>>...That's all I have to say about that!"...<<
The carb rubbers aren't supposed to be prone to splitting in cases where the
Rotax airbox has been fitted. So it would be useful for you to say and us to
know whether there were other factors at play.
e.g. fuel type, starting problems (i.e. severe vibration at sometime during
the running cycle), over-tightened carb. clips on the rubber, pre-stressing
of the rubber due to the way the airbox had been tightened down, long
flights at 17,000' (!) ETC.
Otherwise, I guess "...you never know what you're going to get.....", to
also quote FG.
Duncan mcf.
----- Original Message -----
From: "Dave Anderson" <dja767@charter.net>
Subject: Europa-List: Engine failure test for glider wings
>
> Well, it has happened. The airplane has itself demonstrated its capability
for safety by having an engine failure - a slow motion failure. I was
climbing out on the usual profile that provides an easy glide back to the
departure airport, when I heard a sound change. It was enough to look over
at the manifold pressure gauge to see 30 inches, when it is normally 36
inches in the cruise climb. I throttled back and then increased power to
confirm the 30 inches was not a hallucination. I checked the fuel flow to
see if there might be some sort of fuel leak - a hazardous condition to be
sure. The fuel flow was normal, so I throttled back to idle and returned to
the airport. I considered shutting down and feathering, but it was running
OK at idle, so I didn't. The airplane arrived over the field at 3500 agl. A
circle followed with full speed brakes, with a high downwind leg. On
downwind, the engine started to vibrate in a quite pronounced manner, so
with the field made, I shut it !
> down , leaving it to windmill. The vibration stopped as soon as I turned
off the ignition, throttle at idle.
>
> The airplane lands the same way regardless of the power - engine at idle
or shut down. The landing was normal and I just took the high speed exit,
coasting to a stop. By that time, the airport people were out there with
their trucks and flashing lights (un-invited). A brief look over the
airplane showed nothing obvious and a peek in the engine cowl showed nothing
obvious either. I tried to restart, but it would not start so it was towed
to the hangar (by my Dad, who had just arrived in his airplane).
>
> The problem turned out to be a very simple one - yet a show stopper. The
engine has two carburetors which are held to the intake manifold via rubber
flanges. It is really quite a Mickey mouse design that I will be doing
something about in the future - a back-up to keep this from resulting in a
non running - or rough running engine. The rubber flange on the left side of
the engine cracked and split 180 degrees, causing the carburetor to separate
enough from the intake to let in enough air to essentially kill the two
cylinders on the port side of the engine. The fix would take about 10
minutes, if I had the $75 part that has already been ordered. The glider
wings paid off making this thing a very easy and almost relaxing event. The
only hiccup was a Cessna taking the runway when I was abeam the numbers on
downwind announcing what was going on. Some people's kids???
>
>
> To quote Forrest Gump "That's all I have to say about that!"
>
>
> Dave
> A227
> mini U2
> 215 hours TT
>
> I'll probably attach the picture of the flange to the Mini U2 web
site.....
>
>
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