From Joe Baugher:
Douglas A-26B Invader
The A-26B was the solid-nosed attack version of the Invader. The XA-26B-DE (41-19588) was the prototype of this particular version and was fitted with an unglazed nose housing a forward-firing 75-mm cannon. The crew consisted of pilot and gun loader/navigator seated side-by-side in the forward cockpit, and a gunner in the rear position behind the wing trailing edge. In addition, there was a “jump” seat behind the loader/navigator’s position that could be used by an extra person who was going along for a ride. The rear gunner was provided with two viewing windows, one in the dorsal position and the other in the ventral position, and he aimed the guns remotely via an optical sighting system.
It turned out that the XA-26B was the last Invader to be built at the El Segundo plant. Plans were for the production version of the Invader to be built at newly-constructed Douglas plants in Tulsa, Oklahoma and in Long Beach, California. It was planned that the solid-nosed B would be manufactured side-by side with the transparent-nosed C at both plants.
The production of the Invader began first at the Long Beach plant. The solid-nosed B was actually the first off the production line. The first of five A-26B-1-DL Invaders appeared in September of 1943. As compared with the prototype, the A-26B had an increased bomb load (6000 pounds) and higher internal fuel capacity of 1600 US gallons. The powerplants were housed in slightly revised nacelles and drove three-bladed propellers without spinners. The engines were a pair of 2000 hp Pratt & Whitney R-2800-27 radials.
Fifteen A-26B-5s followed with minor changes and which eliminated the camouflage that had been previously applied to bombers. These versions had one 75-mm cannon in the nose and two 0.50-inch machine guns on the left side.
A new all-purpose nose was installed beginning with the A-26B-10-DL. Initially, the USAAF was undecided about exactly what armament this version should carry. As originally planned, it was expected that the A-26B would be fitted with a variety of alternate solid nose sections, and that one deemed to the best would be selected. Options that were tested on early A-26Bs included one 75-mm cannon to starboard and two 0.50-inch machine guns to port, one 75-mm cannon to starboard and one 37-mm cannon to port, 2 37-mm cannon with one on each side of the nose, or one 37 mm cannon to starboard and two 0.50-inch machine guns to port; four 0.50-inch guns starboard and one 37-mm cannon to port; or four 0.50-inch guns to starboard and two 0.50-in guns to port. Eventually at the end of 1944, the USAAF finally made up its mind and decided that the solid-nosed A-26B would have six machine guns. with 400 rounds per gun. The guns in the two turrets had 500 rounds each.
Beginning with the A-26B-15, the forward-firing armament could be supplemented by eight 0.50-inch guns mounted in four twin packages underneath the outer wing panels.
Five aircraft from the initial Fiscal Year 1941 A-26 production batch were completed as A-26C-DL bombers with transparent noses and two nose guns. These were destined to be the only A-26Cs to be built at Long Beach, all the remaining A-26Cs being built at Tulsa.
The first 500 Invaders (up to A-26B-40-DL) were built at Long Beach. A parallel production line was established at Tulsa, Oklahoma for 500 aircraft ordered on March 17, 1943. The first Tulsa-built A-26Bs appeared in January of 1944. Of the Tulsa-built Invaders, 205 were delivered as A-26Bs with the rest being built as A-26Cs with glazed noses. Most of these Tulsa-built A-26Bs were powered by the Ford-built R-2800-71 engine with a revised ignition system.
Although both the Long Beach and Tulsa plants had started building both Invader versions, it was decided in late 1944 that this was an inefficient arrangement and that it would make better sense for the Long Beach plant to build only A-26Bs and the Tulsa plant to build only A-26Cs. This was indeed done, and the Long Beach plant stopped producing A-26Cs after only five were built.
During production, a number of improvements were introduced on the line. The oil cooler inlets on the wing leading edge were redesigned. The dorsal turret was modified to eliminate empennage buffeting. Initial combat reports from the field had complained about poor visibility from the cockpit, especially to the side. In order to improve visibility, the original flat-topped cockpit canopy which opened upward on the right side of the cockpit was replaced by a raised canopy opening in clamshell-fashion in two separate frameless transparent elements hinged at the sides of the fuselage. The canopy was a bit narrower on the pilot’s side of the aircraft than it was on the copilot’s. The new canopy enabled the pilot to see over both engine nacelles and towards the tail surfaces and it made it possible for him to check whether both main landing wheels were down. This new canopy was at first hand-built and fitted to a few early aircraft, but was introduced as standard equipment beginning with the A-26B-30-DL block.
Beginning with the A-26B-45-DL block, the engines were switched to Ford-built R-2800-79 with water injection, raising the war emergency power to 2350 hp.
