Raimo,
Could have been a missing or loose propeller spinner hub bolt?
Angus Ward,
Tim=99s son
Tim Ward,
12 Waiwetu Street,
Fendalton,
Christchurch 8052
New Zealand
Ph; 03 3515166
Mob; 0210640221
email; ward.t@xtra.co.nz
From: Raimo Toivio
Sent: Sunday, October 02, 2011 8:44 AM
Subject: Europa-List: Heavy In-flight Vibration Riddle
All
I have hope-so a nice riddle for you.
Maybe all the answers are useful =93 let=C2=B4s collect them all:
***
Yesterday I took off from a very remote /small /windy (90 degrees 12
knots and gusting MUCH) grass strip. Soon until well over the ground at
altitude +500 feet with full power and 2nd fuel pump still on and gears
up I felt suddenly let us say medium or more shake and vibration. My
immediate reaction was to go around and land immediately but abandoned
because wind was so furious and I felt I cannot do that (a succesful
landing).
I decided to try to fly to the next possible sensible airfield EFHV
which was 10 minutes apart.
Those minutes were long: I put my prob (Airmaster CS) to manual and
drived it from fine to coarse, tried all the power settings and also a
2nd fuel filter. Finally I noticed that when prop was in a climb mode
(in my case 5400 rpm /Rotax 912S) and MAP around 20 inches I got quite a
comfortable flying mode and I headed straight home. My airspeed was w
that selection about 110 knots but because of a strong headwind GS was
only about 70 knots (wanted to be clearly over the ground at 3000 ft
because it was well over sunset and totally dark, yesterday we got
sunset around 1600 Zulutime and time was well over 1630 when flying).
So, I pushed home one looooong hour. All the aerodynamics were well. I
was a bit worried my engine will separate or so. When trying to push
more pwr it was more vibra and when trying to pull less pwr same. I
Followed a main highway and decided to land there if feeling so. Cars
there with lights are almost like a lighted runway...
Finally landing to the EFTP flawlesly.
***
Today we had a FHGP (Family Hangar Grill Party). I tried to check my
plane as well as I can. I found something. Very small evidence but
something anyway. I tried to fix it and had a test run. I elected to go
to fly =93 hey I am a test pilot who else =93 and She was
better than ever!
I managed to do 2 touches and goes when C172 did one with same runway.
140 knots during downwind makes me always happy.
***
So =93 dear Ladies and Gentlemen =93 what was wrong?
It would be nice and very life-useful to hear your opinions or guesses
what was wrong.
***
The Rules: one single guess per person, please.
The Prize: The Best Guess will get a Very Special Xmas Present from
Finland!
***
I will let you know a solution after a week =93 be patient.
Have a nice weekend and
Cheers, Raimo Toivio
Europa XS Mono OH-XRT #417
Updated flight hours /landings: 258,3
37500 Lempaala
FINLAND
p +358-3-3753 777
f +358-3-3753 100
toivio@fly.to
www.rwm.fi
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