top navigator in the air force, Rafi Sivron, began work on Operation Moked- the simultaneous neutralization of the Arab air bases.
The basis of the planning was intelligence- not only were the dispositions and activity cycles of the Arab squadrons determined, but they also were able to secure information on the runway thickness and design of the bases. Planning began in earnest in 1963 and was continually updated by the flow on intelligence from reconnaissance and human sources.
Since trapping the Arab combat aircraft on the ground was key, the Israelis and the French (before their abrupt change in foreign policy under Charles De Gaulle shifted away from Israel in 1967 after the Six-Day War) co-developed a new type of bomb specifically designed for destroying runways. Unlike conventional bombs, the new runway bomb was dropped from an altitude of approximately 100 meters and slowed by a parachute after release. A rocket then fired that drove the bomb through the runway and within six seconds the explosives detonated, creating a larger crater than would have been possible with a conventional bomb.
Aircraft carrying the new bombs would target eighteen air bases in Egypt, six bases in Syria, and two bases in Jordan. Once the runways were knocked out, the rest of the strike force could pick off the grounded Arab aircraft with guns and rockets. On 5 June 1967 at 0700 hours, the command went out from the IDF headquarters in Tel Aviv "Execute Moked". One-hundred sixty aircraft took off in the first wave. Jordanian radar detected the strike force but assumed that they were US Navy aircraft of the Sixth Fleet which were known to be in the region. At 0745 hours, Egyptian fighter aircraft were finishing up landing after their dawn patrols of the airspace adjoining Israel. Maintenance crews and pilots were in the process of heading to breakfast before the next patrol cycle began and that was when the Israelis struck. As each aircraft delivered the new runway bombs, they swung around and commenced strafing runs against the flight lines of trapped aircraft. While ten percent of the strike force was lost, within six hours the air forces of Egypt, Syria, and Jordan were neutralized. As Mordechai Hod, the commander of the Israeli Air Force said before the attacks "A jet aircraft is the deadliest weapon in existence- in the sky. On the ground, it is useless."
Operation Moked was a hugely successful gamble. The Israelis committed nearly all of its aircraft to the strikes, leaving only 12 fighters to protect Tel Aviv, something that the IDF commanders didn't fully reveal to the Israeli government.
The runway cratering bomb was further developed by the French weapons firm MATRA as the Durandal, named for a mythical French sword. The Durandal was put into production for the French in 1977 and in 1982, it was evaluated by the United States Air Force for use by the General Dynamics F-111. It would subsequently be cleared as well for the McDonnell Douglas F-15E Strike Eagle and received the designation BLU-107 and was used to great effect during Operation Desert Storm. The Durandal was designed for a shelf life of 11 years and if was carried on three sorties and not used, it was withdrawn from use. As such, the BLU-107 Durandal is no longer in use by the USAF.
Source: Air Combat Reader: Historic Feats and Aviation Legends, edited by Walter Boyne and Philip Handleman. Brassey's, 1999, p235-245.
Wednesday, April 14, 2010
Prior to the Second World War, international airline services from the United States were dominated by Pan American World Airways and its politically influential chairman, Juan Trippe. With implicit backing from the US State Department, Trippe forged Pan American into a "Chosen Instrument" of overseas American commerce with his extensive air network of services covering the Pacific, Latin America, and across the Atlantic. However, the demands of the Second World War resulted in most of the US airlines expanding their operations into overseas flying for the military to support the war effort. As a result, many airlines that had traditionally not flown outside US borders gained valuable experience in overseas operations.
As a result, many of those airlines began to look at what the postwar commercial aviation market might look like and airlines like American (via its subsidiary American Overseas Airlines), Trans World Airlines, and even smaller airlines like Northeast began to prepare applications to the Civil Aeronautics Board for international route authorities.
In March 1944, Senator Patrick McCarran of Nevada proposed a bill in Congress that would create what he called the "All-American Flag Line", a single international airline that would be jointly-0wned and operated by existing US airlines with an operating certificate dating prior to the 1938 passage of the Civil Aeronautics Act. McCarran's airline would be prohibited from domestic services and US airlines would be prohibited from international services outside of their participation in the "All-American Flag Line". Senator McCarran wanted to a single prestigious American international airline that all the other US airlines funneled traffic into from domestic gateways.
The "All-American Flag Line" would be a federally-chartered private airline starting with $200 million of federal capital and each participating US airline could purchase up to $50 million in stock of the airline. As Pan American had developed most of the international routes before the Second World War, Juan Trippe would hold ownership of 25% of the proposed airline.
This arrangement, of course, did not sit well with the smaller US airlines. While the US majors like TWA, United, American, and Eastern saw the McCarran bill as a way to gain entry into the international arena without the capital expenditure of expanding overseas on their own (since this seed money would be provided by the federal government), smaller airlines balked at the price of investment and being consigned to having a small voice compared to that of Juan Trippe, much less that of the larger airlines as well.
