Post-Annual Flight

On Feb 21, 4:15*pm, wrote:
* *(9) Fuel gauge indicating the quantity of fuel in each tank.

If "you can't trust it to within a quarter tank", you should probably
get it fixed.

Yeah, I know, it is common and nobody seems to care, but that isn't
what the regs say.

The regs are kind of vague about how precise and accurate the
indication has to be, so there's some leeway. But a gauge that's flat-
out broken is obviously beyond the pale.

On Thu, 21 Feb 2008 20:51:30 GMT, Jay Maynard wrote:

I won't argue with that statement. I was simply taught that aircraft fuel
gauges are chronically unreliable to the point that they should be ignored,
and that they should never be considered "working".

"The FAA has said repeatedly that the intent of FAR 23.1337(b) and FAR
91.205(b)9 is to prevent fuel-exhaustion accidents. If you have a fuel
gauge that doesn¢t give you a useful indication of the amount of fuel, it
is not doing its job.

In particular, if the gauge is so inaccurate that you prefer not to look at
it, that¢s a violation of the letter and spirit of the regulations."

http://www.av8n.com/fly/fuel-gauges.htm


--
Dallas

wrote:

If "you can't trust it to within a quarter tank", you should probably
get it fixed.

Yeah, I know, it is common and nobody seems to care, but that isn't
what the regs say.



BTW, if your gauges don't show repeatable indications, it is time to
overhaul the gauges, the senders or both. While the gauges may not be
calibrated to show the actual quantity remaining, the FARs do require
them to indicate accurately at zero (and they generally do if they are
working at all). Regardless, you shouldn't be getting a 1/4 tank
variation from day to day with the same amount of fuel in there. While
the markings on mine don't correspond too well to the actual fuel
quantity, the position of the needle for a given amount of fuel is
fairly constant unless the electrical system is off and the battery
running down (don't ask me how I know that).

Tha FARs basically require the gauge be operating (which means it
increases when you add fuel and decreases when you burn fuel), and that
it is accurate when the tank is empty. There is nothing there about
calibration otherwise, and I'd bet that most of the airplanes out there
have gauges that meet the rules (the exception being those that don't
indicate at all).

On Feb 21, 4:21*pm, Ray Andraka wrote:
It should tell you if the tank is empty. *The fuel gauge is required to
read correctly for an empty tank.

There's an urban legend that the fuel gauge is only required to be
correct for an empty tank. The legend apparently arises from a bizarre
misreading of 23.1337b1. What 23.1337b1 actually says is just
clarifying that the 'empty' reading must correspond to zero USABLE
fuel, as opposed to zero TOTAL fuel. There is nothing whatsoever to
suggest that non-empty readings needn't be correct--that would be
absurd. (If it were true, a gauge that ALWAYS says 'empty' would be
legal! You could just write 'empty' on a piece of paper and call that
your fuel gauge!)

The requirement for indications of a tank's fuel level (not just on
empty) is stated in 91.205b9, 23.1305a1, and 23.1337b.

On 2008-02-21, Dallas wrote:
In particular, if the gauge is so inaccurate that you prefer not to look at
it, that's a violation of the letter and spirit of the regulations."

If that's the case in real world aviation, then every aircraft I flew while
I was flying regularly, way back when, would have been grounded waiting a
fix that never came.

Why is it so remarkable that the fuel gauges in the new aircraft I'm looking
at are actually considered reliable? I've hear dlots of comments to that
effect. "Hey, fuel gauges you can believe! Wow!"
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
http://www.hercules-390.org (Yes, that's me!)
Buy Hercules stuff at http://www.cafepress.com/hercules-390

I thought placarding as "INOP" was only legal for non-required
equipment? Required equipment being what is listed in 91.205 ANDed
with the aircraft equipment list?

Apparently having three other fuel tanks to choose from makes a single
tank's fuel gauge "non-required"...
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

http://www.metcoaire.com/products/pr...straight.shtml

Scroll down to 'Replacement Fiberglass Tail Cone' section.
Metco's fiberglass parts are first rate quality.

Thanks for the link!

The repaint can't be all that bad. We had a custom paint job on old
wheelpants accurately duplicated onto a set of new ones by a local
auto paint & body shop for only a couple hundred dollars materials &
labor.

All the stripes on the plane (3 different colors) are on that tail cone,
plus the base coats of gray and white. What a PIA to do, but I'm afraid it
will have to be done.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Yikes. You didn't even take the precaution of always using the other
tank when landing, rather than using the one that doesn't tell you if
it's about to run dry?

Placarding INOP is for optional devices. Working fuel gauges are
required for airworthiness.

IMO having four gas tanks makes a single one of them "optional". After the
gauge went TU, we notified our A&P, who agreed that we could wait until the
annual inspection to fix it. We placarded it as INOP, and didn't use it on
take-off or landings.

How do visual inspection or your timer tell you if you've got an in-
flight fuel leak? That's an important reason for the fuel-gauge
requirement.

That's why we didn't use that tank for take-offs or landings. In cruise
flight, if the thing ran dry, we could always change tanks. It never did,
of course.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

On Feb 21, 5:39*pm, "Jay Honeck" wrote:
Placarding INOP is for optional devices. Working fuel gauges are
required for airworthiness.

IMO having four gas tanks makes a single one of them "optional". *

The tanks themselves may be optional, but a working gauge for each
tank is required equipment (see below).

After the gauge went TU, we notified our A&P, who agreed that we
could wait until the annual inspection to fix it. *

Does an A&P have the authority to waive the basic airworthiness regs
for you? (That's not a rhetorical question--I would guess not, but
having never owned a plane, I don't really know.)

We ... didn't use [that tank] on take-off or landings.

Ok, I'm relieved to hear that. Previously, you made it sound as though
you just placarded the plane as unairworthy, and then flew it without
further precautions.

In cruise flight, if the thing ran dry, we could always change tanks. *

Fuel starvation isn't the only reason to want to know if there's a
leak. A fuel leak also implies an in-flight fire risk, and an inop
fuel gauge deprives you of an important warning sign.

On Feb 21, 5:27*pm, "Jay Honeck" wrote:
Apparently having three other fuel tanks to choose from makes a single
tank's fuel gauge "non-required"...

Huh? FAR 91.205b9 requires, "in operable condition", a "fuel gauge
indicating the quantity of fuel in each tank". Which part of "each
tank" makes a single tank's fuel gauge sound optional?