my hot spot is now two years old and has approx 100 flights on it. as i mentioned in a previous post, it was the 10th flight, we heared a high frequency whine because of a failure of the bonding joint near the main gear openings.

IMHO we all should do thoroughly preflight checks (as it is a must for all planes) and in case rebond these joint. this would eliminate the initial cause for delaminating the fuse.

we use turbines from 85N to 130N.

this hot spot was one of the first that has been sold (by peter liebetrau). it has gear door for the steering wheel, but no gear doors for the mains.

our second hot spot is 5 months old (maybe the graupner hot spot comes from another source, manufacturer?) with 50 flights on it. it has gear doors for all wheels. no delaminating tendencies occured till now.

mec


btw: two weeks ago i saw the longest (involuntary) hover of a turbine aircraft (our second hot spot). pilot ernst started with a rolling circle, however and unfortunately too slow. in the inverted flight passage the HS suddenly snaped to a hover position. i estimated it was 200/300 meters away, therefore it was difficult to gain controll over the plane again. the HS hovered at full power, 30 meters above ground. it took 10! seconds till the HS slowly turned to an inverted flight position. with full down elevator ernst seemed to gain control over the plane again. but suddenly the HS stood again vertical loosing altitude more and more. this took again 10 seconds. 10 meters above the ground i advised ernst to shut off the engine. in inverted flight position our HS kissed the earth. it is still repairable.
the damage done is a delamination of the rear fuselage. and it showes bonding techniques of not the best quality (however good enough for safe flights if checked from time to time).