sixpacker
Pre-takeoff checklist
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Sixpacker
So enough time has passed that I can now tell this story. 
No, I didn't do anything illegal or something like that. Maybe just a little dumb. I will be the first to admit that I've done plenty of dumb things in my life. The plan is as I get older that I will do fewer and fewer stupid things and learn from my mistakes as I go... So far so good.
Anyway, enough rambling. This particular episode occurred while I owned a 206. I have to admit this is a plane I loved and I miss it. It was a little slow and expensive to operate fuelwise. The engine maintenance was high (I see a thread in the maintenance section on expensive cylinder work right now... Alex I feel your pain been there done that) but besides that the rest of the airframe was inexpensive to maintain. I could practically go anywhere with that plane and almost carry anything. Please excuse me I'm rambling again.
Back to the story. I decided to get the tip tank modification. Flint Aero tip tanks. The tips add three feet to the wingspan but for that you get an almost 200 lbs of gross weight increase. So even if you're not going to use them for holding extra fuel you get to legally load an extra body on your plane.
Have a look at this article though then come right back
http://www.aviationlawmonitor.com/2010/03/articles/general-aviation/the-trouble-with-tip-tanks/
I read about this before ordering the kit so while I'm sure Flint Aero is not thrilled by this story at least in my case it did not affect my decision to get it anyway. I don't know if the installation procedure changed as a result on that particular accident. Either way the installation procedure calls for a fairly detailed process for adjusting the stall warning after installation. More on that later.
I ordered the kit and arranged to have it installed by a local shop. Before I handed it all over I read the installation instructions intensively and was well aware of this stall warning adjustment procedure called for in the STC instructions.
The local shop worked on it for two - three weeks. The kit also involves installing pumps, switches to operate the pumps from inside the cockpit and also gauges (which surprise surprise don't work worth a damn). Lights need to be moved and rewired, the tips painted, etc. So a good solid 2-3 weeks worth of work.
When the work was completed I got the call and excitedly headed on over. I inspected the work and it all looked good. "So did you adjust the stall warning vane?" I asked. The mechanic looked at me blankly. So I suggested we have a look at the stall warning adjustment procedure because I'm not sure I wanted to hear the stall warning going off on every take off and landing. So we looked through it...and discussed how it was going to be done. He said he would need to get someone to fly the plane since he is not a pilot. No problem, I said, I will of course fly the plane. Then he said he will need to have someone fly with me and record the results. No problem again, I said, YOU will fly with me. No, he said, he doesn't like test flights. And, he said, he absolutely detests the 206 because there is no door on the right side and he wouldn't be able to get out easily. At this point I got a little nervous. Why would be have to get out? What does it mean when the A&P doesn't want to fly in the plane he just worked on? I may have said that if he is not prepared to fly with me then I am going to lose confidence in his workmanship and request him to restore the plane to it's original state. I don't recall exactly but I was almost certainly diplomatic. There was some further discussion and then he agreed he would fly with me.
So now that this was decided, we can move on to the actual process itself. It was nothing complicated, it really was just concerned with making sure that the stall warning sounds a few knots above the stall speed for all configurations and at max gross weight. I forget how much about the stall speed but it was something like 5 knots I think. For the no flap and full flap configurations and at most forward CG and most aft CG I was to hold level flight then slowly bleed off speed at about 1 knot per second and note when the stall warning went off and then when the wing actually stalled. So a pretty typical stall test but a lot slower with the power reduction than usual. We computed our weight and balance. We filled up as much fuel as we could carry (120 gallons). The two of us up front at this point brought us well in front of the CG front limit. We were both large individuals. He was fat and I'm big boned and muscular and least that is my story and I'm going to stick with it. The fact is though we had a lot of weight up front. Luckily we were not at our gross weight limit. So what to put in the back.... Hmmm.... How about sandbags? Yes, let's put sandbags in the back. So we put in enough 25lb sandbags to bring us up to the new gross weight limit. We check the W&B again and we are close to the front CG limit and at max gross weight. Okay good to go! The A&P rotates the stall warning vane by the suggested amount. If we are lucky, the tests will confirm this new position otherwise we will have to adjust and then repeat.
