Genesis of the Predator UAV

Leading Systems' Amber UAV, grandfather of the Predator

In the mid-1970s, Abraham Karem, a designer of high-tech weaponry for the Israeli Defense Forces, emigrated to the United States but despite his credentials working with the Israeli military, found himself unable to get employment with any of the major American defense contractors. Karem had some innovative ideas for unmanned aerial vehicles (UAVs), so ended up starting his own company, Leading Systems, in the garage of his home in Irvine, California, to pursue his UAV concepts. In 1982, the Defense Advanced Research Projects Agency, DARPA, was providing seed money to small companies that offered innovative solutions to problems outlined by the US military. One such problem was a need for an advanced UAV that could provide reconnaissance imagery while having a long endurance but be both inexpensive and reliable. The classified DARPA program TEAL RAIN was established to study the technology for long-endurance UAVs. The problem at the time was that previous long endurance UAVs exemplified by the Boeing Condor as well as the Compass Cope program were large and prohibitively expensive. Two years after he founded Leading Systems, Abraham Karem secured seed money from DARPA to develop his concepts and in 1984, he received a contract to develop a classified reconnaissance UAV code-named Amber. While most competing companies adapted existing piston engines from snowmobiles and motorcycles for their designs, Karem used the DARPA seed money to hire engineers willing to design and build engines custom tailored for the Amber program. 

The first Amber UAV flew in 1986 (just two years after Karem got the DARPA contract!). Karem designed Amber to fold up and be fired from a standard torpedo tube- the US Navy was one of the backers of the Amber project- as a result, it had a slender fuselage with a parasol wing and an inverted-V tail with a pusher prop. Two types of Amber UAVs were planned- the "A" version had a pointed nose section carrying a warhead and was to be a low-cost cruise missile- approaching its target, the wing was to be jettisoned, hence the need for a parasol-type wing. The "B" version replaced the warhead section of the "A" version with a slightly bulged nose compartment that housed imaging sensors and datalinks to act as a reconnaissance UAV. The "B" version had a stalky retractable landing gear as well. The use of an inverted-V tail was to protect the pusher prop during landing and takeoff. By 1988, Amber had demonstrated a flight endurance of nearly 40 hours when competing companies were barely getting 12 hours out of their designs. Not only was Karem's design outflying its competitors, it was also proving to be immensely reliable as well. Thirteen Amber UAVs were built by 1990. 

In the same year that Amber was breaking records in 1988, Congress began to get impatient with the Pentagon's slow pace of UAV development. By 1990 the Pentagon was forced by Congressional mandate to consolidate the UAV research efforts of the different armed services into a single Joint Program Office (JPO). The JPO, however, wasn't budgeted any funds for research, which meant that only big defense contractors could stay in the running where internal corporate funding was plentiful. At the same time, and in its infinite wisdom, Congress banned DARPA from supporting UAV projects outside of the jurisdiction of the Pentagon JPO and as a result, Leading Systems' funding dried up overnight and Amber had to be canceled despite its achievements. 

Leading Systems/General Atomics Gnat 750

To try and stay afloat, Abraham Karem and his small team at Leading Systems developed a UAV based on Amber that was less-complex and used a standard Rotax piston engine for propulsion. This UAV was named the Gnat 750. Since the Gnat was planned for the export market, it was larger and didn't have as many of the advanced features of Amber, but it retained the overall layout with the difference that the wing was now directly attached to the fuselage instead of high-mounted on a pylon. The inverted-V tail was still there as well as a pusher prop and the stalky retractable undercarriage. The Gnat 750 first flew in 1989 and despite being "less high-tech" than Amber, boasted a significant number of design improvements. However, the loss of DARPA funding was too much for Leading Systems and Karem was looking at shutting down the company. However, San Diego-based defense contractor General Atomics was looking in 1990 to diversify its holdings outside of its core business of nuclear reactor technologies. One of its corporate directors was a former US Navy rear admiral, Thomas Cassidy, who joined General Atomics in 1987. He thought Karem's operation would be a good fit for what General Atomics was looking for and in 1990, General Atomics acquired Leading Systems and set up Abraham Karem and his team in a subsidiary General Atomics Aeronautical Systems to continue the development of the Gnat 750 UAV. 

In 1993, the Pentagon issued a requirement to rapidly field a surveillance UAV to support UN peacekeeping forces in the former Yugoslavia. The Gnat 750 was selected, but because the need was immediate and existing military acquisition procedures were too slow, the program was transferred to the CIA under the code name LOFTY VIEW. Since the CIA would be operating the Gnat 750 in secret, it fell outside of the purview of the Congressional mandate the created the UAV JPO that inadvertently killed off the Amber program. By 1994 the first Gnat 750s were deployed to a CIA operating base in Albania for operations throughout the Balkans. The UAVs provided overhead surveillance for UN convoys as well as spotting artillery emplacements and the operating locations of the various belligerents in the wars that wracked the region through the latter half of the 1990s. The bad weather of the Balkans and the limited range of the Gnat's datalink proved to be the main issues that affected operations. 