The forward-firing armament of the early A-26B was found to be insufficient, especially in the Pacific theatre. Beginning with the A-26B-50-DL production block, a new eight-gun nose was fitted, and six internally-mounted 0.50-inch guns were mounted in the outer wing panels so that bombs or rockets could be carried underneath the wings. However, the eight-gun nose and the internal wing guns were often retrofitted to earlier A-26B versions, so the mere presence of these features cannot be used as a positive identification feature.
In aircraft destined for service in the Pacific (-51-DL, -56-DL, -61-DL, and -66-DL), the remotely-controlled ventral turret was replaced by a 125-US gallon auxiliary tank for extra range.
A total of 1150 A-26Bs were built at Long Beach (A-26B-1-DL to A-26B-66-DL) and an additional 205 were built at Tulsa (A-26B-5-DT to A-26B-25-DT). Production of the A-26B ended at Long Beach in September 1945, when the end of the war resulted in the cancellation of further contracts. Production of the B at Tulsa had ceased at the end of 1944 at Tulsa, when the decision was made that the Oklahoma plant would concentrate solely on the transparent-nosed A-26C version.
In June of 1948, the A-26B was re-designated B-26B. There was no danger of confusion with the Martin B-26 Marauder, since that aircraft was by that time out of service.
A lot of people have asked how the crew got in and out of the plane. Here’s how ex-Invader pilot Bob McFarland describes it. There was a spring-loaded one-rung ladder on the right side of the fuselage just in front of the wing. On the side of the fuselage there were a series of spring-loaded covered slots for feet and hands. The entering crewman would pull down the ladder and use the slots to crawl up the side of the plane to the top of the fuselage. Once on top, the entrance to the cockpit was made through the open clamshell doors. By all accounts, the entry into the cockpit was tricky and took a bit of getting used to. Once inside the cockpit, the fastening of the canopy was a difficult operation, and there were occasions when it wasn’t fastened properly and flew open in flight. The rear gunner crawled up the side of the aircraft in the the same way the pilot and navigator did, but once on top of the fuselage he would have to crawl to the rear and wend his way over the dorsal turret, open a hatch in the transparent upper cover and enter his compartment.
If it became necessary to bail out in the event of an inflight emergency, both of the clamshell canopy doors would be jettisoned and the pilot and navigator would crawl out on the right side of the aircraft and exit over the wing (the leading edge of the wing was just aft of the rear of the clamshell door) and hope that they weren’t hit by the horizontal stabilizer. The pilot went out the right side as well, since it was difficult for him to exit on the left, because the clamshell door was considerably shorter on that side and stopped well short of the leading edge of the wing. The gunner would exit the aircraft via the same hatch he used to enter.
Serials of A-26B:
41-19588 Douglas XA-26B-DE Invader c/n 1006 41-39100/39104 Douglas A-26B-1-DL Invader c/n 6813/6817 41-39105/39119 Douglas A-26B-5-DL Invader c/n 6818/6832 41-39120/39139 Douglas A-26B-10-DL Invader c/n 6833/6852 41-39140/39151 Douglas A-26B-15-DL Invader c/n 6853/6864 41-39153/39192 Douglas A-26B-15-DL Invader c/n 6866/6905 41-39194 Douglas A-26B-15-DL Invader c/n 6907 41-39196/39198 Douglas A-26B-15-DL Invader c/n 6909/6911 41-39201/39299 Douglas A-26B-20-DL Invader c/n 6914/7012 41-39300/39349 Douglas A-26B-25-DL Invader c/n 7013/7062 41-39350/39424 Douglas A-26B-30-DL Invader c/n 7063/7137 41-39425/39499 