One of the most eloquent and vocal critics of the McCarran bill was Carleton Putnam of Chicago & Southern Airlines. In June 1933 as a young law student, Carleton Putnam started Pacific Seaboard Airlines operating Bellanca Pacemakers between San Francisco and Los Angeles. When President Roosevelt canceled the air mail contracts in 1934 during the infamous Air Mail Scandal, Pacific Seaboard Airlines lost its primary revenue stream. After the US Army Air Corps tried in vain to carry air mail, the contracts were once again put up for bid and Putnam in desperation to save his small airline bid on an air mail route in the Mississippi Valley that connected Chicago to New Orleans. To the surprise of many, Putnam won the contract and in 1934 he moved his entire operation to Memphis, Tennessee and on 17 July 1935 he launched passenger services as Chicago & Southern Airlines.
During the Second World War, Chicago & Southern operated a vital contract flying troops and cargo throughout Alaska during the Aleutian campaign to oust the Japanese from the area. Putnam even applied for postwar international route authorities to fly to Singapore and Batavia (modern day Jakarta) from Chicago via Alaska in what may very well be the first proposal to use a Great Circle Route that is now a primary routing for air traffic between North America and Asia.
Trippe of course was supportive of the McCarran bill and he certainly didn't expect such tenacious opposition from someone like Chicago & Southern and Carleton Putnam. Putnam rallied the other smaller airlines, pointing out that it should be the free market and competition that should determine who was most suitable for international services rather than have the government virtually enshrine Pan American as the default international airline.
To go against someone as powerful in Congress as Senator McCarran who was highly influential in aviation affairs and to simultaneously take on Juan Trippe of Pan American, probably the most influential airline head of the day? That's quite a set of brass ones and Putnam managed to pull it off and have the McCarran bill killed off. While Chicago & Southern Airlines didn't get its Great Circle route to Asia, it was handsomely rewarded by the CAB with route authorities into Pan Am's traditional Caribbean stronghold with services to Cuba, Jamaica, Haiti and the Dominican Republic, Puerto Rico and all the way to Caracas, Venezuela from New Orleans.
Carleton Putnam won the admiration of many in the industry for his stand against McCarran and Trippe, most importantly with C.E. Woolman, founder and head of Delta Air Lines. Woolman saw in Putnam and Chicago & Southern a kindred spirit that shared his own business ethics and ideals. Having grown weary of trying to expand services to New York but failing thanks to the maneuverings of Eastern Air Lines and its acerbic president, Eddie Rickenbacker, Woolman embarked on expanding Delta westward through a merger with Chicago & Southern that was finalized in 1953.
And perhaps more importantly, the stage was set for overseas services by any US airline that could show to the CAB that it had the wherewithal to operate internationally, cracking Pan Am's long dominance of international services.
Source: Delta: The History of the Airline by W. David Lewis and Wesley Phillips Newton. University of Georgia Press, 1979, p200-201.
Monday, April 12, 2010
I've always had a soft spot for the Boeing 727. Maybe it was all those flights as kid growing up in the Midwest where we'd board a Braniff Flying Colors 727 out of Wichita and head off to different parts of the country back in the day when you flew Braniff north or south out of Kansas to interline with different airlines to head to the East Coast or West Coast. Flights to the south usually interlined with Continental or American and flights to the north interlined with United, sometimes TWA if I remember right from my youth. But even those flights were 727s, too, and then one day all of a sudden it seems, sometime after September 11, the 727s were all put out to pasture by most of the US majors. I could go on and on (but thankfully won't) on why I think the 727 is the Chuck Norris of jetliners, but suffice to say for today's aviation trivia there's just one feature, though not unique to the 727, adds to that coolness for "Trisaurus Rex".
There was a JATO option. That's right. Rocket assisted takeoff. What a shame it wasn't picked up by everyone else, but it was an option on the 727-200 which of course was a lot heavier than the shorter 727-100. Until the 727-200 Advanced came along and included JT8D engines if increased power, the early 727-200s were a bit short on the power stick due to the heavier weight but essentially the same engines as the -100s.
Now don't everyone write me, I know the reasons why the JATO option didn't roll out across the board for most production 727-200s. There were only 12 727-200s that were built with the JATO provision and they were actually the more powerful 727-200 Advanced versions. Mexicana was in a unique position of serving several high-altitude airports in its network where the 727-200 as built would have been payload restricted to account for the possibility of the loss of one of the three engines at takeoff.
As a side track to illustrate that point, at airports at higher elevations, particularly on hot days, wings will generate less lift and jet engines will develop less power than at a lower elevation airport. That's why the runways at airports like Denver or La Paz, Bolivia, are so long. In fact, back in the 1970s many US airlines didn't sent the 727-100QC variants to Denver Stapleton Airport as the heavier structural reinforcing of the main deck to handle cargo loads cut into the passenger payload during the summer months.
Mexicana took delivery of twelve 727-200s that got around this limitation by having a JATO installation in the lower aft fuselage just behind the wings. These aircraft could be identified by having a shallow dorsal fairing ahead of the #2 intake that accommodated some of the rerouted avionics and air conditioning ducting that was displaced by the JATO provision. There's a misconception that this fairing is a reinforcement brace, though.
The aircraft were unofficially designated 727-200/JATO by Boeing and the rocket installation was intended for emergency use only when flying out of a hot and high airport at maximum gross weight. Without the JATO, the aircraft would have to be payload restricted to account for the need to reach a safe altitude in the event of an engine loss after committing to takeoff. By having the JATO provision, Mexicana could operate its 727-200s at full payload. In the event of a loss of engine at past V1, the JATO unit would fire and allow the heavily-laden jet to reach a safe altitude and get aerodynamically cleaned up.
