The TBF/TBM Avenger

Once accepted by the Navy, Grumman built 2,291 TBFs before General Motors, Eastern Aircraft Division, began building them under license from Grumman. The US Navy nomenclature designated these identical aircraft as TBMs with GM building 7,546 for a type total of 9,837. (TBF = Grumman-built, and TBM = GM built)

Early models of both the TBF and TBM had Wright "Twin Cyclone" R-2600-8 engines developing only 1700 hp. Later production saw increases in power up to 1900 hp with the R-2600-20 engine. This engine was also used on the Boeing 314 Clipper flying boat, B-25 Mitchell, and some models of the A-20 Havoc. TBM-3s, with nearly 4,000 being built, had the more powerful engines. This required more cooling, the oil cooler was moved to the lower engine cowl lip and four more cowl flaps were added to each side. These changes and the removal of the 30 caliber ventral "stinger" gun are the primary visual differences between early and later model Avengers.

TBM-3 specifications

Dimensions:	Wing span 52'2", Length 40'0' (Width with wings folded: 16 ft)
Height:	16 ft 5 inches
Empty Weight:	10,843 lbs
Max Gross Weight:	18,250 lbs
Power:	Wright "Twin Cyclone" R-2600-20 engine 14 cylinders in two banks of 7, giving 1900 hp
Max Speed:	267 mph at 16,000 ft.
Ceiling:	23,400 ft
Range:	1,130 miles ( 2,265 miles with aux. fuel tank.)
Fuel:	325 US gallons. (90 ea wing, plus 145 fuselage tank)
Oil:	32 US gallons
Crew:	3 - Pilot, Gunner, plus Radioman in fuselage station

Armed and Radar Equipped

The TBF/TBM could carry one 2,000 lb torpedo; four 500 lb bombs or depth charges, twenty 100 lb bombs, mines or an auxiliary fuel tank of 275 gallons in the bomb bay. Combined wing stations carried either two 100 gallon droppable fuel tanks or two bombs of up to 1000 lb each depending on the mission. With a "useful load" of nearly 8,000 lbs of fuel and armament provided a wide range of missions - and the Avenger was outstanding in all.

At first the Grumman TBF-1 had a .30 cal gun mounted on the cowl, a 30 cal ventral gun (stinger) and the .50 cal gun in the powered turret. The turret is electrically powered, and traverses more that 180 degrees side-to-side, as well as elevation, with cam following safety switches to inhibit shooting off its own tail surfaces. By June of 1943 the -3E version had the single cowl gun replaced by two .50 cal guns in the wings and the ventral "stinger" machine gun was removed. The rudimentary but effective ASB radar with dual, aimable Yagi antennas was replaced the more advanced APS-4 radar with a single antenna mounted within a pod on the right wing. This increased the surface ship detection from approximately 40 miles to over 300. Internal armoring was also reduced by almost 250 lbs while power and gross weight were increased in these, the most common Avenger models.

The Avenger was the first US aircraft to be fitted with rockets used for ground attack. These were 5-inch HVAR variety with four mounted on each wing. The first use of the aerial rockets were to sink a U-boat on January 11, 1944.

The first torpedoes were the unreliable Mark 13 models which required to be dropped "low and slow" by the brave pilot who is most likely attacking a well-armed ship. In 1943 the reliable Mark 13-IA (ringtail) torpedo was deployed and could be dropped from a speed of up to 280 mph and 800 ft. Various techniques were used by different squadrons with accurate altitude often provided by a the Avenger's radar altimeter - separate from the search radar.

Bombs were also dropped by the pilot, either in a cluster or, using the "intervalometer" (set by the radioman) in a four-bomb stick. The pilot usually entered a 30 to 45 degree dive to about 500 ft elevation before releasing the bombs. A four-bomb stick, spaced 60 to 75 ft apart was used on maneuvering ships.

