Introduction
A few years ago, I watched some people at Deer Valley Airport, near Phoenix, convert a North American AT-6 into a "replica P-64". The conversion involved replacing the engine with a Wright R-1820, clipping the wingtips, and revising the rear fuselage to conform to the single seat configuration of the P-64. It was an interesting project, but it still looked to be like a humpbacked AT-6 with a three bladed prop and bigger engine.I guess it is still flying, although I haven't seen it lately.
There is another one flying, this one a Harvard conversion, which has a totally inaccurate rudder. I first saw this in the hangar at Chino, CA, being rebuilt, and have since seen it at several fly-ins. Photos of both accompany this article.
I actually did this conversion many years ago, using an old Hawk kit, and wrote about it in the old Dirty Plastic publication that IPMS Phoenix used to circulate. The conversion is long gone, and since I wanted to build another one, seeing the Harvard on the shelf, and knowing that I would never build it as a two-seater, I decided, why not?.
History
The P-64, or NA-50A, was developed by North American Aviation in the late thirties to sell to third world countries that needed an "el cheapo" fighter. It was basically an AT-6 type airframe which was shortened in length and span, and equipped with a Wright R-1820-77 engine rated at 870 hp. Seven were delivered to Peru in 1939, and a modified version, featuring a cleaner cowling and an AT-6 type rudder, were ordered by Siam in 1940 under the designation NA-68. Six were produced, but before they could be delivered, they were taken over by the U.S. Government due to the Japanese occupation of Siam in 1940, and eventually delivered to the Army Air Corps as P-64's. The Army didn't really consider them fighters as they were hopelessly outclassed by more modern types, but they were assigned to Luke Field, Arizona, where they were used as fighter trainers and hacks throughout the war. They must have been a lot of fun to fly, and one was saved from the scrappers by Jack Canary, who had flown them during the war. The lone survivor spent some time in Arizona and Mexico before finally being acquired by the Experimental Aircraft Association, in whose museum collection at Oshkosh, WI, it resides today.
The P-64's (AF 41-19082 to 41-19087) were delivered in RAF type camouflage, presumably dark green and dark earth over a pale grey color, although the undersides could have been light blue. There are color drawings available of North American A-27's, an attack bomber version of the AT-6 which Siam ordered and which were acquired by the Army in the Philippines at the same time, and these drawings show pale grey, so I'll go with that color. The original P-64's had 20 mm cannon housings under the wings, carrying a total of six weapons, but although these show in one photo, most photos of the airplanes show clean wings. At least, that's how they were operated at Luke Field. At first the aircraft had the three color camouflage with the old "star and ball" insignia of 1941, with no numbers showing, but one later photo shows later "star and bar with red border" insignias with a yellow serial and cowling number, so I chose to model that particular aircraft. A good photo exists in the "In Action AT-6" booklet, while other photos of the aircraft in the earlier markings are available on-line, including probably the best photo of all, a good side view shot by premier aviation photographer William T. Larkins during 1941. Another photo, taken by Lt. Barry M. Goldwater, later an Arizona senator and presidential candidate, shows a P-64 directly over Luke Field in late 1941.
Research
Information on the P-64 is rather sketchy, and although there are several 3-view drawings circulating, both show a completely different wing from that of the AT-6. As it would have been uneconomical for North American to totally redesign the wing for about a dozen airplanes, it seems probable that they just shortened the wings by about 5 feet, and redesigned the forward part of the center section to accommodate the retractable landing gear. Side view drawings seem to conform to the photos available, but an examination of the only surviving example at the EAA Museum at Oshkosh is needed to be absolutely certain as to the wing's configuration. But neither 3-view drawing is accurate in this respect. I went with the AT-6 wing. It must be remembered that the Oshkosh P-64 has a modified engine cowling, and that the canopy has been changed somewhat over the almost 60 years that the airplane has been privately owned. And it is painted almost like a Boeing P-26, with a black fuselage and chrome yellow wing.
The Kit
The Airfix Harvard has been around for a long time, and has been reissued numerous times. It is basically accurate in outline, but lacks the detail of more recent offerings. It does, however, provide the basics needed for this conversion, as the fuselage will be essentially rebuilt from behind the wing to the firewall. The pilot's canopy and windshield can be used, but the rear, fixed position canopy has to be vacuformed, which I did using the rear portion of the Airfix canopy as a mold. The engine must be replaced, and I found that the cowling and prop from an Airfix SBD Dauntless was perfect, although some rework was necessary to get rid of the gun troughs and exhaust stacks.Of course, the whole thing needs to be smoothed, getting rid of the "boiler plate" rivets that were so common in kits of this era.
Basic Assembly
The photos will illustrate the basic assembly process. First, the fuselage was cut behind the wing trailing edge. The rear fuselage was about one foot shorter. In addition, the firewall must be shortened slightly to allow for the larger cowling of the SBD. When reassembled, I lined up the bottom line of the fuselage so that the gap was at the top, because that was the part that would be covered over with putty as the turtle deck fairing was constructed. The wings were cut off about 3 feet inboard, allowing for the new wingtip bows to be attached. After trying several alternatives, I merely trimmed down the portions I had just cut off, and they worked fine. Besides, they were the same thickness, so trimming was minimal. The wing center section had to be totally rebuilt, since the wheel wells were entirely different from the AT-6. I used plastic card for this.
Next, I began working on the fuselage. The front and rear sections were joined, and I began building up the rear portion with putty. I use automotive Bondo, and it works fine. I also built up some of the forward fuselage, using a piece of strip styrene to establish the proper outline for the rear fuselage fairing. I then used a thin piece of styrene to construct the rear co*ckpit aft portion, which is curved. This allowed filling in to get the proper outline. This involved a lot of filling and sanding, as this type of putty must be installed in thin layers. It just took a lot of time, but eventually a smooth finish of the right outline was achieved.
I then detailed the engine, and masked off the engine part. I drilled two holes where the machine gun barrels protrude, using plastic rod for the actual units. These were drilled out to simulate the gun barrels. At that point, I installed the canopy and windshield, and masked off the clear portions for painting. Once masked, the plane was ready for the paint shop.
Painting was easy. A base coat of pale grey (in this case, Model Master RAF dark sea grey), followed by RAF dark earth, which after masking, provided a base for RAF dark green. Insignias came from Microscale, or whatever they are called this month, and numbers came from another Microscale sheet of yellow AAF letters and numbers.
Detailing involved use of the kit landing gear and wheels, using built up card wheel covers. The kit tailwheel was used, and a radio mast was made from plastic rod. The LF antenna is rather odd, as it runs from a mast on the rear spine of the fuselage down to the left wingtip, a most unusual arrangement. The single exhaust stack was made from an old plastic coffee stirring rod, suitable trimmed to shape. I did some very light weathering and paint chipping, as photos show the airplane in pristine condition. Other than that, there wasn't much to it.
I seem to have accumulated a collection of 1/72 scale U.S. Army fighters over the years, and the P-64 fills a gap in the series. It is not a difficult conversion, even though the fuselage required major surgery. I think my conversion is easier than trying to do it with an Airfix Boomerang (a parallel development), although I haven't really investigated this possibility. And it was fun, which, I think, is the point of all of this.Try one, and you'll be the only kid on the block to have a model of a P-64.
