I purchased this P-38 from a friend at bomber field. It is powered by 2 3w-42s, has over 100 inches of wingspan and weighs 37 lbs. It has been flown 6 times before I bought it. The 3w engines are completely concealed and the only protrusions are the spark plug caps and exhaust pipes.
Here is a shot of the belly, showing the gear doors and the small air cylinders that actuate the doors.
Here is a shot of the UP3 gear door sequencing valve. The gear retracts, and the doors close after a short pause. On extension, the doors open and then the gear extends after which the doors stay open.
Hatch located under the nose, housing the switches, air fill and fuel fillers.
Left side elevator servo is mounted inverted to do away with the need fo a servo reverser.
Servo operated brake valve.
Gear door air cylinder
Black area is re-inforced with carbon fiber mat.
11/11/02. First flight on the P-38. The plane flew fantastic, its easy to control in the air, very stable and fast. The picture is rather grainy as my camera is not made for this sort of thing. Still need to do some engine tuning to get both motors running evenly in the air.
Here she is all ready to go for her first flights. Props are apc 20x10s
These shots were taken at my flying field under construction. In the background is a shade structure that Im building to have some refuge from the summer sun. Also visible is the windsock that I got from Sporty's pilot shop. Asphalt runway is 660 ft long and there are no obstructions around the field, just open grass and small brush.
UPDATE 12/30/02
The 3ws were found to be unsuitable for the P-38. They were sold to a freind and new zdz40s were purchased as replacements. Some work was required to fit the new engines as they have different mounting requirements.
The zdz40s needed to be spaced forward from the stock firewall approx 1 1/4" . A spacer was made from 5 layers of 1/4 ply, the first layer being much larger to spread the load of the engine mounting. The first layer is also screwed to the existing firewall. 1/4-20 X 3" mounting bolts pass thru all 5 layers and thread into blind nuts on the inside of the fuse.
5 layers of ply cut to shape and attached to the firewall.
Throttle horns were made from 1/16th G-10 which is a very hard phenolic type of material.
Zdz 40 installed.
Muffler/ pipe was made from 1" square tubing and electrical conduit brazed together.
4-40 rods connect the carb to the throttle servo and choke lever. The carb protrudes into the fuse about 1/4 inch.
The new motors fit entirely within the cowling except for the spark plug cap and exhaust outlet.
Installation of the zdz's lightened the plane by amost 3 lbs. Unfortunately, most of that weight was forward of the CG. 2 lbs of nose ballast was needed to bring the now tailheavy model back to balance. Formers were installed in the nose, under the switch plate to take a removable nose weight block.
The nose weight block was made by melting lead into a small tin form. Holes were then drilled into the lead block for the attachement bolts. The block was made removable so fine tuning of the CG can be accomplished easily.
Baffles were made from 1/16th light ply to direct cooling air to the cylinder head.
Temp was measured after a 10 min flight and cly head showed 170 deg which is relatively cool.
