Would you fly this Aircraft?

"John Gaquin" wrote in message
...

Pointless question. Insufficient data for any kind of decision.
Presumably, you'd preflight the aircraft anyway, which obviates your above
question.

Not really. For me, the question is do I bother making the trip to the
airport, or do I wait for someone else to be the "canary in a cage". I've
also got a slightly nervous a passenger to consider - last thing I want is
an engine fire with a nervous passenger sitting right next to it.

The crux of the question really is "if the licenced and qualified engineer -
who would get paid for fixing the problem if there was a problem - says that
it's OK, does one trust that? As a pilot I won't be able to see where the
leak is coming from without removing the cowling - which is engineer only
territory.

Part 2 of the question is "why would full tanks cause this - why wouldn't
the excess get squeezed out the tank vents"?

The crux of the question really is "if the licenced and qualified engineer -
who would get paid for fixing the problem if there was a problem - says that
it's OK, does one trust that?

Do you trust the FBO? Why or why not? Follow the money.

Part 2 of the question is "why would full tanks cause this - why wouldn't
the excess get squeezed out the tank vents"?

That by itself, and no explanation from the "licensed and qualified
engineer" as to what caused it, would cause me to let somebody else be
the guinea pig.

Jose
--
Nothing takes longer than a shortcut.
for Email, make the obvious change in the address.

"Jose" wrote in message
. net...

The crux of the question really is "if the licenced and qualified
engineer -
who would get paid for fixing the problem if there was a problem - says
that
it's OK, does one trust that?

Do you trust the FBO? Why or why not? Follow the money.

From a FBO position it's really not a "money thing" (I used to run the
outfit, and I know that that doesn't enter into it) - as far as trusting
engineers go, well, it's been my experience that they know their stuff
pretty well, but like all of us they make mistakes - and I've been around
the game long enough to have experienced many situations where the aircraft
has gone into the shop with 1 fault, and come out with 2 new ones - so I
guess you could say that a "healthy dose of suspicion goes a long way in
this business".

The first 100 hours on a brand new airplane, the first hour
after an inspection and the first 5 hours after maintenance
are times to be very extra cautious about the airplane, are
all the spark plugs properly torqued? Are the fuel lines
secure? Are the control cables routed and safetied?

Things that have happen to me personally on such airplanes,
just a sample.
Exhaust manifold broke the welds on one bank, this let the
exhaust drop into the air blast where it caused a lot of
vibration and would be blown back up, this cycle repeated
about 2 seconds. I was in a new airplane, carrying my first
passenger and about 10 miles from a landing. Almost 40 years
ago.
Test flying a Beech Duke that had just finished the annual
inspection, at about 12,000 feet the clamp that secures the
exhaust pipe to the turbocharger broke, which allowed the
hot exhaust gas to melt a very big hole in the cowling. All
I saw was a small spot on top of the left engine change
color, like the paint was a different shade of tan. Shut
down the left engine and returned for landing. The shop gad
wanted me to test fly it the night before, which wouldn't
have let me see the paint change color. A 1/2 inch fuel
line (stainless steel) was very close to the hot blast.

Tools left in the airplane become my property.



--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"C J Southern" wrote in message
...
|
| "Jose" wrote in message
| . net...
|
| The crux of the question really is "if the licenced
and qualified
| engineer -
| who would get paid for fixing the problem if there was
a problem - says
| that
| it's OK, does one trust that?
|
| Do you trust the FBO? Why or why not? Follow the
money.
|
| From a FBO position it's really not a "money thing" (I
used to run the
| outfit, and I know that that doesn't enter into it) - as
far as trusting
| engineers go, well, it's been my experience that they know
their stuff
| pretty well, but like all of us they make mistakes - and
I've been around
| the game long enough to have experienced many situations
where the aircraft
| has gone into the shop with 1 fault, and come out with 2
new ones - so I
| guess you could say that a "healthy dose of suspicion goes
a long way in
| this business".
|
|
|

#2 Full tanks increase fuel pressure, a poor seal on the
carb float needle valve will leak and fill the bowl, which
then over-flows. The tanks have about 10-15% free space
even when full to allow parking on non-level surfaces before
the tank vents begin to drain.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"C J Southern" wrote in message
...
|
| "John Gaquin" wrote in message
| ...
|
| Pointless question. Insufficient data for any kind of
decision.
| Presumably, you'd preflight the aircraft anyway, which
obviates your above
| question.
|
| Not really. For me, the question is do I bother making the
trip to the
| airport, or do I wait for someone else to be the "canary
in a cage". I've
| also got a slightly nervous a passenger to consider - last
thing I want is
| an engine fire with a nervous passenger sitting right next
to it.
|
| The crux of the question really is "if the licenced and
qualified engineer -
| who would get paid for fixing the problem if there was a
problem - says that
| it's OK, does one trust that? As a pilot I won't be able
to see where the
| leak is coming from without removing the cowling - which
is engineer only
| territory.
|
| Part 2 of the question is "why would full tanks cause
this - why wouldn't
| the excess get squeezed out the tank vents"?
|
|
|

"Jim Macklin" wrote in message
news:II7Tf.118045$QW2.26850@dukeread08...
#2 Full tanks increase fuel pressure, a poor seal on the
carb float needle valve will leak and fill the bowl, which
then over-flows. The tanks have about 10-15% free space
even when full to allow parking on non-level surfaces before
the tank vents begin to drain.