The JATO provision was eventually made obsolete by later developments in the JT8D engine that featured APR- automatic power reserve. It sensed a power decrease from one of the engines failing on takeoff and automatically boosted the power to the remaining two engines by a significant margin.
Source: Boeing 727 (Modern Civil Aircraft:13) by Peter Gilchrist. Ian Allan Press, 1996, p62.
Sunday, April 11, 2010
If there was any one factor during the Cuban Missile Crisis of 1962 that could have escalated the situation out of the control of President Kennedy and Premier Khrushchev, it wasn't the threat of an American invasion of Cuba and believe it or not it wasn't the presence of the SS-4 and SS-4 medium-range ballistic missiles that targeted most of the Continental United States. It was the presence of tactical nuclear weapons not just on Cuba itself (2 kiloton warheads on the battlefield FROG rockets) but the tactical nuclear weapons on the periphery of the crisis that had release authority vested in lower-ranking officers.
Case in point, each of the five diesel-electric submarines the Soviet Navy deployed to Cuba to monitor the merchant fleet that was bringing war materiel and personnel the island each had single nuclear-tipped torpedo amongst the conventionally-armed torpedoes normally carried. There were tense moments and the quarantine line Kennedy ordered ships carrying military cargoes bound for Cuba had to turn around or stop and be inspected by US Navy warships and in some cases, US ASW forces were tracking and hounding these very submarines, tempting their captains to fire their single nuclear torpedo. But it didn't happen there, thankfully, but there was a routinely scheduled U-2 flight from Alaska half a world away that nearly triggered an escalation of the Cuban Missile Crisis.
On the same day on 27 October 1962 Major Rudolf Anderson, Jr's U-2 flight was shot down over Cuba by an SA-2 SAM missile, a world away at Eielson AFB in Fairbanks Major Chuck Maultsby took off in a U-2 headed to the North Pole on a high-altitude sampling flight to try and collect particle debris from Soviet nuclear tests on the Arctic island of Novaya Zemlya. Upon collecting the required samples, Maultsby set course for Alaska but erred in his navigation and instead started heading towards the eastern peninsulas of Siberia. A rescue Douglas C-54 Skymaster airborne to support his flight noted the start of sunrise and Maultsby reported he didn't see a sunrise indicating he was far to the west of the return path and entering Soviet air space.
US radar sites in Western Alaska detected the MiG-19 fighter scrambled to intecept the lost U-2 who made an immediate turn to the east post-haste! At the same time, two USAF Air Defense Command Convair F-102 Delta Dagger interceptors were scrambled to counter the MiGs and guild the U-2 home. On each Delta Dagger were nuclear-tipped GAR-11 Nuclear Falcon missiles.
Five days earlier when the Strategic Air Command and the US armed forced worldwide went to DEFCON-2 (one stage of full war with the Soviet Union), tactical nuclear weapons like the GAR-11 Nuclear Falcon were loaded on ADC interceptors and entrusted to lower-ranking officers. The GAR-11's warhead was only 0.25 kiloton, but there were larger warheads equally entrusted like the 40-kiloton warhead used on the Nike-Hercules SAM sites that protected the US industrial centers.
So now over the Bering Sea, nuclear armed F-102 Delta Daggers have scrambled under DEFCON-2 preparations to rescue an errant U-2 under pursuit by two Soviet MiG-19s. Maultsby didn't have enough fuel to land back at Eielson AFB but made a deadstick landing at a small Alaskan airfield and the MiGs broke off pursuit and returned to the bases. The Air Defense Command F-102s never got into missile engagement range of the MiG-19s, but the event sent reverberations through Washington and Moscow. Moscow saw the U-2 flight as a prelude to a nuclear bomber strike over the North Pole and Khrushchev protests vigoruously on the 28th to Kennedy, berating him for this "provocation". Kennedy, in a rare moment during the Cuban Missile Crisis, was forced to apologize to his protagonist and to seek every measure to make sure it doesn't happen again.
Kennedy was pissed, to say the least, berating his special Executive Committee of close advisors (ExComm) expasperated "There's always some sonofabitch that doesn't get the message!" Privately Khrushchev consigned the U-2 flight as a navigational error and not a true prelude to an attack- quite possibly the smartest decision he made during the crisis!
Source: DEFCON-2: Standing on the Brink of Nuclear War During the Cuban Missile Crisis by Norman Palomar and John D. Gresham. John Wiley and Sons, Ltd, 2006, p-120-153.
Saturday, April 10, 2010
As the pace of technological improvements in aviation march forward, sometimes promising aircraft designs get shafted by rival designs that offer more of something- more speed, more payload, more range or just plain more of everything. The lucky ones amongst the short-shrifted go into limited production like the Bristol Britannia or the Convair 990. Some only fly as prototypes like the Avro Canada C102 Jetliner. And most never make it off the drawing boards like the Douglas C-132. Most of the ones that go into even limited production are noted by history- but there are some aircraft designs that despite that, are nearly forgotten to aviation history.
