The American V-1 Program 1944-1950

Beginning in 1942, Allied intelligence began a systematic analysis of the Fiesler Fi 103 flying bomb better known as the V-1. Analysis of crashed test articles combined with photoreconnaissance and intelligence collected by agents within occupied Europe led the United States in particular to restart its flying bomb programs in 1943 that had laid dormant for the most of the Second World War on account of what was felt to be beyond the current state of the art. In 1944, Northrop was contracted to begin development of the first US flying bomb, designated the JB-1. Running parallel to the Northrop effort was the reverse-engineering of the V-1 using 2,500 lbs of salvaged V-1 parts that had been provided by Great Britain. The parts arrived at Wright-Patterson Field in Dayton, Ohio, on 13 July 1944 and the US Army Air Forces directed the engineering staff there to build 13 copies of the V-1. Quite remarkably, the USAAF technical staff completed the first copy in just three weeks! To put the scope of the success of the Allied intelligence effort and the work the Wright-Patterson Field team into perspective, the first German V-1s struck Britain on 12-13 June 1944. By the end of the following month, the USAAF had its first copy of the V-1 and they had test fired the reverse-engineered pulse jet engine. A memo from the technical team responsible to General Henry Arnold, head of the USAAF, recommended mass production at the earliest opportunity- however, General Arnold and his advisors were well aware of the V-1's inaccuracy and despite reservations that production of an American V-1 would divert crucial wartime resources and manpower from battle-proven weapons, it was felt that if the guidance of the V-1 could be improved, an American version might be useful. 

The Republic-Ford JB-2 differed from the V-1 in minor details
(USAF/Wikipedia)

Republic Aviation was tasked with producing the American V-1 which was designated JB-2 with the first of the thirteen USAAF copies arriving on 8 September 1944 from Wright-Patterson Field. The USAAF ordered 1,000 JB-2s from Republic. The Ford Motor Company was tasked with producing the JB-2's pulse jet engine which was designated the PJ31. With Republic's resources nearly all committed to the production of the P-47 Thunderbolt, the company subcontracted the airframe assembly to Willys-Overland, the same company that built the Jeep. With Ford responsible for engine production, the Jack & Heintz Company of Cleveland which had been building aircraft electrical components and autopilots as a subcontractor was given responsibility for the JB-2's control system. Alloy Products of Wisconsin was given responsibility for the fuel tanks and pressure vessels used in the JB-2 while the Northrop was contracted for the JB-2's launch sled. The booster rockets that actually propelled the JB-2 off the ground were contracted to Monsanto. 

By the end of September 1944, the USAAF revised its initial order for 1,000 JB-2s to 1,000 JB-2s *per* month with a target goal to reach that rate by April 1945. The first JB-2 launch took place at Eglin Airfield in Florida on 12 October 1944- just three months had elapsed since start of the German V-1 campaign against London and the first American copy had made its first flight! Flight testing was also carried out at Wendover Field in Utah at the same time that the B-29 Superfortress unit that dropped the atomic bombs, the 509th Composite Group, was a tenant at Wendover training for their special mission. The flight tests didn't go too smoothy- by the first week of December, there were two successful flights out of ten launches. 

JB-2 air launch from a B-17 at Eglin Army Air Field in 1944
(USAF/Wikipedia)

Northrop's own flying bomb design, the JB-1, made its first launch in December 1944 but crashed after launch. (The JB-1 will be the subject of its own later article here at Tails Through Time.) With the the early failures of the JB-1 and problems with its jet powerplant, the USAAF decided to continue with the development of the Northrop design but production and operational priority went to the JB-2. Despite issues with accuracy in the flight tests at Eglin and Wendover, the USAAF leadership pushed for an increased production rate for the JB-2 to at least 3,000 per month. On 14 January 1945, General Arnold ordered another 75,000 JB-2s with the ability to launch 100 per day by September and 500 per day by January 1946 in anticipate of the invasion of Japan. On the next day, the JB-2 program got the same priority that was given to the B-29 Superfortress program. 

Despite the enthusiasm from the USAAF leadership, theater and operational commanders were skeptical of the JB-2. The generally poor European weather that was interfering with the strategic bombing campaign, however, offered perhaps some utility for the JB-2 as it wasn't dependent on clear weather- a view supported by Sir Trafford Leigh-Mallory, the head of the Royal Air Force and commander-in-chief of Allied air forces for the Normandy invasion as well as General Carl Spaatz, head of US Strategic Air Forces Europe. Spaatz, however, was a bit more measured in his support for the employment of the JB-2. He felt that it was more a harassment weapon that could be used when bad weather precluded a strategic bombing mission and outlined his planned use at 300 JB-2s per day only 10 days out of the month. But General Spaatz was very specific that operational employment of the JB-2 could not interfere with heavy bomber operations and he personally expressed concerns to General Arnold regarding the JB-2's cost-effectiveness given its inaccuracy. 

The JB-2 flight test program centered primarily on improving the weapon's accuracy. The first successful flights in the fall of 1944 showed an average error of eight miles at a range of just over 120 miles, not much better than what the Germans were averaging in their own V-1 campaign. The next step by the USAAF was to install radio guidance control in the JB-2. Using a radar beacon and remote control, it was thought the JB-2's accuracy could be improved. However, continued flight tests showed in 20 flight tests with the new guidance system, the JB-2's average error was no better than it was before with preset controls. Things did get better though- by war's end, the JB-2 with preset controls was averaging 5 miles error over a range of 150 miles and 1/4 mile error over a range of 100 miles with radio guidance. 

The biggest stumbling block to the operational deployment of the JB-2 in Europe in 1945, believe it or not, was logistical. The sheer numbers of JB-2s needed competed with other munitions production and it was estimated by some in the War Department that just transporting the JB-2 and its associated equipment to Europe would take up nearly 25% of Allied shipping capacity in the Atlantic. Brief consideration was given to moving JB-2 production to Europe, but there simply wasn't the production capacity anywhere else but the United States to produce the numbers of JB-2s planners envisioned using. 

With the end of the war in Europe, JB-2 production numbers remained in flux as planners debated what was needed for the planned invasion of Japan. By this point, however, the production and logistical concerns for the mass deployment of the JB-2 had exhausted the initial enthusiasm for the weapon. Production was halted initially at the end of January 1945 but then reinstated at a lower rate. By the time of the Japanese surrender, 1,385 JB-2s had been built when production was terminated.

Concurrent with the USAAF testing, the US Navy worked on a navalized version of the JB-2 that would have been launched from specially-modified LSTs and escort carriers during the invasion of Japan. Fifty-one JB-2s were requested by the Navy for its own testing program in September 1944 when production was launched. While airborne launches from B-17 Flying Fortresses were done during testing at Eglin Field, the Navy planned to launch JB-2s from Consolidated PB4Y Privateers as well. Navy planners, however, didn't expect operational capability with the JB-2 (which was called the Loon by the Navy) until August or September 1946. The first Navy Loon launch was on 7 January 1946 with the Secretary of the Navy approving the conversion of two submarines for Loon operations in March 1946. Conversion of the USS Cusk (SS-348) began in January 1947. The Cusk entered the history books on 18 February 1947 as the world's first missile submarine when it made its first Loon launch...which ended in failure after only 3.5 miles of flight. The Cusk finally had its first successful launch on 7 March 1947 after five tries. Submarine launch had become the Navy's focus for the Loon program with the USS Carbonero (SS-337) also modified for the program and by 1949 finally carried out a firing from a surface ship, the test ship USS Norton Sound. In March 1950, the Navy terminated in the Loon in favor of the more promising Regulus cruise missile. 

