• The A-26 was the first bomber to use an NACA 65-215 laminar-flow airfoil, double-slotted flaps and remote-control turrets
• It took just 28 months to go from first flight to combat operations.
• A most unusual feature of the A-26 was the aluminum alloy monocoque engine mount, which was a combination of structure and cowling, thereby reducing weight and easing engine installation. Another special feature was the Douglas devised slotted wing flap, which had a lower pitching movement for a given lift coefficient than the Fowler flap. Finally, the engines were cooled with a new type of high entrance velocity cowling. This cowl induced less aerodynamic resistance and lowered the temperatures of the engines.
• The original A-26B from the Pilot’s Training Manual was listed as having 6 configurations for the "All Purpose Nose" (The B model) – not counting the original two "4-pack" gun pods option that could be mounted under the wings (before the 6 internal .50's - 3 per wing - were incorporated)
• Each nose could be changed in about 24 hours by field personnel.
• Eventhough the aircraft had eight .50-caliber machine guns in the nose, to reduce exhaust fumes in the cockpit during firing, normally only six were loaded
• In 1941 the cost of an A-26 was $224,498, by 1945 the cost had dropped to $175,892
• The bomb bay lights remained on while the doors where open during a bomb run, so it got a little sticky at times over the target. Ground crews would often disconnect the light or by pass it through a switched circuit.
• The Douglas A-26D Invader was an improved version of the solid-nosed A-26B, with more powerful engines. A single prototype was produced, probably by fitting a standard A-26B with two Chevrolet built 2,100hp R-2800-83 engines. This increased the aircraft's top speed by 80mph, and Douglas received an order for 750 A-26Ds, but this was cancelled after the end of the war in the Pacific and before any aircraft had been completed.
• In September 1944 the 553rd Bomb Squadron at Great Dunmow, England received 18 machines. 11,567 missions were flown, delivering 18,344 tonnes (18,054 tons) of bombs. One aircraft was even credited with a probable 'kill' of an Me 262 jet fighter.
• RAF fighter ace James Edgar "Johnnie" Johnson, flew reconnaissance missions in B-26 Invaders
• Some Invaders that operated from a shorter ( say 4,000' runway ) were instructed to use a unique procedure. The idea was to use full flaps on final, and then retract the flaps immediately after touchdown to get better braking action on our rollout.

 

 

 

As a point of interest, the following Invaders passed through London Gatwick Airport:

 

• D-BACA On Mark Marketeer (29217 ex 44-35938, N4203A, N510X, N516X)
  Registered to Luft-Transport Dienst GmbH when visited Gatwick on 28/07/71. W/O landing at Zurich 23/02/73 & burnt for fire practice 05/07/73.
• N60XY On Mark Marksman (28040 ex 44-34761, NX67158, N67158, N400E)
  Owned by Occidental Chemical Corp when visited Gatwick on 23/11/71. To N60XX & presumed crashed or abandoned during drug operations.
• N300V On Mark Marketeer (27895 ex 44-34616, N2890D)
  Owned by Daniel G van Clief when made the first of several visits to Gatwick on 03/05/63, arriving from Reykjavik & departing three days later to Milan. Last heard of as sale reported in the USA in 1978.
• N4000K Wold Invader Executive (28041 ex 44-34762, NX67880, N4000)
  Owned by Aero Service Corp when made the first of several visits to Gatwick on 02/05/63, arriving from Keflavik & departing ten days later to Amsterdam. Abandoned at Dili, Portuguese Timor in 1975 & last reported in 1986.
• N5294V On Mark Marketeer (6928 ex 41-39215, N5292V)
  Owned by M Avoffson when arrived at Gatwick from Reykjavik on 01/08/61 & departed to Madrid three days later. To N4000M, N200M, N142ER. Under restoration with USNAM, Pensacola, FL as JD-1 "77141".
• N7079G On Mark Marketeer 28841 44-35562, Operated by Lady Barbel Abela & Len Perry, London, UK, 1991-1992.- Flown as Bar-Belle Bomber. July 12th, 1992 - LYDD TO CANNES, July 15th, 1992 - CANNES TO LYDD, July 19th, 1992 - SOUTHEND TO HELSINKI

 

 

Ted Smith who designed the A-26, later went on to design the Aero Commander, notice any similarities.

Below, On Mark proposed a turboprop version of their corporate design, the On Mark 450, using Allison 501s. The fuselage was drastically modified.

The On Mark Model 450 was a projected high-speed executive transport powered by two Allison 501D turboprops similar to the powerplants of the Lockheed Electra. Production of each aircraft involved the fabrication of a complete airframe from scratch. In particular the fuselage was completely new with a cylindrical cross-section 90in in diameter, with AiResearch cabin-conditioning and pressurized to an equivalent cabin altitude of 5,000ft at 30,000ft using engine-driven blowers. The standard interior would have seating for fourteen passengers.

Owing to the high cost of the Allison engine, it was thought that complete powerplants may have been leased to operators on a per-hour basis; this was expected to reduce the purchase price of the aircraft from $lm to about $800,000. Flight testing of the first aircraft was due to begin in the summer of 1957, with the first customer (Maytag Aircraft Corporation) scheduled to take delivery of the first production Model 450 early in 1959. On Mark was expected thereafter to produce two aircraft monthly for 60 months.

On Mark had also purchaced Nineteen surplus B-26s from the U.S. Air Force and a number of these would have been used for making up kits and basic parts for the new turboprop Model 450.

On Mark only managed to built a model and partial mock-up of the Model 450, but after a lot of deliberation, the project was shut down.