One of those aircraft was the ANT-35 from Andrei Tupolev's design bureau in the interwar period of the 1930s. The beginnings of the ANT-35 started out rather unusually in a contest held in May 1934 in the magazine "Za Roolyom" (At The Wheel) and chaired by the Aviation Research Technical Society (Avia-NITO). The contest called for a high-speed airliner in both single- and twin-engine categories that were to have a speed of 400-450 kilometers per hour, a range of 1,250-1,500 kilometers, a cruising altitude of 7,500 meters and able to carry five to twelve passengers with their baggage. Several dozen designs were submitted to the magazine and while none were actually built, the contest influenced the design of future Soviet airliners.
Andrei Tupolev didn't participate in the contest but he had been watching it from the sidelines and decided to go ahead in August 1935 and build an aircraft to the outlined specifications. To save time and get his design into production as soon as possible, a new passenger-carrying fuselage was mated with the wings, tail, and undercarriage of the Tupolev SB (ANT-40) light bomber. To insure a high speed, special attention was paid to the fit and finish of the components to insure a smooth external line (in contrast to most Soviet designs of the day which were decidedly "rougher") for drag reduction. Two license-built French Gnome-Rhone 860-horsepower Mistral radials were used for the engines. The cabin was heated and fully-soundproofed with ten reclining passenger seats as well as individual ventilation and lighting for each seat- keep in mind that was something that wasn't standard in airliners until the start of the jet age in the 1950s- and this is 1935- in the Soviet Union, no less! Compared to other contemporary Soviet aircraft, the ANT-35 was also lavishly-equipped with a full avionics fit including autopilot, radio equipment and navigation gear.
Tupolev made sure all of the latest in aviation technology was included in the ANT-35- from close-fitting NACA cowlings on engines, oil coolers submerged in the wing roots, hydraulically-operated flaps, even rubber shock-absorbers on the engine mounts. He had every intent on making the ANT-35 not just the fastest airliner, but also the most comfortable and advanced airliner flying.
The first flight of the prototype ANT-35 was made on 20 August 1936 and at normal gross weight it easily cruised at 390 kilometers per hour, making it one of the fastest airliners of the day. The main deficiency noted on the prototype was the lack of headroom in the cabin but it was otherwise an extremely satisfactory design in the opinion of the test crews. The second prototyp,e designated the ANT-35bis, incorporated a cabin with 15 centimeters of more headroom and more powerful license-built American 1,000-horsepower Wright Cyclone radial engines. The improved version flew in late 1937 and served also as a pattern for production of what was to be designated the PS-35 airliner.
Large scale production eluded the ANT-35/PS-35, though. At the same time, the Soviet Union obtained a license to produce the Douglas DC-3 as the Lisunov Li-2 (also designated PS-84) with the same engines as the ANT-35. Although Tupolev's design was much faster, the DC-3/Li-2 could carry more passengers and cargo over a longer range and as a result, Aeroflot and the Soviet Air Force only took delivery of 9 ANT-35 airliners total. Before the outbreak of the Second World War, the ANT-35 was used on the Moscow-Prague and Moscow-Stockholm routes but in 1941 were shifted to high-priority express flights between Moscow and the cities of Lvov and Odessa. During the war the dwindling number of ANT-35s capitalized on their high speed to deliver supplies to partisans in the German rear flanks as well as medical and food supplies to encircled Red Army units. The last aircraft was retired from service in 1944 to fade into obscurity, eclipsed by the Douglas DC-3 and the many variants Lisunov built that were unique to Soviet service.
Source: OKB Tupolev: A History of the Design Bureau and its Aircraft by Yefim Gordon and Vladimir Rigmant. Midland Publishing, 2005, p64-66.
Thursday, April 8, 2010
One of the toughest targets in North Vietnam during the long war there was the Thanh Hoa Bridge over the Song Ma River. The bridge was a massive steel truss and concrete structure that carried a railroad down the center and a two lane road way on each side and was a major supply choke point from Hanoi and the harbor of Haiphong. Crossing the river at its narrowest point, sharp limestone ridges on each side gave it the nickname Ham Rong, or "Dragon's Jaw" as the American pilots referred to it. Because of its strategic nature on the supply route to the battlefields along the DMZ and to the Viet Cong in South Vietnam, the Thanh Hoa Bridge was a significant target and was recognized as such by the North Vietnamese who protected the area with some of the densest antiaircraft defenses outside of Hanoi and Haiphong.
Despite the initial attacks by F-105s from bases in Thailand, the bridge which was over-engineered, refused to drop. One USAF attack had 79 aircraft of varying times involved at the same time and yet the bridge still stood. Late that year the Armaments Development Laboratory at Eglin AFB in Florida had been doing research on using high-explosive weapons that focused their energy- similar to a scaled up version of a shaped charge used in anti-tank warfare. The command staff of the Pacific Air Forces running the USAF air campaign in Vietnam was notified of the possible destructive power of these new weapons, but they could only be carried by cargo aircraft and the only suitable would be the Lockheed C-130 Hercules. Since the AA defenses of the Thanh Hoa Bridge were so intense, a plan was formulated to have C-130s drop the weapons up river and let them float down to the bridge and detonate. The opeation was given the code name Carolina Moon.
Two experienced crews were chosen from the 314th Troop Carrier Wing at Sewart AFB, Tennessee. One crew was led by Major Richard Remers and the other crew was led by Major Thomas Case, both crews from the 61st Troop Carrier Squadron.