The "Middle Seat" Question

There was only one set of controls on the aircraft, and no access to the pilot's position from the rest of the aircraft. The original vacuum tube radio equipment was massive, especially by today's standards, and it filled the whole glass canopy to the rear of the pilot and ahead of the gun turret. These radios were accessible for adjustment and repair through a "tunnel" within the fuselage radioman's position. In addition, the Avenger was extensively equipped with search radar and communications on all bands from low frequency through VHF allowing it to become the early warning "eyes" for the fleet. The radio operator was always kept busy.

Our aircraft has been modified to provide an additional rear-mounted seat in place of the radios, which increases our crew compliment to four.

This is one of the first TBFs built and is likely one of those assigned to VT-8 squadron lost during the Battle of Midway. It shows the original four man crew which was later reduced by eliminating the horizontal bombardier behind the pilot. This area was quickly filled with communications radios, radar altimeter, IFF (Identification-Friend or Foe transponder) and a hydraulically operated autopilot as the TBF/TBM was continually upgraded with more modern equipment.

 

TBF/TBM Avenger In Battle

In the Atlantic theater, Avengers were launched from 14 smaller escort carriers (CVE) on anti-submarine roles. This was often done in pairs. One Avenger would be used as the "hunter" and carry additional fuel and droppable sonar-bouys to find submarines in the critical mid-Atlantic area beyond the reach of land-based bombers. When enemy subs were sighted, another "killer" Avenger would be bought in armed with depth charges and rockets. The 1160 lb, Mk 34 acoustic-homing anti-submarine torpedo called "Fido" was also successfully used in the Atlantic. The first submarine kill by Avengers was U-569 on May 22, 1943 with 53 final kills and one capture during WWII.

Although only 12 Japanese submarines were credited to the Avenger, both of the world's largest battleships - the Mushai and the Yamato - were sunk by Avenger bombs and torpedoes in the Pacific. The final Pacific score showed that Avengers accounted for 6 of the 10 Japanese battleships, 11 of the 15 carriers, and 10 of 14 heavy cruisers lost. Of the 12 remaining large Japanese ships, submarines sank eight and surface ships sank four. None were lost to horizontal bombing by Army planes.

The Marine Corps began land-based operations with TBF-1s at Guadalcanal in November 1942. The first Marine attack squadrons in combat in the Pacific had begun as SBD units, but by 1945, 23 Marine squadrons, land-based or on four escort carriers, used Avengers. These were used primarily for ground attack and tactical support.

Due to its weight, the Avenger was certainly not as nimble as the lighter Japanese Zeros and other enemy fighters. Therefore the best air-to-air combat tactic was to dive at a target aircraft, shoot, and continue the dive away. However the Avenger could absorb a lot of punishment and was well loved by those crew members that managed to limp home with battle damage. There are records of when the enemy had expended all of its ammo and simply had to leave. In spite of its shortcomings as a fighter, 98 aerial kills were recorded by Avenger air crews, and only 20 were lost in aerial combat from 1943 until the war's end. Other WWII aircraft designed by Grumman proved just as rugged, earning them the affectionate title of the "Grumman Iron Works".

Towards the end of WWII saw the development of the TBM-3W, the Navy’s first Airborne Early Warning (AEW) aircraft. Developed under Project Cadillac, it had a large APS-20 radar antenna underneath the fuselage that could detect enemy aircraft far beyond the line-of-sight of surface vessels. A circular area 200 miles in every direction could be scanned from 20,000 feet and relayed to ships. All armament had to be removed to accommodate the electronics and its operator, located with his console within the fuselage, and the XTBM-3W first flew on August 5, 1944. The extra fuel tanks were usually carried in this long-range "hunter" role with missions lasting up to 10-12 hours. In March 1945, deliveries began on the first 27 being rebuilt at the Johnsville Navy facility, and trials were made on the Ranger in May 1945. Four-plane TBM-3W units were first deployed with AEW installations on the Enterprise, Hornet, and Bunker Hill, late in 1945.

The last 24 Avengers were delivered to the Navy in August 1945.

