Flying w/faulty gas gauge

Angus Davis wrote:

Per the FARs, your gauges were functional. The only requirement is that
when the tanks are empty, the gauges read empty.

That's not true. The FARs require that the gauges "show the quantity of fuel
in each tank". If that gauge reads 1/4 tank when the tank is full, it's not
showing the quantity in the tank.

George Patterson
They say nothing's certain except death and taxes. The thing is, death
doesn't get worse every time Congress goes into session.

In article , Yossarian
wrote:

I understand that functional fuel gauges are required equipment for day VFR
flight. Yesterday during my preflight in a 172 I saw that the right gauge
was functioning intermittently--it would show full, flicker down to zero,
bounce around, etc. Tank was visually confirmed full. Mechanic messed
around with it for a while to no effect.

I believe certification only requires that the gauge show empty when
the tank is empty.

Would you fly this airplane?

If you have visually checked the fuel quantity and know approximately
what your fuel burn is, (you do fly by your watch don't you?) you
should be good to go.
I was going to say that my Champ doesn't have a gauge, but then I
remembered there is and I think it is off a Model A Ford. Of course, in
a Cub it is just a wire in a cork sticking up through the cap.

mike regish wrote:

It's only requirement is that it reads empty when the tank is empty.

Nope. The requirement is that the gauge show the quantity of fuel in the tank.

George Patterson
They say nothing's certain except death and taxes. The thing is, death
doesn't get worse every time Congress goes into session.

"mike regish" wrote in message news:R%xtb.161414$275.497496@attbi_s53...
Two watches will do that. Or a double timer like I use.

There are a number of reasons why you might be using fuel FASTER than you
are timing it. Let me tell you a few stories.

A few years ago we got the Navion back from annual. The IA had signed off on it, and
another A&P, Margy, and I put the plane back together. The A&P and I took it up for a
test flight and after immediately opened her up to inspect for leaks and all looked good.
The next morning we take off for Oshkosh with Margy in the left seat. She's negotiating
with Approach for FF and a Class B clearance. I'm looking at the fuel guage and thinking
"I'm pretty sure I topped the thing off, but we're down gas." I tell Margy and I tell I'll keep
an eye on it. As it is, we've got over 80 gallons left on board. The downward trend continues.
Just at this time approach calls back with oru clearance. We're about midway between
two airports, we tell Dulles that we're going to Leesburg, they offer assistance.

Get down on the ground, find a mechanic, find that a fuel line is loose and spraying fuel
all over the inside of the engine compartment. I do a quick calculation and determine that
we have used 20 gallons in a 20 minute flight. That is 60 GPH!

Another long time rec.aviator put his Cardinal down on a road because he ran out of fuel
due to a higher than predicted fuel burn. Was found that his carburator was leaking.

Another rec.aviator ran out of fuel IFR. Nobody yet knows what happened, but he ran
out way ahead of what preflight planning predicted.

****ty as your average light plane fuel guages are, they are NOT superfluous.

"EDR" wrote in message ...

I believe certification only requires that the gauge show empty when
the tank is empty.

You keep saying this, but it's not true.

Of course, in
a Cub it is just a wire in a cork sticking up through the cap.

Works better than a lot of gauges...

EDR wrote:

I believe certification only requires that the gauge show empty when
the tank is empty.

Nope. The gauge must show the quantity of fuel in the tank. Furthermore, it
must read empty when there's no more useable fuel, not when the tank is empty.

George Patterson
They say nothing's certain except death and taxes. The thing is, death
doesn't get worse every time Congress goes into session.

Let me guess: you are flying one of the new 172's.

Cessna uses a sending unit in these fuel gauges that is notorious for
breaking down. It flickers down to zero every now and then, also causing the
low fuel light on the annunciator panel to flicker. It is harmless, but it
gets worse over time and eventually the gauge will fail.

I know one 172 ME that has had its fuel gauges replaced half a dozen times.

Cessna needs to get on the ball and understand that this kind of quality
control crap went out of style when the Japanese hit the US auto market in
the 1960's. You would think that spending $180,000 on a new airplane
entitles you to a gas gauge that works.

I know if it's at all bumpy and the tanks are anything below full, my gages
are useless. They swing all over the place. Why can't they be damped like
car gages? I suppose they would stay pinned at 0 when the tank was actually
empty.

Barring leaks, I trust my timers. Between 3 and 5 thousand feet at 2200 rpm
I get 2 hours 28 minutes and change out of each tank. I can get another 6 or
7 minutes by slipping with the empty tank on the high side. I also know that
I really have to rock all the bubbles out of the tanks to get the full 18
gallons in each.

mike regish

"Ron Natalie" wrote in message
. ..

"mike regish" wrote in message
news:R%xtb.161414$275.497496@attbi_s53...
Two watches will do that. Or a double timer like I use.

There are a number of reasons why you might be using fuel FASTER than you
are timing it. Let me tell you a few stories.

A few years ago we got the Navion back from annual. The IA had signed
off on it, and
another A&P, Margy, and I put the plane back together. The A&P and I
took it up for a
test flight and after immediately opened her up to inspect for leaks and
all looked good.
The next morning we take off for Oshkosh with Margy in the left seat.
She's negotiating
with Approach for FF and a Class B clearance. I'm looking at the fuel
guage and thinking
"I'm pretty sure I topped the thing off, but we're down gas." I tell
Margy and I tell I'll keep
an eye on it. As it is, we've got over 80 gallons left on board. The
downward trend continues.
Just at this time approach calls back with oru clearance. We're about
midway between
two airports, we tell Dulles that we're going to Leesburg, they offer
assistance.

Get down on the ground, find a mechanic, find that a fuel line is loose
and spraying fuel
all over the inside of the engine compartment. I do a quick calculation
and determine that
we have used 20 gallons in a 20 minute flight. That is 60 GPH!

Another long time rec.aviator put his Cardinal down on a road because he
ran out of fuel
due to a higher than predicted fuel burn. Was found that his carburator
was leaking.

Another rec.aviator ran out of fuel IFR. Nobody yet knows what happened,
but he ran
out way ahead of what preflight planning predicted.

****ty as your average light plane fuel guages are, they are NOT
superfluous.

One thing to consider, you could have a fuel leak in flight. Without
guages, you would never know it.

"Yossarian" wrote in message ...
I understand that functional fuel gauges are required equipment for day VFR
flight. Yesterday during my preflight in a 172 I saw that the right gauge
was functioning intermittently--it would show full, flicker down to zero,
bounce around, etc. Tank was visually confirmed full. Mechanic messed
around with it for a while to no effect.

Would you fly this airplane?

I was once told.. that the Cessna type gauges only have to be accurate when
the tank is empty.. it should tell you so.. it does not need to be accurate
at a full or partially full tank..

it should not say 1/2 when the engine coughs and sputters on an empty tank..

BT

"Yossarian" wrote in message
. ..
I understand that functional fuel gauges are required equipment for day
VFR
flight. Yesterday during my preflight in a 172 I saw that the right gauge
was functioning intermittently--it would show full, flicker down to zero,
bounce around, etc. Tank was visually confirmed full. Mechanic messed
around with it for a while to no effect.

Would you fly this airplane?