Brewster Buffalo XF2A-4

[cthornburg]

Haven't been able to find a pix of XF2A-4 pressurized version of the Buffalo. BuNo.1388 mod in Aug. 1941. Interested to see how the canopy was modified and the rest of the aircraft.

Chris

 

[Wurger]

All sources say XF2A-4 a modified F2A-3, BuNo 01516 but not 1388.

 

[vikingBerserker]

Only thing I can find is it had a 4 blade prop.

 

[cthornburg]

Just checked further said c/n 3 was maybe 1388 which is where I got that info on another site.

Thanks
Chris

 

[vikingBerserker]

I found my copy of F2A Buffalo in action by Squadron. It does state the XF2A-4 was converted from an F2A-1 airframe (page 45). The only thing I could find on BuNu 01516 was it was used at NACA to study flaps from 42-43.

http://history.nasa.gov/SP-3300/ch4.htm

 

[fubar57]

In the Kagero Publication, a captions states that the F2A-4 would have carried 20mm cannon in place of the .5" Brownings.

Geo -----

 

[blueskies]

I found my copy of F2A Buffalo in action by Squadron. It does state the XF2A-4 was converted from an F2A-1 airframe (page 45). The only thing I could find on BuNu 01516 was it was used at NACA to study flaps from 42-43.

http://history.nasa.gov/SP-3300/ch4.htm

Found a few NACA windtunnel tests that seem to back this up.

Several are for full span slotted flaps on the Buffalo, dates are in a range from '41 to '43.

Additional power-on wind-tunnel tests of the 1/8-scale model of the Brewster F2A airplane with full-span slotted flaps : UNT Digital Library
Power-on wind-tunnel tests of the 1/8-scale model of the Brewster F2A airplane with full-span slotted flaps : UNT Digital Library
Power-off wind-tunnel tests of the 1/8-scale model of the Brewster F2A airplane : UNT Digital Library

And the most interesting one is tests with a new tail;
Power-on longitudinal-stability and control tests of the 1/8-scale model of the Brewster F2A airplane equipped with full-span slotted flaps and a new horizontal tail : UNT Digital Library

Skimming through these documents I don't see any mention of a pressurized cockpit.

And here is a document on flight tests of the Buffalo with slotted flaps. A few photographs of the bird are included;
Flight tests of F2A-2 airplane with full-span slotted flaps and trailing-edge and slot-lip ailerons : UNT Digital Library
Calculated and measured turning performance of a Navy F2A-3 airplane as affected by the use of flaps : UNT Digital Library

 

[Capt. Vick]

Been looking for Jim Maas email address to ask him if he knows anything. He literally wrote a book on the Buffalo and seems to be a genuinely nice guy. Haven't written to him in years however...

 

[Capt. Vick]

From Jim Maas:

Hi Jim - Sadly, I have not seen any pictures of the XF2A-4. I don't believe it ever carried 20 mm cannon - this was an armament experiment tried with the prototype XF2A-1 (along with other armament variations). The XF2A-4 was a conversion from Bureau Number 1388, which started out as an F2A-1, then was converted to an F2A-2, and then to the XF2A-4. Here's the technical spec for the XF2A-4:

NECESSARY CHANGES IN THE

DETAIL SPECIFICATION OF F2A-2 AIRPLANE

1a. The changes in this specification apply to the modifying of an F2A-2 airplane to include a pressure cabin and a turbo supercharger for the engine for operation at high altitude.

102a. The gross weights are estimated to be as follows:

Modified Fighter (75 gals. Fuel) 5632 lbs.

Modified Fighter (75 gals. Fuel and 1 Wing Gun Instal.) 5760 lbs.

113a. The estimated performance is given on the curves of this report.

201a. Bomb release controls shall be omitted.

201b. The arrangement of the airplane shall be substantially the same as the F2A-2 airplane except as indicated on N.A.F. Drawing No. 68599 and N.A.F. Sketch No. 1618.

201c. Controls shall be provided in the cockpit for one non-synchronous gun in the wing.

329c. Strength calculations shall be made for the effect of static internal pressure corresponding to the pressure difference between 8,000 feet and 40,000 feet with a safety factor of 1.5 rather than 1.15 on yield. No static or dynamic tests other than a pressure test of the enclosed cabin shall be required.

329d. Allowable accelerations shall be less than those of the F2A-2 type airplane if calculations indicate the necessity for a reduction, but shall not be less than those of a VR airplane.

349a. The overturn structure shall be redesigned as necessary to avoid interference with the pressure bulkhead.

366-367. Additional vent holes shall be drilled in the upper surface of the wing.

These holes are to be plugged if the airplane is restored to normal operation.

377a. The flap controls shall be hydraulic as on the F2A-2 airplane unless high altitude operation indicates the necessity for another type of system.

413b. The portion of the fuselage from the firewall to the rear pressure bulkhead shall be insulated against heat exchange from the inside to the outside.

420a. The cockpit shall be enclosed in substantially the same manner as the F2A-2 airplane except as modified to withstand internal pressure and to provide heat for the prevention of frost and its formation.

420b. The telescopic gun sight and provisions for its installation shall be removed. Provisions shall be made for the installation of a reflector type gun sight.

420c. The pressure sealing latches shall be operated from the inside only and shall be capable of quick release for emergency exit.

428a. Adjustable engine cowl flaps shall be provided.

435. The portion of the windshield directly forward of the pilot shall be of flat, laminated glass. The remainder of the windshield shall be spherical in shape and shall be made of either laminated glass or a transparent plastic. All transparent sections shall be double with provision for passing heated air between the panes.

A windshield wiper for the outside flat section of the front windshield shall be provided. Provisions shall be made for the applications of alcohol to the windshield at the wiper.

500a. The power plant arrangement shall be in accordance with the attached sketches.

502a. The carburetor shall be tested and adjusted as required for proper metering.

503a. The R-1820-40 engine with a turbo supercharger and a two speed mechanical supercharge is estimated to give the performance indicated on the attached curves.

523a. An intercooler shall be provided between the supercharger and the carburetor. A manually operated shutter shall be provided for the control on the intercooler cooling air.

529a. The exhaust collector shall discharge into the turbo supercharger. A suitable flexible joint shall be provided between the exhaust collector and the turbo supercharger.

535a. The vacuum pump and oil separator shall be removed.

537a. A fuel-air ratio analyzer shall be provided.

551a. A three-bladed Curtiss Electric constant speed propeller (10'-3" dia.) having a pitch range of at least 50 degrees, shall be provided.

592a. The 18-point thermocouple equipment shall be installed and included in the weight empty.

701-702. The fuel supply to the carburetor is to be maintained by air pressure in the

fuel tanks through a connection to the intake manifold.

I hope a photo will eventually show up someday!

All the best - Jim

 

[fubar57]

Wow, that guy really came through

 

[Capt. Vick]

I'll say, but sadly still no photo. Makes me wonder if it was ever built...just sayin'.

 

[fubar57]

Just found this on line, don't know if it's all ready posted or not. I'll add it to the U.S. technical section as well.