Grumman Tarpon I (TBF-1 Avenger)

During the late 1930s the U.S. Navy began to modernize its fleet of carrier aircraft. By the end of the decade, all metal monoplane fighters, dive bombers and torpedo bombers were in service. In addition, advanced fighters and dive-bombers were in the testing stage. Torpedo bomber development, however, had not kept pace and the Douglas TBD-1 Devastator, which entered service in 1937, still equipped the Torpedo Bomber (VT) squadrons. The Navy realized that further development could not overcome the Devastator's lack of speed and range, and in 1939, the Bureau of Aeronautics issued a design specification for a new carrier-based torpedo bomber. Both the Vought and the Grumman companies submitted designs to fulfil the specification.

Grumman's design was designated the XTBF-1. It bore a family resemblance to the company's successful Wildcat fighter. Besides a general similarity in appearance, the new torpedo bomber used the same rearward-folding wings as did its smaller cousin. This allowed the large TBFs to be packed tightly together and to fit on deck elevators, increasing the number that could operate from carriers. The Grumman torpedo bomber could even operate from the small escort carriers, whose size prohibited their carrying many other large aircraft.

During the late 1930s the U.S. Navy began to modernize its fleet of carrier aircraft. By the end of the decade, all metal monoplane fighters, dive bombers and torpedo bombers were in service. In addition, advanced fighters and dive-bombers were in the testing stage. Torpedo bomber development, however, had not kept pace and the Douglas TBD-1 Devastator, which entered service in 1937, still equipped the Torpedo Bomber (VT) squadrons. The Navy realized that further development could not overcome the Devastator's lack of speed and range, and in 1939, the Bureau of Aeronautics issued a design specification for a new carrier-based torpedo bomber. Both the Vought and the Grumman companies submitted designs to fulfil the specification.

Grumman's design was designated the XTBF-1. It bore a family resemblance to the company's successful Wildcat fighter. Besides a general similarity in appearance, the new torpedo bomber used the same rearward-folding wings as did its smaller cousin. This allowed the large TBFs to be packed tightly together and to fit on deck elevators, increasing the number that could operate from carriers. The Grumman torpedo bomber could even operate from the small escort carriers, whose size prohibited their carrying many other large aircraft.

Another innovation was the electrically-powered turret in the rear gunner's station. Manufacturers had tried putting a turret in this position before, but the manual or hydraulic turrets of the time were too slow and unreliable. This was the case with Curtiss's SB2C Helldiver dive-bomber, which never did find a suitable turret. Grumman, however, decided to design its own and hit upon the idea of using fast and reliable electric motors. The turret carried only one gun to save weight, but it was a .50 caliber weapon, which was more effective than the two .30 caliber guns carried by many other aircraft. A .30 caliber gun was included in the radioman's compartment, positioned to fire down and to the rear of the aircraft, in addition to a forward-firing .30 caliber gun in the engine cowling.

The Grumman TBF-1 was lighter, faster, and had more range than the Vought entry, however, one of the main reasons for the selection of the TBF was the ability of Grumman to produce the airplanes. Vought was involved with the development of the Corsair and was not able to devote the time to the project. On December 23, 1941, just two weeks after the attack on Pearl Harbor, Grumman received an order for 286 TBFs. While some believe that the December 7 attack inspired the plane's name, the Navy gave its new torpedo bomber the name "Avenger" earlier in October 1941 when it assigned names to its aircraft in addition to the standard letter-number designations.

The combat debut of the Avenger at the Battle of Midway, however, turned out to be a disaster. The events leading up to the battle began with the delivery of the first operational TBFs to a detachment from VT-8 at Norfolk, Virginia. The aircrews were left behind to bring the first TBFs up to operational status while the carrier Hornet proceeded to Hawaii. When the crews and planes were ready, they were shipped to Pearl Harbor with the intention of joining the Hornet for the upcoming battle. But the Avengers just missed the carrier, which had sailed the day before to head off the Japanese attack on Midway. Shortly after the detachment's arrival, the aircrews learned that volunteers were needed to fly six Avengers out to Midway Island. Many of the volunteers had never flown out of sight of land before, but all the aircraft made it to Midway. On June 4, 1942, these six TBFs took off from the island and, along with 27 Marine dive bombers and four Army B-26s, attacked the Japanese armada. This attack, along with one by TBDs a few hours later, was turned back with heavy losses. Of the six Avengers that took off from Midway, only one would return to the island, badly shot up, with two crewmembers wounded and one dead. The sacrifice of the torpedo bombers, however, was not in vain. The failed attack had disrupted the Japanese operational schedule, and it was this delay that resulted in the Japanese planes being present on the carrier decks - fully fueled and armed - when three squadrons of SBD Dauntless dive bombers arrived a few hours later. In the ensuing battle, three of the four Japanese carriers were sunk within the first five minutes, and the fourth was sunk later that day.

