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2 September 1944

Lt. (j.g.) George H.W. Bush, USNR, VT-51, in cockpit of TBM-1C Avenger Bu.No. 46214, USS San Jacinto (CVL-30), 1944. (U.S.Navy)

2 September 1944: Lieutenant (Junior Grade) George Herbert Walker Bush, United States Naval Reserve, led a flight of four TBF/TBM Avenger torpedo bombers of Torpedo Squadron 51 (VT-51), from the Independence-class light aircraft carrier USS San Jacinto (CVL-30), against a radio transmission station on the island of Chichi-Jima.

The Avenger had a crew of three. Along with Lt (j.g.) Bush were Lt. (j.g.) William G. White, USNR, gunner, and radio operator ARM 2/c John Lawson Delaney, USNR.

Undated photo of future United States President George H.W. Bush as a United States Navy pilot seated in the cockpit of an Avenger. (U.S. Navy)

Each airplane was armed with four 500-pound¹ general purpose bombs. The flight was joined by eight Curtiss-Wright SB2C Helldiver dive bombers of VB-20, escorted by twelve Grumman F6F-5 Hellcat fighters of VF-20, from USS Enterprise (CV-6).

Chichi-Jima is the largest island in the Ogasawara Archipelago of the Bonin Islands, approximately 150 miles (240 kilometers) north of Iwo Jima and 620 miles (1,000 kilometers) south of Tokyo, Japan. The United States Hydrographic Survey described the island in 1920 as “very irregular in shape,” approximately 4¼ miles (7.2 kilometers) long and 2 miles (3.2 kilometers) wide. The area of the island is presently given as 23.45 square kilometers (9.05 square miles). Its highest point is 326 meters (1,070 feet) above Sea level. The island has a small sea port where midget submarines were based beginning in August 1944. Chichi-Jima was heavily garrisoned with 20,656 Imperial Japanese Army and Navy personnel, and 2,285 civilian workers.²

A Curtiss-Wright SB2C Helldiver over Chichi Jima. (U.S. Navy)

Lieutenant Bush’s flight was scheduled for a time over target of 0825–0830. They encountered heavy antiaircraft fire and Bush’s Avenger was hit. With the torpedo bomber on fire, Bush continued the attack and later reported good results. Unable to return to the aircraft carrier, he flew away from the island to limit the risk of capture of the crew by the enemy when they bailed out.

Bush and one other crewman (which one is not known) bailed out. While Bush parachuted safely, the second crewman’s parachute never opened. The third crewman went down with the airplane. Both Lieutenant White and Radioman Delaney were killed.

The Gato-class fleet submarine USS Finback (SS-230) was stationed near the island on lifeguard duty during the attack. At 0933, Finback was notified of an aircraft down nine miles northeast of Minami-Jima.  Escorted by two F6F fighters, the submarine headed for the location. At 1156, Finback picked up Lt. Bush, floating in his life raft. A search for White and Delaney was unsuccessful. Their bodies were not recovered.

Lt. (j.g.) George H. W. Bush, USNR, in inflatable raft, is rescued by the crew of USS Finback (SS-230), 2 September 1944. (U.S. Navy)

(Later that same day, Finback, while submerged, towed a second pilot and his life raft away from Magane-Iwa, as he held on to the sub’s periscope.)

Lieutenant Bush and the other rescued pilots remained aboard for the remainder of Finback‘s war patrol (her tenth), and were then returned to Pearl Harbor. In November he rejoined San Jacinto for operations in the Philippines.

Gato-class fleet submarine USS Finback (SS-230) off New London, Connecticut, 7 March 1949. (U.S. Navy)

George Herbert Walker Bush was born at Milton, Massachusetts, 12 June 1924, the son of Prescott Sheldon Bush and Dorothy Walker Bush. He attended high school at the Phillips Academy in Andover, Massachusetts.

One day after his 18th birthday, 13 June 1942, Bush enlisted as a seaman, 2nd class, in the United States Naval Reserve. He was appointed an aviation cadet and underwent preflight training at the University of North Carolina, Chapel Hill. He was honorably discharged 8 June, and commissioned as an ensign, United States Naval Reserve, 9 June 1943. At the age of 19 years, 2 days, he became the youngest Naval Aviator in history. (His age record was broken the following month by Ensign Charles Stanley Downey, who was commissioned 16 July 1943 at the age of 18 years, 11 months, 14 days.)

Aviation Cadet George H. W. Bush, USNR, 1942. (U.S. Navy)

Ensign Bush continued flight training at NAS Pensacola, Florida, and then the Carrier Qualification Training Unit, NAS Glenville, Illinois. After training with the Atlantic Fleet, Ensign Bush was assigned to Torpedo Squadron Fifty-One (VT-51), in September 1943. He was promoted to lieutenant (junior grade), 1 August 1944.

After leaving San Jacinto, Bush was assigned to NAS Norfolk, Virginia, from December 1944 to February 1945. He then joined Torpedo Squadron Ninety-Seven (VT-97) and then VT-153.

Lieutenant (j.g.) Bush was released from active duty on 18 September 1945, retaining his commission. He was promoted to lieutenant 16 November 1948. On 24 October 1955, Lieutenant Bush resigned from the U.S. Navy.

During World War II, George H. W. Bush flew 58 combat missions. He flew a total of 1,221 hours and made 126 carrier landings. He was awarded the Distinguished Flying Cross, the Air Medal with two gold stars (three awards), and the Presidential Unit Citation.

He would later become the forty-first President of the United States of America.

Grumman TBF or General Motors TBM Avengers over Wake Island, 1943. (U.S. Navy)

The airplane flown by Lt. (j.g.) Bush on 2 September 1944 was a General Motors TBM-1C Avenger torpedo bomber, Bu. No. 46214. This was a licensed variant of the Grumman TBF-1C Avenger, built by the General Motors Corporation Eastern Aircraft Division at Linden, New Jersey.

The Avenger was designed by Robert Leicester Hall, Chief Engineer and Test Pilot for the Grumman Aircraft Engineering Corporation, Bethpage, New York. The prototype XTBF-1 made its first flight 1 August 1941. It was a large single-engine aircraft, operated by a crew of three (pilot, radio operator and ball turret gunner). It was equipped with folding wings for storage on aircraft carriers. Production of the torpedo bomber began with the opening of a new manufacturing plant, Sunday, 7 December 1941. The first production Avenger was delivered to the U.S. Navy in January 1942.