Douglas A-26B-35-DL Invader c/n 7138/7212 41-39500/39599 Douglas A-26B-40-DL Invader c/n 7213/7312 43-22252/22266 Douglas A-26B-5-DT Invader c/n 18399/18413 43-22267/22301 Douglas A-26B-10-DT Invader c/n 18414/18448 43-22302/22303 Douglas A-26B-16-DT Invader c/n 18449/18450 43-22305/22307 Douglas A-26B-15-DT Invader c/n 18452/18454 43-22313/22345 Douglas A-26B-15-DT Invader c/n 18460/18492 43-22350/22399 Douglas A-26B-15-DT Invader c/n 18497/18546 43-22400/22453 Douglas A-26B-20-DT Invader c/n 18457/18600 43-22454/22466 Douglas A-26B-25-DT Invader c/n 18601/18613 44-34098/34217 Douglas A-26B-45-DL Invader c/n 27377/27496 44-34218/34286 Douglas A-26B-50-DL Invader c/n 27497/27565 44-34287 Douglas A-26B-51-DL Invader c/n 27566 44-34288/34296 Douglas A-26B-50-DL Invader c/n 27567/27575 44-34297/34298 Douglas A-26B-51-DL Invader c/n 27576/27577 44-34299/34322 Douglas A-26B-50-DL Invader c/n 27578/27601 44-34323 Douglas A-26B-51-DL Invader c/n 27602 44-34324/34326 Douglas A-26B-50-DL Invader c/n 27603/27605 44-34327 Douglas A-26B-51-DL Invader c/n 27606 44-34328/34330 Douglas A-26B-50-DL Invader c/n 27607/27609 44-34331 Douglas A-26B-51-DL Invader c/n 27610 44-34332 Douglas A-26B-50-DL Invader c/n 27611 44-34333/34334 Douglas A-26B-55-DL Invader c/n 27612/27613 44-34335 Douglas A-26B-56-DL Invader c/n 27614 44-34336/34338 Douglas A-26B-55-DL Invader c/n 27615/27617 44-34339 Douglas A-26B-56-DL Invader c/n 27618 44-34340/34342 Douglas A-26B-55-DL Invader c/n 27619/27621 44-34343 Douglas A-26B-56-DL Invader c/n 27622 44-34344/34346 Douglas A-26B-55-DL Invader c/n 27623/27625 44-34347 Douglas A-26B-56-DL Invader c/n 27626 44-34348/34350 Douglas A-26B-55-DL Invader c/n 27627/27629 44-34351 Douglas A-26B-56-DL Invader c/n 27630 44-34352/34363 Douglas A-26B-55-DL Invader c/n 27631/27642 44-34364 Douglas A-26B-56-DL Invader c/n 27643 44-34365/34367 Douglas A-26B-55-DL Invader c/n 27644/27646 44-34368 Douglas A-26B-56-DL Invader c/n 27647 44-34369/34371 Douglas A-26B-55-DL Invader c/n 27648/27650 44-34372 Douglas A-26B-56-DL Invader c/n 27651 44-34373/34376 Douglas A-26B-55-DL Invader c/n 27652/27655 44-34377 Douglas A-26B-56-DL Invader c/n 27656 44-34378/34381 Douglas A-26B-55-DL Invader c/n 27657/27660 44-34382 Douglas A-26B-56-DL Invader c/n 27661 44-34383/34386 Douglas A-26B-55-DL Invader c/n 27662/27665 44-34387 Douglas A-26B-56-DL Invader c/n 27666 44-34388/34392 Douglas A-26B-55-DL Invader c/n 27667/27671 44-34393 Douglas A-26B-56-DL Invader c/n 27672 44-34394/34398 Douglas A-26B-55-DL Invader c/n 27673/27677 44-34399 Douglas A-26B-56-DL Invader c/n 27678 44-34400/34404 Douglas A-26B-55-DL Invader c/n 27679/27683 44-34405 Douglas A-26B-56-DL Invader c/n 27684 44-34406/34408 Douglas A-26B-55-DL Invader c/n 27685/27687 44-34409 Douglas A-26B-56-DL Invader c/n 27688 44-34410/34412 Douglas A-26B-55-DL Invader c/n 27689/27691 44-34413 Douglas A-26B-56-DL Invader c/n 27692 44-34414/34416 Douglas A-26B-55-DL Invader c/n 27693/27695 44-34417 Douglas A-26B-56-DL Invader c/n 27696 44-34418/34419 Douglas A-26B-55-DL Invader c/n 27697/27698 44-34420 Douglas A-26B-56-DL Invader c/n 27699 44-34421/34422 Douglas A-26B-55-DL Invader c/n 27700/27701 44-34423 Douglas A-26B-56-DL Invader c/n 27702 44-34424/34472 Douglas A-26B-55-DL Invader c/n 27703/27751 44-34473/34477 Douglas A-26B-60-DL Invader c/n 27752/27756 44-34478 Douglas A-26B-61-DL Invader c/n 27757 44-34479/34480 Douglas A-26B-60-DL Invader c/n 27758/27759 44-34481 Douglas A-26B-61-DL Invader c/n 27760 44-34482/34483 Douglas A-26B-60-DL Invader c/n 27761/27762 44-34484 Douglas A-26B-61-DL Invader c/n 27763 44-34485/34486 Douglas A-26B-60-DL Invader c/n 27764/27765 44-34487 Douglas A-26B-61-DL Invader c/n 27766 44-34488/34489 