While the CIA was getting the Gnat 750 operational over the Balkans, General Atomics Aeronautical Systems had secured funding under an advanced concept technology program. At the time, UAV development had been stratified into "Tier" levels based on endurance and performance. I had reviewed these Tiers a year ago in a previous blog posting that covered the development of top-secret stealthy Quartz UAV: 

In the 1990s, there were three "tiers" of UAV development based on operational capability. "Tier I" was for a low-altitude system that became the Gnat-750 UAV. "Tier II" was for a more capable medium altitude system based on the Tier I craft and that became the current Predator UAV family. The specification for "Tier III" would have been filled by the Quartz project, but with its cancellation, Tier III was split into two- Tier II+ was for the Quartz's performance without stealth and this became the RQ-4 Global Hawk UAV. Tier III- ("Tier III Minus") was stealthy but without the performance and payload of Tier II+. This design became the RQ-3 DarkStar. DarkStar, a joint effort between Boeing and Lockheed, had little in common with Quartz and itself would be canceled in 1999 in favor of further development of the Global Hawk.

General Atomics RQ-1/MQ-1 Predator

The Pentagon was issuing contracts for UAVs at each Tier. General Atomics's funding was for development of a Tier II UAV. The new design took the Gnat 750 and stretched the fuselage and lengthened the wings. The inverted-V tail, stalky retractable undercarriage, and pusher prop were retained (though with a more powerful Rotax piston engine). Since one of the weaknesses of the Gnat 750 was the limited range of its datalink, the new UAV had an enlarged nose section that had the imaging payload on the underside of the nose similar to what the Gnat 750's layout, but incorporated a satellite communications dish in a bulged radome as the new datalink. Use of a satcom datalink now meant that the UAV operators and pilots didn't even have to be in the same region as the UAV's area of operations. It was now possible for the crews to fly the UAVs from stateside bases using the satcom datalinks to fly the Tier II UAV anywhere in the world it was needed. 

Named Predator, the new Tier II UAV made its first flight in June 1994. Less than a year later during the Roving Sands 95 exercise at Fort Bliss, Texas, the Predators were used for the first time in an operational demonstration. They were so successful at Roving Sands that year that the USAF established its first UAV squadron, the 11th Reconnaissance Squadron at Indian Springs Auxillary Airfield in Nevada (later renamed Creech AFB in 2005) shortly after the exercise in Texas and just one month after Roving Sands, the first Predators were deployed to the Balkans under Operation Nomad Vigil. From July to November that year the 11th RS operated its Predators out of Gjader in Albania in support of Operation Deliberate Force, the NATO air campaign against Bosnian Serb forces. While more capable than the Gnat 750s operated by the CIA, the need for overhead surveillance was so great in the Balkans that both the Predator and the Gnat 750s operated simultaneously in theater. 

By 2001, the USAF had taken delivery of 68 Predator UAVs. Due to the steep learning curve in operating such a radically different type of aircraft, 19 were lost, but only 4 were confirmed to have been shot down over the Balkans. But it was only the beginning of how the Predator began to change the way air campaigns were fought. And that is subject matter for a future posting on this blog!

Sources: Birds of Prey: Predators, Reapers and America's Newest UAVs in Combat by Bill Yenne. Specialty Press, 2010, p37-40.

 Popular Science, September 1994. "Drones: Invented and Forgotten" by Bill Sweetman, p34.

Designation-Systems.net by Andreas Parsch. "Leading Systems Amber" and "General Atomics Gnat".

Photos: Federation of American Scientists, United States Air Force.

Project Palladium: Testing Soviet Radars

The A-12 Cygnus flew mostly in bare titanium with few markings

When the Lockheed U-2 made its first overflight of the Soviet Union on 4 July 1956, it was common knowledge that its apparent invulnerability was time-limited as advances in Soviet air defense systems were sure to eventually bring one down. In fact, USAF analysts were in the planning stages of a replacement to the U-2 long before it even made its first flight. The first such study was for an exotic liquid hydrogen powered aircraft called Suntan from Lockheed which ended up getting canceled in 1959 at the urgings of its designer, the legendary Kelly Johnson. Running parallel to the Suntan which was an Air Force project, the CIA had two studies going for a U-2 replacement- one was a subsonic design code named Gusto and the other was a supersonic design that ultimately became Oxcart. That program's flying hardware was the Lockheed A-12 Cygnus, a single-seat predecessor to the two-seat SR-71 Blackbird. The A-12 made its maiden flight at Groom Lake/Area 51 on 26 April 1962, two years after Francis Gary Powers had been shot down over the Soviet Union in his U-2. 

