Arthur Young Gets Bell into the Helicopter Business

Lawrence Bell, founder of Bell Aircraft
(Airport Journals.com)

In his book The Bell Helicopter Textron Story, David Brown says of Larry Bell, the founder of Bell Aircraft, "Larry Bell was different. With the visionary's eye, he saw his first helicopter and was impressed. When he saw his second (helicopter), he understood that here was an industry waiting to be born." Larry Bell was one of the early American aviation pioneers- after high school he worked as his older brother Grover's mechanic for several years while his brother conducted barnstorming flights. In 1913, his brother was fatally injured in a crash and Bell resolved to stay away from aviation. It wouldn't last, though. He first went to work for his brother's flight instructor, Glenn L. Martin, as a stockroom clerk in Martin's fledgling aviation company. He advanced quickly through the company and ultimately ended up as the Martin Aircraft vice-president and general manager. It was Bell who hired the first college-educated aeronautical engineer for the company- a young MIT graduate named Donald Douglas. It was Bell who got the Army interested in a heavy bomber called the Martin MB-2 that was one of Douglas' early projects. And it was Bell who convinced a brash Army aviator named Billy Mitchell to use the MB-2 to prove that bombers could sink battleships. In 1925, Bell asked to own stock in Martin but Glenn Martin rebuffed his offer of part ownership of the company. Bell resigned and within three years was hired by Rueben Fleet, the president of Consolidated Aircraft. Fleet allowed Bell to own a sizable portion of Consolidated shares and by 1929 he was promoted by Fleet to be the general manager of Consolidated. In 1935, Fleet wanted to move Consolidated from Buffalo, New York, to southern California to take advantage of the better flying weather. Bell didn't want to move, so he resigned but a group of investors backed him in purchasing Consolidated's facilities in Buffalo for the new Bell Aircraft Company. Interestingly, Bell was the third tenant of the factory- it was originally built in 1916 for Glenn Curtiss and at the time was considered the largest aircraft factory in the world. 

Bell's first aircraft was the YFM-1 Airacuda (Bell Model 1) which was a heavy bomber destroyer twin engined fighter. Only thirteen of the unique pusher twins were built and only a single squadron of Airacudas was activated as it was an aircraft ahead of its time. But the US Army Air Corps liked Bell's innovative thinking and asked him for a heavily-armed single engined fighter and this became the Bell Model 12, better known as the P-39 Airacobra which first flew in 1938. It was a remarkable start for Bell's fledgling company and in 1938, President Franklin D. Roosevelt asked Bell to join a group of American industrialists who had been invited tour Nazi Germany. Roosevelt wanted an expert opinion of Germany industrial capacity from the group and Bell was asked to join to assess the Nazi's aviation capabilities. Bell witnessed a flight demonstration of the Focke-Wulf Fw 61 helicopter flown by Hanna Reitsch and he considered the most impressive thing he'd seen on his tour of Germany. 

That was the first helicopter Larry Bell saw- to get to the second helicopter he saw in 1941, we have to step back a bit to look at the story of a unique inventor named Arthur Young. A native of Pennsylvania, while a student at Princeton University, Young was very interested in philosophy and tried to develop an original line of philosophical thought but was unsuccessful. He decided that he wouldn't be able to do so without some real-world experience solving problems. Graduating from Princeton in 1927 with a mathematics degree, Young searched for a technical challenge. He scoured city libraries in the East Coast and made regular visits to the US Patent Office in Washington in his search. He came across a book in his searches by German helicopter pioneer Anton Flettner who had invented a ship that used the Magnus effect from rotary drums to sail across the Atlantic. Flettner had described improving windmill efficiency by using small propellers at the tips. Young thought Flettner's concept could be applied to aircraft and of course that aircraft would be the helicopter, one of the unique flying machines of the day. He set himself on the task of developing a successful helicopter. 

Arthur Young and one of his late helicopter models
(State Archives of Florida, Steinmetz Collection)

Young set up an experimental workshop in a barn on his wealthy family's large estate in Pennsylvania. He refined his ideas using small models and his first design flew in 1931 using parts he obtained from a local toy shop- using rubber bands, hand-carved wooden blades with propellers at the tips and a balsa structure, his first model had a rotor diameter of six feet and it flew for only ten seconds. For the next nine years he worked at improving the Flettner concept, moving to the use of electric motors. He went through so many crashed models he literally learned how to mass produce his own helicopter blades. One of the problems Young encountered was getting his models into a stable hover. Over time he used his mathematics background to calculate stresses and build his own components based on his stress calculations. In doing so, he developed many of the concepts and tools used to measure rotor lift, propeller efficiency as well as equations to calculate a variety of power requirements for helicopters. 

