The maiden flight was happily uneventful. No significant trim changes were needed and the control throws, although not optimal, were comfortable. There was no trace of the famed 'Kwik-Fli Dance' and the handling was pretty much as expected. I did though reach the end stop of the elevator travel on flairing out for landing, so the elevator throw was increased slightly for subsequent flights. It is possible that the cg could come back a bit further too, but I'm happy with it as it is for now.
The only problem to emerge on these early flights concerned the nosewheel retract. Although it seemed to retract okay along with the main gear, it had a habit of coming back down again. There was no sign of any mechanical obstacle so my thoughts turned to the electrical side of the operation. I believe that these electric retracts (from HobbyKing) don't use limit switches to detect when the leg has reached the end of its travel. Instead I suspect that they rely on detecting the surge in current when the motor stalls. The maingear acts a bit faster than the noseleg so I wondered whether the surge in current accompanying the arrival of the maingear against their endstops was causing enough of a voltage drop to confuse the nose unit.
The retracts are powered by a separate uBEC of nominally 5a capacity, although looking at how skinny the wires are, I've always been a bit sceptical. Anyway, to eliminate this effect, the nose retract was plugged into a separate receiver channel so that, although it still operates from the same switch as the mains, it can be delayed by a couple of seconds so that it can then have the power supply all to itself after the mains have done their thing. Since making this change, the gear has operated faultlessly.
I've now chalked up 9 flights with the Kwik-Fli and have got it pretty much dialled in to my liking. I look forward to a long and rewarding relationship!
This will probably be the last diary entry but if/when I get some airborne pictures and/or video, I will add them to the site, so keep an eye on the 'Latest News' page.
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