The TBF-1 and TBM-1 were 40 feet, 11 inches (12.471 meters) long, with a wingspan of 54 feet, 2 inches (16.510 meters) and overall height of 16 feet, 5 inches (5.004 meters). The airplane had an empty weight of 10,545 pounds (478 kilograms), and its maximum gross eight was 17,895 pounds (8,117 kilograms). The Avenger was the largest single-engine aircraft of World War II.

LCDR Albert B. Cahn, USN, gives the take-of signal to a General Motors TBM-1C Avenger of Torpedo Squadron 51 (VT-51) aboard the light aircraft carrier USS San Jacinto (CVL-30), during exercises on 16 May 1944. (U.S. Navy)

The Avenger was powered by one of several variants of the Wright Aeronautical Division Cyclone 14 (R-2600): GR2600B698 (R-2600-8 and -8A); GR2600B676 (R-2600-10); and 776C14B31. The R-2600 was series of air-cooled, supercharged, 2,603.737-cubic-inch-displacement (42.688 liter), two-row 14-cylinder radial engines. The engines used in the Avengers all had a compression ratio of 6.9:1, supercharger ratios of 7.06:1 and 10.06:1, and propeller gear reduction ratio of 0.5625:1.

The R-2600-8, -8A and -10 had Normal Power ratings of 1,500 horsepower at 2,400 r.p.m. at Sea Level, and 1,700 horsepower at 2,600 r.p.m. for takeoff. The R-2600-20 was rated at 1,600 horsepower at 2,400 r.p.m., and 1,900 horsepower at 2,800 horsepower, respectively.

Dimensions and weights varied. The R-2600-8 and -8A were 64.91 inches (1.649 meters) long. The -10 was 74.91 inches (1.903 meters) long, and the length of the -20 was 66.08 inches (1.678 meter). The R-2600-8 and 8A and -10 were 54.26 inches (1.378 meters) in diameter. The -20 was 54.08 inches (1.374 meters). The -8 and -8A both weighed 1,995 pounds (905 kilograms). The -10 weighed 2,115 pounds (959 kilograms) and the -20 weighed 2,045 pounds (928 kilograms).

The engines drove a three-bladed Hamilton Standard Hydromatic constant-speed propeller.

The TBF/TBM had a cruise speed of 147 miles per hour (237 kilometers per hour) and maximum speed of 276 miles per hour (444 kilometers per hour) at 16,500 feet (5,029 meters). The service ceiling was 30,100 feet (9,174 meters). Its maximum range was 1,010 miles (1,625 kilometers).

The Avenger was armed with one air-cooled Browning AN-M2 .50-caliber machine gun mounted in each wing, firing forward. Another .50-caliber machine gun was installed in an electrically-operated dorsal ball turret. In the ventral position was a Browning M2 .30-caliber aircraft machine gun in a flexible mounting.

The primary weapon of the Avenger was carried in an enclosed weapons bay. It could be armed with one Mk. 13 aerial torpedo, ³ or up to 2,000 pounds (907 kilograms) of bombs.

A Grumman TBF-1 Avenger 4-T-2 of Torpedo Squadron Four (VT-4) drops a Mk. 13 aerial torpedo, circa 1942. Following the destruction of Torpedo Eight at the Battle of Midway, aerial torpedo attacks were rarely used by the U.S. Navy. (U.S. Navy)

The Grumman Aircraft Engineering Corporation produced TBF Avengers from Early 1942 until 1943, when production was taken over by the General Motors Corporation Eastern Aircraft Division. Grumman produced 2,290 TBFs, while Eastern built 9,836 TBMs.

Lieutenant Bush’s aircraft carrier, USS San Jacinto (CVL-30), was an Independence-class light carrier. It had been started by the New York Shipbuilding Corporation as a Cleveland-class light cruiser, USS Newark (CL-100), but was converted during construction. Construction took 11 months and the ship was launched 26 September 1943. It was commissioned 15 November 1943.

The carrier was 622.5 feet (189.7 meters) long, with a beam of 71.5 feet (21.8 meters) and draft of 26 feet (7.9 meters). It had a full load displacement of 15,100 long tons (16,912 short tons, or 15,342 metric tons). The ship was powered by steam turbines producing 100,000 horsepower and driving four shafts. San Jacinto was capable of a maximum 31.6 knots (36.4 miles per hour, or 58.5 kilometers per hour).

San Jacinto had a complement of 1,549 men, and carried 45 airplanes. For defense, it was armed with 28 Bofors 40 millimeter anti-aircraft guns and 40 Oerlikon 20 millimeter autocannon.

San Jacinto was decommissioned 1 March 1947 and was later scrapped.

USS Independence (CVL-30), late 1943. (U.S. Navy)

On 7 October 2006, the tenth and final Nimitz-class supercarrier was christened USS George H.W. Bush (CVN-77) in honor of President Bush’s service to his country.

USS George H. W. Bush (CVN-77). (U.S. Navy)

¹ The most common U.S. 500-pound general purpose bomb of World War II was the AN-M64. Nominally a 500-pound (227 kilogram) bomb, the munition actually weighed from 516.3 to 535.4 pounds (234.2 to 242.9 kilograms), depending on the explosive used. It contained 266 pounds (120.7 kilograms) of TNT, or 258.5 pounds (117.3 kilograms) of a 50/50 TNT and Amatol mixture. For easy identification, these were marked with a single 1-inch (2.54 centimeter) wide yellow band painted at the nose and tail. Composition B bombs, which were marked with two yellow identification bands, contained 272.7 pounds (123.7 kilograms) of explosive, while the heaviest was filled with 278.3 pounds (126.2 kilograms) of Tritonal. This variant was marked with three yellow bands. The bomb, without fins or fuses, was 36 inches (0.914 meters) long. The overall length was 59.16 inches (1.503 meters), including nose and tail fuses. The maximum diameter was 10.9 inches (0.277 meters).

² Personnel numbers as of 3 September 1945.

