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Dragonfly7861
15-12-13, 11:01 AM
I'm the proud owner of a FlyLight Dragonfly single-seat trike, one of about 5 I know of in Australia. Superb British product. I now have 56 hours on mine, and have had only two maintenance issues.

The first was a tendency for the plug lead to drop off, resulting in an increase in determination to find a thermal in order to get home. I have since placed a cable tie over the plug lead to prevent a recurrence, inspect it before each launch, and have had no further trouble. I plan to replace the cable tie at 25 hourly intervals to make sure there is no heat deterioration.

The second issue was heat damage to the nose-wheel assembly. I had a flat nose-wheel and on disassembly to repair the tube I found that the plastic wheel hub appeared to be damaged, leading to tube damage. When I split the hub, it was apparent that I had used the front brake excessively at some point, and the plastic hub had partially melted where the brake drum fixes to it. On reflection, I have recently had some long taxi routes due to the seasonal Easterlies, and I think I have been guilty of dragging the brake to keep speed down - a cardinal sin for which my instructors of the past would have roundly bolloxed me (I'm military trained - you know, toilet trained using a flame thrower).

A quick call to the Australian distributor, and in no time a new tube, tyre and wheel hub arrived in the post. Happily airborne again, and very happy with the parts supply and promptness. So, don't drag your Dragonfly brakes on taxi, and in your after-flight inspections, run your eye over the plastic nose wheel hub looking for signs of heat damage. Purely my fault, but something worth being aware of with this little gem of a trike.

D-Flyer
15-12-13, 13:42 PM
Couldn't agree more - we love our yellow DF, it's so much fun to fly! Never had the problem with brakes, though - we went without them :-). Tread wear on my trainers has only marginally increased.....

Dragonfly7861
25-12-13, 11:26 AM
I have stopped using them, other than for just pulling up to a complete stop. Which is of course the right way to treat aircraft brakes. If you need them, you're not doing it right!
Isn't the DF just the greatest fun? Bit frustrated here at the moment, we have had a most un-seasonal run of atrocious weather - low cloud, rain, cold. Summer in Sydney!

Paul Dewhurst
25-12-13, 19:47 PM
I have stopped using them, other than for just pulling up to a complete stop. Which is of course the right way to treat aircraft brakes. If you need them, you're not doing it right!
Isn't the DF just the greatest fun? Bit frustrated here at the moment, we have had a most un-seasonal run of atrocious weather - low cloud, rain, cold. Summer in Sydney!

We ( Flylight) have a disc brake system we have been experimenting with and just going into production.

Mick Broom who has retired from being a development engineer, couldn't help himself and has been pimping his Dragonlite chaser with an eye on son David flying it in competition. He has fitted disc brakes to all three wheels, and made leading arm rising rate front suspension too. It was on the BMAA competition / SSDR stand at the NEC. It should stop like a limpet immediately after touchdown! In actual fact it has four disc brakes fitted - can you guess what the fourth does?

thats part of the fun of SSDR - retired engineers can be not quite so retired and play with them to their own particular twisted satisfaction:) being a long time motorcycle development engineer he has a road trike projects under his belt. He is convinced that two wheels at the front is the best layout and is threatening to make a flying trike like that - even got a few drawings done!

Paul

Russ_H
25-12-13, 20:24 PM
The prop?, if so why?, is engine off gliding part of the comps?

P.S. he is dead right about 2 wheels at the front being better

Paul Dewhurst
25-12-13, 21:49 PM
The prop?, if so why?, is engine off gliding part of the comps?

P.S. he is dead right about 2 wheels at the front being better

yes! - the Polini has a centrifugal clutch, and prop free wheeling makes much more drag than a stationary one - so a prop brake helps for gliding. And yes limited fuel duration is a part of the international comps, and occasionally used at nationals. Even on a day when lift is weak, gains can be had by using what would normally be level flight power for no lift, taking any lift up high, and then turning off and gliding down at reduced sink rate through the thermal column uses less fuel than a continuous low power setting.

Paul

Russ_H
25-12-13, 22:37 PM
Makes good sense then with the clutch, as you say Paul, windmilling props make great airbrakes (the BMW in my Skyranger had a clutch and shutting off over the hedge, even a ham fisted pilot like myself could notice the braking effect from the freewheeling prop)