The USS Cusk fires a JB-2 Loon
(US Navy/Wikipedia)

With the US Air Force becoming independent in 1947, the JB-2 program was reactivated in March 1948 at Holloman AFB in New Mexico as part of a program for the development of missile guidance systems and seeker technology. Work using the JB-2 benefitted the later Matador cruise missile program with the JB-2 program winding down by 1949 with test airframes successfully being flown remotely and skid landed for recovery. A joint effort with Eglin AFB also used the JB-2 as a target drone for the development of gunsights. Interestingly "Flakzielgerät 76" was the German cover name for the V-1 during its development which loosely translates as anti-aircraft target device.

Further reading:

British Defenses Against the Summer 1944 V-1 Bombardment
Regulus: The US Navy's First Operational Nuclear Missile
CHECK SIX: Ships Damaged or Sunk by the Yokosuka MXY7 Ohka

Sources: The Evolution of the Cruise Missile: Comprehensive History from the V-1 and V-2 to the Tomahawk and Snark by Kenneth P. Werrell. Air University Press/USAF, 1983, pp 79-85. V-1 Flying Bomb 1942-1952: Hitler's Infamous Doodlebug (New Vanguard No. 106) by Steven J. Zaloga. Osprey Publishing, 2005, pp 39-41.

The End of the Line for Curtiss Aircraft

XP-87 Blackhawk prototype
(USAF Museum)

In the summer of 1945 the US Army Air Force was in the process of outlining its combat aircraft needs in the post-war world. For fighter aircraft, there were three classes of aircraft that the USAAF wanted- an all-weather offensive fighter, a point-defense interceptor, and a long-range penetration fighter. It was expected that because of the state of the technology of the day that the all-weather offensive fighter would be the biggest of the three. On 28 August 1945 the USAAF issued its RfP (Request for Proposals) for the all-weather offensive fighter- a speed of 525 mph at 35,000 feet, 12 minutes to reach 35,000 feet and a 600-mile combat radius. It was thought at the time that piston engines would be necessary, but a refinement of the USAAF requirements a few months later laid out the service's desire for an aircraft that could seek out and destroy both enemy aircraft and ground targets in all weather conditions, day or night. Bell, Consolidated (Convair), Curtiss, Douglas, Goodyear, and Northrop submitted entries; Bell, Convair, and Goodyear were eliminated quickly due to performance deficiencies. Curtiss submitted a large four jet design based on the XA-43 attack jet design they had been working on for a different ground attack specification. Douglas submitted a land-based version of their F3D Skyknight, and Northrop submitted three designs- a refined version of the P-61 Black Widow, one based on the XP-79 flying wing fighter, and an all-new twinjet design. 

The political winds of change meant that the USAAF favored Curtiss heavily for the reasons that the previously dominant aircraft manufacturer had no contracts to sustain it in the postwar period and no civilian designs readily available for the growing passenger market. What was left of the funding for the XA-43 project was used to contract with Curtiss for prototypes of their design to be designated the XP-87. But the USAAF was sufficiently interested in Northrop's all-new twinjet design to contract for prototypes of that design as well to be designated XP-89. The USAAF also contracted with Martin Aircraft for a nose mounted turret that would allow the cannons to be swiveled to off-center targets that was to be fitted to both the XP-87 and XP-89. 

The XA-43. Note the differences from the XP-87 design.
(The Unwanted Blog at up-ship.com)

The designation XA-43 is often and mistakenly used interchangeably with the XP-87 designation- they were in fact two different aircraft that only resembled each other in basic layout. The XA-43 had a tandem cockpit, oval cross-section nacelles that were mounted inline with the wing, and was 65% larger than the XP-87 which had a side-by-side cockpit, rectangular nacelles under the wing. The XA-43's horizontal tail was low set and the design also featured a tail gun. The fact that the first XP-87 prototype was contracted with XA-43 funding led to the confusion that still is seen to this day. The XA-43 was ordered in November 1944 for a jet-powered ground attack bomber but it soon outgrew its proposed powerplants. By the time of the all-weather fighter RfP, the USAAF had lost interest in the XA-43 and allowed Curtiss to redirect its XA-43 efforts to the XP-87. But since policy of the time dictated two prototype aircraft in case of the loss of one, the original XA-43 contract was amended to allow for the construction of a second XP-87 prototype. In August 1946 Curtiss requested to name the XP-87 the Bat, but as there was already a US Navy glide bomb called the Bat, the request was turned down and a month later the XP-87 was given the name Blackhawk. 

By 1947 a review was underway to determine which of the fighters under development at the time might be suitable as a tactical reconnaissance aircraft- due to the size and carrying capacity of the XP-87, it was decided that it would also be developed into a reconnaissance version designated the RP-87. In order to not slow down the development, Curtiss was to complete both prototypes as all-weather fighters and then convert the second aircraft into the reconnaissance configuration at the completion of the prototype flight tests. In June 1947 Curtiss raised concerns with the USAAF on the power output of using four Westinghouse J34 engines in the paired nacelles and suggested changing to the Allison J33 as a single J33 engine had the power of two J34s not to mention the simplification of maintenance having only two engines instead of four. The change was approved for the production model but the prototypes would be completed with the four J34 engines. 

Only the XP-87 prototypes were to have four paired engines
(USAF Museum)

The first prototype was built at Curtiss' production facility in Columbus, Ohio, that once housed wartime production of the SB2C Helldiver. Taxi testing and ground tests took place at Columbus, but the USAAF wanted all flight testing to occur at Muroc AAF (later renamed Edwards AFB) in California. The first XP-87 was partially disassembled and loaded onto a trailer for transport to California- on going under the first highway overpass near the Columbus plant, the height was misjudged and the vertical fin hit the overpass, resulting in significant damage. With the damaged fin removed, he convoy headed out again and outside of Tulsa, Oklahoma got into an accident that damaged the nacelle for the left two engines. It was felt repairs could be made at Muroc and after month, the convoy reached the base where a new vertical fin and a team of  engineers were waiting to repair the prototype. The first flight was finally made on 1 March 1948 on a reasonably uneventful 58-minute maiden flight. The next several flights discovered buffeting in the tail due to it having a lower critical Mach number than the rest of the aircraft. Curtiss proposed a redesigned swept empennage for the production aircraft that was also duly approved by the USAAF. A total of 55 contractor test flights were made with the Blackhawk prototype and the flights confirmed the need to change to the Allison J33 on the production fighter- the Westinghouse J34s were unreliable and needed constant repair and replacement. By the time of the next series of flights with service test pilots, the USAAF was now the US Air Force and the first USAF flights were made on 3 June 1948. A week later the USAF placed a preliminary order for 57 P-87B Blackhawks (J33 engines and swept empennage were features of the production "B" version) and 30 RP-87B photo-recon aircraft. The following day the USAF switched from P-for-pursuit to F-for-fighter, the Blackhawk becoming the XF-87.

