Listers,
This is only for those interested in the trials of the early testing phase of a very amateur built RV. I have about 10.5 hours on my 6 now. There are several problems.
I have previously described a carburator problem that caused a hesitation when increasing power from around 1200 or 1300 rpm. I expect a new carb from Aero Sport Power on Monday.
I have a heavy left wing. I have squeezed and squeezed on the right aileron. Well, the aileron is ugly now but there is still an imbalance. The stiffeners prevented squeezing as much where the stiffeners are so my aileron has a scalloped appearance. I did not build the ailerons on this QB kit so am not sure, but it appears the stiffeners extend back further than plans. This would seem to be good for everything but trying to get an even squeeze. I am considering building a new aileron. I am not sure of the cause of this heavy wing. The incidence could be off of course. The left wingtip came out with the trailing edge out of line above the aileron trailing edge. That could be it also. It is interesting that when the ailerons are held in what appears to be the neutral position in flight there is no wing heaviness. The ailerons seem to want to go out of neutral. The effect increases with speed. There is no noticable wing heaviness at climb speeds. I now wish I would have put a wedge under the right aileron but I had read about how powerful the squeezing is so tried it for too long. The wing heaviness I have is trimmable with the spring aileron trim system but I don't like it.
My alternator pully rubs on the cowl. I guess this is a common problem but it seems pretty bad on mine. I have the cowl mounted as far forward as I think possible. There is minimum clearance between the spinner and cowl and I can just barely get the cowl on. The alternator is a B&C 60 amp with a 36.5 inch belt. This is a small alternator. Through experimentation I have found this is the shortest belt that can really work so I am unable to get the alternator to ride any higher. On the first few flights this problem seemed minor as there was only a small groove but after the groove got large enough it got worse as it now allows the belt itself to rub. This happens at only 2 g's and is accompanied by smells of burning rubber and all kinds of rubber soot inside the cowl. How can you fly this airplane and limit it to 2 g's? I will add a bubble for the pulley. It will be a further demonstration of my mastery of the art of fiberglass.
Yesterday about 6 rivets broke and or pulled out of the lower rear cowl hinge attachment adjacent to the cooling air exit. This is disappointing to me for an area that is plans built, after only 10 hours. I have heard many warnings about the stock cowl attachment method and did go with #8 screws next to the spinner and on the rear upper cowl but used the hinges at the side seam and all four aft lower cowl sections. There must be a lot of pressure here. One lister has advised me to open up the air exit a little. My present plan is to drill out all the hinge sections and go with screws here too.
Well, those are my biggest problems. The worst of it is it is painfull to take the plane out of flying status because it is such a blast to fly. I flew alongside a Mooney 201 yesterday at 16 inches and 2100 rpm. I'm sure he could fly a lot faster but not as fast as me.
The good part of the testing is that my high temps from the first few flights seem to be gone. For most of my flight yesterday (around 74 degrees at 7500 feet) the CHT's were running around 410 and oil temps around 190. When I was not running high power, which I am still trying to do most of the time, the temps would go way down.
I still haven't been able to do performance testing or much in the way of aerobatics, because of the problems, but I have always found that in excess of 1,000 fpm is available (at density altitudes of up to 14,500) and 165 knots are more is also always available.
I am finding that my speed, which is till quite good, is limited by the pitch on my Sensenich 72FM8. This prop is supposed to have an 83 inch pitch but that is not enough for my airplane. I can not use full throttle without redlining on RPM until up around 12,000 feet. Consequently my maximum cruise speed occurs much higher than the normal 8,000 or 9,000 feet. I did get a full throttle cruise TAS of 175 knots the other day up high (I think it was 12,500), verified with two way GPS, so I don't feel like I can gripe much. I have no way of accurately determining power percentage but that has to be well below 75% power.
Do not archive due to length
Larry Pardue Carlsbad, NM
RV-6 N441LP 10.5 Hours