So up we go. Hmmm, I had to use a lot more back pressure than usual to get off the runway. Maybe my A&P friend is a little heavier than he admitted? I notice he is sweating. He is heavy though and heavy people do sweat more than the usual. Maybe I shouldn't read too much into that? All in all it is just a fleeting concern and I don't think any more of it as we progress to the test area we had decided on.
We set up for the first test. This one is with no flaps. I set up level flight then start reducing power very slowly. Pull back to maintain altitude. Hey, this is kind of fun I was thinking I've never done it this slowly before. Keep decreasing. The stall warning starts to sound. Keep dropping the power slowly. Approaching 5 knots. We stall. But this is not like the usual gentle stall. The plane pitches down abruptly and kind of caught me by surprise. I rationalize it though knowing we are near the front limit. The plane is severely nose heavy and as the wing stops flying I surmise the nose drops rapidly down enough that the rear stabilizer stalls rapidly as well and the front drops even quicker. No worries though I recover the usual way. I have to do this three times. Each one gets more abrupt. Now onto full flaps. We set up for the first one. Reduce power slowly. As expected the stall warning comes on at a lower airspeed. Keep decreased. Then we stall. And boy did we stall. The nose pitch downed rapidly and I mean rapidly and before I could react we were staring directly at the ground. We must have been briefly pointing 80 degrees down from horizontal. I do not recall how much height we lost before recovered but it was considerable. The A&P screamed some string of obscenities that I will not repeat here and insisted that the test was over. I did not disagree. Any more rotational inertia as the nose dropped and I could imagine the plane ending up a$$ backwards! And upside down. Unusual attitude anyone? So what does happen with sandbags moving around the interior as you do these kinds of motions anyway?
We flew back to the airport and I demonstrated quite possibly one of the worst landings I've ever done it was shall we say a firm landing. Firm but safe. Don't you hate it when you have a terrible landing and your pilot buddy says "at least it was safe"? You know they're agreeing that it was a terrible landing.
Yes, as suspected the sandbags had shifted. So some things I learned from that day: Flight testing with moveable weights is not the best idea. Doing stalls with a CG in front of and outside the envelope was quite educational. Stalling at a low altitude in this condition would have been fatal. Stall with a too rearward CG would be even more exciting...
No, I didn't do anything illegal or something like that. Maybe just a little dumb. I will be the first to admit that I've done plenty of dumb things in my life. The plan is as I get older that I will do fewer and fewer stupid things and learn from my mistakes as I go... So far so good.Anyway, enough rambling. This particular episode occurred while I owned a 206. I have to admit this is a plane I loved and I miss it. It was a little slow and expensive to operate fuelwise. The engine maintenance was high (I see a thread in the maintenance section on expensive cylinder work right now... Alex I feel your pain been there done that) but besides that the rest of the airframe was inexpensive to maintain. I could practically go anywhere with that plane and almost carry anything. Please excuse me I'm rambling again.
Back to the story. I decided to get the tip tank modification. Flint Aero tip tanks. The tips add three feet to the wingspan but for that you get an almost 200 lbs of gross weight increase. So even if you're not going to use them for holding extra fuel you get to legally load an extra body on your plane.
Have a look at this article though then come right back
http://www.aviationlawmonitor.com/2010/03/articles/general-aviation/the-trouble-with-tip-tanks/
I read about this before ordering the kit so while I'm sure Flint Aero is not thrilled by this story at least in my case it did not affect my decision to get it anyway. I don't know if the installation procedure changed as a result on that particular accident. Either way the installation procedure calls for a fairly detailed process for adjusting the stall warning after installation. More on that later.
I ordered the kit and arranged to have it installed by a local shop. Before I handed it all over I read the installation instructions intensively and was well aware of this stall warning adjustment procedure called for in the STC instructions.
The local shop worked on it for two - three weeks. The kit also involves installing pumps, switches to operate the pumps from inside the cockpit and also gauges (which surprise surprise don't work worth a damn). Lights need to be moved and rewired, the tips painted, etc. So a good solid 2-3 weeks worth of work.