The now-designated XF-87 from the rear
(USAF Museum)

After 19 USAF test flights, a recommendation was made to Curtiss for a slightly larger wing to help reduce the stall speed and it was agreed that the second prototype XF-87 under construction would have the larger wing, the J33 engines, the swept empennage and reconnaissance modifications and would be designated XF-87C. In October 1948 the USAF held a fly-off evaluation with the XF-87 Blackhawk prototype, the Northrop XF-89 which got the name Scorpion, and a borrowed Navy F3D Skyknight to represent the Douglas submission as it was felt the Douglas design was close enough to the production Skyknight that it could act as a stand-in. With pilots of the Air Defense Command participating, while the XF-87 Blackhawk and F3D Skyknight had their strong points (side-by-side seating being one of the strongest suits of both designs in the opinion of the ADC pilots), the Northrop XF-89 Scorpion came out overall ahead in the evaluation and it was selected for production as having the best development potential. 

It was a crushing blow for Curtiss-Wright as the XF-87 was its only postwar jet design to take to the air. The Navy had canceled the XF15C mixed-propulsion fighter a few years earlier after only three examples were built. The company, in effect, was betting its future as an aircraft manufacturer on the XF-87 Blackhawk. The first prototype was  ferried to Wright-Patterson AFB in Ohio in December 1948 and was eventually scrapped by 1950. The second unfinished prototype was never completed and what was done got parted out for other projects that the company was attempting. With no other designs in advanced development, Curtiss-Wright was forced to shut down its Airplane Division and its assets were sold to North American Aircraft and the Columbus plant would be used for the manufacture of the F-86 Sabre. Curtiss-Wright's propeller division remained active into the 1960s and was responsible for the X-19 radial lift test aircraft. Some feel the X-19 was Curtiss' last aircraft design, but in reality it was the XF-87 Blackhawk that represented the end of the line for Curtiss-Wright Aircraft, a company that just ten years earlier was one of the dominant aircraft manufacturers of the United States. 

Related Reading:

The Massive Curtiss XP-71 Fighter
The Barrier Patrols: Extending the US Radar Net Out to Sea

Source: Experimental & Prototype U.S.Air Force Jet Fightersby Dennis R. Jenkins and Tony R. Landis. Specialty Press, 2008, p95-101. 

General Giulio Douhet, the First Air Power Visionary

Giulio Douhet, air power visionary
(Wikipedia)

Those of us interested in aviation take it almost for granted the unyielding pace of technological development that has driven aviation forward through time. But even less heralded are those in aviation history who have shaped the thinking of aviation- it's easy for us to lay eyes on an aircraft or even to put our hands on one. They're very tactile and sensory experiences in aviation- to see one, hear one, feel one, even ride an aircraft. But how do you experience aviation doctrine? How do you grasp the thought processes that have shaped aeronautical progress? They're very abstract and not prone to enjoyment and appreciation by most of us. However, technological progress is a rudderless boat in chaotic waters without visionaries and thinkers to provide steering and direction. Of course we can name designers like Jack Northrop or Andrei Tupolev. Or pilots like Charles Lindbergh or Chuck Yeager. But the subject of today's blog posting is none of those- he didn't design any aircraft, he didn't even fly aircraft. But his writings on air power have left an indelible mark on aviation, if not history itself. 

Born in 1869, Giulio Douhet was a rare breed of Italian army officer who was both an infantry and artillery officer and what we might call a technocrat, having studied science and engineering as well. His earliest writings as part of the General Staff of the Italian Army covered mechanization and the incorporation of what would be come tanks in military doctrine. But with the arrival of lighter-than-air aircraft like dirigibles and the first practical biplanes prior to the First World War, Douhet quickly appreciated the advantages of aviation in war- aircraft could move in three dimensions and operate above and out of the reach of ground and naval forces with relative impunity. In 1912 when the Italians first used aircraft in combat in Libya, he wrote Rules for the Use of Airplanes in War, one of the first efforts to create a doctrine for military aviation- despite his own background as an artillery and infantry officer, Douhet felt that the current military leadership lacked an understanding of the inherent advantages of air power and an almost zealous desire to educate the establishment on air power would be Douhet's mission in his life. 

When the First World War broke out in Europe in August of 1914, Douhet was forty-five years old and no less energetic than officers half his age. With a near-insatiable appetite for the latest developments in aviation, he advocated the building of a force of 500 bombers that could bomb enemy forces from above without having to engage in prolonged combat. He worked closely with the Italian engineer Gianni Caproni in advising him on his own Caproni line of bomber aircraft. But Douhet would find the Italian military leadership incompetent as defeat after defeat was suffered by Italian forces. Convinced that aviation technology could reverse the lagging fortunes of the Italian military, Douhet wrote and spoke frequently to anyone and everyone in the military and government establishment. By 1916 his superiors had had enough when he had ordered construction of Caproni bombers without authorization. He was stripped of his rank and imprisoned on charges of "issuing false news" and "disturbing the public tranquility". It didn't stop him, though. He continued to write and refine his theories from his cell. 

In the fall of 1917, the Italian Second Army was completely routed at the Battle of Caporetto (in modern day Slovenia), suffering over 300,000 casualties. The Italian government in desperation released Douhet from prison and commissioned him as a general in charge of coordinating the nation's aviation strategy and doctrine. It would be too little too late as the entrenched Italian bureaucracy was unwilling to enact his plans and he resigned in protest in June 1918. With the Armistice in November of that year ending the First World War, Douhet's trial verdict was reversed and he was promoted, but by this point in his life he had lost faith in the Italian government and refused to return to duty. During the interwar period he traveled Europe visiting other nation's air arms, consulting with air officers and meeting with aircraft designers. In 1921 he wrote his landmark work Command of the Air which advocated an relentless air campaign of bombing an enemy's population and production centers, reducing their moral and material means of resistance. Properly conducted, he reasoned, such an air assault could force a quick decision and save millions of lives in the long run by avoiding a costly ground war. Douhet also pointed out that the efficient and proper means of carrying out such an air campaign would require an independent air arm led by an aviation-minded general staff. At the time, this was a revolutionary concept and only in Great Britain was the nascent Royal Air Force an independent air arm. For other industrialized nations of the 1920s, their air arms were subordinated to the army. 

Billy Mitchell, USAAC
(Wikipedia)

Reception of Douhet's work outside of Italy was mixed. It wasn't even required reading at the RAF Staff College. But his work would find converts primarily in the United States- at the time the Air Force was part of the Army as the US Army Air Corps. One officer in particular would even meet with Douhet- Brigadier General Billy Mitchell. It was the year after Mitchell had demonstrated the vulnerability of warships to bombers by sinking several captured German warships off the Virginia coast. Mitchell had copies of Command of the Air sent to his superiors and he got banished to Hawaii and then Asia as a result. In 1925 Mitchell wrote a book of his own, Winged Defense, in which he refined Douhet's ideas of a strategic air campaign further and even declared the battleship obsolete as aviation technology matured. As a result, Mitchell was demoted in rank back to colonel. He would later be court-martialed for publicly criticizing the US military following the crash of the airship USS Shenendoah in a storm. But his six week court martial provided Mitchell the perfect forum for advocating views shaped by his mentor, Giulio Douhet. 

Sir Hugh Trenchard, RAF
(Wikipedia)

Douhet died of a heart attack in 1930 and Mitchell himself would die in 1936, neither man living to see how their views of air power would come to fruition in the Second World War. While Command of the Air got little attention in the Royal Air Force, the most influential individual in the RAF at the time fortunately was a proponent of Douhet's theories- Sir Hugh Trenchard, Chief of Staff of the RAF and the man known as the "Father of the RAF". Trenchard, like Mitchell, would refine Douhet's ideas. By the time of the Second World War, Trenchard was every bit the irritant to the establishment as Douhet and Mitchell were, but had enough influence to avoid their fate. Following the disastrous loss of Norway to the Germans in 1940, Trenchard used his position in the House of Lords to criticize Prime Minster Neville Chamberlain's prosecution of the war which contributed to his replacement by Winston Churchill. Trenchard used in influence to put like minded officers in key positions in the Royal Air Force. After the war, Trenchard advised General Henry "Hap" Arnold in his own push for an independent United States Air Force.