The Final WWII Score

According to the USN statistics below, the Avenger single engined bomber bore the brunt with most bombs delivered (32,700 tons), and ships sunk. They accounted for 98 enemy aircraft destroyed while suffering only 47 losses in air-to-air combat. Note that this was against much nimbler and more heavily armed fighters! Of the 729 total Avenger losses, 422 came from anti-aircraft fire simply due to their tough and dangerous low-level mission - dropping bombs, launching rockets, depth charges, and torpedoes. The other "Operations" losses account for very bad landings, flying into the ground, fuel starvation, and other non-shellfire induces losses. With nearly 10,000 aircraft delivered, and over 46,000 combat sorties flown, the Avenger may be considered one of the safer places to be. Remember that "Fighters make movies - bombers make history"

		Total Action Sorties	TBF/TBM Losses					Enemy Aircraft Destroyed in Combat		Tons of Bombs Dropped
WWII Totals			On Action Sorties			Other Flights	On Ship or Gnd
			A/A	A/C	Ops			Bombers	Fighters
Carrier - USN		35,564	348	27	231	339	227	22	50	24,245
Carrier - USMC		496	5	0	0	1	0	0	0	304
Land-based - USN		3,290	16	9	15	20	3	0	7	2,701
Land-based - USMC		7,151	53	11	14	56	16	1	18	5,437
Other		137	0	0	0	0	0	0	0	50
Totals		46,638	422	47	260	416	246	23	75	32,737
			729	Combined				98	Combined
Carrier - CV		18,254	199	21	147	127	109	13	38	13,461
Carrier - CVL		6,379	72	4	40	85	57	4	6	4,831
Carrier - CVE, USN		10,931	77	2	44	127	61	5	6	5,953
Carrier - CVE, USMC		496	5	0	0	1	0	0	0	304
Aerial Combat		Sorties	Enemy A/C Engaged		Enemy A/C Destroyed		TBM/TBF Casualties		Enemy A/C Destroyed per each TBM/TBF Loss
Total War			Bombers	Fighters	Bombers	Fighters	Lost	Damaged
Carrier based		429	60	458	22	50	27	46	2.7
Land Based		94	2	142	1	25	20	34	1.3
Totals		523	62	600	23	75	47	80
		523	662	Combined	98	Combined	47		2.1	Total War
For the Year 1942		16	1	32	1	4	7	2	0.7	This Year
1943		56	12	62	8	7	8	18	1.9	"
1944		284	34	266	7	31	7	21	5.4	"
1945		73	13	98	6	8	5	5	2.8	"
Source: www.history.navy.mil/download/nasc.pdf

Continuing Use Post-war

After the war, the Navy’s carrier-based Avengers had no foreign surface fleets to oppose, and the attack forces shrunk. Submarines remained the only potential naval threat, so some Avengers were modified to the TBM-3S configuration, whose turret was removed.

Airborne early warning became a top priority, and by June 1948, the first AEW squadron, VC-2, was formed with TBM-3Ws, as additional conversions were made until 156 were in the fleet by 1953. Radar countermeasures were tested by TBM-3Q version. The last TBM-3E left squadron (VS-27) service in October 1954, but many Avengers also filled utility and non-combat roles.

When the Mutual Defense Assistance Program (MDAP) was established, second-hand TBM-3s of various modifications were sent to allied powers, with 117 sent to Canada in 1950 (including ours), 19 to Uruguay in 1949/50, and 140 to France, beginning in May 1951. Shipments of 100 TBM-3Es began in March 1953 for the Royal Navy, where they served ASW squadrons as Avenger AS.4, AS.5, or ECM.6, depending on what electronics was fitted. After their replacement by the Fairey Gannet in 1955, 47 were passed to France, and another 19 to the Netherlands were added to 58 acquired earlier from the United States.

In an ironic twist, 20 Avengers became the first combat planes of the new Japanese Navy (called the Maritime Self-Defense Force) in 1954/55. These became the last TBMs remaining in military service until retirement in 1962, but civilian Avengers (including ours) worked as forest firefighters in North America for many years afterwards.

Click the Our Own Avenger's History tab at left for more information.