Hi Troy / Graham / All,
The ''whistle'' comes from the airflow over the slots in the rear fuselage
where the tailplane trim tab ''Tee'' bar exits.
During the flight testing of G-YURO and G-ELSA , we experimented with clos
ing up all the gaps etc to see if there was any worth in doing just that,
all that happened with the sealing of the tee bar slot was that the noise
went.
On G-ELSA, I had to replace the tailplane pitch pushrod, which meant cutti
ng a 2 1/2'' hole in the lower sternpost to withdraw it aft, the whistle
went, when I eventually plugged the hole, the whistle returned.
I guess it is like playing a flute [ which I have never done] or blowing
over the neck of a beer bottle [ which I have !]
Cheers,
Nev.
-----Original Message-----
From: GRAHAM SINGLETON <grahamsingleton@btinternet.com>
Sent: Tue, 31 Aug 2010 12:12
Subject: Re: Europa-List: Europa Sounds in Flight
Troy
Many of us have heard it, that sound has been there since day 1. My EZ use
d to make a similar sound if I forgot to put the covers on the main spar
access hole, it's probably a cavity resonating, maybe the aileron push ro
d tunnel? Tends to happen when the airplane rolls,
Graham
From: Troy Maynor <wingnut54@charter.net>
Sent: Monday, 30 August, 2010 2:04:20
Subject: Europa-List: Europa Sounds in Flight
Hi All,
Long ago in the original Europa factory video, there is a segment where th
e two factory planes do a low pass. When they pull up and bank you can hea
r a whirring sound or a cry similar to the sound a bird or something. I kn
ow this may sound ridiculous but maybe some of you have heard it yourself.
I watched a short clip of my Europa do a fast low pass last Thursday and
heard it coming from mine also. You can't detect anything inside the cock
pit that I'm aware of, and I'm certain I didn't go supersonic. The first
time I flew over my brothers home a couple months ago his wife later said
(with an unknowing worried look on her face) that she had heard a screaki
ng sound. At the time I didn't lend much creedance to her comment. It happ
ened again while flying over another friends house, so now I am curious.
Has anyone else experienced this? Is it coming from the engine? Prop? Som
ewhere along the airframe? I don't think it's anything to worry about but
I just want to know if others have heard this. On all occasions, the air
craft was in a banking climb. It actually sounded pretty cool. Just wonder
ing....
Troy Maynor
Monowheel Classic UK120
47 fun hours so far!
htt-->
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