³ The U.S. Navy Torpedo, Mark 13, was a gyroscopically-steered single-speed anti-ship torpedo designed to be dropped from aircraft. It was 13 feet, 8.55 inches (4.180 meters) long, 1 foot, 10.42 inches (0.570 meters) in diameter and weighed 1,949 pounds (884 kilograms) ± 20 pounds (9 kilograms). The warhead contained a 400 pound (181 kilogram) TNT explosive charge.  The Mk. 13 was driven by a two-stage alcohol-fueled geared steam turbine, turning 10,983 r.p.m., with the coaxial counter-rotating propellers turning 1,150 r.p.m. It was capable of running at 33.5 knots (38.6 miles per hour, or 62.0 kilometers per hour), with a range of 6,300 yards (5.8 kilometers). This same type torpedo was used by the U.S. Navy’s PT boats late in the war.

Thanks to regular TDiA reader Joolz Adderly for suggesting this topic.

© 2017, Bryan R. Swopes

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2 September 1937: Grumman F4F Wildcat

Grumman XF4F-2, Bu. No. 0383, in flight. (Grumman Aircraft Engineering Corporation via World War Photos)

2 September 1937: First flight, Grumman XF4F-2 Bu. No.¹ 0383, a prototype fighter for the United States Navy and Marine Corps. The airplane was designed by Grumman’s Chief Engineer, Robert Leicester Hall.

Grumman XF4F-2 Bu. No. 0383. (Grumman Aircraft Engineering Corporation via World War Photos)

The prototype was damaged when it nosed over during a forced landing, 11 April 1938. The pilot, Lieutenant Gurney, was not injured. 0383 was rebuilt as an XF4F-3. The Navy ordered the fighter into production as the F4F-3 Wildcat. XF4F-3 0383 was destroyed in an accident, 16 December 1940. The pilot was killed.

Grumman XF4F-2 Bu. No. 0383 dead-stick landing accident near Naval Aircraft Factory, Philadelphia, 11 April 1938. (Grumman Aircraft Engineering Corporation)

The Grumman F4F-3 Wildcat was a single-engine, single-place, mid-wing monoplane fighter designed for operation from aircraft carriers. F4F-4 and later variants had folding wings for a smaller “foot print” while stored aboard.

Grumman XF4F-2. (The hoisting chains are air-brushed out.) (Grumman Aircraft Engineering Corporation)
Grumman XF4F-3 Wildcat, Bu. No. 0383, circa April 1939. The vertical fin is taller and squared-off. (United States Navy, Naval History and Heritage Command NH 97481)

The F4F-3 Wildcat was 28 feet, 10½ inches (8.801 meters) long with a wingspan of 38 feet, 0 inches (11.582 meters). The height over the propeller with the airplane in 3-point attitude was 11 feet, 9 inches (3.581 meters). The wings had a total area of 260 square feet (24.16 square meters). They had 0° incidence and no leading edge sweep. Thewings had 5° dihedral. The F4F-3 had an empty weight of 5,293 pounds (2,401 kilograms) and gross weight of 7,432 pounds (3,371 kilograms) with 147 gallons (556 liters) of gasoline.

Grumman F4F-3 Wildcat. (Grumman Aircraft Engineering Corporation)

The F4F-3 was powered by an air-cooled, supercharged, 1,829.39-cubic-inch-displacement (29.978 liter) Pratt & Whitney Twin Wasp SSC7-G (R-1830-86) two-row, 14-cylinder radial engine with a compression ratio of 6.7:1. The R-1830-86 had a normal power rating of 1,100 at 2,550 r.p.m., from Sea Level to 3,300 feet (1,006 meters), and 1,000 horsepower at 2,550 r.p.m. at 19,000 feet (5,791 meters). It was rated at 1,200 horsepower at 2,700 r.p.m. for takeoff. The engine turned a three-bladed Curtiss Electric propeller with a diameter of 9 feet, 9 inches (2.972 meters) through a 3:2 gear reduction. The R-1830-86 was 4 feet, 0.19 inches (1.224 meters) in diameter, 5 feet, 7.44 inches (1.713 meters) long, and weighed 1,560 pounds (708 kilograms).

Grumman XF4F-3 Wildcat Bu. No. 0383. (Grumman Aircraft Engineering Corporation)

The F4F-3 had a maximum speed of 278 miles per hour (447 kilometers per hour) at Sea Level, and 330 miles per hour (531 kilometers per hour at 19,000 feet (5,791 meters). It could climn to 20,000 feet (6,096 meters) in 7.6 minutes. The service ceiling was 30,500 feet (9,296 meters) and its maximum range was 1,280 miles (2,060 kilometers).

Grumman F4F-3 Wildcat, Bu. No. 1844 at Bethpage, New York, awaiting delivery to the U.S. Navy. (Grumman Aircraft Engineering Corporation)

The F4F-3 Wildcat was armed with four Browning AN-M2 .50-caliber machine guns. Later variants would have six guns.

The F4F Wildcat was produced by Grumman and the General Motors Corporation Eastern Aircraft Division as the FM-1. Grumman shifted to production of teh F6F Hellcat in early 1943. GM continued to build Wildcats until the end of the War. A total of 7,885 were built.

Grumman F4F-3 Wildcat Bu. No. 1844. (Grumman Aircraft Engineering Corporation)
Grumman F4F-3 Wildcat Bu. No. 1844. (Grumman Aircraft Engineering Corporation)
Grumman F4F-3 Wildcat, Bu. No. 1844. (Grumman Aircraft Engineering Corporation)
Grumman F4F-3 Wildcat.(Grumman Aircraft Engineering Corporation)
Grumman F4F-3 Wildcat Bu. No. 1845, Summer 1940. (Grumman Aircraft Engineering Corporation)
Grumman F4F-3 Wildcat, circa 1942. (Smithsonian Institution National Air and Space Museum NASM 2009-9043)
Grumman F4F-3 Wildcat in three-color camouflage (LIFE Magazine)
Grumman F4F-3 Wildcat (LIFE Magazine)
Grumman F4F-3 Wildcat Bu. No. 2638, Bethpage, L.I., N.Y. This airplane was assigned to NACA Langley from 4 April–22 August 1941. Chief Engineer Robert Leicester Hall, front, kneeling, second from left (dark pullover sweater with light, open collar). Test pilot Corky Meyer in cockpit). (Grumman Aircraft Engineering Corporation)
Corky Meyer demonstrates deployment of life raft, 19 November 1942. (Grumman Aircraft Engineering Corporation)

¹ “Bu. No.” is the abbreviation for the Navy’s Bureau of Aeronautics serial number assigned to each aircraft.