A-12 landing at Groom Lake; note the single seat cockpit

The design of the A-12 was the first to take into consideration a reduction in radar cross section (RCS) to limit the detection range by an adversary's radar systems. On the Lockheed A-12, the leading edges of the wings and chines had pie-shaped wedges that were filled with a composite material that would theoretically reduce the RCS of the aircraft. With three A-12s in flight testing by October 1962 at Groom Lake/Area 51, the Cuban Missile Crisis took place- with the shoot-down of Major Rudolph Anderson and his U-2 by an SA-2 missile on 27 October 1962 in the midst of the crisis, the Oxcart project took added urgency and the need for operational Mach 3 strategic reconnaissance capability as soon as possible was deemed an urgent national priority. While the intensity of flight testing at Groom Lake picked up, a program was established to determine the A-12's detectability to Soviet radar systems. Two radar systems in particular were of interest to the CIA, the P-12 "Spoon Rest" radar which was used as a search radar for the SA-2 surface-to-air missile batteries and had a range of 100 miles, and the even more powerful P-14 "Tall King" radar which had double the power and range of the P-12 system. 

Soviet P-12 "Spoon Rest" radar

As part of a broad reaching program of electronic intelligence to support the A-12 Cygnus, a highly-classified program called Palladium was established to test the sensitivity of Soviet radars. Palladium was a special electronic transmitter that could project a false target into the "Tall King" and "Spoon Rest" radar systems. Technicians could adjust the Palladium signal to present varying targets of RCS values and with National Security Agency (NSA) technicians eavesdropping on communications channels, it became possible to find out what size RCS target the Soviet radar systems could acquire. During the 1962 Cuban Missile Crisis, nineteen SA-2 missile sites were constructed on the island supported by P-14 "Tall King" radars. Oxcart planners realized they had a unique opportunity to test the sensitivity of the latest in Soviet defense radars during the Crisis. 

Soviet P-12 "Tall King" radar

One night during the crisis a US Navy destroyer carrying the Palladium transmitter positioned itself north of Havana and used the CIA's special transmitter to project the signal of an aircraft racing south from NAS Key West towards the Cuban capital. At a predetermined time with a P-14 radar tracking the Palladium ghost target, a US Navy submarine surfaced just offshore of Havana and released a series of balloons, each carrying a radar reflector corresponding to a specific RCS value. The sudden appearance of multiple targets offshore then triggered the SA-2 operators to activate their fire control radars as well. With the NSA listening to Cuban and Soviet communications, it was possible to determine the smallest size RCS reflector that could be detected by both the P-14 search radar and the SA-2 batteries' fire control radars. Cuban MiGs were scrambled that night and it must have made for an interesting post-flight debrief when CIA technicians aboard the destroyer switched off the Palladium set, causing the targets to suddenly disappear. As a result of this unique test, it was determined that the RCS-reducing features of the A-12 Cygnus still made it detectable by not only the long range search radars, but also the fire control radars of the SA-2 missile batteries. Despite the findings of this unique and risky test given the tensions present during the crisis, the flight testing and operational deployment of the A-12 Cygnus continued. Its first operational recon missions over hostile territory took place in 1967 over North Vietnam. 

Source: Lockheed Blackbird: Beyond the Secret Missions by Paul Crickmore. Osprey Publishing, 2010, p16-45.

Francis Gary Powers: After the Return

On May 1, 1960 a lone CIA U-2 spyplane took off from a forward operating base in Peshawar, Pakistan for what would be one of the most fateful flights of the Cold War era. After over 5 years of uneventful US overflights of the Soviet Union, this mission, piloted by Francis Gary Powers, would change the strategic balance of the Cold War. Powers' mission was to take him on a marathon mission over several reconnaissance targets of interest, from the Baikonur missile test facility, the Sverdlosk industrial center, the ICBM bases at Plesetsk, the submarine construction yards at Severodvinsk, and the Soviet Northern Fleet base at Murmansk before recovering at the NATO base at Bodo, Norway. Halfway through his flight before reaching Sverdlosk at an altitude of 70,500 feet, an SA-2 surface-to-air missile exploded aft of his aircraft, sending it spiraling downward. Powers survived and was promptly apprehended by Soviet authorities and in one of the dramatic moments of the Cold War, was tried in the Hall of Columns at the Kremlin in a highly-publicized proceeding that began on August 17, 1960. He was sentenced to 10 years in prison for espionage.