On 30 May 1966, Remer's crew took off first in a C-130E from Da Nang AB just after midnight local time. With a crew of seven, they flow at 100 feet above the South China Sea and then turned in towards the target area, remaining at 100 feet. There were two navigators aboard Remer's Hercules and there were two drop zones upstream from the Thanh Hoa Bridge selected. The first one was 2 miles up river and the second one was just a mile up river. Upon reaching the first point and meeting no resistance, Remer pressed on the the next drop point. Soon anti-aircraft gunfire opened up across the river valley but the successfully dropped their five Carolina Moon weapons in the river and flew all the way back to Da Nang on the deck, rarely exceeding 100 feet.
The following day reconnaissance photos showed the bridge still standing so that night, the second mission led by Major Case took off just over a hour after midnight from Da Nang. As with the previous night's mission with Major Remer, USAF F-4s conducted diversion strikes in the area and one of the pilots reported heavy anti-aircraft fire and large ground flash about 2 minutes before the drop zone for the weapons. Major Case's crew was never heard from again and it wasn't until well after the war ended into the present day that the crash site for the Hercules was finally identified with excavations under way.
It was later found that the special bombs did in fact detonate under the bridge as designed, but they simply lacked enough force to bring down the spans of the Thanh Hoa Bridge. It wasn't until 1972 during the Linebacker missions that F-4 Phantoms dropping brand-new laser-guided bombs (LGBs) managed to finally put the Dragon's Jaw out of commission.
Source: C-130 Hercules: Tactical Airlift Missions, 1956-1975 by Sam McGowan. Aero Publishers, 1988, p122-124.
Wednesday, April 7, 2010
Noted aviation historian Walter Boyne described Operation Ranch Hand as "a heart-rending example of how good airmen can be forced to do unpleasant work when it is determined that the war effort demands it." There are few events in aviation history that evoke strong debates even to this day as those that surround the nine year use by the US military of the defoliant Agent Orange in Vietnam. The aerial spraying of herbicides was used initially in the United States for weed control but was on a strictly limited basis in the immediate post-war period. The first "military" use of aerial herbicide spraying came during the Communist insurgency in Malaysia during the 1950s when the British used it on a limited basis to keep communication lines through the jungle clear.
The British use of air-delivered defoliants was cited by by proponents in 1961 in the proposal presented for President Kennedy's consideration. Supported by the Secretary of Defense, Robert McNamara, the requisite approvals were also secured from not just the President but also President Ngo Dinh Diem and the government of South Vietnam. Some in the administration had raised the issue that use of the defoliants might be considered chemical warfare, but McNamara felt that operational necessity to reduce Viet Cong ambushes and hideouts in South Vietnam made the risk worthwhile. On 3 November 1961 McNamara authorized the use of defoliants in South Vietnam to combat the Viet Cong ambushes on US and ARVN units.
The USAF already had a limited ability already present for the aerial spraying of defoliants as part of its public service work on mosquito-control projects in the southeastern United States. At the end of World War II, a Special Aerial Spray Flight (SASF) was established at Langley AFB in Virginia to undertake mosquito-control spraying. Activated in 1961 for Operation Ranch Hand, the SASF received six Fairchild C-123 Providers for modification into aerial sprayers. Inside the cargo hold of the Provider would be a 1,000 gallon tank connected to spray equipment mounted on the wings that could deliver the herbicides. To the surprise of the commander of the SASF, he found no shortage of volunteer pilots to fly the first Ranch Hand missions despite the proviso that they would wear civilian clothes, fly unmarked aircraft, be on temporary duty to Vietnam for extended periods of time and if shot down and captured, would not be acknowledged as USAF personnel.
There were several different herbicide options, each differing in the proportions of different chemicals present in the mix. Each option was given a color code name. Some of the options available included Agent White, Agent Blue, Agent Purple, but the most widely used option would become infamous- Agent Orange.
Once the first six C-123 Providers were modified, they deployed to South Vietnam and arrived in-theater in January 1962. The aircraft fleet ebbed and flow with the war, peaking at 25 C-123s in 1969. Over 20 million gallons of Agent Orange would be sprayed over 6 million acres in South Vietnam. Unlike a lot of other military experiments in Vietnam that were failures, the use of Agent Orange did work in denying the Viet Cong jungle cover in strategic areas of the country. After a significant decrease in the number of ambushes on US Army/ARVN units in the first year of use, Defense Secretary McNamara authorized an expansion of Operation Ranch Hand to include areas of the Ho Chi Minh Trail used to infiltrate supplies and personnel into South Vietnam, and more significantly, to use Agent Orange for the destruction crops in Viet Cong strongholds to try and limit their food supplies.
The Ranch Hand effort expanded significantly in 1962 as a result as the C-123s wore South Vietnamese Air Force markings (and later in the war, full USAF markings). In fact, the first US aircraft shot down in Vietnam was a Ranch Hand C-123 on 2 February 1962, killing all three crew.