© 2019, Bryan R. Swopes

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1 September 1946

Alvin M. “Tex” Johnston with the Thompson Trophy and the Allegheny-Ludlum Trophy, 1946 National Air Races. (San Diego Air and Space Museum Archives)

1 September 1946: Just one year after World War II came to an end, the National Air Races returned to Cleveland, Ohio. Grandstands were set up at the site of the Fisher Body Aircraft Plant No. 2, where assemblies for B-25 and B-29 bombers had been produced.

The Thompson Trophy Race was one of the most popular events because it was in view of the crowds. Sponsored by Thompson Products Company (the predecessor of TRW), it was a ten-lap pylon race flown at low altitude around a 30-mile (48.3 kilometers) course. There were two divisions. The R Division was for airplanes with reciprocating engines, and the J Division was for turbojet powered airplanes.

The National Air Races 4-pylon course, flown in 1947, 1947 and 1948. (airrace.com)

The race course was laid out as a parallelogram, with two 10-mile (16.1 kilometer) sides, and two 5-mile (8.0 kilometer) sides. There were two 75° turns and two 105° turns.

In addition to the Thompson Trophy, the race winner would receive $20,000 in prize money (about $342,400 in 2018 U.S. dollars). There were additional $2,000 prizes for the leader of each lap. A pilot who set a speed record during the race would win the Allegheny-Ludlum Trophy and $2,000.

Entrants for the 1946 race included many well-known air racers, test pilots and combat pilots. They included Cook Cleland, a U.S. Navy dive bomber pilot and test pilot; Woodrow W. (“Woody”) Edmondson, an aerobatic pilot; Howard Clifton (“Tick”) Lilly, a test pilot for the National Advisory Committee for Aeronautics (NACA, predecessor of NASA); Alvin Melvin (“Tex”) Johnston, an experimental test pilot with the Bell Aircraft Corporation; Anthony W. (“Tony”) LeVier, Chief Engineering Test Pilot for the Lockheed Aircraft Corporation, and an experienced pylon racer; Earl Hill Ortman, test pilot for Douglas Aircraft Company, and also an experienced racer; Howard L. Pemberton; Bruce Raymond; Robert Swanson; Charles (“Chuck”) Tucker, who had flown P-40s with the “Flying Tigers” in China, and an Army Air Corps test pilot; George Schwarz Welch, the Army Air Corps hero of Pearl Harbor, and test pilot for North American Aviation, Inc.; and Sylvester Joseph (“Steve”) Wittman, an aircraft designer and air racer.

Before the war, the races used specially-constructed racing aircraft and production civil aircraft. Following the war, the expense of developing a purpose-built, competitive air racer was no longer feasible, so surplus military fighters were used.

Of the twelve airplanes competing in the 1946 Thompson Race, there was one Bell Aircraft Corporation P-39Q Airacobra; four Bell P-63 Kingcobras; one Goodyear Aircraft Corporation FG-1D Corsair (a licensed variant of the Vought-Sikorsky F4U Corsair); a Lockheed Aircraft Corporation P-38L Lightning; and five North American Aviation, Inc., P-51D Mustangs.

Jack Woolams, Chief Test Pilot for Bell Aircraft Corporation, Experimental Test Pilot Tex Johnston, and Bell’s Chief Engineer, Robert Morris Stanley, had determined that a properly prepared Bell P-39 Airacobra could outrun and outfly a North American Aviation P-51 Mustang in the Thompson race.

A Bell Aircraft mechanic was sent to inspect surplus P-39s in storage at Ponca City, Oklahoma. He selected two nearly-new P-39Q Airacobras, each with less than 50 hours flight time. Woolams and Johnston paid $3,000 for the two fighters and they were flown back to the Bell plant at Buffalo, New York.

Jack Woolams’ Cobra I was a P-39Q-10-BE, U.S. Army Air Corps serial number 42-20733. Tex Johnston’s Cobra II was also a P-39Q-10-BE, 42-20869 (Bell serial number 26E-324).

The Bell P-39 Airacobra was a single-engine, single-place low-wing monoplane with retractable tricycle landing gear. An Allison V-1710 V-12 engine was mounted behind the cockpit in an unusual mid-engine configuration, with a drive shaft passing under the cockpit floor and turning the propeller through a remotely-mounted 1.8:1 gear reduction unit. This allowed the fighter to be armed with a large 37 mm autocannon which fired through the propeller hub.

Bell P-39Q-20-BE Airacobra 44-3887 at the National Museum of the United States Air Force)

The P-39Q was the final production version of the Airacobra. It was 30 feet, 2 inches (9.195 meters) long with a wingspan of 34 feet, 0 inches (10.363 meters) overall height of 12 feet, 5 inches (3.785 meters). The wings’ angle of incidence was +2° and there was 4° 0′ dihedral. The total wing area was 213 square feet (19.78 square meters). The horizontal stabilizer had +2° 15′ incidence and no dihedral.   The P-39Q had an empty weight of 5,692 pounds (2,704 kilograms), and maximum gross weight of 8,350 pounds (3,787 kilograms).

The production P-39Q was powered by a liquid-cooled, supercharged, 1,710.597-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710-E19 (V-1710-85) single overhead camshaft (SOHC) 60° V-12 engine with four valves per cylinder and a compression ratio of 6.65:1. The V-1710-85 had a continuous power rating of 810 horsepower at 2,600 r.p.m. at Sea Level, and 1,000 horsepower at 2,600 r.p.m. at 14,000 feet (4,267 meters). The engine’s takeoff power rating was 1,200 horsepower at 3,000 r.p.m., and its military power rating was 1,125 horsepower at 3,000 r.p.m., at 14,600 feet (4,450 meters). 100/130 octane aviation gasoline was required. The Allison drove a three-bladed Aeroproducts Division A632S-C1 hydraulically-operated constant-speed propeller with a diameter of 11 feet, 7 inches (3.531 meters) through a 2.23:1 gear reduction. The V-1710-85 was 16 feet, 2.00 inches (4.928 meters) long, 3 feet, 1.56 inches (0.954 meters) high, and 2 feet, 5.28 inches (0.744 meters) wide. It weighed 1,435 pounds (651 kilograms).