The same year Mitchell died in 1936, contracts were issued to both Boeing and Douglas for a large four-engined bomber- while both companies' designs, the XB-15 and the XB-19, respectively, remained experimental, the engineering and design work on such a unprecedentedly large bomber would shape aviation technology throughout the Second World War. 

Source:  Whirlwind: The Air War Against Japan, 1942-1945 by Barrett Tillman. Simon and Schuster, 2010, p9-16.

The Ultimate Superfortress: The B/RB-54A

Concept art of the B/RB-54A in flight
(Boeing Historical Archives)

During the Second World War Boeing worked extensively on further improvements to the B-29 Superfortress. The most important of these improved variants was the B-29D that involved swapping out the Wright R-3350 radial engines with the more powerful Pratt & Whitney R-4360 Wasp Major radial engine. In July 1945 the USAAF signed a contract for 200 B-29Ds, but with the end of the war and the rapid postwar demobilization, the B-29D contract was canceled. With the creation of an independent United States Air Force in 1947, there was a need for interim bombers pending the arrival of more advanced jet bombers. The USAF was already getting the Convair B-36 which took on the mantle of the heavy bomber, but the USAF also wanted the B-29D which would be redesignated as a medium bomber. The USAF had the B-29D redesignated as the B-50 to avoid the appearance of ordering a "wartime" bomber. Making its maiden flight on 25 June 1947, the B-50 Superfortress would eventually result in 320 examples of all variants produced.

Boeing, however, was working on an even more powerful and longer-ranged development of the B-50. Designated the B-50C, this evolution into the ultimate Superfortress was designed to extract as much speed and performance as was possible using a new version of the Pratt & Whitney R-4360 Wasp Major engine that added what was called a "variable discharge turbine" (VDT) to the engine. The standard Wasp Major used on the B-50 developed approximately 3,500 horsepower and a Wasp Major with a VDT could easily produce 4,000 horsepower, making it one of the most powerful production piston engines in the world.

The Wasp Major VDT
(from the Engine History website)

The VDT consisted of two General Electric CHM-2 turbosuperchargers that collected the hot exhaust gases from the 28 cylinders of the Wasp Major. A portion of the hot gases were diverted through an intercooler to provide turbosupercharging at high altitudes. The bulk of the hot gases went through the CHM-2 turbines and were exhausted out a variable area nozzle that resembled a set of eyelids. By adjusting the size of the nozzle, jet thrust could be achieved that had the potential to add as much as 15% to the speed of the B-50C over the production standard B-50. The Wasp Major VDT was already flying at this point on the Republic XF-12/XR-12 Rainbow long range reconnaissance aircraft. 

The scope of the changes needed to for the B/RB-54 resulted in a redesignation to B-54 with the planned reconnaissance variant being the RB-54. The jump in power output from the use of the Wasp Major VDT resulted in a redesign of the wings that resulted in a wingspan that was over 20 feet longer than that of the B-50 with a chord increase as well- an additional six feet of chord at the wing root and an additional four feet of chord at the wing tip. This provided additional fuel capacity along with external fuel tanks which were three times the capacity of the external tanks used on the B-50A on the outboard wings. The wingspan increase was so much that outrigger gears were needed under the outermost engine nacelles. Wind tunnel testing had shown that the new wing and powerful engine output also required a longer fuselage and the B/RB-54's fuselage was stretched 10 feet. Instead of the plexiglass domes used by the gunners on the B-29/B-50, low drag hemispheric sights were used. These used a fish eye hemispheric optical element that the gunner sighted through. Glenn's Computer Museum has some great pictures of the R/RB-54 hemispheric gunsight. The tail gunner also had a hemispheric gunsight but also had a radar to direct the four-gun turret as well which was mounted in fairing above the gun turret but below the hemispheric gunsight. Fairings were also present on the nose and under the forward fuselage for bombing and navigation radars. 

As a comparison, the B-29 weighed 120,000 lbs fully loaded and the B/RB-54 would weighed in at 207,000 lbs at takeoff. The Wright R-3350 engines of the B-29 developed 2,200 horsepower and the bomber had a range of approximately 3,250 miles. The B/RB-54 would have been able to push 8,000 miles of range. The mockups were completed in 1948 and the contract was signed for 43 bombers as an initial production lot. While the Secretary of the Air Force Stuart Symington and the USAF Chief of Staff General Hoyt Vandenberg were supportive of the B/RB-54 project, General Curtis LeMay, the head of the Strategic Air Command, felt that the B/RB-54 was inferior to the Convair B-36 Peacemaker particularly the B-36D that added four J47 jet engines under the outer wings. Pending the arrival of the B-52 Stratofortress, LeMay felt deterrence was better served by the B-36 which could fly faster, farther, higher, and carry a significantly larger bomb load. In the postwar atmosphere of austerity, more B-36s couldn't be accommodated in the Air Force budget and Secretary Symington offered LeMay more B-50s instead of increased numbers of B-36s. This was even more unsatisfactory to the outspoken SAC commander who then argued that if he couldn't get more B-36s, then the funding set aside for the B/RB-54 should be shifted over to get more of the Boeing B-47 Stratojet which made its first flight in December 1947. This was agreeable to all involved, even for Boeing as it meant more funding for the Stratojet program. The B/RB-54 project was cancelled with the prototype approximately 75% complete (it was converted from a B-50A) at Boeing's Seattle facilities. In addition, the addition of the outrigger gears wasn't popular with SAC as many of its bases would need widened taxiways and runways to accommodate the B/RB-54. 

The B-29 lineage would live on, though, in the C/KC-97 Stratofreighter (the last examples being retired in 1978) and in the commercial Boeing 377 Stratocruiser. But neither would have matched the leap in performance of the B/RB-54, the "ultimate" Superfortress.

The Retromechanix page has a series of superb photos via the National Archives that show the B/RB-54A mockup in detail as well as some schematic drawings. It's well worth the time to browse them!

Source: Boeing B-29 Superfortress (Crowood Aviation Series) by Steve Pace. The Crowood Press Ltd, 2003, p166-168. Boeing B-50 (Air Force Legends Number 215 by Geoffrey Hays. Ginter Books, 2012, pp 118-121.

The Boeing YB-40 Bomber Escort and Its Tall Tales

Boeing YB-40 in flight. Note the second dorsal turret.

