Hi Bob,
Since you know all about my "Flying for Fun" accident already, just a
word of WARNING for others reading this thread.
Don't try closing the gills if you fly an NSI Subaru in a Europa. This
PFA "Approved" installation, even with the standard gills the cooling to
the alternator is wholly inadequate and can kill you. This has now fried
2 alternator bearings out of 10 examples in the U.K. I can't find any
U.S examples of such an incident so it looks like a thoroughly home
grown U.K. installation problem.
The alternator seizure would be only a minor inconvenience were it not
for the fact that the dual drive belts as "Approved" then fill the
cockpit with thick smoke before stopping the engine via the braking
effect on the crankshaft drive pulley and the "Approved" propeller then
goes in to full disk drag freewheeling mode providing an earlier
opportunity for a forced landing than you ever bargained for with a
descent deck angle of about 20 degrees and rate of 1700ft/min and with
the all flying"now no longer flying" tailplane allowing you to slap the
stick from stop to stop on the way down as you relearn how to fly the
crippled airframe. All this of course negating any amount of practice
forced landings you were forced to do before being allowed to test fly
the creation yourself and which were so misrepresentative as to have
best been avoided completely !!!!!!!!!!!!!!!!!!!
Been there done that got the T-shirt just like Bill Wynne who had it
happen first but sadly his incident was never subsequently properly
investigated. It will be now though my wreckage is with the AAIB at
Farnborough.
I am still trying to find out if "Approved" for regulatory end users
means anything other than you are "Approved" to go and be our
installation test pilot with a passenger, oh and in case you survive
please report any testing we might have overlooked !!!!!!!!!!!!!
Despite the direct question having been twice posed to the PFA, by me
and the AAIB so far no cigar!!!!!!!!!!!
Ironically, I just applied for the PFA airworthiness engineer job, which
I thought might have even come about because of our near death
experience. I just received a response having heard nothing for a
fortnight as follows;
" Unfortunately you were not short listed for the initial interviews".
That is despite going and asking if I would be wasting my time preparing
a C.V. before hand!
Incedently our Europa callsign was G-BWCV abbreviated to 'CV. Obviously
our recent ridiculous incident was not deemed the right sort of 'CV for
that particular job.
So look outl for the AAIB report coming out soon if you realy want a
case study in how not to do it!!!!!
If anybody thought "Approved" in the regulatory end user context was a
verb implying knowledge or understanding and testing to a standard at
least minimally fit for purpose like I did, think again.
Like most things these days you end up having to do other peoples jobs
for them whilst in the case of the regulators they tie both hands behind
your back when you try to do your own.
Regards
Gary McKirdy
From: R.C.Harrison
To: europa-list@matronics.com
Sent: Wednesday, November 15, 2006 11:43 AM
Subject: RE: Europa-List: Oil cooler thermostat
Hi! Nigel/all
My two pennyworth .....I also tried a cowl exit flap but not to close
off. My Jabiru cooling system of course was ALL air cooled and the
theory ventured by the Jab dealer and Factory was to extend it into the
air stream and create a low pressure area aft of the cooling exit to
suck out the hot air..... needless to say it made no improvement
whatever. However what I did find was that it was important to maintain
top cowl pressure high to promote the mass down flow of air past the
engine, I even collected my cabin heating air(when not being used for
purpose) and dumped it in the cowl top which also assisted. Since all
the high pressure oil cooling air was directed under the sump cooling
fins(Rotax oil and water cooling likewise) to leave it "floating" in the
lower cowl restrained the downward flow of engine cooling air.
You may ask why am I "rabbitting on" about damn Jabiru's ?.... so to
my question:-
What purpose do the Europa "Gills" serve?
Has anyone flown with them blocked off to check the effects?
As it happens, against most advice, I have decided to fit an
intercooler on my 914 Turbo which of course has a huge discharge of warm
air mostly into the top cowling and I'm not sure it's the right
philosophy to let it exit out the "gills", with my Jabiru experiences
I'm suggesting that to increase the down flow of air, even with water
and oil cooling on the engine, it would be best maintaining the top cowl
pressure.
I never had any top cowl exits on my Jabiru set up ...all air was
discharged out the lower cowl exit plus the lower cowl was "jacked" off
the fuselage by approx 1" increasing the discharge annulus considerably.
Any help with these questions would be gratefully received.
I also would have liked to have the Rotax oil flow to its cooler
selectable and/or meterable which I achieved on the Jabiru by a hand
control valve operated from the P1 Position allowing most flying to be
accomplished without the cooler being in circuit. The resultant warm air
(even with no oil circulating though the cooler) was a primary source
of cabin heat and with the oil cooler in full flow I could fry the
passenger, I get the feeling that a number of Europa Rotax owners would
dearly like such a facility !
Regards
Bob Harrison G-PTAG (Still prepared to learn!)
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of nigel
charles
Sent: 15 November 2006 09:38
To: europa-list@matronics.com
Subject: RE: Europa-List: Oil cooler thermostat
<nwcmc@tiscali.co.uk>
>It is best to place a flap at the exit of the cowl/radiator duct.
Placing an obstruction in the front destroys dynamic pressure. An we
need to recover as much pressure as we can to persuade the air to flow
across the rad core.<
For what its worth I tried a cooler flap at the rear of the radiators.
With it fully closed it cut off nearly all the airflow and it made
little difference to the CHT and oil temperatures.
When I was at Vichy this year I met one of our French owners (sorry I
forgot his name). He has a very clever inlet cowl flap. It is part of
the lower cowl in front of the radiators and has a hinge at the rear
of
it. In very hot weather it is lowered below the normal cowl allowing
more cooling air in. In cold weather it is raised impeding airflow to
the radiators. This is all controlled from the cockpit so that
inflight
adjustments can be made. From what he told me it works very well.
I appreciate that normally control of cooling air is best done at the
outlet but in this case it seems it is better to use the inlet.
Nigel Charles
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