Cutaway illustration showing the unusual mid-engine arrangement of the Bell P-39 Airacobra. (Allison Division of General Motors)

The Bell P39Q-10-BE had a maximum speed of 385.0 mph (619.6 kilometers per hour) at 11,000 feet (3,353 meters). Its service ceiling was 34,300 feet (10,455 meters), absolute ceiling, 35,700 feet (10,881 meters), and its range was 1,075 miles (1,730 kilometers).

The P-39Q was armed with one Browning M4 37 mm autocannon with 30 rounds of explosive ammunition, and four Browning AN-M2 .50-caliber machine guns, with two in the nose with 200 rounds per gun, and one mounted under each wing in pods with 300 rounds per gun. The M4 cannon fired a 1.34 pound (608 grams) high-explosive shell at 2,000 feet per second (610 meters per second). The gun had a rate of fire of 150 rounds per minute.

The Bell Aircraft Corporation built 9,558 P-39s. 4,905 of these were P-39Qs. 705 were the P-39Q-10-BE variant.

Jack Woolams (left) and Tex Johnston pose with their air racers, Cobra I and Cobra II, at the Bell Aircraft Corporation plant, August 1946. (airrace,com)

Bell Aircraft provided hangar space for the two Airacobras, and assigned an engineer and five mechanics to the project. Cobra I was painted red with black accents. It was issued Civil Aeronautics Administration experimental registration NX92847. Its race number, 75, was painted on the wings and fuselage. Cobra II was painted yellow with black trim, and registered NX92848. Its race number was 84.

Both airplanes were stripped of armament, armor and self-sealing fuel tanks. The landing gear was modified to reduce its retraction time from 22 seconds to just 4 seconds. The standard fabric-covered ailerons, rudder and elevators were covered with sheet aluminum. Adjustable trim tabs were deleted. Gyroscopic instruments were removed. The pitot tube was moved from the left wing tip and placed on a long boom projecting through the propeller hub. Thin, light-weight Goodyear fuel bladders were installed, not only reducing weight, but increasing the Airacobras’ fuel capacity by 10%. The roll-down side windows of the P-39 were replaced by fixed Plexiglas panels.

Bell P-39Q-10-BE NX92848, Cobra II, Tex Johnston’s Thompson Trophy Race winner. (San Diego Air and Space Museum Archives)

Engineers at Allison recommended that a modified Allison XV-1710-135 (E31) engine be used for the two racers. The modified engines used an increased-diameter supercharger impeller and undersized pistons to reduce cylinder wall friction. Using 140-octane Mobil aviation gasoline, they produced 2,000 horsepower at 3,200 r.p.m. with 86 inches (291 kilopascals) of manifold pressure. The high power output required that the engine be provided with a continuous injection of a precisely-measured water and ethyl/methyl alcohol solution when operating above 57 inches (193 kilopascals) of manifold pressure. An 85 gallon (322 liter) tank for the injection mixture was placed in the nose.

Tex Johnston’s Thompson Trophy-winning Bell P39Q Airacobra, “Cobra II.” (San Diego Air and Space Museum Archives)

The increased power of the modified XV-1710-135 required that the P-39’s standard three-bladed propeller be replaced by a four-bladed unit from the P-63 Kingcobra. This was an Aeroproducts A624S constant-speed propeller with hollow steel blades. Its diameter was 11 feet, 0 inches (3.531 meters). The propeller gear reduction ratio remained the same, at 2.23:1, as did the remote gear box, at 1.8:1.

Allison V-1710-E19 (V-1710-85) with extension drive shaft and remote propeller drive gear unit. (Allison Division of General Motors)

The V-1710-E31 was longer and heavier than the -E19 because of an outboard reduction gear box. It was 17 feet, 4.00 inches (5.283 meters) long, 3 feet, 0.75 inches (0.933 meters) high, with the same 2 foot, 5.28 inch (0.744 meters) width. It weighed 1,500 pounds (680 kilograms).

Jack Woolams’ P-39 Cobra I leads a P-51D Mustang around a pylon turn during qualifying, August 1946. (LIFE Magazine via Jet Pilot Overseas)

When race qualifications were held, Tex Johnston was placed first with his yellow Cobra II. His average speed was 409.091 mph (658.368 kilometers per hour). George Welch was second with his P-51D, number 37. Jack Woolams and Cobra I were third.

Jack Valentine Woolams, Chief Experimental Test Pilot, Bell Aircraft Corporation. (John Trudell/Ancestry)

Jack Valentine Woolams was killed on 30 August, two days before the race, when his Cobra I crashed into Lake Ontario while returning to the Bell plant for an engine change. The Airacobra’s windshield may have collapsed at over 400 miles per hour (644 kilometers per hour).

The Thompson Trophy Race was held on Sunday, 1 September 1946. Tex Johnston, leading the field, took off and retracted his landing gear, climbing to 300 feet (91 meters). As he approached the first turn, he rolled Cobra II into a 4G turn (75.5° angle of bank) and dove to 60 feet (18 meters). As he made the turn, he was already pulling far ahead of the other racers.

George Welch dropped out when his Merlin engine began overheating. Tony LeVier’s P-38 Lightning, race number 3, held on to second place. By the ninth lap, Tex Johnston was passing the airplanes at the back of the field.

On the final turn, Johnston rolled into a 90° bank, and at only 50 feet (15 meters) above the ground, passed inside a Bell P-63 Kingcobra at 430 miles per hour (692 kilometers per hour) to win the race. His average speed for the ten laps was 373.908 mph (601.746 kilometers per hour).