It quickly became apparent with the start of daylight strategic bomber missions over Europe that fighter escort was desperately needed to get the heavy bombers to their targets and back. During the design phase of the Boeing B-17 Flying Fortress, air doctrine of the day called for the mutually supporting defensive fire from the bomber formation to be sufficient defense against enemy fighters. Early B-17 missions were against targets in northern France which were well within the range of Royal Air Force Spitfires which could provide escort cover- but as the Eighth Air Force began to dispatch its growing B-17 force against further targets, the Spitfires lacked the range. The Republic P-47 Thunderbolt and North American P-51 Mustang had yet to reach sufficient numbers in Europe to provide long-range escort and the only fighter in theater with the range, the P-38 Lightning, was desperately needed in the North Africa campaign. In those early days of unescorted daylight missions, only a quarter of combat losses were coming from anti-aircraft flak- the majority of bomber losses came from Luftwaffe fighters. The only aircraft with the range to escort the B-17s was quite obviously (at least to planners then) another B-17, so why not swap out a bomb-load for increased defensive armament as a large bomber escort? The passage of time has us not knowing who came up with the idea of a heavily armed B-17 as an escort, but in November 1942 the first XB-40 was ordered- taking a stock B-17F Flying Fortress from the license production line at Lockheed Vega (both Lockheed and Douglas were building Flying Fortresses to augment Boeing's own production), the XB-40 was modified with a chin turret with twin fifty-caliber guns to defeat head-on attacks by Luftwaffe fighters. In addition, the waist positions were staggered so the waist gunners had more freedom of movement and each gunner got a twin fifty-caliber on a flexible mount instead of a single fifty-caliber gun which was standard. Finally, a second dorsal turret was added where the radio room was located, this turret also had twin fifty-caliber machine guns. Space in the bomb bay was devoted to additional ammunition storage and fuel. Compared to a standard B-17F, the XB-40 had three times the ammunition for its beefed up gun armament. 

Interior layout of the YB-40 showing the increased guns.

A further twenty-four B-17Fs were taken from Lockheed Vega's production and delivered to the Douglas B-17 plant in Tulsa for modification to YB-40 standard (the "Y" prefix indicating a service test aircraft as opposed to an experimental prototype which would use the "X" prefix). There were only minor differences between the first XB-40 and the YB-40 series of aircraft. Some sources suggest different armament combinations were trailed including cannons, but the aircraft were sent to Europe standardized on the Browning fifty-caliber machine gun for all the defensive positions. The 92nd Bomb Group at RAF Alconbury would be the first unit to take the YB-40 into combat to prove the concept. Of that group of twenty five aircraft (including the XB-40), thirteen would be sent to Europe- one was lost on the ferry flight, making a forced landing in a Scottish bog, leaving twelve to continue on to Alconbury. The first mission was flown on 29 May 1943 with seven YB-40s accompanying a B-17 force to hit the Kriegsmarine U-boat pens at Saint-Nazaire, France. The YB-40s, loaded with extra guns and ammunition, were slower than regular B-17Fs and handling at altitude was sluggish. The entire formation had to slow down to allow the YB-40s to keep up. On the return leg, the now empty B-17Fs could fly higher and faster no longer burdened with their bomb-loads, but the YB-40s still had their guns as they didn't exactly lighten over the course of the mission as they didn't have a heavy bomb-load to drop. Marauding German fighters focused on stragglers in the bomber formations and while the YB-40s had the defensive fire to fend off the attacks,  no one was thrilled about the prospect of being the formation straggler on every mission. The Eighth Air Force command was less than impressed- the last mission was flown on 29 July 1943 with only two months of operating experience- nine missions were flown with the loss of one aircraft. Five German fighters were confirmed as shot down by the YB-40s with two probable kills. It was hardly a resounding performance and the YB-40 program quietly wound down. Through 1943 until early 1944, the YB-40s returned to the United States. Twelve aircraft of the original twenty four never left the United States and were ultimately scrapped. 

Layout of the YB-40's additional gun armament.

The experience of the YB-40, though, did leave a legacy with the B-17 force. The next variant of the B-17 to follow the B-17F, the B-17G, featured the chin turret and the staggered waist gun positions that were used on the YB-40s. Some sources indicate that the improved "Cheyenne tail turret" (so named from the United Air Lines modification center in Cheyenne, Wyoming) was also an outgrowth of the YB-40 program. 

Two tall tales have sprung up from the YB-40 story that are often repeated on websites, publications and even books. Both of them are just that- fanciful stories and we'll discuss both of them for the record and why they're tall tales and not true historical events. 

The first story concerns a B-17 pilot with the Twelfth Air Force in the Mediterranean named Harold Fischer (in some stories spelled Fisher). Returning to their base in North Africa after a mission against the Italian island of Pantellaria, Fischer's B-17 lagged behind the formation as it had two of its engines shot out. A lone P-38 Lightning formed up on his bomber and offered to escort them. It soon took up position behind the crippled B-17 and shot it down over the sea with Fischer as the only survivor. His story was met with disbelief until USAAF intelligence officers corroborated his story that a P-38 that had gotten lost had fallen into the hands of the Italians and it was being flown by a Regia Aeronautica ace, Guido Rossi, to shoot down B-17 stragglers. Fischer was the first B-17 crewman to have survived Rossi's ruse as he had already downed nine bombers with the captured P-38. Fischer came up with a plan to exact revenge on Guido Rossi and a YB-40 was requested from the Eighth Air Force in August 1943 which Fischer would fly, playing the part of a B-17 straggler to trap Rossi. After two weeks of flying, they hadn't gotten Rossi but the Italian added more kills to his P-38. Determined to get him, Fischer worked with Allied intelligence to find out as much as he could about Guido Rossi and learned his wife and child were living in an Italian city that was in Allied hands. Fischer went to the home of Gina Rossi to meet her and had an artist paint a portrait of her on the side of the YB-40 which he aptly named "Gina". 

On the next mission to Pisa, Italy, Fischer's YB-40 took heavy damage and ended up getting met by Rossi's P-38. Noting the nose art, Rossi asked Fischer if the woman on the nose of the plane was from his own town. Realizing they had Rossi, Fischer confirmed Rossi's suspicions and began to sing the praises of Gina's lovemaking abilities. Filled with rage, Rossi attacked the YB-40 and a running gun duel ensued with Rossi at one point trying to ram the bomber. Rossi was eventually shot down over the sea and survived. As the story goes, Fischer got the Distinguished Flying Cross for it and the two flyers eventually met after the war, but Fischer was killed in a crash during the Berlin Airlift.

Sounds like a great story, but there was no Italian ace named Guido Rossi. A P-38 did fall into Italian hands during the war and its pilot was known and the aircraft as only flown in an evaluation role. There is no record of the YB-40 operating in the Mediterranean theater of operations- while there were two bomb groups with B-17s assigned to the Twelfth Air Force, neither of them operated the YB-40 either. And most damning to the veracity of this story, there is a pilot named Harold Fischer who got the DFC- but he was USAF F-86 Sabre pilot in the Korean War- he was the 25th ace of the war and was imprisoned by the Chinese after getting shot down and wasn't released until 1955. 

The second tale relates to one 1st Lt. Harry Reid with the 95th Bomb Group of the Eighth Air Force who with one of his lead pilots, had noted a lone B-17 that would tail their bomber formations on their missions over Europe. In June 1944 as the story goes, Reid and his lead pilot, Captain Glenn Infield, hatched a plan on their own initiative to use a parked YB-40 at their base to get this lone B-17 which they suspected was a captured Flying Fortress being flown by the Luftwaffe to tail formations and give position, altitude and heading information on the formations to defending Luftwaffe fighters. On a mission against a target in Brussels, Reid and Infield set their plan in motion. Sighting the lone B-17, they closed on it. The aircraft then veered away from them, confirming their suspicions as a one B-17 would have formed up with any other B-17 right away for mutual defensive fire from the gunners. Pursuing the German-flown Flying Fortress, the YB-40 was bounced by six Focke Wulf Fw 190 fighters. Reid and Infield astutely realized if they stayed close to the captured B-17, it made the Fw 190's task harder out of fear of hitting the wrong B-17. Their radio operator happened to speak fluent German and he got on the Luftwaffe's fighter frequency and directed the Fw 190 pilots to attack the captured B-17 while they made a sharp break to the right. Thinking they had gotten direction from their own B-17, the Fw 190 pilots made their attack before their own B-17 could protest! With the captured B-17 damaged, the YB-40 completed a full turn to the right and came up and behind the other Flying Fortress, finishing it off just as escort fighters arrived on the scene. Because their plan was hatched of their own initiative without the approval of their superiors, Reid and Infield were never formally decorated for their actions. 

