Primarily for general aviation discussion, but other aviation topics are also welcome.
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By Dodo
#1787499
Just an update.

We have had a good look at the airframe, and nothing seems to be moving, loose, or flapping. We have had the mufflers off and found all ok. We have had done extensive ground running with no recurrence of noise on the ground.

I did a long flight a couple of days ago with an instructor friend who had a couple of hundred hours instructing in Bolkow Juniors back in the day and no noise was heard. While he was flying I had a good chance to stick my ear near the tacho. That sounded OK. And I listened to the Gyro instruments. The AI has noisy bearings, but different noise. The DI sounded fine.

I flew it again yesterday, solo, for an hour with no noises.

If it comes back, I will have to think again.

Thanks everyone.
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By Rob L
#1787525
Dodo wrote:Just an update.

We have had a good look at the airframe, and nothing seems to be moving, loose, or flapping. We have had the mufflers off and found all ok. We have had done extensive ground running with no recurrence of noise on the ground.

I did a long flight a couple of days ago with an instructor friend who had a couple of hundred hours instructing in Bolkow Juniors back in the day and no noise was heard. While he was flying I had a good chance to stick my ear near the tacho. That sounded OK. And I listened to the Gyro instruments. The AI has noisy bearings, but different noise. The DI sounded fine.

I flew it again yesterday, solo, for an hour with no noises.

If it comes back, I will have to think again.

Thanks everyone.


Thanks for keeping us updated; hopefully it was "just one of those things". Full marks for investigating as best you could :thumleft:
Hopefully it was something simple like a seat belt flapping in the breeze.
By PeteM
#1787900
Interesting. My odd noises have had an explanation - although getting to it was not straight forward!

At 115kt one of my old aircraft would fart! The rubbers on the rear of the canopy would be flipped up by the. presumably higher cockpit pressure, or lower pressure behind the canopy and emit a loud fart. Pretty effective as a speed warning once you knew what it was. The amount of cabin air would change the speed slightly!

Equally on another, rather older machine, a persistent hum, which had been around a maybe an hour, suddenly turned into an a mighty flapping and thumping, as the rubber on the inside of the wing root fairing on an Auster tore free, and tried to make a break for freedom. A prompt landing and work with a penknife sorted that one!