After winning the 1946 Thompson Trophy Race, test pilot Tex Johnston kisses his wife, DeLores. (LIFE Magazine via Jet Pilot Overseas.)
Tex Johnston with the Thompson Trophy, 1946 National Air Races, Cleveland, Ohio. (LIFE Magazine)

Tony LeVier and his Lightning were in second place at 370.193 mph (595.768 kilometers per hour). Finishers 3, 4 and 5 were P-51D Mustangs. Number 6 was the lone FG-1D Corsair, followed by another P-51D. Proving that Woolams, Johnston and Stanley knew their airplane, the final three finishers were the three remaining P-63 Kingcobras.

An oil-streaked, race-winning Bell P-39Q Airacobra, NX92848, Tex Johnston’s Cobra II. The modified Allison engine’s undersized pistons allowed excessive blow-by. (San Diego Air and Space Museum Archives)

Cobra II competed in the 1947 Thompson Trophy Race. Flown by Bell Aircraft Corp. test pilot Gerald A. (“Jay”) Demming, and carrying the race number 11, it finished in third place behind two Goodyear F2G-1 Super Corsairs. Demming’s average speed was 367.625 miles per hour (591.635 kilometers per hour).

In the 1948 Thompson race, Cobra II, still carrying the number 11, was flown by Charles Brown. For this year, the race was twenty laps of a shorter, 15 mile (24.1 kilometer) course. Cobra II had qualified in first place with an average speed of 418.300 miles per hour (673.189 kilometers per hour). Brown led the race for 18 laps. His highest speed for a single lap was 413.907 miles per hour (666.119 kilometers per hour). He had to land, though, when the modified Allison engine began losing power. The race was won by a P-51D Mustang.

Bell P-39Q-10-BE Airacobra NX92849
Cobra II at the 1947 National Air Races, with race number 11. It was flown in the Thompson Trophy race by Bell test pilot Jay Demming, who placed third. (SDASM)

The history of Cobra II is elusive until it was purchased by Ed Maloney in 1960. It was sold to Michael D. Carroll in 1967. Carroll was the owner of Signal Trucking Co., and lived in Palos Verdes, California. The Airacobra was now registered N9824. Carroll had the airplane’s wings shortened by 4 feet per side (1.2 meters), and renamed it Cobra III.

On 10 August 1968, Carroll and Cobra III took of from Long Beach Airport (LGB), enroute to Orange County Airport (SNA), at nearby Santa Ana, California. At 11:15 a.m., the racer crashed at the Seal Beach Naval Weapons Station. Carroll bailed out, but his parachute did not open and he was killed. His body was located 125 feet (38 meters) from the wreckage. There was no post-crash fire. Lieutenant Commander Jack Kellicott, U.S. Navy, said that the airplane had run out of fuel.

Tex Johnston left Bell Aircraft Corporation and moved on to Boeing in Seattle, initially testing the swept-wing XB-47 Stratojet. He made the first flights of the YB-52 and XB-52 Stratofortress; the Model 367-80 (the “Dash 80”), which he notoriously rolled over Lake Washington, 6 August 1955; the KC-135A Stratotanker; and the Model 707 airliner. As Boeing’s Chief of Flight Test, Tex Johnston set the standard by which modern flight testing is carried out.

Alvin Melvin (“Tex”) Johnston, Chief of Flight Test. (The Boeing Company)

Highly recommended: Tex Johnston, Jet-Age Test Pilot, by A.M. “Tex” Johnston with Charles Barton, Smithsonian Books, Washington, D.C., 1991

© 2018, Bryan R. Swopes

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21 August 1944

Robert L. Hall in the cockpit of the prototype Grumman XF8F-1 Bearcat. (Northrop Grumman)

21 August 1944:¹ The first of two Grumman XF8F-1 Bearcat prototypes, Bu. No. 90460, made its first flight at Bethpage, New York, with Grumman’s Chief Engineer and test pilot Robert Leicester Hall at the controls. The Bearcat was a light-weight high performance interceptor, designed to operate from the U.S. Navy’s smaller aircraft carriers. It used an air-cooled, supercharged, 2,804.4-cubic-inch-displacement (45.956 liter) Pratt & Whitney Double Wasp 2SC13-G (R-2800-22) two-row, 18-cylinder radial engine, an uprated version of the engine used in its predecessor, the Grumman F6F Hellcat.

The R-2800-22 engine was rated at 1,700 horsepower at 2,600 r.p.m. at Sea Level, and 2,100 horsepower at 2,800 r.p.m., for takeoff and Military Power. In order to use the engine’s power more effectively, the prototype Bearcat used a 12-foot, 4-inch (3.759 meter) diameter, four-bladed Aero Products, Inc., propeller, driven through a 0.45:1 gear reduction.

Prototype Grumman XF8F-1 Bearcat. (Northrop Grumman)

The Bearcat was 20% lighter than the Hellcat. It was 50 miles per hour faster and had a much higher rate of climb.

For aircraft carrier operations, the new fighter could not sacrifice structural strength. In order to limit the weight, armament was reduced to four .50-caliber machine guns, and fuel capacity was also less than that of the Hellcat, giving it reduced range.

Grumman F8F-1 Bearcat with wings folded. (U.S. Navy)
Grumman F8F-1 Bearcat with wings folded, 20 March 1945. (Northrop Grumman)

The production F8F-1 Bearcat was 27 feet, 6 inches (8.382 meters) long with a wingspan of 35 feet, 6 inches (10.820 meters) and overall height of 13 feet, 10 inches (4.216 meters) (to tip of propeller, in three-point position). With its wings folded, the width of the Bearcat was reduced to 23 feet, 9½ inches (7.252 meters).

The Bearcat’s wings are sharply tapered. Their angle of incidence is −1½°, and there is 5° 30′ dihedral. The leading edges are swept aft 5° 5′. The chord decreases from 9 feet, 7.87 inches (2.943 meters) at the root to 4 feet, 3.5 inches (1.308 meters) at a point 6 inches (15.24 centimeters) inboard from the tip. The total wing area is 244 square feet (22.7 square meters).

The fighter’s horizontal stabilizer has a span of 15 feet, 9 inches (4.801 meters) and a total area of 52.2 square feet (4.85 square meters). Its angle of incidence is +½°. The rudder has a height of 6 feet, 1–13/16 inches (1.875 meters). The vertical tail has a total area of 20.8 square feet (1.93 square meters), and is offset 2° left.