Again, sounds like a great story, but the last YB-40s were documented to have returned to the United States by March 1944. Most of the original twelve that flew missions had returned through 1943 but three were left in Great Britain at the start of 1944. One returned to the United States in January 1944 and the last two returned in March 1944, making the timeline of this second tale impossible. In addition, while the 95th Bomb Group was co-located with the 92nd Bomb Group at RAF Alconbury, there is no documentation of the 95th BG having flown the YB-40. Only the 91st, 92nd, and 303d BGs ever flew the YB-40. 

Sources: Aerial Gunners: The Unknown Aces of World War II by Charles Watry and Duane Hall. California Aero Press, 1986, p167-174. "Brilliant Mistakes: The YB-40" by Robert Dorr. Defense Media Network at http://www.defensemedianetwork.com/stories/my-brilliant-mistake-the-yb-40/. Photos: USAF Museum, 92nd Air Refueling Wing Historians, Squadron Publications via War Thunder Forums.

The USAAF Looks for Something Better than a C-47

Loading a Jeep into this RAAF C-47 shows it wasn't ideal for large or bulky loads.

During the interwar period of the 1920s, US military air transport was modest at best and consisted primarily of "off the shelf" civilian designs that were modestly modified with things like reinforced cabin floors and wider doors but were essentially airliners without seats. Until 1934, for example, the US Navy and Marine Corps relied on Ford Trimotors for transport! The arrival of the Douglas DC-2 offered a big improvement in capability for the US military. With war clouds looming in Europe and Asia in the 1930s, the US Army Air Corps went about looking for something better than adapted DC-2s. Bids were requested and Douglas offered an attractive proposal for upgraded DC-2 aircraft better tailored to military transport operations. Not long after, General Henry "Hap" Arnold became head of the USAAC (which later became the USAAF) and being a personal friend of Donald Douglas, was well aware of a DC-2 upgrade in the works that was the result of a marathon telephone conversation between Donald Douglas and the head of American Airlines, C.R. Smith. That aircraft was a leap in performance and capability over the DC-2 and at the time was called the Douglas Sleeper Transport (DST). In due time, of course, the DST became the DC-3 but General Arnold saw the DST's design and performance as an ideal basis for a transport. Army officials met with the designer of the DST, Arthur Raymond, and the C-47 was born. When the war finally broke out with the German invasion of Poland in September 1939, the C-47 wasn't yet in production and suddenly the branches of the US military needed air transport aircraft. The C-47 Skytrain (Dakota in RAF service) made its first flight on 23 December 1941 as Douglas embarked on a major facility expansion to meet the demand for the C-47. At production peak in May 1944, the company was building just under 19 C-47 aircraft each day! Despite the massive expansion and number of C-47s needed, the Army did have several issues with the C-47 but it was the best aircraft available at the time. There were three main issues the Army had- the first was that the tailwheel configuration and side cargo door made it difficult to load large items. Secondly, the maximum payload was too light as it was based on the maximum civilian load for the DC-3, and thirdly, the Army felt that as it was a DC-1/DC-2 derivative, it was old technology. With the United States now in the war, the Army thought that aluminum production was best used for armed combat aircraft and that cargo aircraft which operated in support roles ought to use non-strategic materials. While there was never a formal competition for a C-47 replacement but rather a series of issued requirements, quite a bit of money was spent over the course of the war to develop a transport that was better than the C-47. 

Budd C-93/RB-1 Conestoga

At the outbreak of war, several aircraft made out of the non-strategic materials made the first attempt at replacing the C-47. The first came from the E.G. Budd Company of Philadelphia- they had developed the shotweld technique for joining two pieces of metal- it used a short burst of electrical current to bond two pieces of metal. Invented in 1932 by a Budd engineer, shotwelding was used on the products Budd was known for- railroad cars and road vehicle bodies made of stainless steel. In discussions with the US Navy, Budd hired an aeronautical engineering staff to design a shotwelded (therefore no rivets) transport that would be made of readily available stainless steel. The Navy ordered 300 to be designated the RB-1 and the Army ordered 600 to be designated the C-93. Though made primarily of thin-gauge stainless steel, the wing aft of the spar and the moving surfaces of the tail were fabric covered to offset the weight of the steel. 

The design of the Conestoga was radical for the day and set the pattern for an efficient military transport even to this day. A high mounted wing allowed for an unobstructed main deck with a tricycle landing gear to keep the main deck level and low to the ground to ease loading. An aft loading ramp/door allowed rolling stock to be driven on/off of the aircraft. The flight deck sat up above the main cargo deck to maximize the cargo volume of the fuselage. In addition, there was an integrated hoist in the cargo deck to ease loading an locations that lacked ground equipment. The first flight was on 31 October 1943 and three prototypes conducted the flight test program. Using the same engines as the C-47, the Conestoga was underpowered and possessed sluggish handling- pilots joked that for a plane made by a railroad car company, it sure handled like one! By time time cost overruns and construction delays were resolved at the Budd factory, aluminum production had vastly increased in the United States and the need for an aircraft made of non-strategic materials diminished. The Army canceled its order for the C-93 and the Navy reduced its order from 300 to just 25. Just 17 RB-1s were delivered to the Navy by March 1944 and that small number served primarily as hacks for naval air stations. With such a small number in the fleet, the Navy found the RB-1s uneconomical and sold them off as surplus in early 1945 before the war even ended. Twelve Conestogas were purchased by a new cargo operation, National Skyways, that was founded by a group of pilots that had once served with the American Volunteer Group in China. National Skyways would later change their name to Flying Tigers- but that's a story for future blog article!

Curtiss C-76 Caravan

Another aircraft from the Army's concerns in 1941 that was a contemporary of the Budd C-93/RB-1 Conestoga was the Curtiss C-76 Caravan. The company was engaged by the Army that year to build a transport aircraft that like the Conestoga, would not only be made out of non-strategic materials but also exceed the performance and utility of the C-47. The Caravan was designed by the chief designer at Curtiss, George Page, who was also responsible for the C-46 Commando. While the Conestoga would be made of stainless steel, Page elected to use wood for the Caravan but interestingly, the only high performance aircraft at the time in production made from wood, the De Havilland Mosquito, wasn't used as a source of expertise. De Havilland used a layered plywood construction using a lightweight balsa wood core that made the Mosquito strong but light. Curtiss engineers instead favored mahogany in layers- being a much denser wood than what was used on the Mosquito, the Caravan soared in weight. Despite this, the Army helped Curtiss secure large stocks of mahogany and a number of furniture manufacturers were set up as component subcontractors with final assembly at Curtiss's new plant in Louisville, Kentucky. 