For the next 18 months Powers was in prison, the US government negotiated for his release and settled upon a trade for convicted Soviet spy Rudolf Abel. Interestingly, the idea for the trade originated with Powers' father, Oliver. In November 1961 acting Director of Central Intelligence (DCI) Charles Cabell notified Secretary of State Dean Rusk of the CIA's support of a trade. On February 1962 following President Kennedy's final approval, at a bridge in Berlin that connected East and West sides of the city, Francis Gary Powers was traded for the spy Rudolf Abel. Powers was immediately flown back to the United States for a comprehensive debriefing, convening what the agency called a "damage assessment team" to determine what damage Powers' shootdown and subsequent interrogation/imprisonment had done to US airborne intelligence efforts. Considering that Powers was extensively involved with the U-2 program from its beginnings, it was assumed that he had revealed everything to the Soviets- instructions to U-2 pilots of what to do in case of capture was scant at best. They were advised to "tell everything since they're going to get it out of you anyway". Some pilots flew on Soviet overflights with cyanide capsules and Powers was given a poison-tipped needle to inject himself with in the event of capture, but it was seized from him when he was apprehended after bailing out. At any rate, after a two week debrief, the damage assessment team concluded that the damage was minimal and were very satisfied with Powers' efforts to reveal as little classified information on the U-2 program as possible.

This wasn't sufficient for the newly-appointed DCI, John A. McCone (the previous appointed DCI was Allen Dulles who resigned in November 1961 in the wake of the shootdown and the failed Bay of Pigs invasion) demanded a further examination of Powers' actions while in Soviet custody despite a letter of support from the previous DCI, Allen Dulles. A new board of inquiry headed by federal judge Barrett Prettyman was convened to investigate the matter further. Testimony from the agency experts who debriefed him was taken, a thorough examination of Powers' background from his doctors to his fellow pilots and commanders from his former Air Force units was performed as well as a voluntary polygraph examination of Powers himself. Soviet photographs taken of the U-2 wreckage were reviewed by Lockheed Skunk Works engineer Kelly Johnson (who designed the U-2) and he found them consistent with Powers' story. DCI McCone was unconvinced and ordered the Air Force to have its own panel of experts review the evidence. The US Air Force echoed the Prettyman Board's findings as well with DCI McCone having only a possible procedural error by Powers in maintaining his course/altitude as the only bit of information contrary to Powers' testimony.

DCI McCone ordered the Prettyman Board reconvened to re-examine the evidence but their second report remained essentially unchanged from their original findings. In March 1962 Powers himself testified before the Senate Armed Services Committee who commended his actions and conduct during the mission and his subsequent capture. Despite all this, any findings that exonerated Powers weren't released to the public and the sensationalized press of the day resulted in a very negative portrayal of Francis Gary Powers. With no public statements from government officials commending Powers for his efforts to withhold classified information from the Soviets during his 18 month internment, in the public eye his motives and loyalties were questioned. His 1962 divorce from his wife further stained his reputation in the press. Powers was snubbed by President Kennedy who had already warmly received other pilots who had been shot down and captured by the Soviets and in 1963 DCI McCone awarded the CIA Intelligence Star to all the Soviet overflight U-2 pilots except Powers (It wasn't until 1965 that Powers got the Intelligence Star from McCone's successor).

CIA U-2 pilots were all drawn from USAF units with the agreement that they would temporarily be on leave from the Air Force for their tour of duty with the CIA, after which they could return to the USAF unit and active duty. Though there was significant initial opposition to his reinstatement with the Air Force, it was approved pending the conclusion of all the investigative proceedings. In the interim time, Kelly Johnson hired him as a U-2 test pilot at Lockheed in support of upgrades and developments being worked on for future U-2 versions. In late 1963 he was offered a chance to return to the Air Force, but Powers elected to remain at Lockheed working for Kelly Johnson. In 1969, with the end of U-2 production work, Kelly Johnson reluctantly had to furlough Powers as Lockheed was unable to place Powers in any other programs. Kelly Johnson would write in his test logs "I must let Gary Powers go. I have protected him for about seven years..."

Powers subsequently found work flying for a Los Angeles radio station as a traffic reporter and subsequently went to work for KNBC as a helicopter pilot. On August 1, 1977, Powers and his cameraman, George Spears were flying back to the KNBC heliport in Burbank in a Bell Jet Ranger 206 after covering a brush fire in Santa Barbara, when for reasons unknown, the helicopter ran out of fuel and crashed near the Sepulveda Dam in the San Fernando Valley community of Encino. Powers and Spears were killed instantly. Powers was laid to rest with honors at Arlington National Cemetery. On May 1, 2000, on the 40th Anniversary of his shootdown, USAF and CIA officials posthumously awarded Francis Gary Powers the Prisoner-of-War Medal, the Distinguished Flying Cross and the National Defense Service Medal. The ceremony with Powers' family took place at Beale AFB, home of the 9th Reconnaissance Wing which today still operates the U-2. At the conclusion of the ceremony, a lone U-2 made a low-level flyby.

