The Joys of Major Modifications

Brian Martinez

Originally published October 1997

(An e-mail from Brian to another Q-200 builder)

What I've seen since day one on 557BM is a back wing that wants to go flying before everybody else on the airplane. Having a copilot on board really helps the thing behave better. I had assumed that my original leveling boards were good and that the aircraft was set up right. The first hint that something might be a little different was when my taxi testing got fast and the tail went up in the air.

During first flight I ended up driving my reflexer to maximum aileron trailing edge up. Then I had to dial in 8 degrees of trailing edge down elevator. There is still a good bit of pitch authority there, but you are carrying trim drag and I essentially lost a great trimming device in the reflexer (mine is powered by a electric actuator via a coolie hat switch on my control stick) because it needs to stay where it is. Several months into flying the thing Gene Sheehan stopped by to see how everything was going and I told him about my laundry list of problems. After fixing the venting problem that vexed my Ellison (By the way, I'm back to using the TBI with good results) I again spoke to Gene about the 8 degree trim thing. He said, based upon his experience, I would need to change the incidence of one of the flying surfaces. He estimated about 2.5 - 3 degrees. He also said that you've "got what you got" no matter what you set the wings to. Gene said I could change the canard or the wing. He said another option was to change the outboard slot cores on the wing to a little trailing edge up, but I never liked that since that's another trim drag problem. He also told me to just keep flying it as long as I felt comfortable with the handling qualities, which is what I did. I figured I'd eventually do the back wing since there was less to move around.

Anyhow, I was getting a little irritated with not having my reflexer fully engaged and tired of the trim so I decided to do a little research into what I had. I made up some new leveling boards with the little angle finders epoxied to the level lines and it showed a 2 degree error.

So, Saturday I got started and by 1800 Sunday I had the wing free. It took me 16 man hours working alone to get this far. I don't care what a lot of other folks have said...this is a major pain-in-the-butt. I had to split the seat back bulkhead and the FS-94 bulkhead at the top. I'll have a number of repairs to do before its all over. Sometime this week I should be able to get back up to Mojave to finish the sanding and get the wing retacked. I'm estimating a three and a half week down time.

I went through 100 fluid ounces of water at Mojave today (I wear a Camelback hydration system when I work on the plane up there and I just plain sucked it dry) and I was still parched. As I write this, I still have a dehydration headache.

You don't ever want to have to do this, friend, because it puts you back on the emotional roller coaster. And, of course...I'm itching all over from the glass dust.


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Revised -- 22 April 1998