In 1938, Young attended a conference of helicopter designers and learned of the pioneering work of Igor Sikorsky. Sikorsky himself gave a lecture on the use of a tail rotor to counter the torque of the main rotor. Young was fascinated by Sikorsky's lecture and set about to revise his model testbeds with tail rotors, disposing of the complex gearing that he had been working on to drive tip propellers. Stability in a hover continued to plague his efforts- he had tried a pendulum within the fuselage, but the pendulum arrangement he designed couldn't distinguish between the force of gravity and the force of acceleration. He then came up with the stabilizer bar- a bar with weights on the end that was perpendicular to the rotor. The weighted bar when spinning acted as a gyroscope that stabilized the helicopter in a hover. He used an electrical control system that ran to a box where he controlled the helicopter with extreme precision. He took his models on demonstrations to various aircraft companies where he showed how he could fly his helicopter models indoors and even in and out of doorways. He even gave a demonstration to the Army's aeronautical development center at Wright Field in Dayton, Ohio, but failed to find any financial backers. 

Dr. John Sharp was a physician who had seen one of Arthur Young's demonstrations. Sharp had a unique hobby in that he designed gearing systems in his free time and was working on a new gearing concept for a variable pitch propeller was pitching his ideas to Bell Aircraft. In 1941, Sharp was meeting with a Bell engineer named Jack Strickler and in casual conversation, Sharp spoke highly of Young's helicopter flight demonstrations. Strickler than passed on what Sharp told him to Larry Bell himself. Since Bell was impressed with what he had seen with the Focke-Wulf Fw 61 helicopter in his 1938 tour of Germany, he invited Arthur Young to come to Buffalo to give a demonstration of his helicopter design.

On 3 September 1941, Young arrived at Bell's Buffalo plant and was taken to a hangar where P-39s were prepared for delivery. Bell ordered the personnel in the hanger to stop work and move the P-39s outside to give Young room for his demonstration. Not only did Young fly a successful demonstration for Larry Bell, he also reviewed with Bell films showing his previous design efforts and showed him his notes on the design process he had developed to solve the problems of vertical flight. Bell was enthralled by Arthur Young and wanted to hear Young's ideas on a full-size piloted helicopter design. In a matter of weeks they reached an agreement where Young would come to Buffalo and work for Bell in developing a new helicopter based on his designs. Young assigned his patents to Bell Aircraft and Larry Bell funded the development of two full-sized helicopters. Young wanted two aircraft in case one crashed and Bell insisted that the second prototype be a two-seater so he could go on a ride! 

The rest, as they say, was history! That first helicopter, the Bell Model 30, will be the subject of a future article here at Tails Through Time. Stay tuned!

BONUS: A three part interview with Arthur Young in his later years about his design efforts

Sources: The Bell Helicopter Textron Story: Changing the Way the World Flies by David A. Brown. Aerofax Publications, 1995, pp 1-19. "Arthur Young: Maker of Bell, Part 1" by Robert Tipton, http://www.arthuryoung.com/maker1.html. 

The 24th Combat Mapping Squadron: Unsung Heroes of the Pacific War

Squadron emblem of the 24th Combat Mapping Squadron

While much has been written about the superiority of the Consolidated B-24 Liberator versus the Boeing B-17 Flying Fortress in the Pacific Theater during the Second World War (in short, it could carry more a longer range and at higher speeds than the B-17), there is one role that the B-24 played in the Pacific that still remains relatively unknown to most, that of combat mapping. The missions flown in particular by the 24th Combat Mapping Squadron in the China-Burma-India theater were of tremendous contribution to the overall war effort even though the crews of the 24th CMS fought their battles with rolls of film rather than bombs. 

On 2 September 1942, the 24th Combat Mapping Squadron was established as the 24th Photo Mapping Squadron at Petersen Field in Colorado Springs, Colorado. They were subsequently moved to Will Rogers Field in Oklahoma City to operate the reconnaissance variant of the Consolidated B-24 Liberator which was designated the F-7. Prior to the creation of an independent United States Air Force, the "F" designator was used for photo reconnaissance aircraft while the "P" (for Pursuit) was used for fighter aircraft. The first F-7s arrived in January 1943 as basic conversions of the B-24D Liberator which removed all bombing equipment and replaced with eleven cameras. All the defensive armament of the Liberator was retained. Most of the conversions to F-7s were done at Lowry Army Air Field in Denver, but additional examples were also converted by Northwest Orient Airlines at their Minneapolis maintenance base. Most of what the 24th did in Oklahoma City was the training of crews to prepare for deployment to the Pacific. Unlike other reconnaissance crews, though, the 24th CMS would be tasked with providing detailed aerial photography of the China-Burma-India area for the creation of detailed navigation maps as well as other types of maps needed for the war effort. 