Powers' shootdown in 1960 marked the first time a surface-to-air missile successfully brought down a hostile aircraft and his overflight would be last US overflight of the Soviet Union. The Soviet Union would go on to develop one the most comprehensive air-defense systems in the world and that would dictate US strategic planning well into the 1990s with a shift towards low-level penetration bombers, stealth, and most importantly, the technological shift to relying on satellites to provided imagery of Soviet installations and activities.

Source: Spyplane: The U-2 History by Norman Palomar. Zenith Press, 2001.

Tabasco/Purple Flash: Sensor Pods Delivered by U-2 Spyplanes

Last month I had posted about Steel Eagle, a modern-day counterpart to the Igloo White acoustic/seismic sensors dropped on the Ho Chi Minh Trail during the Vietnam War. The use of such remote-sensing pods that embedded themselves in the ground after being dropped by an aircraft weren't just limited to tactical use- a similar program was under taken in the 1960s called Tabasco (the unclassfied project name was Purple Flash) to drop sensor pods from Lockheed U-2 spyplanes flying some of the longest range flights in the aircraft's history over the Chinese nuclear tests sites at Lop Nor, deep in the desert basins of northwest China.

Corona satellite imagery detailed the Lop Nor installation ever since the first Chinese nuclear detonation in 1964 caught Western scientists off guard. The Department of Energy's Sandia Labs in Albuquerque had been working on adapting US seismic equipment used to analyze nuclear tests in Nevada to fit into the air-dropped pods that weighed 285 lbs. The pods were carried under the U-2 wing and a parachute deployed after the drop to slow the pod just enough to not damage the sensors but allow the spike-shaped pod to embed itself in the ground. Once on the ground, a 10-foot telescopic antenna deployed to transmit data to listening posts on the periphery of the People's Republic of China.

On 29 April 1966 the first prototype pod was dropped over the White Sands Missile Range from a U-2 and landed only 800 feet from the target but the sensors were damaged. While the design was being reworked by Sandia, Lockheed and the CIA embarked on a series of long-range flights to see just how much range they could get out of the U-2 to demonstrate the Lop Nor site could be reached from Takhili AB in Thailand.

By 1967 Taiwanese pilots with the RoCAF were training in the United States for the Tabasco flights. On 7 May 1967 the first operational Tabasco mission successfully dropped two sensor pods at Lop Nor, but for whatever reason, no signal was received from them. Another Chinese nuclear test took place that June while the CIA was still trying to interrogate the sensor pods in the desert. Needless to say, it was frustrating for intelligence officials. It was concluded the only way to know for sure was to send another U-2 flight to Lop Nor carrying interrogation equipment to try and activate the pods. On 31 August 1967 another RoCAF pilot took a U-2 to Lop Nor and was nearly ambushed by a salvo of SAMs but no signal was received from the pods.

After two high-risk flights, a second set of Tabasco pods were dropped at Lop Nor, this time by a Lockheed C-130 flown by Taiwanese pilots flying at low level. The outcome of that mission remains classified. After the second Lop Nor mission, the six year program of overflights of the People's Republic of China by the Taiwanese pilots of the "Black Cat" squadron came to an end as improved defenses made further flights too risky.

Source: 50 Years of the U-2: The Complete Illustrated History of the "Dragon Lady" by Chris Pocock. Schiffer Publishing, 2005, p246-252.

In an earlier entry I had featured the RB-69 spyplane conversion of the Lockheed P2V Neptune that was the Skunk Work's first CIA contract. That CIA program to operate low-altitude overflights of the People's Republic of China starting in 1957 was codenamed ST/POLLY by the CIA. The program had generated much useful intelligence on the military activities of the the PRC that the CIA contracted with E-Systems of Greenville, Texas, to convert three Lockheed P-3A Orions to a similar configuration but with more intelligence-gathering systems under the codename ST/SPIN, starting with the arrival of the first P-3A to the naval aviation depot in Alameda, California where E-Systems began the conversion work.

The most obvious modification (apart from its all black color and abbreviated tail sting as the MAD sensor wasn't needed on the clandestine overflights) was a widening of the crew entry door on the aft fuselage with a duplicate door right next to the existing door- this gave a just over six foot wide entry with two inward-opening doors- like the earlier RB-69 Neptunes, this was to allow the infiltration of field agents, special equipment, arms and ammunition and on occasion, propaganda leaflets by the boxload.