Much like the layout of the Conestoga, the C-76 Caravan featured a retractable tricycle landing gear to keep the main deck level. It also had a high wing layout for an unobstructed main deck hold and also put the flight deck above the main deck. Instead of an aft loading door and ramp, the Caravan had a swing nose that opened to the side ahead of the flight deck. The prototypes were built at existing Curtiss facilities in St. Louis as well as the new Louisville plant with the first flight on 3 May 1943. The flight test program was a disaster. The aircraft, using the same engines as the C-47 but made of dense mahogany, was woefully underpowered with a cargo payload not much more than the C-47. On the first flight, the aircraft vibrated so badly the flight test crew made a hasty return to the St. Louis Lambert Field. On the second test flight, the prototype literally shook itself apart with the loss of the pilots. In addition, when empty, the Caravan had to be ballasted to maintain its center of gravity- amusingly, the ballast needed to maintain an empty load CoG was more than the maximum payload! The control surfaces suffered from buffet and even shook while the plane was on the ground if it was windy. The wing spar failed load testing eight times, only holding up to 40% of the predicted maximum load. The Army wasn't pleased and was more than happy to cancel their order for 175 C-76s, particularly as aluminum production had vastly increased as the war progressed. Only 14 aircraft were built and most spent their days as ground instructional airframes. 

Wind tunnel model of the Waco C-62

There was a third aircraft that stemmed from the Army's 1941 call for something better than the C-47, but it never flew. Waco Aircraft had been building both training and assault gliders for the military and they tendered a design that received the designation C-62. Like the Curtiss C-76 Caravan, the Waco design was made out of wood and featured a high wing and rear loading door/ramp. The tadpole-shaped aircraft had the empennage cantilevered over the aft ramp on a boom. The undercarriage was fixed as well. Using the same engines as the C-47, the Army placed orders for 13 pre-production examples and 240 production aircraft. However, again, like the Conestoga and Caravan, the anticipated shortage of aluminum never occurred and the C-62 was canceled. Allegedly the first aircraft was nearing completion at the time of the cancellation, but this hasn't been confirmed. 

Fairchild C-82 Packet at the National Museum of the USAF

The last aircraft that sprang from the 1941 call was the Fairchild C-82 Packet. Designed by Fairchild's chief designer, Armand J. Thieboldt, the original plans were for the C-82 to be made of wood. Like the other three aircraft, the Packet had a high wing and tricycle landing gear to allow for a level main cargo deck that was unobstructed. The flight deck was raised above the cargo deck and a twin boom layout was chosen to leave the tail area completely clear for straight though loading and unloading. With the fortunes of war shifting in favor of the Allies in the summer of 1942 after the Battle of Midway and an expansion of domestic aluminum production eased shortage concerns, the USAAF requested that Fairchild abandon wood for the C-82 and go with aluminum. Of four aircraft designs for a C-47 replacement, the decision to switch to aluminum more than likely contributed to the reasons why the Packet did get to production and service. Being the last submission probably saved the design as it was also redesigned to take a more powerful engine, the Pratt & Whitney R-2800 Double Wasp instead of using the same engines as the C-47. As a result, the C-82 had the highest cargo payload of the four designs. 

First flight took place on 10 September 1944 at Fairchild's plant in Hagerstown, Maryland. The first series of flights were so encouraging that the USAAF ordered 100 C-82s just 18 days after the first flight. With an eye towards the coming invasion of Japan, North American's Dallas plant was planned for an additional 1000 C-82s on top of an additional 100 from Fairchild for a total of 200 from the Hagerstown plant. The first C-82s were delivered to the USAAF in June 1945 but the sudden end of the war with the Japanese surrender in September 1945 resulted in the cancelation of the North American production run at Dallas with only just three Dallas-built C-82s being built. Despite the drawdown in US military forces, the C-82 Packet was the C-47 replacement the USAAF wanted and the 200-aircraft order from the Fairchild plant in Maryland stood to fulfill postwar airlift requirements. Five C-82s participated in the Berlin Airlift, bringing in heavy equipment and vehicles that couldn't be accommodated onto the Douglas C-54 Skymasters. Operational use of the C-82 revealed several shortcomings, the most concerning of which was that with a full load, a C-82 with one engine out couldn't maintain level flight. Thieboldt and his team at Fairchild went about improving the C-82 design first by incorporating more powerful engines in the form of the Pratt & Whitney R-4360 Wasp Major as well as a host of other improvements to satisfy the newly-independent US Air Force's concerns. Originally designated XC-82B, the changes were so significant that a new designation was assigned to the upgrade which became the C-119 Flying Boxcar. The first flight was made on 17 December 1947. As C-119s were delivered to USAF units, the C-82s were retired. A total of 220 Packets were built. Quite a few Packets had long civilian careers, but that's a story for future blog article! 

Source: The Legacy of the DC-3 by Henry M. Holden. Wind Canyon Publishing, 1996, pp 141-148. Information also from National Museum of the USAF, Wikipedia and www.c82packet.com. Photos: Wikipedia, Australian War Memorial, National Museum of the USAF. C-62 wind tunnel model from R/C Groups forum.

The Unconventional Genius of Carl Norden

Carl L. Norden

After the Manhattan Project to develop the atomic bomb, the next biggest top secret defense program in the United States at the time was the development and production of the Norden bombsight. The Norden sights were used in all of the United States Army Air Forces heavy bombers (the Boeing B-17 Flying Fortress, the Consolidated B-24 Liberator, and the Boeing B-29 Superfortress) primarily and it was a Norden sight that bombardiers used to drop the atomic bombs on Hiroshima and Nagasaki that brought the Second World War to a close. Despite its crucial role in strategic bombing campaigns in both the European and Pacific Theatres, the Norden bombsight was a Navy program and every Norden sight used by the US Army Air Force had passed through the hands of Navy inspectors. How this state of affairs came to be is the story of how an unconventional but brilliant Dutchman, Carl Norden, came to be employed by the Navy prior to the start of the Second World War. 

Carl Norden was born on 23 April 1880 in Semarang, Java, in what was the Dutch East Indies (modern day Indonesia), the middle child of five siblings in a household with absent father. From a young age, his mother considered him the most reliable and responsible of his siblings- in a sense, he became the "man of the family". He had wanted to become an artist, but when his older brother decided to pursue an artistic career, Carl decided to pursue a lucrative career in order provide for his mother and his siblings, enrolling in the Federal Polytechnic Institute in Zurich, Switzerland and graduating in 1904 as a mechanical engineer. Although Dutch by birth, Norden's father was a naturalized Dutch citizen from German and Norden's own wife was from Austria. Norden's German ties dovetailed into his natural engineering and mathematical prowess- it was said that Carl Norden viewed everything in life in mechanical terms governed by mathematical formulas, the universe being nothing more than a great mechanical timepiece. After his graduation in 1904, he emigrated to the United States where he had a wealthy uncle who had made his fortune in the cotton business. Norden worked for a series of companies as a mechanical design engineer, but it was painfully obvious that he was difficult to employ as he was very much a prima donna. But there was no question of Norden's brilliant mind and after a series of employers over six years, he finally came to work for Elmer Sperry Sr. and his sons, Elmer and Lawrence at the Sperry Gyroscope Company. Norden's mechanical aptitude fit well into the work the Sperrys were doing for the Navy in developing gyroscopes to improve the accuracy of naval gunnery from moving ships. Norden's work with Sperry was invaluable for the company and Norden made many contacts within the Navy as a result. Norden tolerated Sperry as the work was interesting, but the relationship soured when, after solving the problem of gyroscopic oscillation, Norden got what he thought was an insulting $25/week raise as a reward. Norden quit and became a consulting engineer to the Navy, but it was the start of a feud between Norden and Sperry for years. Norden often dismissively told people Sperry "would patent gravity if he could" and Sperry for years tried to legally dispute many of Norden's later patents. 

