Hi there all !
Talking about compromise, what about drilling a hole in the plug of the
filler as a vent (like the owner of Vega ULM located in our hangar has
done
on his wings). With the sight gauge connected to the cobra. Looks like
so
simple but I can=92t see the inconvenient=85
Max Cointe
F-PMLH Europa_TriGear
Kit #560 912ULS Airmaster 450 hours
<mailto:mcointe@free.fr> mcointe@free.fr
De : owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] De la part de Bud Yerly
Envoy=E9 : mardi 8 janvier 2013 05:20
=C0 : europa-list@matronics.com
Objet : Re: Europa-List: Power loss and Inspecting comments
Paul,
I make sure my drain for the cobra neck is a ways down the tube so the
first
time I know my tank is full (other than my sight gauge) is fuel runs out
the
vent / drain. This keeps the bugs out and the tube clean I guess. I
put
the vent inboard just enough to miss my toes on an overfill.
Airplanes are 20,000 compromises flying in close formation. So we all
have
to put up with something. I have never had a problem with my vent tube
or
drain. But then again I have a trigear and operate off of asphalt. I
too
do not like fumes in the plane, so I make a metal elbows for the filler,
use
lined fuel tube, (R9 style), put drains under the tank bottom
reinforcements, under my cockpit module where my pumps are, under my
seats
where the filters are so I know if I have a leak anywhere, and it all
stays
clean.
My wheel pants are quite low for speed and so I avoid soggy grass
strips.
Those who complain about upper vent vs lower vent are living with other
compromises. I just don't like them up there and because I tend to do a
bit
of spirited flying, fuel comes out of my upper drains if installed and
fuel
stains. They are tough to finish nice also, and the sight gauge vent
tends
to change the fuel level at different speeds. They are also tougher for
the
upholster to finish on the inside.
It is all about compromises and preferences.
Best Regards,
bud
----- Original Message -----
From: Paul McAllister <mailto:paul.the.aviator@gmail.com>
Sent: Sunday, January 06, 2013 12:09 AM
Subject: Re: Europa-List: Power loss and Inspecting comments
Bud,
Thank you for your comments. Well thought out and valuable as always.
I was one of the earlier pioneers of the system to route my filling vent
and
into the top of the cobra inlet. For the fuel tank / system vent I did
something different again.
I adopted the idea that Robin use and placed my vent in the backside of
the
wing root. At the time I thought this was a great idea, but over time
perhaps its only a good idea, maybe not even that. The upside is that
it is
unlikely to be plugged by mud, but there are a number of downsides:
- Once in a great while, if I over fill the tank, it will run out of
this
vent and out of the wing root over the flap. I inspect the flap
regularly to
make sure fuel has not got inside the core and dissolved the foam.
- If I over fill the tank the fumes make there way into the flap drive
slot
during flight.
- I have to take the wing off to inspect the vent which doesn't happen
regularly. There is a slight risk on my area that an insect called a
"Mud
Dauber" can get in there.
So, in conclusion, while these departures from the original design seem
like
a good idea there are often hidden consequences.
Over the years I have become involved in inspecting and technical
counselling for the EAA, and the experience of this community has taught
me
that fuel systems and modifications to them feature high on the list of
accident causes.
Cheers, Paul
On Sat, Jan 5, 2013 at 10:40 PM, Bud Yerly <budyerly@msn.com> wrote:
Jim, and tibits for the rest of us:
After the tire failure and the subsequent off roading mud and dirt
experience while cross country, I commend you for your pursuit of the
problem which cost you much time, and money. You knew you had a mud
plugged
vent, but an experienced guy like you missed the kinked vent line cause.
So
what's a normal guy to do?
I had to ponder that we (really me), are always quick to assume an
engine
related problem is causing the power loss. You told me about finding
the
kink but I still assumed that you had a carb problem. You cleared the
clogged vent, but who would have thought about the rest of the vent
system
and a possible kinked line when the plane has been flying for years. I
am
anal about fuel system install and operation, but once installed, I
rarely
look beyond making sure there is not chaffing or leaks.