The first protests by North Vietnam were echoed by the Soviet Union and China in 1961 but met with a muted response by other nations. But criticism grew both in the United States and abroad as the program was expanded in 1962 to include crop destruction as the Viet Cong had successfully blended into the local population and as a result, the crops of many "friendly" South Vietnamese were also destroyed. By 1965 scientists in the United States were protesting the use of Agent Orange and the banner was subsequently picked up by the media and the anti-war movement of the day. Three years later, President Nguyen Van Thieu of South Vietnam felt that Operation Ranch Hand was counterproductive but his concerns were overridden by a 1969 report prepared by the American ambassador to South Vietnam with a committee he appointed that showed that the use of the three main herbicides, Agents Orange, Blue, and White, were not harmful. Ambassador Ellsworth Bunker's report quite obviously had the opposite effect and further inflamed the controversy further. Finally, on 22 December 1970 Secretary of Defense Melvin Laird advised President Richard Nixon that any herbicide use should conform to delivery and use standards in place in the United States which effectively ended the use of Agent Orange in South Vietnam. The last Ranch Hand flight flew on 7 January 1971.
Since the end of Operation Ranch Hand, millions of dollars in claims have been paid out by the manufacturer of Agent Orange and the Veterans Administration for the deleterious health consequences of the widespread spraying of the herbicide for nine years. To this day health effects are still being seen in even in individuals a generation removed from those originally exposed to Agent Orange. In fact, when the National Museum of the United States Air Force in Dayton, Ohio, was to put on display a C-123 Provider that had taken more battle damage than any other of its type, it was subject to a political and legal controversy by local environmentalists that resulted in the aircraft being sealed up for display despite the fact no traces of Agent Orange could be found in the airframe.
Source: Beyond the Wild Blue- A History of the United States Air Force, 1947-2007, Second Edition by Walter J. Boyne. Thomas Dunne Books/St. Martin's Press, 2007, p157-159.
Tuesday, April 6, 2010
Navy Weather Reconnaissance Squadron FOUR (VW-4), based out of NAS Jacksonville, Florida, for many years was responsible for the Navy's contribution to the hurricane hunting effort shared with the US Air Force and the Department of Commerce. For most of VW-4 history it flew the Lockheed WC-121N Warning Star, a veersion of the EC-121 airborne early warning version of the Lockheed Super Constellation. While not one WC-121N was ever lost on a hurricane hunter mission, by 1969 the Navy was looking at replacing the venerable old bird with a more advanced weather reconnaissance aircraft.
During the 1969 Atlantic hurricane season, Hurricane Inga formed near the Lesser Antilles and an unusual combination of weather factors had the hurricane wandering in two loops south of Bermuda (Inga would last 25 days, becoming the 4th longest lasting Atlantic hurricane in history). The Navy took the opportunity to perform a unique fly off of two candidate replacement aircraft along with the existing WC-121N Warning Star. They flew a Lockheed C-130 Hercules, a Lockheed P-3 Orion, and a Lockheed WC-121N Warning Star (Huh! All Lockheed products, too. Go figure.) in trail formation on repeated penetrations of the eyewall of Hurricane Inga. Fifteen miles separated each aircraft from the next aircraft in the formation as over twenty low-altitude penetrations were made into the eye. A multitude of factors were evaluated from propulsion systems, flying qualities and general handling in the severe turbulence of the eyewall as well as the structural integrity and payload capacity. The working environment was also taken into consideration considering the long flights that were a routine part of hurricane hunting.
Although both the C-130 and P-3 did well in the evaluation flights into Hurricane Inga, the Navy selected the P-3 Orion as the next Hurricane Hunter. Interestingly the USAF has been using the C-130 since 1960 for the hurricane hunting mission.
Existing P-3As were taken from the Navy maritime patrol fleet and stripped and reworked at Lockheed's Ontario, California, facility. All the ASW and sensor systems were removed and a weapons-bay mounted APS-20 radar was installed with a large M&M-shaped radome (and thus called the "M&M radome"), structural strengthening of the wings and a whole host of meteorological data-gathering sensors. The new WP-3As also had dual INS, Doppler and Omega navigation systems, one of the most extensive and advanced systems to be installed in an aircraft at the time. The interior layout remained essentially the same as that of the fleet P-3 Orions with the operator consoles reconfigured for weather research and data gathering.
The new WP-3A's first taskings with VW-4 were with Project Stormfury, a long running joint Department of Defense/Department of Commerce research project into cloud seeding of hurricane storm bands in an effort to attenuate the storm's intensity. Though the results were inconclusive, the idea of the military being involved with weather modification became a political hot potato with accusations by uninformed quarters of the "weaponization of weather". The WP-3As also participated in polar ice reconnaissance and winter storm studies on the US East Coast. In addition, the WP-3As were also deployed overseas to provide weather support and research for fleet operations.
In late 1974 as the result of post-Vietnam budget cuts, the Navy announced the closing down of VW-4 and its hurricane hunting mission which became official on 30 April 1975 and the WP-3As were pulled out of service and demodified for other roles. The military's contribution to hurricane hunting would be handled entirely by the USAF in cooperation with the National Oceanic and Atmospheric Administration (NOAA). Ironically, NOAA took delivery in 1976 of two even more highly-modified Lockheed P-3 Orions designated WP-3D which were even more advanced the Navy's WP-3As and still serve to this day.
Source: The Age of Orion: The Lockheed P-3 Story by David Reade. Schiffer Publishing, 1998, p119-122.