Douglas A-26B-60-DL Invader c/n 27767/27768 44-34490 Douglas A-26B-61-DL Invader c/n 27769 44-34491/34492 Douglas A-26B-60-DL Invader c/n 27770/27771 44-34493 Douglas A-26B-61-DL Invader c/n 27772 44-34494/34495 Douglas A-26B-60-DL Invader c/n 27773/27774 44-34496 Douglas A-26B-61-DL Invader c/n 27775 44-34497/34498 Douglas A-26B-60-DL Invader c/n 27776/27777 44-34499 Douglas A-26B-61-DL Invader c/n 27778 44-34500/34501 Douglas A-26B-60-DL Invader c/n 27779/27780 44-34502 Douglas A-26B-61-DL Invader c/n 27781 44-34503/34504 Douglas A-26B-60-DL Invader c/n 27782/27783 44-34505 Douglas A-26B-61-DL Invader c/n 27784 44-34506/34507 Douglas A-26B-60-DL Invader c/n 27785/27786 44-34508 Douglas A-26B-61-DL Invader c/n 27787 44-34509/34510 Douglas A-26B-60-DL Invader c/n 27788/27789 44-34511 Douglas A-26B-61-DL Invader c/n 27790 44-34512/34513 Douglas A-26B-60-DL Invader c/n 27791/27792 44-34514 Douglas A-26B-61-DL Invader c/n 27793 44-34515/34516 Douglas A-26B-60-DL Invader c/n 27794/27795 44-34517 Douglas A-26B-61-DL Invader c/n 27796 44-34518/34519 Douglas A-26B-60-DL Invader c/n 27797/27798 44-34520 Douglas A-26B-61-DL Invader c/n 27799 44-34521 Douglas A-26B-60-DL Invader c/n 27800 44-34522/34585 Douglas A-26B-61-DL Invader c/n 27801/27864 44-34586 Douglas XA-26F-DL Invader c/n 27665 44-34587/34617 Douglas A-26B-61-DL Invader c/n 27866/27896 44-34618/34753 Douglas A-26B-66-DL Invader c/n 27897/28032
Specification of Douglas A-26B-15-DL Invader:
Engines: Two Pratt & Whitney R-2800-27 or -71 air-cooled radials, each rated at 2000 hp for takeoff and 1600 hp at 13,500 feet. Performance: Maximum speed 355 mph at 15,000 feet. Cruising speed 284 mph. An altitude of 10,000 feet could be attained in 8.1 minutes. Service ceiling 22,100 feet. Normal range 1400 miles, Maximum range 3200 miles. Dimensions: Wingspan 70 feet 0 inches, length 50 feet 0 inches, height 18 feet 6 inches, wing area 540 square feet. Weights: 22,370 pounds empty, 27,600 pounds loaded, 35,000 pounds maximum. Armament: Six forward-firing 0.50-inch machine guns in nose. Forward-firing armament could be supplemented by eight 0.50-inch guns mounted in four-gun twin packages mounted underneath the outer wing panels. Two 0.50-inch machine guns in remotely-controlled dorsal turret. Two 0.50-inch machine guns in remotely-controlled ventral turret. An internal bomb load of 4000 pounds could be carried Maximum total bomb load of 6000 pounds.
Specification of Douglas A-26B-60-DL Invader:
Engines: Two Pratt & Whitney R-2800-79 air-cooled radials, each rated at 2000 hp for takeoff, 2350 hp with water injection. Performance: Maximum speed 355 mph at 15,000 feet. Cruising speed 284 mph. An altitude of 10,000 feet could be attained in 8.1 minutes. Service ceiling 22,100 feet. Normal range 1400 miles, Maximum range 3200 miles. Dimensions: Wingspan 70 feet 0 inches, length 50 feet 8 inches, height 18 feet 6 inches, wing area 540 square feet. Weights: 22,362 pounds empty, 26,000 pounds loaded, 41,800 pounds maximum. Armament: Eight forward-firing 0.50-inch machine guns in nose. Three 0.50-inch machine guns mounted in each of the outer wing panels. Two 0.50-inch machine guns in remotely-controlled dorsal turret. Two 0.50-inch machine guns in remotely-controlled ventral turret. An internal bomb load of 4000 pounds could be carried. Maximum total bomb load of 6000 pounds.
- United States Military Aircraft Since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian Institution Press, 1989.
- McDonnell Douglas Aircraft Since 1920: Volume I, Rene J. Francillon, Naval Institute Press, 1988.
- American Combat Planes, Third Enlarged Edition, Ray Wagner, Doubleday, 1982.
- E-mail from Bob McFarland on entrance and exit from the A-26.