Despite the victory, the Japanese had mauled the torpedo squadrons at the Battle of Midway. Besides the Avengers, many of the older Devastators had been lost. Meeting this increased need for TBFs was becoming increasingly difficult for Grumman (which was producing the Wildcat and tooling up to build the Hellcat) to fulfill. Earlier that year, however, Grumman officials met with representatives of General Motors (GM). The auto industry had been put on hold when the war started and GM was looking for work building spare parts for an aircraft manufacturer. The auto executives were surprised to find that Grumman was looking for someone to build complete Avengers. A deal was struck and GM's Eastern Aircraft Division began to produce Avengers under the designation TBM-1. In December 1943, Grumman would cease to produce the TBF and Eastern Aircraft would, by war's end, produce three-quarters of all Avengers built.

One of the problems with the TBF/TBM-1 was the lack of forward firepower. The single .30 caliber gun in the cowling was inadequate. In 1943, this gun was eliminated and a .50 caliber gun was installed in each wing. This model was then designated the TBF/TBM-1C. The seat and instruments, which were located behind the pilot's seat, were replaced with electronic equipment.

The last major modification of the Avenger was the TBM-3. The installation of a more powerful engine was the most prominent feature of this model. The Avenger had always been slightly underpowered and the new engine was an attempt to correct this deficiency. The TBM-3 was the most numerous of the variants produced.

The Avenger is most often thought of as a torpedo bomber, but because of the unreliability of American torpedoes and the danger of this type of attack, it was more often equipped as a bomber. Later variants would be used as night fighters, radar-equipped submarine hunters, specialized submarine attack aircraft, and electronic countermeasures aircraft. They even became the first aircraft to be specifically modified to carry personnel and equipment to and from the carrier. Being one of the largest carrier aircraft, the Avenger was a natural for the role of what the Navy would call carrier onboard delivery (COD).

Many other countries also used Avengers. The British were the first to receive them under Lend-Lease. They made several modifications to the aircraft which, until 1944, was designated the Tarpon. The most noticeable modifications made by the British were the bulged windows fitted to the radioman's station on the sides of the aircraft. The British also kept a navigator's position behind the pilot on all their Avengers. New Zealand, Canada, France, and the Netherlands also operated Avengers in the post-war period. Even Japan used the aircraft, which had played a large part in its defeat, until the early 1960s.

The Avenger's successful military career is only part of the story. After the war, many surplus Avengers were used successfully as aerial firefighting aircraft. Many of these were still in use more than 30 years after their wartime service.

While the Avenger suffered from a lack of speed and performance, it had many positive qualities. It was a large aircraft that could accommodate many different payloads. It had the range to fly as far, or farther, than its escorting fighters. And most important, it was a safe plane to fly and it had pleasant flight characteristics. These qualities would serve the Avenger well in both war and peace.

The National Air & Space Museum's aircraft, Bureau of Aeronautics Number (BuNo) 24085, was constructed as a TBF-1 and was part of the fourth batch of TBFs manufactured. The aircraft was one of the first 200 Avengers delivered to the British, who called them Tarpons, and was assigned the number FN 859. The museum's Tarpon was delivered to the British at Quonset Point, Rhode Island, on June 8, 1943. The standard British modifications were probably carried out at this time.

The subsequent wartime history of BuNo 24085 is somewhat vague because of a lack of documentation in both the U.S. and Britain. We know that the aircraft served with No.738 Squadron of the Royal Navy Fleet Air Arm, and it moved with this squadron to Lewiston, Maine, on July 31, 1943. No 738 was a training squadron and the museum's aircraft appears to have served in that role throughout the war. Besides mention of a landing accident in October 1943, however, there is no further information on its wartime service.

No. 738 Squadron was disbanded in July 1945 and BuNo 24085 was accepted by the U.S. Navy at Norfolk Naval Air Station on July 2, 1945. After being assigned to the general aircraft pool at Norfolk, the museum's aircraft was moved to Patuxent River NAS for service tests in December. A year later, in November 1946, BuNo 24085 was stricken from the list of active aircraft. From that time, until the museum acquired the aircraft in 1960, nothing is known. The aircraft probably served as a "gate guardian" during this period.

The physical evidence of BuNo 24085 leaves as many unanswered questions as the written record. The data plate lists the aircraft as a TBF-1 and it bears the bulged observer windows, which are the most obvious mark of the British modifications. The British roundels can also be seen under the U.S. markings. The mounts for the early .30 caliber nose gun are present but the weapon is missing and the gun trough in the cowling has been faired over. The aircraft also has the radio equipment in the station behind the pilot, which was a feature of the TBM-1C. The British, on the other hand, kept a navigator position, even on the later models.

One of the biggest mysteries is what happened to the aircraft's wings. The wings, from the folding joint outwards, are from two separate aircraft. The port wing is from a TBM-1C with the mounts for the .50 cal. machine guns still present, even though the position has been faired over. The starboard wing is from a TBM-3J model. The yellow paint and squadron code showing through the topcoat of blue, identify this as a wing from an Avenger used as a utility aircraft. Detail differences, such as antennas, also differ between the two wings. Whether these wings were added in squadron use, as part of the service test at Patuxent River, or simply to make a complete aircraft for gate guardian duties is not known at this time.