The ELINT receivers from the RB-69 Neptunes were taken out, upgraded, and installed on the ST/SPIN Orions. Additional sensors were added thanks to the increased performance of the Orion over the Neptune- a SLAR was added for peripheral reconnaissance missions along the Chinese border, communications intercept equipment, an infrared detector and allegedly even a sensitive acoustic detector. Slant-range and oblique photography cameras were also installed and to also perform intelligence on the Chinese nuclear program, air-sampling equipment was also installed connected to ram air scoops near the cockpit.

The first ST/SPIN operational mission took place in 1964. All the personnel aboard the aircraft were Taiwanese trained and led by the CIA. Missions ranged from gathering radar ELINT data for the Strategic Air Command to even flights into Tibet to gather information on the PRC's suppression of Tibetan nationalists.

However, the Taiwanese general running the program would staff each plane with as many as 27 crew when only 13 to 14 were needed. Taiwanese personnel got a bonus for flying on ST/SPIN missions and he was taking a kickback to assign extra crew to each mission. Operatives of the PRC were able to penetrate the ST/SPIN program to the point that during an ST/SPIN mission, PRC radio operators would call out the aircraft and ask to speak to specific crewman by name.

By 1965 the Taiwanese general was arrested and sent to prison for his staffing scheme and the CIA and NRO (National Reconnaissance Office) withdrew funding from the ST/SPIN program before the third P-3A Orion could be completed. The aircraft were returned to the United States.

Source: Wizards of Langley: Inside the CIA's Directorate of Science and Technology by Jeffrey Richelson. Westview Press, 2002, p96-98.

The Lockheed SR-71 Blackbird's first operational mission took place on 21 March 1968 out of what was designated OL-8 (Operating Location 8) which was Kadena AB on the Japanese island of Okinawa. The 9th Strategic Reconnaissance Wing of Beale AFB, California, had just been formed two years prior to bring the two-seat Mach 3 spyplane into service. For several years prior to the Blackbird's entry into service, the CIA had been operating its single seat predecessor, the A-12, which had the code name "Oxcart" and this particular variant was retired in the same year that the SR-71 became operational.

Though the A-12 in CIA hands had made several overflights of North Vietnam in support of the war effort in Southeast Asia (the first flight having been made to see if North Vietnam did have any surface to surface short range ballistic missiles, which they didn't), the first SR-71 operational mission would fly over North Vietnam on a similar routing as the CIA flights just 10 months earlier. With Major Jerry O'Malley flying and Captain Ed Payne as his RSO (Recon Systems Operator), the Blackbird's first mission not only carried a battery of optical cameras but also a side-looking radar (SLAR) in the nose bay. After making their first run across North Vietnam, the SR-71 crew conducted an airborne refueling over the South China Sea before accelerating back to Mach 3 for a second run, this time over the DMZ area. On this second run, the SLAR would be the primary instrument.

Although the flight had to abort landing at Kadena due to weather and instead diverted to Taiwan, the high-definition SLAR imagery around the Marine Corps base at Khe Sanh which was under siege at the time revealed numerous artillery emplacements and a large supporting truck park that had eluded the optical sensors of other reconnaissance aircraft. Within a few days of that first operational mission, US aircraft targeted the artillery emplacements and staging areas uncovered by the SR-71 SLAR run and effectively broke the 77-day siege of Khe Sanh. Both Major O'Malley and Captain Payne were awarded the Distinguished Flying Cross for their flight that was instrumental in saving Khe Sanh.

Source: Wings of Fame, Volume 8. "Lockheed's Blackbirds: A-12, YF-12 and SR-71" by Paul Crickmore. Aerospace Publishing, 1997, p61-64.

The Most Ambitious UAV Ever: Quartz/AARS

One of the most ambitious if not the most expensive UAV design effort came in the 1980s as the Cold War was coming to its climax. Over $1 billion was spent on a black project called the AARS- Advanced Airborne Reconnaissance System or known by its code name, Quartz. The Quartz UAV was designed to be a very stealthy, long-endurance UAV that would penetrate Soviet air space in a time of war and identify what were called "strategic relocatable targets"- the rail- and road-mobile ICBMs of the Soviet's Strategic Rocket Forces. Quartz was sponsored by the US Air Force and the NRO, National Reconnaissance Office.

The requirement for a 24-hour endurance and low-observability tested the limits of aerospace technology of the day. In 1983 Lockheed and Boeing were selected to develop concepts for the Quartz program. Lockheed's initial design was a giant aircraft with a 267-foot wingspan propelled by two turboshaft engines driving massive 47-foot propellers. The engines were actually dual-cycle turboshaft/turbojet engines, with the engines operating as jets and the two-bladed props locked in horizontal for takeoff and landing. Once at cruise altitude, the engines shifted into turboshaft mode to drive the large props.

