liftzone - A nice review of building the Kelly (We followed most of the advice here)

July 10th 2004 - Pre-Flight Foto Shoot

The kelly is finally ready after a month of work. We probably spent 20 to 30 hours all together building it, and decided to do a little photo shoot before we went flying.

This is the closeup of the electronics in the front. We have a 280 Graupner motor, three quarters (the 25cent kind) below it for balance, a very light Kokam 700mah Lithium Ion battery (below the radio), a Jeti speed controller, a Hitec feather receiver and two Hitec HS-55 servos. We decided to place the battery in front of the servos (in the plan, it was in the back), in order to shift the weight forward since we would use the lighter Lithium Ion batteries rather than NiMh. Despite this, we had to put some quarters in the front to make it balance right. The only other modification we made to the plane was strengthening the firewall by gluing circles, cut out from old credit cards, to the front and the back of the balsa. I am really glad we did this, because the supplied balsa would have surely broken from the nose-down landings of our first flight.

A detailed view of the rudder connection. I used a Z-Bend instead of a piece of tubing as in the instructions.

A detailed view of the elevator connection. Not the most beautiful thing in the world, but it works. Probably, it would have been better to take the advice of the liftzone review and use a more flexible pushrod, routing it out the back. Instead we just put a 90 degree bend into the metal pushrod that came with the plane, and left it to move vertically up and down (the bend is not visible in the picture... it is right behind the rudder).

Fang holding the plane.

Even the plane's shadow is cool.

Me holding the plane.

July 10th 2004 - First Day at the Field

The kelly survived the first day at the field. It flew beautifully, although it was a little bit underpowered and hard to get high up in the air. We got three flights in. During the first flight, I was still a bit rusty from not having flown for a year, so I almost hit a tree, and narrowly missed the light posts on our field several times. The landing was a perfect bounce on the grass. The flight lasted 5-10 minutes. I then crashed the plane trying to take off the next two times, but nothing broke except for a little crack in the propeller nose-cone. The wings are incredibly strong, and survived all the roll overs. I took off on the third attempt and flew around for about 15 minutes. It was a lot more fun this time since I was more relaxed, and I even did two loops. One thing that amazed me about the kelly is how well it turns without ailerons. In fact, using the rudder made it bank as if it had ailerons. This was a comlete surprise. Originally, I was thinking of adding ailerons myself, but I'm glad I didn't. Afterwards, Fang tried to take off, but a slight wind blew the plane over, and it hit the ground cracking the nose cone badly. We had to go home and get another nose cone. Once we were back, Fang tried to take off two more times, but was unsuccessfull, partially cracking the new nose cone, so I tried to do it for her. Unfortunately, our battery ran out just as I was trying to gain some altitude. I didn't realize we were running out of juice, so I almost crashed the plane, but was able to pull up just in time so that it ended up hitting the grass with its belly, bouncing a few meters into the air, flying a little, and then landing softly. All in all, it was a great day... lots of fun flying, lots of close calls, and the kelly stood up to it all. I can't wait to go flying again.

For our next flight, I plan to get a new motor, the Graupner RACE 280, which should give about 5 oz of thrust compared to the current 3. Also, I'll get the Kokam 1200 mah cell, and get rid of the quarters that I have in there now to compensate for the added weight. Another thing I learned is that you can put the speed controller on "Brake" setting rather than the regular setting. This will cause it to stop abruptly when power is low. This way, I'll know when the power is low, rather than thinking that there is still power, and trying to continue flying. Finally, I'll try drilling a few holes in the motor mount to allow air to get through to cool the motor.