The unit arrived at Guskhara, India in January 1944 with improved versions of the F-7 which were designated F-7A. The F-7A photo recon Liberator was based on the nose-turret equipped B-24J Liberator. A trimetrogon arrangement of cameras were mounted in the nose (an additional window was fitted in the lower side of the nose for the lateral cameras of the trimetrogon cameras) and a pair of vertical cameras for stereo-photography were fitted in the aft bomb bay (a pair of windows were fitted in the aft bomb bay). The additional windows were the identifying features of the F-7A. The forward bomb bay carried additional fuel tanks while the aft bay was sealed shut to provide a compartment for the camera technicians and environmental systems that kept the cameras and long rolls of film at a constant temperature. Again, like the original F-7 variant, the full defensive armament was retained. 

Developing the photos from a mapping mission.

The first missions to map the CBI area commenced in March 1944 in support of the US Army Air Forces' Tenth and Fourteenth Air Forces- it was the Fourteenth Air Force under General Claire Chennault that replaced the original American Volunteer Group which was also known as the "Flying Tigers". In addition, the 24th CMS also flew missions mapping Burma in support of the British 14th Army. While provisionally based in India, the squadron sent detachments of aircraft to operate from forward bases in China as well as more remote parts of India closer to the Burmese border. At the time, the only heavy bomber group based in China was the 308th Bombardment Group which flew B-24Js. The only logistical route for the support of the war effort in China came via the air route over the Himalayas called "The Hump". Frequently the B-24Js of the 308th BG had to be stripped of armament and fly their own bombs and fuel supplies from India over "Hump" the bases in China. It usually took three "Hump" missions by a single B-24J to transport the bombs and fuel needed for it to fly a single mission from China against Japanese targets all along the Pacific Coast of China, Vietnam, and Malaya. The photo-mapping F-7As of the 24th CMS also flew their own transport missions over the "Hump", with 182 "Hump" crossings made in 1944, often at well above maximum gross takeoff weight. Six F-7As were lost on these transport missions alone in 1944. 

Large areas of China lacked any maps at all, much to the frustration of the 308th BG. Many of the missions to map the interior of China were well over 2,500 miles in length. In addition, detailed mapping flights were made over Malaya (modern-day Malaysia), Vietnam, Thailand, and Burma. During the summer of 1944 the Japanese went on the offensive in central China to eliminate the forward bases of the 308th BG and numerous overflights of territory being contested were made to provide battlefield commanders accurate maps to blunt the Japanese offensive. Detailed maps were also made from overflights of all the Pacific ports of China that were being used by the Japanese to bring supplies to their forces in area. A less hazardous mission involved photo-mapping the entire supply routes from Allied bases in India over the "Hump" to Chinese forward bases. Air Transport Command's pilots benefited from a detailed map that covered a 50-mile wide strip from Calcutta all the way to Kunming in central China. 

24th CMS Consolidated F-7A Liberator. Note the camera windows.

By 1945 the 24th CMS had mapped 455,000 square miles of territory in India, Burma, Thailand, and Malaya. An additional 435,000 square miles of China were also mapped. The greatest challenge in the area for the 24th CMS wasn't Japanese resistance as the F-7As operating singly or in pairs were usually left alone but the weather. An astounding 50% of the missions flown were unsuccessful because of bad weather in the areas to be mapped!

Just prior to the end of the Pacific War the 24th CMS had a forward detachment also based in Clark AB in the Philippines to assist with mapping of that nation as the last of the Japanese resistance was mopped up. Following the Japanese surrender, another detachment was established in Sydney, Australia, to assist the Australians with the mapping of the continent which lasted well into 1946. By that point, the unit was converting to the photo reconnaissance version of the Boeing B-29 Superfortress, the F-13A. The unit returned stateside in late 1947 to Hamilton AFB in California before being disbanded in 1953 at Lake Charles AFB, Louisiana. 

Sources: B-24 Liberator Units of the CBI (Osprey Combat Aircraft No. 87) by Edward M. Young. Osprey Books, 2011, p88-89. Combat WWII Squadrons of the United States Air Force: The Official Military Record of Every Active Squadron, edited by M. Maurer and the USAF Historical Division. Smithmark Publishers, 1992, p126-127. Photos: University of Chicago, Mark Styling (illustrator for the Osprey title).