The F8F-1’s empty weight was 7,070 pounds (3,207 kilograms) and maximum takeoff weight was 12,947 pounds (5,873 kilograms). The F8F-2’s empty weight increased to 7,650 pounds (3,470 kilograms), and its maximum takeoff weight was 13,460 pounds (6,105 kilograms).

Grumman XF8F-1 Bearcat prototype at NACA Langley Memorial Aeronautical Laboratory, Hampton, Virginia, 5 February 1945. (NASA)

The production F8F-1 was powered by a Pratt & Whitney Double Wasp 2SC14-G (R-2800-34W) engine which had the same Sea Level power ratings as the R-2800-22. It produced 1,500 horsepower at 2,600 r.p.m. at 18,500 feet (5,639 meters) and had a Military Power rating of 1,700 horsepower at 2,800 r.p.m. at 16,000 feet (4,877 meters). The gear reduction drive ratio was also 0.45:1. A slightly larger Aero Products propeller with a diameter of 12 feet, 7 inches (5.835 meters) was installed. The R-2800-34W was 6 feet, 2.134 inches (1.883 meters) long, 4 feet, 4.80 inches (1.341 meters) in diameter and weighed 2,358.5 pounds (1,069.8 kilograms).

The F8F-2 was powered by a Pratt & Whitney R-2800-30W. The Normal Power rating increased to 1,720 horsepower at 2,600 r.p.m. at Sea Level, and 1,450 horsepower at 22,000 feet (6,706 meters). Takeoff and Military Power also increased: 2,250 horsepower at 2,800 r.p.m. at Sea Level, and 1,600 horsepower at 22,000 feet (6,706 meters). The R-2800-30W also drove an Aero Products propeller. The gear reduction ratio was the same. Its dimensions were slightly different than the -34W: 7 feet, 8.75 inches (2.356 meters) long, and 4 feet, 5.00 inches (1.346 meters) in diameter. The engine’s weight increased to 2,560 pounds (1,161 kilograms).

Grumman F8F-1 Bearcat Bu. No. 90448 in the Full Scale Tunnel at NACA Langley Memorial Aeronautical Laboratory. (NASA EL-2003-00320)

The Bearcat had a top speed of 336 knots (387 miles per hour/622 kilometers per hour) at Sea Level, and 388 knots (447 miles per hour/719 kilometers per hour) at 28,000 feet (8,534 meters). The airplane had initial rate of climb at Sea Level of 4,465 feet per minute (22.68 meters per second) and it could climb to 20,000 feet (6,096 meters) in 8.4 minutes. Its ceiling was 38,200 feet (11,643 meters).

Fuel capacity is 185 U.S. gallons (700 liters). The fighter’s range could be extended with a jettisonable centerline and two underwing tanks. The Bearcat’s combat radius was 235 nautical miles (270 statute miles/435 kilometers). Its maximum range, with three external tanks (350 gallons/1,325 liters), was 1,595 nautical miles (1,835 statute miles/2,954 kilometers).

The F8F-1 Bearcat was armed with four Browning AN-M2 .50-caliber machine guns. Inboard guns were provided with 325 rounds of ammunition, each, while the outboard guns had 200 rounds per gun. The F8F-2 replaced these with four M3 20 mm autocannon. Each inboard cannon had 325 rounds per gun, and the outboard guns had 188 rounds each. The F8F could also be armed with up to three 11.75-inch (29.845 centimeters) Tiny Tim air-to-ground rockets, or four 5-inch (12.7 centimeter) High Velocity Aerial Rockets (HVAR). For bombing missions, the Bearcat could carry one 1,600 pound (726 kilograms) bomb on the centerline and two 1,000 pounders (454 kilograms, each) under the wings.

The first prototype Grumman XF8F-1 Bearcat, Bu. No. 90460, crashed into Chesapeake Bay during gunnery tests at NAS Patuxent River, Maryland, 18 March 1945. Its pilot was missing, presumably killed. The airplane has recently–probably—been located.²

“Multi-beam echo image of the aircraft at the bottom of the Chesapeake Bay believed to be the XF8F-1 Bearcat lost out of NAS Patuxent River March 18, 1945.” (NOAA/Naval Aviation News)

Between 1945 and 1949, Grumman produced 1,265 F8F Bearcats, including a civilian G-58A and a G-58B. A number of American test pilots and astronauts flew the Bearcat in naval service, and several, including Neil Armstong, described it as their all-time favorite airplane.

Grumman F8F bearcat fighters aboard the Essex-class aircraft carrier, USS Tarawa (CV-40) circa 1948. (U.S. Navy)
Grumman F8F Bearcat fighters ready for takeoff aboard the Essex-class aircraft carrier, USS Tarawa (CV-40) circa 1948. (U.S. Navy)

Robert Leicester Hall was born at Taunton, Massachussetts, 22 August 1905. He was the son of Bicknell Hall, a mechanical engineer, and Estella Beatrice Lane Hall.

Robert L. Hall (Michiganesian of 1927)

Hall attended the University of Michigan, graduating in 1927 with Bachelor of Science degree in Mechanical Engineering (B.S.M.E.). He was a member of the Phi Gamma Delta (ΦΓΔ) fraternity and the glee club. While at the University, Hall became a member of the American Society of Mechanical Engineers.

In 1929 he went to work for the Fairchild Airplane Manufacturing Company at Farmingdale, New York. While there, Hall met his first wife, Eugenie Therese Zeller, a 1928 graduate of Cornell University, and a secretary at the plant. They were married in 1930, and lived in a rented home on St. James Avenue, Chicopee City, Massachusetts. Their son, Robert Jr., was born 5 November 1931. They later divorced.

Granville Brothers Gee Bee Z

Also in 1931, Hall began working for Granville Brothers Aircraft at Springfield, Massachusetts. He designed the Gee Bee Model Z Super Sportster air racer. He left Granville Brothers in 1933 to go to work for the Stinson Aircraft Company in Dayton, Ohio. There he designed the Stinson Reliant.

Stinson Reliant (NASA)

In 1936, Bob Hall became the Chief Engineer for the Grumman Aircraft Engineering Corporation, Bethpage, Long Island, New York. He designed the F4F Wildcat, F6F Hellcat, F7F Tigercat, and F8F Bearcat fighters, and the TBF Avenger torpedo bomber. As corporate vice president, he supervised the design of the F9F Panther and Cougar jet fighters.