Monday, April 5, 2010
Some planes are like the Rodney Dangerfields of aviation- they just don't get any respect. If there's one plane that I think of in that regard, it has to be the Grumman E-2 Hawkeye. Development began on the Hawkeye in 1956 as a replacement of the Grumman WF/E-1 Tracer as the "eyes" of the carrier battle group. The first E-2A Hawkeyes entered fleet service in 1964 and were a quantum leap over the early E-1 Tracer. Since then, Grumman (and now Northrop Grumman) have made continual refinements to the E-2 Hawkeye's systems that while the external appearance of the aircraft hasn't changed significantly, the radar systems are far more advanced than what went to sea in 1964.
The latest version of the E-2 is the E-2D Advanced Hawkeye. While the distinctive eight bladed propellers on each engine are new, they're not unique to the E-2D Advanced Hawkeye as they have been retrofitted to current E-2Cs in the fleet. The heart of the changes to the E-2D are all internal, as have most of the significant changes to the Hawkeye over the years.
The needs for both overland/littoral as well as oceanic surveillance have resulted in the AN/APY-9 radar being a unique hybrid of an electronically-scanned unit inside the rotodome that also was mechanically scanned by rotating the entire unit as well. The radar couldn't be a true AESA (active electronically scanned array) due to weight and space limitations for a carrier-borne aircraft. The transmit and receive equipment for the new radar are located in the fuselage and connect to the antenna in the rotodome via a high power RF coupler. As a result, the rotodome can rotate and be locked down to focus on a specific threat sector as the Navy's primary requirement for the new system was for theater ballistic/cruise missile defense. The new radar compared to the AN/APS-145 of the E-2C has a staggering 300% increase in the volume of sky it can search.
Interestingly the data systems on the new version of the Hawkeye are based on commercial off-the shelf (COTS) technology with a fiber optic local area network (LAN) using commercial Ethernet standards and a mission computer running Linux. This was done to facilitate future upgrades which, in essence, could be done with the ease of computer infrastructure upgrades in the consumer world.
The external appearance of the E-2D Advanced Hawkeye is essentially unchanged from the current E-2C, but the aircraft is 1,500 lbs heavier and as a result, a white triangle is painted on the nose ("delta" for the E-2D) as a recognition for the carrier LSOs that the arresting gear has to be set for a higher weight than other E-2 versions.
When the last E-2D Advanced Hawkeye is delivered to the fleet in 2021, it will have been an astounding fifty-seven years since the Hawkeye first went to sea in 1964! Maybe it doesn't get a lot of the attention and glory that the fast jets of the carrier air wing gets, but what might end up being 70+ years of service sure as hell gets my respect!
Source: Air International, March 2010, Vol. 78, No. 3. "Twenty-First Century Hawkeye" by Dave Majumadar, p38-47.
Saturday, April 3, 2010
Early on in the postwar period both the United States and the Soviet Union realized the potential deterrent value of basing nuclear missiles on submarines. Both nations looked at derivatives of the German V-2 missile but in the United States development first focused on the use of cruise missiles on submarines but as a deterrent, the system was slow. Cruise missiles of the day flew no faster than the jet bombers and were thus prone to interception and the need to launch from the surface made the sub platform vulnerable to detection and attack.
In the Soviet Union, however, the nuclear-tipped missile in its various forms was seen by Premier Nikita Khrushchev as a way of leveling the playing field against the US military without the great expenditure of cost needed by large fleets of ships, aircraft and tanks. While sub-launched cruise missiles were developed, they came afterwards and as an insurance on the missile development. Several days ago I talked about a secret precision-guided version of the Russian Scud missile. What's little known about the Scud is that it was also the Russian's first sub-launched ballistic missile (SLBM). In fact, the operational deployment of the SLBM version of the Scud, designated the R-11FM, was the first operational deployment in the world of an SLBM when it went to sea in 1956, five years before the American Polaris A-1 SLBM went to sea aboard the USS George Washington.
As the Russians were quite aware of the start of the development of the Polaris in the mid-1950s, time was of the essence in fielding an operational SLBM and the Scud was selected for adaptation rather than use an all-new design. As the American George Washington-class ballistic missile submarine was based on a stretching of the Skipjack attack submarine, the Russians similarly stretched the Project 611 attack submarine (NATO code name Zulu) into the 611AV. As the missile was too long to enclose in the hull, the sail of the submarine was stretched to hold two launch tubes that held the missiles which extended from the hull and into the sail.
Word began in 1954 and the first technical hurdle was how to launch the missile from underwater. As the R-11FM system was intended to be an interim option, this hurdle was deferred to the next series of missiles under development. So for the time being, the R-11FM would be launched from a surfaced submarine. The missile would be elevated out of its launch tube and then fired.
The second hurdle was how to launch the missile when the submarine was moving due to sea motion. As the land-based Scud had to be aligned a certain direction for launch, the sub-based version was mounted on a launch table that was gyroscopically stabilized in three axes similar to what was done for battleship turrets (in fact, the stabilization system was designed by a naval artillery design bureau in Leningrad). Once launch was commanded, the system would only fire the missile if the stabilized table was in the proper position.
In the fall of 1954 a series of test launches were made from ground-based test platforms and on 16 September 1955 the world's first submarine-launched ballistic missile launch took place in the White Sea. After further testing, the R-11FM and the Project 611AV submarines became operational with the Northern Fleet in 1956 and the Pacific Fleet in 1959.