When Colonel William J. Donovan formed the Office of Strategic Services (OSS), the CIA's antecedent organization in World War II, one of his first acts was to create a research and development branch headed by noted chemist Dr. Stanley Lovell. Lovell's R&D section of the OSS was composed of engineers, chemists and other technical professions he recruited from American industry and academia. Their purpose was to develop the tools and weapons not just for espionage but for unconventional warfare and weaponry.

One of the projects the OSS examined was suggested by a civilian dentist, Lytle Adams. Project X-Ray sprang from Adams' suggestion that small incendiary device could be attached to a bat. These bats would be released over Japan and the bats would roost in inaccessible places on buildings that were predominantly of wood construction. After a time-delay, the incendiary would go off, and fires would break out all over Japanese cities.

Louis Frieser, the inventor of napalm, created a one ounce timed-delay incendiary that was attached to the Mexican free-tailed bat, a prolific bat species found throughout the American Southwest. The bat bomb itself had forty trays, each holding 26 bats. Dropped from at least 5,000 feet, the bomb descended by parachute before the casing opened at 1,000 feet, dispersing the bats. By dropping the bombs at dawn, the bats would instinctively seek shelter in buildings. It was estimated that 10 Consolidated B-24 Liberators each carrying 100 bat bombs staging from Alaska could release over 1 million bats over the industrial cities around Tokyo and Osaka.

Tests conducted at Carlsbad Army Air Field in New Mexico resulted in the burning down (unintentionally) of several new hangars at the base. Further tests validated the concept but by 1944 the project was canceled it as it wouldn't be ready by 1945.

Source: Spycraft- The Secret History of the CIA's Spytechs, from Communism to Al-Qaeda by Robert Wallace and H. Keith Melton. Plume Books, 2009, 11-13.

The First Serious Proposal for Air Refueling on a Combat Mission

The first serious proposal to use air-to-air refueling in a combat mission came in early 1942 just weeks after the Japanese attack on Pearl Harbor. The United States wanted to strike back as expeditiously possible at Japan and early efforts focused on the US Army Air Corps inviting the British firm Flight Refueling Ltd to send some engineering staff to Wright Field in Dayton, Ohio, to discuss converting the Consolidated B-24 Liberator into a tanker and the Boeing B-17 Flying Fortress into a receiver aircraft. The USAAC (soon to become the US Army Air Forces) ordered on set of inflight refueling equipment similar to what Flight Refueling used in its 1939 trans-Atlantic trials.

With the assistance of Flight Refueling engineers, Pennsylvania Central Airlines modified a B-24 and a B-17 with the refueling equipment (PCA would later be renamed Capital Air Lines which was then absorbed by United Air Lines in 1961). By April 1943 the first flight trials were conducted at Eglin Field in Florida. By this time, however, the Doolittle raid on Tokyo had already taken place but the USAAF wanted to further examine the feasibility of air refueling in strategic bombing operations.

Using Flight Refueling's grapple method, the B-17 receiver trailed a hauling line with a weight and hook at the end. The B-24 tanker approached from the side and below and deployed a contact line that crossed over the hauling line of the B-17 and engaged the hook. The B-24 tanker then moved above the B-17, pulling in the hauling line with the contact line. The refueling hose was then attached to the hauling line and it was then pulled down to the B-17 which had a refueling receptacle in the tail gunner's position and refueling commenced.

At the conclusion of the tests, the B-17's range with a full bomb load could be extended to 5,800 miles (compared to its standard 2,000 mile range). Plans were conceived to have B-17s based in the Aleutian Islands and strike Japan with air-refueling, proceed on to bases in China and then reverse the process. However, the time needed convert and train sufficient bombers and crews to sustain a strategic bombing campaign on Japan were seen as too long with Boeing getting ready to produce the B-29 Superfortress and Admiral Nimitz's successes in the Central Pacific in securing possible islands to use as bomber bases.

Source: History of Air-to-Air Refueling by Richard M. Tanner, MBE. Pen & Sword Books, 2006, p24.

Initially deemed unsuitable as night bombers by the RAF, the first Consolidated LB-30 Liberators were found with their long range to be ideal in the transport role. In mid-1941 the North Atlantic Return Ferry Service began to bring RAF flight crews to Canada where they would pick up US Lend-Lease aircraft to fly back to Europe. As a result, the Liberator was the first aircraft to make the North Atlantic crossing carrying passengers on a regular service. On 24 September 1941 BOAC took over the North Atlantic services from the RAF and also took on the Liberator transports.