A U.S. Navy Grumman F4F-3 Wildcat in non-specular blue-gray over light-gray scheme in early 1942. (U.S. Navy)
Two Grumman F6F-3 Hellcat fighters, Summer 1943. (U.S. Navy)
Grumman F7F-3N Tigercat. (U.S. Navy)
Grumman TBF Avenger torpedo bomber. (U.S. Navy)
Ensign Neil A. Armstrong, as wingman to Lieutenant (j.g.) Ernie Moore, is flying the second Grumman F9F-2 Panther, Bu. No. 125122 (marked S 116), assigned to VF-51, USS Essex (CV-9), 1951. (Naval Aviation Museum)

Hall married his second wife, Rhoda C. Halvorsen, 18 January 1939, at New York City, New York.

Robert Hall retired from Grumman in 1970. Two of his sons, Eric and Ben Hall, founded Hall Spars and Rigging of Bristol, Rhode Island.

Robert Leicester Hall died at Newport, Rhode Island, 25 February 1991 at the age of 85 years.

¹ Some sources give 31 August 1944 as the date of the first flight.

² Naval Aviation News, 31 August 2017:

http://navalaviationnews.navylive.dodlive.mil/2017/08/31/lost-bearcat-found-or-still-missing/

© 2018, Bryan R. Swopes

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19 August 1940

Vance Breese (SDA&SM)

19 August 1940: At Mines Field (now known as Los Angeles International Airport), the first North American Aviation B-25 twin-engine medium bomber, serial number 40-2165, took off on its first flight with test pilot Vance Breese at the controls and engineer Roy Ferren in the co-pilot’s position.

The airplane, North American model NA-62, serial number 62-2834, was developed from two earlier designs which had been evaluated by the U.S. Air Corps but rejected, and it was ordered into production without a prototype being built.

The first few B-25s built—sources vary, but 8–10 airplanes—were built with a constant dihedral wing. Testing at Wright Field showed that the airplane had a slight tendency to “Dutch roll” so all B-25s after those were built with a “cranked” wing, with the outer wing panels having very slight dihedral ¹ and giving it the bomber’s characteristic “gull wing” appearance. The two vertical stabilizers were also increased in size.

40-2165 was retained by North American for testing while the next several aircraft were sent to Wright Field.

Roy Ferren (SDA&SM)

The B-25 was named Mitchell in honor of early air power advocate Brigadier General Billy Mitchell. A total of 9,984 B-25s, F-10 reconnaissance variants and U.S. Navy and Marine Corps PBJ-1 patrol bombers were built by North American Aviation at Inglewood, California and Kansas City, Kansas. The last one, a TB-25J, remained in service with the U.S. Air Force until 1960.

Twenty-three B-25s were built before the B-25A Mitchell went into production. The B-25 was operated by a crew of five. It was 54 feet, 1 inch (16.485 meters) long with a wingspan of 67 feet, 6.7 inches (20.592 meters) and overall height of 16 feet, 4 inches (4.978 meters). The empty weight was 17,258 pounds (7,828 kilograms) and the maximum gross weight was 28,557 pounds (12,953 kilograms).

Scale model of a North American Aviation B-25 medium bomber being tested in a wind tunnel. (4″ × 5″ Kodachrome transparency by Alfred Palmer)

The B-25 was powered by two air-cooled, supercharged, 2,603.737-cubic-inch-displacement (42.688 liter) Wright Aeronautical Division Cyclone 14 GR2600B665 (R-2600-9) two-row 14-cylinder radial engines which were rated at 1,500 horsepower at 2,400 r.p.m., and 1,700 horsepower at 2,600 r.p.m. for takeoff. These engines (also commonly called “Twin Cyclone”) drove three-bladed Hamilton Standard Hydromatic variable-pitch propellers through 16:9 gear reduction. The R-2600-9 was 5 feet, 3.1 inches (1.603 meters) long and 4 feet, 6.26 inches (1.378 meters) in diameter. It weighed 1,980 pounds (898 kilograms).

The medium bomber had a maximum speed of 322 miles per hour (518 kilometers per hour) at 15,000 feet (4,572 meters) and a service ceiling of 30,000 feet (9,144 meters). It could carry a 3,000 pound bomb load 2,000 miles (3,219 kilometers).

Defensive armament consisted of three air-cooled Browning M2 .30-caliber aircraft machine guns and one Browning AN-M2 .50-caliber machine gun.

After testing was completed, B-25 40-2165 was retained by North American and modified as a company transport. On 8 January 1945, flown by Edgar A. Stewart, the airplane suffered an engine failure and made a forced landing at Mines Field—the location of its first flight. The prototype B-25 was damaged beyond repair.

Front view of the first North American B-25 Mitchell, 40-2165. The constant dihedral wing was used on the first nine airplanes built. (U.S. Air Force)
Front view of the first North American Aviation B-25 Mitchell medium bomber, 40-2165, at Mines Field, August 1940. The constant dihedral wing was used on the first nine airplanes built. (U.S. Air Force)
North American Aviation NA-62, B-25 Mitchell 40-2165, left front. (U.S. Air Force)
North American B-25 Mitchell 40-2165, left rear. (U.S. Air Force)
North American Aviation B-25 Mitchell 40-2165, left rear. (U.S. Air Force)
North American Aviation B-25A Mitchell medium bomber of the 34th Bombardment Squadron (Medium), 17th Bombardment Group (Medium), based at McChord Field, south of Tacoma, Washington, and Pendleton Army Airfiled, northwest of Pendleton, Oregon, circa 1941. (U.S. Air Force)
North American Aviation B-25A Mitchell medium bomber of the 34th Bombardment Squadron (Medium), 17th Bombardment Group (Medium), based at McChord Field, south of Tacoma, Washington, circa 1941. (U.S. Army Air Corps 10822 AC)

¹ The wing center section of the B-25H and B-25J has 4° 38′ 23″ dihedral. The outer sections have 0° 21′ 39″. The wing has 2° 29′ 37″ negative twist.

© 2019, Bryan R. Swopes

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