Little is known of Boeing's design for Quartz other than it may have been a flying wing design along the same lines as the Lockheed proposals. The need for low-observability and autonomous operation in denied airspace resulted in an expensive design that was compounded by the fact that only a few Quartz UAVs would be needed- the technology used was so sensitive that only the strategic imperative made it worth the risk of losing the aircraft in the event of malfunction or shootdown.

As the costs of the program soared, it became a victim of an inter-agency squabble between the CIA and the NRO who wanted Quartz and the USAF, who was losing interest due to the rising costs. In 1990 Lockheed and Boeing were directed to combine their efforts which resulted in a jet-powered flying wing not too dissimilar from the Northrop B-2 Spirit stealth bomber. As the costs still continued to climb, the USAF continued to back away from the program and even a redesign for a slightly smaller version failed to bring the USAF back aboard. Quartz was cancelled in 1992 when the NRO finally withdrew from the program as well.

In the 1990s, there were three "tiers" of UAV development based on operational capability. "Tier I" was for a low-altitude system that became the Gnat-750 UAV. "Tier II" was for a more capable medium altitude system based on the Tier I craft and that became the current Predator UAV family. The specification for "Tier III" would have been filled by the Quartz project, but with its cancellation, Tier III was split into two- Tier II+ was for the Quartz's performance without stealth and this became the RQ-4 Global Hawk UAV. Tier III- ("Tier III Minus") was stealthy but without the performance and payload of Tier II+. This design became the RQ-3 DarkStar. DarkStar, a joint effort between Boeing and Lockheed, had little in common with Quartz and itself would be canceled in 1999 in favor of further development of the Global Hawk.

However, it's believed that the current Lockheed/Boeing proposals for a next-generation bomber (the picture included in this blog post) are nearly identical save the cockpit to the resultant Quartz design.

Source: International Air Power Review, Volume 15. AIRtime Publishing, 2005, "Focus Aircraft: HALE/MALE Unmanned Air Vehicles Part 1: History of the Endurance UAV" by Bill Sweetman, p63-69.

In the 1950s the United States introduced three different systems to try and solve the problem of conducting electronic intelligence (ELINT) on targets deep in the Soviet Union which couldn't be picked up by the USAF and Navy ferret flights operating on the periphery. The first system was to mount ELINT antennas on giant weather balloons that would be launched in Western Europe and drift over the Soviet Union on prevailing winds before being recovered out in the North Pacific. Approximately 200 "Grand Union" balloons were built for the USAF and only about 20 were actually launched with little to no useful intelligence being recovered. The second system was to use ELINT antennas mounted on Lockheed U-2 spyplanes during overflights of the Soviet Union. Between 1956 and 1959, approximately 30 ELINT overflights were made, but only a handful of those missions were deep penetration missions.

The most productive of the systems and ironically the lowest risk due to its low manpower requirement as well as it could be located in the United States was introduced in 1958 as the PAMOR (Passive Moon Relay) system. Originating from experiments dating back to 1948's Project Diana which determined that communications signals could be bounced off the Moon to receivers beyond the horizon, PAMOR (sometimes referred to Moonbounce) was the natural extension. A CIA engineer, Jim Trexler, postulated that a sensitive receiver pointed at the Moon could pick up radar emissions from sites deep in the Soviet Union.

The first PAMOR dishes were built at the Naval Research Laboratory's Chesapeake Bay Annex on the bay's western shore as well as in California in Palo Alto. The definitive equipment was installed soon after in a valley near Sugar Grove, West Virginia (not far from the radio astronomy observatory at Green Bank). Using 150-foot dishes and sensitive listening and tracking equipment, the system readily produced results as the new early warning radar system code named "Tall King" was discovered. Designated P-14 by the Russians, the Tall King radar was a powerful system used for the detection and tracking at long ranges of airborne aircraft. Using known Moonrise and Moonset times, it was possible to draw a line on a map through the Soviet Union- somewhere along that line would be the transmitting radar. Over several weeks, it was possible to narrow down the precise location as this would be where the Moonrise/Moonset lines intersected.

In the latter half of the 1960s (starting in 1964 when it was first intercepted by a PAMOR dish), the system discovered a new high power advanced radar system that was found to be used by the Soviet ABM system to scan and track incoming ballistic missile warheads. Code named "Hen House" due to the configuration of the antenna, detailed analysis not only revealed the Hen House locations, but also radar characteristics such as frequency, power, dwell time, etc. From this analysis it was determined that the Hen House radar was very sophisticated as it could both track and scan and its dwell times were very short, which suggested a high level of computerization.

As the Soviets upgraded and fine-tuned the Hen House system for its ABM defenses, operators would practice and test the system by tracking the Moon, inadvertently making the job of the PAMOR teams much easier!