Added for all of us:
Recently I just finished an extended annual and another fuel tank
replacement / annual in a couple aircraft that I helped customers build
back
in 2002 and 2004. Interesting to note that on both aircraft, that they
were
past the 5 year hose replacement timeframe (we all dread that). In both
aircraft I found that the vent line was kinked or compromised. In one
of
the aircraft when the upholsterer forced the fabric around the fuel
cover he
had forced the fuel cover over one of the polyurethane vent lines and
over
time the cover pushed on it nearly flat so it barely vented properly,
and on
the other, the vent line was perfect looking, but the hose was horribly
brittle because the vent tube was made from clear Tygon tubing. Tygon
is
supposed to be completely impervious to fuel related problems. Duh,
maybe
not...
In my old Europa Operators Manual there was the requirement to pull the
fuel
bosses off and flush the tank annually, which is quite tough, but never
to
check our vent system, and in the new ops manual, it only indicates to
check
and inspect for leaks. The 5 year recommendation for changing hoses is
still there, but not the vent lines. Vent lines never get checked.
As far as I know, you are the first with an underside vent that ever got
plugged, however, you are the only mono I know of with the vent on the
bottom and operate off of grass a lot. In the trigear the vent on the
bottom is always clean, but your point of the oil overflow on the right
side
of the cowl exit and a centrally located vent will be a potential
problem
for oil, grime and dirt. I'll have to admit I will make sure my annual
checklist is changed to check the vents.
I prefer not to vent out of the top because with the motor glider in
turns
when trying to soar, the fuel sprays out of the vent in right turns. It
also will vent fuel out if overfilled on a hot day in Florida and let
set in
the sun (especially a mono), which of course can ruining the paint.
Inspecting an aircraft is not an exact science. Manufacturers and
regulating agencies give only vague guidance. We are the manufacturer
as
the builder, so we set the guidelines for inspections of our aircraft,
and
if the kit manufacturer gives guidance, we the manufacturer of the
aircraft
should be more specific, not less to include info on our added systems,
changes, modifications, and additional wear areas or time change items
due
to all the above. I'm in the US, and have my A&P use the FAA FAR 43
Appendix D as well as the engine 100 hour checklist and I insist on him
using the Kit Manufacturers guidelines such as the Appendix E of the
build
manual and Section 8 of the Ops manual when inspecting an experimental
aircraft. Now, I have been accused of doing a complete rebuild instead
of
an annual inspection, but I am anal so that is my excuse, but on an
experimental aircraft (especially one I didn't help build or maintain) I
have found that there are many non standard items, routing conflicts
between
wiring, fuel lines, brake lines and control cables, as well as poor
installation of equipment and structural construction mistakes that the
builder and final FAA inspector missed on the initial Airworthiness
Inspection. The FAA actually requires us, as US Experimental Aircraft
Manufacturers, to have established maintenance and operations
procedures.
I am attaching my personal annual inspection checklist out in the open
to
show what we the builder can do to improve the inspections on our
aircraft.
I only just added an item to inspect the fuel vents since you called me
about the problem weeks ago. I developed this checklist long ago,
before
becoming a Europa owner and just tailored it to include items in the
Europa
Section 8 inspection, the FAA and LAA recommended guidelines etc. I am
preparing to submit some of this info in a condensed fashion in an
updated
Tech Support section of Europa's Website as well as some other notes we
all
should know when maintaining the Europa. Now this is my personal
checklist,
not for general dissemination as a Europa Directive, but provided for
others
to see that an annual inspection is not a walk around. But then again,
it
is not an IRAN (Inspect and Repair as Necessary) like the military does
by
completely disassembling every panel, inside and out, instruments,
wings,
engine, etc. and inspect, refurbish, service and repair all the above,
it is
however, more than a quick check for wrinkles in the skin, change the
oil
and sign it off.
Great job of troubleshooting and thanks for the report Jim. Your
findings
and my recent observations have changed my annual checklist for sure...
Regards,
Bud Yerly
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