The Airmaster Cessna C-37 was a “Crash Sale” special from Hobby Lobby. I think the bird was on sale for around 60+ bucks. It’s a decent sub .40 size bird with a great classic look to it. The plane quickly picked up the nickname “Nude Bird” due to its skin tone coving.
The Box was well packed with no sign of damage to the construction of the plane. The classic aviation look is very appealing to the dudes. This dude especially, loves the looks of the old timer, kit built looking planes. However, we were not in love with the color or material used for the covering. The covering is more like an adhesive sticker than the tight heat shrink covering that we have become accustomed to in many of the AFRs on the market. It’s very tempting to remove the current covering and replace it with a more desirable custom look. Before putting in the extra time and cash for new covering, let’s see how this thing flies first.
The Cessna was purchased as a .25-.35 glow plane with the full intention of converting over to electric power. There were no surprises with the building of the plane. The installation of the control surfaces and the push rods went well. Standard servos had plenty of room within the fuselage. Both dudes were very impressed with the solid construction of the Cessna. The installation of the Jetti 15-3 in-runner went in with very little modification required. That same thing cannot be said for the battery placement while still keeping true to the plane’s center of gravity. The CG is one, if not the most important part of the build. When converting a glow powered plane to electric, planning for the placement of the battery and battery box in relation to the CG should be considered early in the build. If a builder is not careful, a converted plane can easily end up with the CG out-of-wack and unwanted led weights will need to be added to properly balance the plane. A few tricks are to use variable size motor mounting posts. Use shorter or longer posts to get the weight of the motor closer or farther from the planes firewall. Before making any modifications to the plane to accommodate the battery/battery box, place the plane on a sturdy CG scale, carefully lay the battery on the outside of the fuselage and move the battery around until you can get the plane to balance on the CG as close as possible. Try using different size/shape battery packs. In the case of the Cessna, the plane was tail heavy the motor needed to mounted on long motor mounts and the battery needed to be installed as close to the firewall as possible (the firewall needed to be cut to allow the batter pack to actually pass through the firewall).
The night before the maiden flight, all the control surfaces were set to factory specs. At the field a pre-flight check was preformed to ensure proper operation of all control services. When satisfied, the plane was cleared for takeoff.
The plane sat poised for takeoff into the oncoming wind. The throttle was slowly advanced as the plane taxied down the dirt runway. At full power the plane was quickly running out of runway and did not “feel” as it was going to get off the ground. The elevator was pulled back and the Cessna slowly lifted off the ground and took flight. Slowly gaining altitude into the wind, both dudes decided it would be for the best to return to base, land and rethink the power system of the Cessna. Once airborne, the Cessna required very little trim adjustments. The throttle stick was at max but the plane was obviously flying severely under powered. The Cessna seemed to be gradually gaining more altitude. The dude decided to give the bird one more lap. Little did he know, it would be the Cessna’s final lap.
As the Cessna turned into the wind the bird slowly started to lose air speed, a slight turn to the left and the Cessna tip-stalled and tumbled to the ground. The crash site revealed hours of hard work now lay in a pile of shattered balsa. The plane was a complete loss. The servos and motor were tested in the shop for possible recycling into a new plane at a later time.
The look and short maiden flight of Cessna was enough to place a call to Hobby Lobby to acquire a replacement. The dudes learned some valuable lessons with this failed bird that would stay with us to this day.
