Monday, June 19, 2006

[AC] Apollo Mission... FAIL!!

Date: 16, June, 2006
Time: ~8:00-9:00?
Location: Chan-bûn-khe, Sai-káng tōa-kiô
Weather: Sunny day!!

I have not fly RC aircraft for several years. Recently, I pick up some "remeains" in our lab, and plan to build up an aircraft for some simple flight test (e.g. new GPS receiver or other payload test).

After about 2 days' efforts, I assemble a 30 class RC aircraft named APOLLO, because its wing has this word. I have no idea where this wing come from. I choose this wing becuse its wingspan is about 180 cm, longer than other normal one's wingspan from 130 cm to 140 cm. I think this wing could offer more lift then I can use this APOLLO to carry more payload for some test.

But I never think this choice could affect the flight characteristic so much that might be one of the causes induced APOLLO's crash.

I pushed the throttle stick to lift up APOLLO. Just after its take-off, I realise that my skill is not good enough to fly it properly. APOLLO performed good lift ability but was poor in the rolling maneuver. The roll of APOLLO seemed a little stupid. Another problem is the pitch-up trend under higher throttle. These conditions increased my loads as flied APOLLO.

Luckily, I landed it safely on the grass field (actually I should land it on the runway, but I can't control it very well). After some adjustment about the nose gear (it had a trend to make APOLLO run to the right side), I took APOLLO off again.

Because when I trimmed the nose gear, I also trim the transmitter via the rudder channel. This trim made the rudder deflect to right a little, but I didn't notice it. Therefore, after the long wingspan aircraft took-off, it always turned right! I didn't think about the rudder's trim, I just tried to turn it to left by aileron and took it back.

APOLLO suffered stall twice because the pitch-up trend just mentioned proviously. When it stalled the second time, it was too far for me to recognize its attitude. Then APOLLO began to dive, and I tried to save it back by pull the elevator. Suddenly, I saw one side of the wing flipped!! Of course, APOLLO crashed. =__="

Comments:
  • To change the wing will alter the flight characteritics very much
  • Longer wing is more sensitive about the rudder's deflection. It induce obvious trend of "yaw and roll"
  • APOLLO maybe not a good name of a project...