Hold the phone, here.

You mean fuel tanks can build up pressure with functioning vent lines?
Hummm.

If it is a bad (plugged) vent, then I'm not going to fly it until *that*
detail is fixed.
--
Jim in NC

Fuel has weight, a little less than .5 pounds per foot of
distance. A high wing Cessna has about 3-4 feet between the
fuel tank and the carb float. The float in the bowl is
raised by the liquid fuel in the bowl and by a lever,
presses the needle valve closed, stopping the flow of fuel
by gravity.

If the needle valve is leaking, there are two problems,
during engine operation, the fuel level will be too high
making the mixture too rich, although this can be manually
leaned, but the bowl may still fill to over-flow and this
will cause a lose of fuel which can result in an fuel
starvation accident.

When parked, it can cause a fire hazard and certainly waste
expensive fuel.

For a science experiment, take a straw and place it in a
glass of water and place your finger over the end of the
straw. When you lift the straw, the water won't flow out of
the straw because it isn't vented, but the pressure of the
water is due to the weight of the water caused by gravity.

Low wing airplanes and some high wing airplanes with carbs
also have fuel pumps, all fuel injected engines have pumps
because gravity is not powerful enough to operate the
injection system.


--
James H. Macklin
ATP,CFI,A&P

Just to explain this, ATP is Airline Transport Pilot
CFI, I have Gold Seal Airplane SMEL and Instrument
A&P Airframe and Powerplant mechanic



--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"Morgans" wrote in message
...
|
| "Jim Macklin" wrote
in message
| news:II7Tf.118045$QW2.26850@dukeread08...
| #2 Full tanks increase fuel pressure, a poor seal on
the
| carb float needle valve will leak and fill the bowl,
which
| then over-flows. The tanks have about 10-15% free space
| even when full to allow parking on non-level surfaces
before
| the tank vents begin to drain.
|
| Hold the phone, here.
|
| You mean fuel tanks can build up pressure with functioning
vent lines?
| Hummm.
|
| If it is a bad (plugged) vent, then I'm not going to fly
it until *that*
| detail is fixed.
| --
| Jim in NC
|

"Jim Macklin" wrote

Fuel has weight, a little less than .5 pounds per foot of
distance. A high wing Cessna has about 3-4 feet between the
fuel tank and the carb float. The float in the bowl is
raised by the liquid fuel in the bowl and by a lever,
presses the needle valve closed, stopping the flow of fuel
by gravity.

I know how all of that stuff works, but using you figure, it the tank is 6"
overfilled, it is going to have an increase of pressure of 1/4 psi?

If that puppy is leaking because of that, I would still park it, wouldn't
you?

Stuff like that can get worse, and cause all kinds of problems that I would
rather deal with on the ground.
--
Jim in NC

Certainly, but sometime valves will seal at one pressure and
leak at very little more. The point is, no fuel leaks are
allowed. I've seen Piper PA 28 with fuel stains on the
selector valve inside the cockpit, being flown. The owner
was telling students it was OK.

I've seen airplanes with fuel stains at the wing root, on
the belly and just about everywhere, except maybe the top of
the tail. Fuel isn't supposed to leak. Even if the plane
is just over-filled, the free space in the tank should allow
for expansion if the plane is parked on level ground. Some
airplanes will transfer fuel from one wing to the other if
not parked on "level" ground.

But if the tank was empty and the valve had a full pound
less pressure and did not leak and did leak when just fueled
to full, it isn't an over-filled condition just the weight
of the normal fuel and a bad valve seat.


--
James H. Macklin
ATP,CFI,A&P

"Morgans" wrote in message
...
|
| "Jim Macklin" wrote
|
| Fuel has weight, a little less than .5 pounds per foot
of
| distance. A high wing Cessna has about 3-4 feet between
the
| fuel tank and the carb float. The float in the bowl is
| raised by the liquid fuel in the bowl and by a lever,
| presses the needle valve closed, stopping the flow of
fuel
| by gravity.
|
| I know how all of that stuff works, but using you figure,
it the tank is 6"
| overfilled, it is going to have an increase of pressure of
1/4 psi?
|
| If that puppy is leaking because of that, I would still
park it, wouldn't
| you?
|
| Stuff like that can get worse, and cause all kinds of
problems that I would
| rather deal with on the ground.
| --
| Jim in NC
|

"Jim Macklin" wrote in message
news:C18Tf.118046$QW2.74826@dukeread08...

Fuel has weight, a little less than .5 pounds per foot of
distance. A high wing Cessna has about 3-4 feet between the
fuel tank and the carb float. The float in the bowl is
raised by the liquid fuel in the bowl and by a lever,
presses the needle valve closed, stopping the flow of fuel
by gravity.

In this case it's a low-wing twin - the engines are (probably) slightly
above the tanks - very little in it either way.