The BOAC Liberators wore either civil registrations or RAF roundels but could be identified by the Speedbird logo on the nose of the aircraft. Flights connected Prestwick with St-Hubert in Quebec via Gander, Newfoundland. In January 1942 the first BOAC Liberators started passenger services to Cairo (via North Africa) and in the following year passenger services extended to Moscow (via North Africa and Iran to avoid occupied Europe).

By 1947 the RAF had already withdrawn its own Liberators from service but BOAC continued use of the Liberator in cargo services London and Montreal via Prestwick and Gander. From 4 February to 28 May 1948 BOAC inaugurated nonstop Liberator service between London and Montreal using inflight air-refueling. Flight Refueling Limited, an early pioneer in aerial refueling, purchased four Avro Lancastrians from Trans-Canada Airlines and converted them into refueling tankers. Two of them were based in Shannon, Ireland, and the other two were based in Newfoundland. The Liberators flying eastbound needed only a single refueling usually about 200 miles east of Gander. Flying westbound, two refuelings were needed to fly against prevailing winds- the first one 200 miles west of Shannon and the second one in the vicinity of Goose Bay, Labrador.

Of forty-five refuelings, only three were aborted- one due to radar and heating problems in the tanker, one due to fuel transfer problems and a third one due to a nervous BOAC captain who refused to carry out the aerial rendezvous! Despite the success of the trials and Flight Refueling's attempt to convince BOAC that aerial refueling was feasible for civilian flights, BOAC instead opted to use Lockheed Constellations and Boeing Stratocruisers to carry out nonstop North Atlantic services.

Source: International Air Power Review, Volume 15. AIRtime Publishing, 2005, "RAF Liberators at War- Part 1: UK-based Operations" by Jon Lake, p160-161, 172-173.

Dr. Forrest Bird, head of a biomedical engineering corporation based in Palm Springs, bought a Consolidated PBY Catalina (specifically it was a Canadian-built PBY-5 Canso) that in 1968 he had modified into a four-engined configuration called the Bird Innovator. Outboard of the existing radial engines were added nacelles accommodating 360-horsepower Lycoming piston engines driving Hartzell three bladed propellers. Though the speed increase from the Lycomings was modest, the real improvement came from the propwash of the new additonal engines which, in effect, acted to energize the airflow across the outer wings of the Catalina which were notorius for being sluggish particularly in engine out situations.

The Bird Innovator also had strengthened wings and a taller fin and rudder as well. The engineer's controls were also moved to the cockpit to allow the aircraft to be operated by a single pilot. After passing through various owners, the aircraft in 1997 was returned back to its original layout.

Source: General Dynamics Aircraft and their Predecessors by John Wegg. Putnam Aeronautical Books/Naval Institute Press, 1990, p78.

The introduction of the MAD sensor (magnetic anomaly detection) posed a problem with the current anti-submarine weapon of the day, the depth charge or depth bomb. US Navy squadron VP-63 got its Consolidated PBY-5A Catalina flying boats modified with MAD stingers in 1942. As the Catalina had to fly low over the surface of the water to detect the magnetic signature of a submerged U-boat, by the time the depth bomb was released, the aircraft's forward motion would carry the bomb ahead of the intended target.

As a solution, scientists at CalTech designed the "Retrorocket" which was an air-launched rocket based on the ship-launched Hedgehog antisubmarine rocket. The retrorocket weight 65 lbs with a 35 lb warhead and solid rocket motor in the tail with a ring fin assembly for stability. The retrorocket was mounted under the Catalina's wings pointed aft. Once the MAD sensor detected the U-boat, the rockets fired aft to fall vertically at the point where it had been fired as the forward facing rocket canceled out the forward speed of the launching aircraft.

Flying only 100 feet above the sea, the Catalinas of VP-63 based at Port Lyautey, Morocco, partrolled the Strait of Gibraltar to prevent U-boats from reinforcing the Mediterranean. In 1944 U-761 was the first casualty of the MAD Cats of VP-63. U-618 tried to run the Strait but turned back to France. Then U-392 tried to run the gauntlet and fell to a combined attack by MAD Cats and surface ships. Three U-boats would later sneak in successfully by avoiding the deep water channels altogether. U-731 then was sunk again and following that, one more U-boat made it past the strait, but the German effort proved excessively costly as by this point in the war every U-boat was valuable.

Source: Aeroplane, October 2009. "Mad Cats and Mousetraps" by Dr. Alfred Price, p17-21.