Flying w/faulty gas gauge

"Ron Natalie" wrote in message
m...

"Angus Davis" wrote in message
...

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

Sorry, the FARs don't say that. The FARs don't say anything about
accuracy.
The much misattributed FAR about them being empty just says that the E
mark
means zero usable.

If they show full when
the tanks are 1/4 full, that is not a problem in so far as the FARs are
concerned.

91.205 says you must have operational guages. In this case the guage is
NOT operating
the way it was designed. If the thing is really bouncing between 0 and
Full on the ground
there is something seriously wrong. Not only is it hardly legal, I'd
really question what
was going on.



Well, I'd certainly want to know why a gauge was flicking
around, but being pedantic (as I would be if called on it
by the FAA), how am I to know if my gauges are operational?

For that, I'd go to my POH for guidance. My POH tells me
that my fuel gauges should read 'red line' when there is no
fuel in the tank. It says nothing else. So I'd argue that I could
reasonably conclude my gauges were just fine if they showed
full when in actual fact they were only 1/4 full. And since
the FAR's insist I operate my plane consistently with the
POH & flight supplements, I'd claim regulatory backing for
this position.


--
Dr. Tony Cox
Citrus Controls Inc.
e-mail:
http://CitrusControls.com/

"Tony Cox" wrote in message
nk.net...
Well, I'd certainly want to know why a gauge was flicking
around, but being pedantic (as I would be if called on it
by the FAA), how am I to know if my gauges are operational?

Per the FAR, if they show the amount of fuel in the tank, they are
operational. If they don't, they aren't. It's not rocket science. If you
have gauges that show full tanks even when they are only 1/4 full, the
gauges are not in compliance with the relevant regulation.

For that, I'd go to my POH for guidance. My POH tells me
that my fuel gauges should read 'red line' when there is no
fuel in the tank. It says nothing else.

Just because the POH only describes your "red line" for the zero fuel point,
that doesn't mean there aren't additional requirements for accuracy.

Pete

91.205 For VFR flight during the day, the following instruments and
equipment are required:

(9) Fuel gauge indicating the quantity of fuel in each tank.

http://www.access.gpo.gov/nara/cfr/c...4cfr91_00.html



"Angus Davis" wrote in message
...
Yossarian wrote:

I understand that functional fuel gauges are required equipment for day
VFR
flight.

Per the FARs, your gauges were functional. The only requirement is that
when the tanks are empty, the gauges read empty. If they show full when
the tanks are 1/4 full, that is not a problem in so far as the FARs are
concerned. Repeating, the only regulatory requirement is for gauges to
be accurate when the tanks are empty. That's why you should pay little
attention to them at all, and do your fuel calculations with diligence.
-angus

I have heard this repeated for quite a while, and I can't find the pertinent
section of the aircraft certification regs. Would you mind posting the chapter
and verse where I can find this requirement?

Jim


The only requirement is that
-when the tanks are empty, the gauges read empty. If they show full when
-the tanks are 1/4 full, that is not a problem in so far as the FARs are
-concerned.

Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

"Jim Weir" wrote in message news
I have heard this repeated for quite a while, and I can't find the pertinent
section of the aircraft certification regs. Would you mind posting the chapter
and verse where I can find this requirement?

Jim


It doesn't say that. 23.1337 says the guage must be calibrated (but doesn't give any specific
accuracy). The part that people keep passing around by is the (1), but they ignore the fact
that it comes after "In Addition" . The empty pronouncement just says that the bottom mark
is supposed to be zero usable as opposed to bone dry:

(b) Fuel quantity indication. There must be a means to indicate to the flightcrew members the quantity of
usable fuel in each tank during flight. An indicator calibrated in appropriate units and clearly marked to
indicate those units must be used. In addition:
(1) Each fuel quantity indicator must be calibrated to read "zero" during level flight when the quantity of
fuel remaining in the tank is equal to the unusable fuel supply determined under § 23.959(a);

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.

It's only requirement is that it reads empty when the tank is empty. Got a
watch? That's a hell of a lot better gas gage than that thing on the panel.

mike regish

"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?

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.

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.

"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...