The system was abysmal, to say the least. Poor quality control and the need to carry the hypergolic fuels for the R-11FM led to numerous accidents and launch failures. The CEP of the missile was an atrocious 7 kilometers (meaning that 50% of the time the missile would hit inside a 7km circle) compared to 1-2 kilometers for the land-based version. The 611AV submarine had to maintain a steady course, depth and speed for 2-4 hours before launch for the launch system to properly align and once surfaced, it took five minutes to launch the first missile and another five minutes for the second missile to be fired.
The Soviet Navy was very reluctant to take the missile into service, but pressure from Premier Khrushchev and the defense minister, Dmitri Ustinov, resulted in six 611AV submarines going into service with the R-11FM. The rationale was that while impractical and cumbersome, it was the first step in getting practical experience of launching missiles at sea.
Source: Scud Ballistic Missile and Launch Systems 1955-2005, New Vanguard #120 by Steven J. Zaloga. Osprey Publishing, 2006, p8-11.
Friday, April 2, 2010
It was tough going if you were assigned to one of the USAF Tactical Air Command's Troop Carrier Squadrons (TCS) in the 1950s. In the hierarchy of the day, the pilots and crews of the airlift squadrons picked up the still-used sobriquet of "trash-haulers" and while the airmen in the bomber and fighter squadrons flew advanced aircraft that were often the cutting edge of technology and performance. The bomber crews of the Strategic Air Command won the lion's share of the USAF budget in the name of nuclear deterrence and the fighters of the Tactical Air Command were setting world records for speed and altitude and carrying the latest in missile and radar equipment.
But the troop carrier squadrons by and large were still flying piston radials in aircraft with technology not far removed from the aircraft of World War 2. Even the long-haul transport crews of MATS, the Military Air Transport Service, had it better than the guys who slogged around on intratheater missions in Douglas C-47 Dakotas and Fairchild C-119 Flying Boxcars. The C-119 was so underpowered that its single engine performance was near-abysmal. Back then, the graduates of USAF flight training with the lowest scores went to the troop carrier squadrons.
That all changed when the Lockheed C-130 Hercules made its first flight in Burbank, California in 1954. The Hercules didn't have the sleekness and speed that its fellow Lockheed stablemates had, but it was tough, practical, and most importantly, powerful. The early model C-130s were hot ships. On the first flight of the Hercules prototype in August 1954, an aircraft with its weight would have usually needed at least 5,000 of runway to take off. The Herk prototype? It leapt off the ground in only 855 feet with the power of four Allison T56 turboprops. Spectators and invited guests were astounded that this portly aircraft had such performance. Lockheed chairman Robert Gross even exclaimed "Look at her climb!"
The first operational C-130As went to the 463rd Troop Carrier Wing at Ardmore AFB, Oklahoma. Pilot were ecstatic about flying a tough transport that handled like a fighter jet. There were even TAC fighter pilots who were transferring to the Hercules. Suddenly Herk pilots could walk into any officers' club with pride knowing that they had a "trash-hauler" that even the fighter jocks wanted to fly. It's pretty safe to say that the arrival of the C-130 Hercules was a massive morale boost for the troop carrier squadrons of the Tactical Air Command.
While the first operational C-130 units were with the 463rd TCW in Oklahoma, the Hercules training unit would be the 314th Troop Carrier Wing at Sewart AFB in Tennessee. There at Sewart would pilots, loadmasters and mechanics be trained on the Herk. While the 314th was still getting operational, flight crews from the 463rd TCW took their new mounts to bases all over the United States and participated in airborne exercises with the Army who were also excited about the arrival of the Hercules.
One of the units, the 774th Troop Carrier Squadron "Green Weasels" that was part of the 463rd TCW at Ardmore AFB happened to be at Fort Campbell, Kentucky for a week-long exercise with the 101st Airborne Division. One day the winds canceled a scheduled airborne drop, but four of the 774th TCS's C-130s were ready to go. So the flight crews took off anyway to make use of the time to get some formation flying practice in and spent several hours flying low over Kentucky and Tennessee honing their skills. On their return to the airfield at Fort Campbell, they made several low passes at high speed and in tight diamond formation. It donned on them- hey, why not form a demonstration team like the Thunderbirds to demonstrate the new Hercules everywhere?
Back at Ardmore AFB, they worked on their demonstration routine and suggested that they fly the routine for the personnel of the 314th TCW at Sewart AFB to show off the new planes that they'd be getting. TAC Headquarters approved the plan and the demonstration was a success. At first they called themselves the Thunderweasels, a combination of the Thunderbirds and the Green Weasels nickname of the squadron, but they settled on becoming "The Four Horsemen" after Knute Rockne's famous football offensive team at Notre Dame in 1924.
The Four Horsemen won official recognition from the USAF as an aerial demonstration team and from 1956 to 1960 they performed their routine of tight formation flying and sharp turns throughout the United States and even went overseas to Europe and the Far East. During one performance, the number three Hercules lost one of the outboard engines which had to be shut down. The crew feathered the prop and continued with the air show routine without a hitch!
HistoryNet has a good article that was published in Aviation History on the Four Horsemen I suggest for further reading.
Source: C-130 Hercules: Tactical Airlift Missions, 1956-1975 by Sam McGowan. Aero Publishers, 1988, p7-11.