Douglas A-26D ...

[Mark Allen M]

The Douglas A-26D Invader was intended to be an improved version of the solid-nosed A-26B with more powerful engines. Two different XA-26D prototypes were produced.
The first prototype was made by converting a B-model (44-34100), by fitting two Chevrolet built 2,100hp R-2800-83 engines. This increased the aircraft's top speed by 80mph.
The second prototype was built by modifying another Invader B-model (44-34776) and featured a 4-blade propeller design.
Douglas received an order for 750 A-26Ds, but the order was cancelled after the end of the war in the Pacific and before any aircraft had been completed.

[lucky52]

In the third picture down, could that be the second prototype behind the tail of the first prototype(not that it matters, just curious)? Then again, it might be another B-26 waiting to be painted.

[Mark Allen M]

Looks like these a few lined up behind.

[L-188]

Chevrolet built R-2800's? this is something I never knew. Forgive my ignorance but how many companies built engines under contract?

[quemerford]

LOADS!!! Chevrolet built J35s, as did Allison and General Electric amongst others. I seem to recall an issue with (Ford?)-built J65s ending that contract.

[bdk]

The first prototype was made by converting a B-model (44-34100), by fitting two Chevrolet built 2,100hp R-2800-83 engines. This increased the aircraft's top speed by 80mph.

No way adding a couple of hundred HP increased the top speed by 80mph! What is the source of this info? Must be at different altitudes or something.

[Mark Allen M]

By William Pearce

"The Douglas XA-26D and E were improved versions of the Douglas A-26B and C respectively. Both the XA-26D and E were upgraded with a more powerful version of the Pratt & Whitney R-2800 radial engine, the -83, built by Chevrolet and rated at 2,100 hp (1,566 kW). The engine’s output increased to 2,400 hp (1,780 kW) with water injection. The carburetor air scoops in the cowling were revised along with the carburetors, superchargers, engine mounts, and generators. The aircraft were fitted with wide-cord, 12.7 ft (3.87 m), four-blade propellers with spinners, although three-blade propellers were also tested. The top speed of the XA-26D and E was 403 mph (649 km/h) at 15,000 ft (4,572 m)—about 50 mph (80 km/h) faster than the B and C models—and the climb rate doubled to 2,326 fpm (11.8 m/s)".
https://oldmachinepress.com/2012/09/03/ ... -invaders/

Here's the "wrong" information I originally posted. Ooops!!
http://www.historyofwar.org/articles/we ... e_vignette

[A26 Special K]

Mark, glad you added that other info about the D. I’ve been scratching my head about the 80 thing. Our Special Kay was originally an A-26B block 40 aircraft and was the first block fitted with Ford built 2800-79 engines normally rated at 2100 hp but with water methanol injection, 2300 hp. When she was converted to a K model, R-2800 CB-16’s with water meth that could hit 2500 hp were fitted, but it really didn’t help the top speed. The idea was to load more ordnance 4000 lbs vrs 12,000 pounds. Eight pylons were added to the wings so the drag went way up and it costs us about 30 knots when we load replica ordnance on it.