Great Planes Super Stearman
This is my first foray into the world of biplanes. I admire the classic lines of the Super Stearman, which is a modified version of the original Boeing-Stearman Model 75 . A friend at the flying club has this model and when a new-in-box kit became available at a good price it was time to get one for myself.
|Flight time:||0h 28m|
|Wingspan (upper):||1816 mm (71.5")|
|Wingspan (lower):||1753 mm (69")|
|Length:||1448 mm (57")|
|Centre of Gravity:||140 mm (5.5") from leading edge of upper wing|
|Engine:||DLE 20 (20cc 2-stroke gasoline)|
|Tank setup:||330 mL Fiji bottle, 3-line system|
|Battery:||6.6V 2500mAH A123|
|Power management:||Tech-Aero IBEC Ultra|
|Throttle servo:||Hitec HS-425BB|
|Rudder servo:||Hitec HS-645MG|
|Elevator servo:||Hitec HS-645MG|
|Aileron servos:||Hitec HS-645MG x 2|
A great day for a maiden flight.
It took almost half an hour to get everything unpacked and assembled at the field. I had a friend look everything over and he also acted as my spotter and trimmer for the first couple of flights. After a short takeoff run the plane leapt off the ground and stooged around nose-high as if tail heavy. I had checked the CG before and did so again at the field and I may yet add some nose weight, but in the interim 12 clicks of down elevator solved the problem.
The engine was a little lean in the top end; it sagged and threatened to quit when I throttled up after a low-speed pass, so I richened it an eighth of a turn after landing - that solved the problem. It still pops a bit in the mid range so I am leaning out the low end a tiny bit after each flight. The DLE 20 is an excellent match for this airplane, which cruises between 1/3 and 1/2 throttle. A ten minute flight uses about 90 mL from the 330 mL gas tank (27%).
The aileron throws were too high at first - I dialed those down a little after each of the first two flights. By the third the Stearman was flying beautifully; it is a joy in the air and hasn't shown any nasty tendencies.
I checked before disassembly and was very pleased to find that the plane fits into my truck fully assembled. I was also able to carry it assembled into the basement and set it on the stand. This will cut down on non-flying time on trips to the field.
I recharged the single 2500 mAh A123 battery when I got home; for 27.5 minutes of total flying I put 550 mAh back into it. This gives me more than enough capacity for an event or a typical day of flying.
For more pitcure of the plane in flight and at the field, visit my Great Planes Super Stearman - General album.