The discovery by the PAMOR program of the Hen House ABM system was significant as the characteristics of the system drove the design and planned employment of the US SLBM/ICBM nuclear deterrent. At its height in the late 1960s and early 1970s, the program never employed more than 100 personnel, making it one of the most successful ELINT efforts ever deployed.

Source: The History of U.S. Electronic Warfare, Volume II- The Renaissance Years, 1946-1964 by Alfred Price. The Association of Old Crows/Port City Press, 1989, p157-161.

During the design of the first Lockheed U-2 spyplanes, designer Kelly Johnson held fast to his rule "one pound equals one foot of altitude" and if it wasn't completely necessary to the mission, it wasn't going on the aircraft. As a result, many of the navigational aids considered standard on most military aircraft were absent on the U-2. Central to the U-2's navigation equipment was the driftsight- a downward looking periscope that had two selectable magnifications. The circular driftsight dominated the center of the instrument panel on the U-2 until its replacement by GPS and glass displays in the 1990s. The driftsight give the pilot a 360-degree view underneath the aircraft and it was used for navigation in addition to sighting for the cameras.

If the ground wasn't visible due to overcast, dead reckoning was also used since the winds at the altitudes the U-2 operated were usually very light. The aircraft did have a radio compass, the AN/ARN-6, but on deep penetration flights of the Soviet Union, radio stations were far and few between.

A HF antenna system was planned for the U-2, allowing the pilot to tune into HF ground stations and determine his position by triangulation. Though tested successfully, the CIA realized that HF transmissions could betray the aircraft's position and the system, called System II, was dropped from the design.

The solution was to use the driftsight in combination with a specially-made sextant that was aligned with the driftsight's optical path. A mirror could be switched that diverted the view through the optical driftsight to the sextant unit that was mounted just ahead of the cockpit atop the nose. At the 50,000+ feet altitudes the U-2 operated, the sky was black as night even in midday and star fixes could be taken using the sextant coupled to the driftsight. Since the fully suited pilot wouldn't be able to compute the star fixes and positions during the mission, an essential crewmember to each U-2 mission was a flight-rated navigator who planned the star fixes and did all the calculations ahead of each mission. As the calculations were specific for a particular timeframe, it was essential that the U-2 takeoff within a prescribed window of time or the star fixes would have to be recalculated by the navigator.

Source: 50 Years of the U-2: The Complete Illustrated History of the "Dragon Lady" by Chris Pocock. Schiffer Publishing, 2005, p32.

In the summer of 1967, the USAF was conducting a captive carry flight of the Lockheed D-21 reconnaissance drone over Nevada when a damaged attachment bolt in the B-52's pylon that held the D-21 sheared, resulting in the drone and its booster rocket dropping away. The automatic start sequence of the D-21 began and the booster rocket ignited, accelerating the D-21 away. Since the inertial navigation system hadn't been programmed, the D-21 flew unguided until it crashed in the Railroad Valley outside of Area 51.

A local rancher and his wife came upon the scene and took several pictures. Once the Air Force had arrived on scene, as much of the still top secret drone's wreckage was collected and spirited off back to Area 51. The USAF/CIA officer in charge of the clean up, Col. Frank Hartley, found out about the rancher's pictures and not wanting to intimidate the rancher into giving up the photos, he instead asked him if there was anything he wanted in exchange for the film. The rancher told Hartley he had a "hankering" for some cream pie. Hartley made some phone calls to Area 51 and soon a helicopter arrived with a fresh cream pie and Col. Hartley got the film in exchange.

Source: X-Plane Crashes: Exploring Experimental Rocket Plane, and Spycraft Incidents, Accidents, and Crash Sites by Peter W. Merlin and Tony Moore. Specialty Press, 2008, p99.

The first Lockheed Skunk Works contract with the CIA wasn't the U-2 spyplane, but a spyplane adaptation of the Lockheed P2V Neptune maritime patrol aircraft. Predating the U-2 contract by several months, seven P2V-7 Neptunes were modified by Kelly Johnson's team into RB-69s. The aircraft were equipped with the first operational terrain avoidance radar (built by Texas Instruments), doppler navigation radars, a variety of ECM equipment, and in later years a large General Electric SLAR unit in a housing on the right side of the aft fuselage.

The first missions assigned to the RB-69s were the mapping of the Russian power grid in Eastern Europe. Missions were flown out of Wiesbaden AB in West Germany in 1955-1956. Beginning in 1957, missions were also flown over China from bases in Taiwan, usually with Taiwanese crews and markings.

Source: Lockheed Secret Projects: Inside the Skunk Works by Dennis Jenkins. MBI Publishing, 2001, p29.