When the work was completed I got the call and excitedly headed on over. I inspected the work and it all looked good. "So did you adjust the stall warning vane?" I asked. The mechanic looked at me blankly. So I suggested we have a look at the stall warning adjustment procedure because I'm not sure I wanted to hear the stall warning going off on every take off and landing. So we looked through it...and discussed how it was going to be done. He said he would need to get someone to fly the plane since he is not a pilot. No problem, I said, I will of course fly the plane. Then he said he will need to have someone fly with me and record the results. No problem again, I said, YOU will fly with me. No, he said, he doesn't like test flights. And, he said, he absolutely detests the 206 because there is no door on the right side and he wouldn't be able to get out easily.
At this point I got a little nervous. Why would be have to get out? What does it mean when the A&P doesn't want to fly in the plane he just worked on? I may have said that if he is not prepared to fly with me then I am going to lose confidence in his workmanship and request him to restore the plane to it's original state. I don't recall exactly but I was almost certainly diplomatic. There was some further discussion and then he agreed he would fly with me.So now that this was decided, we can move on to the actual process itself. It was nothing complicated, it really was just concerned with making sure that the stall warning sounds a few knots above the stall speed for all configurations and at max gross weight. I forget how much about the stall speed but it was something like 5 knots I think. For the no flap and full flap configurations and at most forward CG and most aft CG I was to hold level flight then slowly bleed off speed at about 1 knot per second and note when the stall warning went off and then when the wing actually stalled. So a pretty typical stall test but a lot slower with the power reduction than usual. We computed our weight and balance. We filled up as much fuel as we could carry (120 gallons). The two of us up front at this point brought us well in front of the CG front limit. We were both large individuals. He was fat and I'm big boned and muscular
and least that is my story and I'm going to stick with it. The fact is though we had a lot of weight up front. Luckily we were not at our gross weight limit. So what to put in the back.... Hmmm.... How about sandbags? Yes, let's put sandbags in the back. So we put in enough 25lb sandbags to bring us up to the new gross weight limit. We check the W&B again and we are close to the front CG limit and at max gross weight. Okay good to go! The A&P rotates the stall warning vane by the suggested amount. If we are lucky, the tests will confirm this new position otherwise we will have to adjust and then repeat.So up we go. Hmmm, I had to use a lot more back pressure than usual to get off the runway. Maybe my A&P friend is a little heavier than he admitted? I notice he is sweating. He is heavy though and heavy people do sweat more than the usual. Maybe I shouldn't read too much into that? All in all it is just a fleeting concern and I don't think any more of it as we progress to the test area we had decided on.
We set up for the first test. This one is with no flaps. I set up level flight then start reducing power very slowly. Pull back to maintain altitude. Hey, this is kind of fun I was thinking I've never done it this slowly before. Keep decreasing. The stall warning starts to sound. Keep dropping the power slowly. Approaching 5 knots. We stall. But this is not like the usual gentle stall. The plane pitches down abruptly and kind of caught me by surprise. I rationalize it though knowing we are near the front limit. The plane is severely nose heavy and as the wing stops flying I surmise the nose drops rapidly down enough that the rear stabilizer stalls rapidly as well and the front drops even quicker. No worries though I recover the usual way. I have to do this three times. Each one gets more abrupt. Now onto full flaps. We set up for the first one. Reduce power slowly. As expected the stall warning comes on at a lower airspeed. Keep decreased. Then we stall. And boy did we stall. The nose pitch downed rapidly and I mean rapidly and before I could react we were staring directly at the ground. We must have been briefly pointing 80 degrees down from horizontal. I do not recall how much height we lost before recovered but it was considerable. The A&P screamed some string of obscenities that I will not repeat here and insisted that the test was over. I did not disagree. Any more rotational inertia as the nose dropped and I could imagine the plane ending up a$$ backwards! And upside down. Unusual attitude anyone? So what does happen with sandbags moving around the interior as you do these kinds of motions anyway?
We flew back to the airport and I demonstrated quite possibly one of the worst landings I've ever done it was shall we say a firm landing. Firm but safe. Don't you hate it when you have a terrible landing and your pilot buddy says "at least it was safe"? You know they're agreeing that it was a terrible landing.
Yes, as suspected the sandbags had shifted. So some things I learned from that day: Flight testing with moveable weights is not the best idea. Doing stalls with a CG in front of and outside the envelope was quite educational. Stalling at a low altitude in this condition would have been fatal. Stall with a too rearward CG would be even more exciting...
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