In 1913, Norden set up shop near the Brooklyn Navy Yard and continued to work on the ship stabilization project for the Navy much to Sperry's chagrin. The Navy was enamored with Norden's genius and that relationship in large part protected Norden from Sperry's multiple legal challenges. With the progress on the ship stabilization project slow in coming, the Navy astutely put Norden's mind to work on other projects, starting the aerial gyroscopes for the aerial torpedo project as well as designing catapults and arresting gear for aircraft carriers. The arresting gear of the USS Lexington and USS Saratoga were designed by Norden himself on his dining room table!

At the time, the Navy was pursing a bombsight program as it felt that the best way to sink ships from the air was via high altitude level bombing. General Billy Mitchell's ship-bombing tests in the summer of 1921 against captured German warships convinced the Navy that it had to find a way to sink ships at sea. The Navy's Bureau of Ordinance (BuOrd) was responsible for the bombsight program and many different types, including some from Sperry, were tested. Officers with the Aviation Section of BuOrd came to know Carl Norden from his work on the aerial torpedo project as he had been consulted as an outside expert to evaluate Sperry's work (something which truly irritated Sperry to no end). They were impressed with the comments made in the reports and not knowing who Carl Norden was, found a report signed "Norden". A quick check of the Brooklyn telephone book and a few calls got the officers from BuOrd in touch with Norden who agreed to review the Navy's bombsight program. The gyroscopic stabilization work he had done for the ship and aerial torpedo project dovetailed neatly into the bombsight problem as Norden recommended that the bombsights be not only gyroscopically stabilized, but also connected to either an autopilot or pilot director so that during the bomb run, the bombardier was the one "flying" the aircraft. Eventually modifying existing bombsights turned out to be a failure and the BuOrd and Norden decided to start from scratch and create a whole new bombsight that would launch the Norden bombsight into aviation history. 

That's not to say that Norden's genius resulted in success. For most of the 1920s, many of the literally handcrafted Norden sights had dismal performance. But Norden wasn't one to give up and the Navy was an incredibly accommodating employer. Well aware of Norden's personality- they nicknamed him "Old Man Dynamite", they gave him tremendous latitude as long as he kept delivering results in the form of progressive improvements to his bombsight designs. Unlike most engineers, Norden did his own drafting. He didn't have an extensive engineering library, he preferred to work with his slide rule, a set of engineering tables and a few select references. He often stayed at his mother's home in Zurich, Switzerland, to ponder mechanical problems and develop solutions. His drawings and correspondence were then delivered to the US Navy by diplomatic pouch from US embassy in Switzerland. The State Department wasn't keen on this but high level pressure from the US Navy encouraged diplomatic officials to be as accommodating to "Old Man Dynamite" as possible. Sometimes it was his family he sent to Switzerland so he could be alone to solve some problems back in New York. Also unique to the Navy's relationship with Norden was that any patents were held by the Navy and classified as top secret. In this way, not only was Norden shielded from Sperry's legal challenges, but it also meant that the Navy didn't have to follow the prescribed competitive bidding rules to pay Norden for his work. Many of Norden's patents sponsored by the Navy from the 1920s and 1930s weren't even declassified until 1947! In contrast to the US Army Air Corps (forerunner of the US Army Air Forces) who held open competitive bidding in its own bombsight program and trialled bombsights from several different manufacturers, the Navy only did business with Norden and Norden alone. In fact, the Navy was Norden's only client! 

Theodore Barth at a circus held for Norden employees

As work on the Norden sights continued in the 1920s, BuOrd recommended that Norden partner up with an engineer to start moving the bombsight project towards mass production. Knowing Norden well, the Navy partnered him up with a former Army colonel and engineer by the name of Theodore Barth and it was the start of a very close relationship between the two men for many years. Norden's own children regarded Barth as a secondary father figure in their lives, so close was Barth to Norden. It was Barth who was tasked by the Navy to take Norden's designs and put them into production. Compared to Norden, Barth was very personable and possessed quite a bit of business acumen as well- Norden may have been the brains of the operation but it was Barth who made everything work and kept everyone happy. During the Second World War, Barth took it as his job to take care of all of the employees that were building bombsights. He often gave away baseball tickets and even rented out Madison Square Garden for a circus just for Norden's employees. 

From the time Norden was contacted by the Aviation Section of the Bureau of Ordinance to the delivery of the first production bombsight to the fleet, the Norden Mark XI, nine years had elapsed. During those nine years Norden progressively refined the design of what was essentially a clocklike analog computer that was gyroscopically stabilized and linked to the autopilot. The Navy, though, did hedge its bets just a bit- during that time it had contracted with General Electric for a back up bombsight design called "Scheme B" or the Mark XIII. After three years, the Navy found the GE bombsight was woefully inferior to Norden's designs and canceled "Scheme B". 

Norden M-1 bombsight

By the early 1930s, the US Army Air Corps became aware of the Norden program and was keen to get its hands on the bombsights for its own testing. The head of the Army Air Corps, General Henry "Hap" Arnold (who would head the USAAF during the Second World War), was shocked to hear of the working arrangement between the Navy's BuOrd and Carl Norden, from Norden not even being a US citizen to the fact that Norden did a lot of his work abroad in Switzerland and then sent drawings back via diplomatic couriers to New York City for Theodore Barth and Navy officials to review. The Navy wasn't about to change the way it did business with Carl Norden to assuage General Arnold's concerns, though. It basically came down to something along the lines "If you want Norden bombsights for Army bombers, this is the arrangement you have to live with!". As a modest concession, though, the Navy had the FBI provide a security detail for Norden and agents were planted in Norden's production facilities in New York City to root out any foreign spies. At all times, at least two armed agents were with Norden at all times. There is an apocryphal story that when Norden wasn't getting his way with the Navy, he'd insinuate he'd leave the United States and go to work for the British. He would later remark it was empty threat "As no self-respecting Dutchman would ever work for the British!"

By 1928, Norden was at work at a massive improvement to the Mark XI sight called the Mark XV. He delivered the Mark XV prototype to BuOrd in 1930 and it was this sight that pretty much ended the GE alternate bombsight program. The bombsights that came from the Mark XV design were known as the Norden M-series sights and those would become standard on American heavy bombers.  By this point, however, the Navy was drifting away from relying on high altitude level bombing at sea as dive bombing was explored by units in the fleet. But the arrangements between the Navy and Carl Norden remained with his New York City factory essentially being a Navy factory! By 1934, Norden's bombsights became the standard for the Army Air Corps, first being installed on Martin B-10s. It's estimated that approximately $1.5 billion was spent on the development and production of Norden bombsights. 

Carl Norden was passed away in 1965 in his beloved Switzerland. His company lived on as Norden Systems to be acquired by Westinghouse which was in turn acquired by Northrop Grumman. Norden and Barth also set up a second company called Barden to manufacture bombsight components- Barden is still  around today, fabricating ball bearings for a variety of industries including aerospace. Carl Norden was inducted into the National Aviation Hall of Fame in 1994. 

Source: America's Pursuit of Precision Bombing, 1910-1945 by Stephen L. McFarland. Smithsonian Institution Press, 1995, pp 45-76. Photos: Norden Systems Division via Stephen L. McFarland's book, Wikipedia