Post-Annual Flight

Jay Honeck wrote:
I never use the fuel gauges for anything
other than passing reference, since we do everything by visual
inspection and the timer

Doesn't everyone?

Do people actually use the fuel gauges?

On Feb 21, 2:23*pm, B A R R Y wrote:
Jay Honeck wrote:
I never use the fuel gauges for anything
other than passing reference, since we do everything by visual
inspection and the timer

Doesn't everyone?

Do people actually use the fuel gauges?

Are you serious? You're supposed to frequently cross-check your timing
calculations against the gauges, in part so you can discover a fuel
leak before it's too late. That's why an inoperative fuel gauge makes
a plane unairworthy, and illegal to fly.

On Feb 21, 12:15*pm, "Jay Honeck" wrote:
How were you able to fly in the meantime? A plane is not airworthy
without a working fuel gauge for each tank (91.205b9). Can one get a
waiver for this sort of thing?

In an incredible display of aviation daring...I placarded the gauge as INOP,
and flew the plane. *

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.

I never use the fuel gauges for anything other than
passing reference, since we do everything by visual inspection and the timer
in our Garmin GTX-327 transponder.

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.

If I wasn't looking for something not working in the panel (a habit I've
formed after a decade of "maintenance-induced failures") I'm not sure how
long it would have taken for me to accidentally notice it wasn't working.

Yikes.

On 2008-02-21, wrote:
I never use the fuel gauges for anything other than
passing reference, since we do everything by visual inspection and the timer
in our Garmin GTX-327 transponder.
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.

How does a fuel gauge that's so unreliable that you can't trust it to within
a quarter tank tell you whether you've got a fuel leak? That description
applies to every aircraft I flew during my primary training, late 1970s
vintage Cessna and Piper and Grumman products (this was in the late 1980s).
I was taught to verify the tank's level on preflight, and use time and
consumption per hour to figure usage.
--
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

On Feb 21, 3:34*pm, Jay Maynard
wrote:
On 2008-02-21, wrote:

I never use the fuel gauges for anything other than
passing reference, since we do everything by visual inspection and the timer
in our Garmin GTX-327 transponder.

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.

How does a fuel gauge that's so unreliable that you can't trust it to within
a quarter tank tell you whether you've got a fuel leak?

Say you're expecting the tank to be two-thirds full, but the gauge
says it's one-eight full, and dropping fast. Then you should suspect a
possible leak, and land the plane quickly.

You're right that more-accurate gauges would be even more useful. But
that's no reason to ignore (or to illegally forgo) what limited
usefulness there may be.

I was taught to verify the tank's level on preflight, and use time and
consumption per hour to figure usage.

I was taught to do that AND to cross-check with the gauges, and to
trust whichever method gives the lower indication at the moment. I was
taught to check the gauges again when switching tanks, to make sure
I'm switching to the fuller one as expected. I was taught to check the
gauges when preparing to land, to make sure I'm using the fuller tank
and that it's not about to run out.

I was also taught not to fly a plane that's not legally airworthy.

But what matters isn't what you or I happened to be taught, but rather
what makes sense. Having and using working fuel gauges makes a great
deal of sense, for the reasons just given.

On 2008-02-21, wrote:
But what matters isn't what you or I happened to be taught, but rather
what makes sense. Having and using working fuel gauges makes a great
deal of sense, for the reasons just given.

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".
--
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

On Feb 21, 3:51*pm, Jay Maynard
wrote:
On 2008-02-21, wrote:

But what matters isn't what you or I happened to be taught, but rather
what makes sense. Having and using working fuel gauges makes a great
deal of sense, for the reasons just given.

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".

I think that's half-right, and the half that's right is very
important: you should never trust fuel gauges when they say you've got
MORE fuel than you calculate. But if the gauges say you've got very
much LESS than you expect, you should be concerned. And you need to be
checking the gauges frequently, so you can notice if that occurs. (And
of course, you can only do that if the gauges are operable, as they're
required to be.)

wrote:


How were you able to fly in the meantime? A plane is not airworthy
without a working fuel gauge for each tank (91.205b9). Can one get a
waiver for this sort of thing?


The gauge was working just fine. The sender that drives the gauge,
however, wasn't sending it good data because of the missing float. :-)

In rec.aviation.owning Jay Maynard wrote:
On 2008-02-21, wrote:
I never use the fuel gauges for anything other than
passing reference, since we do everything by visual inspection and the timer
in our Garmin GTX-327 transponder.
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.

How does a fuel gauge that's so unreliable that you can't trust it to within
a quarter tank tell you whether you've got a fuel leak? That description
applies to every aircraft I flew during my primary training, late 1970s
vintage Cessna and Piper and Grumman products (this was in the late 1980s).
I was taught to verify the tank's level on preflight, and use time and
consumption per hour to figure usage.


23.1337(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...

23.1337(b)(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...

91.205 Powered civil aircraft with standard category
U.S. airworthiness certificates: Instrument and equipment
requirements.

(a) General. Except as provided in paragraphs (c)(3) and (e) of this
section, no person may operate a powered civil aircraft with a
standard category U.S. airworthiness certificate in any operation
described in paragraphs (b) through (f) of this section unless that
aircraft contains the instruments and equipment specified in those
paragraphs (or FAA-approved equivalents) for that type of operation,
and those instruments and items of equipment are in operable
condition.

(b) Visual-flight rules (day). For VFR flight during the day, the
following instruments and equipment are required:
...
(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.


--
Jim Pennino

Remove .spam.sux to reply.

Jay Maynard wrote:

On 2008-02-21, wrote:

I never use the fuel gauges for anything other than
passing reference, since we do everything by visual inspection and the timer
in our Garmin GTX-327 transponder.

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.


How does a fuel gauge that's so unreliable that you can't trust it to within
a quarter tank tell you whether you've got a fuel leak? That description
applies to every aircraft I flew during my primary training, late 1970s
vintage Cessna and Piper and Grumman products (this was in the late 1980s).
I was taught to verify the tank's level on preflight, and use time and
consumption per hour to figure usage.


It should tell you if the tank is empty. The fuel gauge is required to
read correctly for an empty tank. I use a timer and visual inspection
as my primary, but I also use the fuel gauges to verify that my fuel
burn is approximately what I expected it to be.

Jay's flight manual tells him to position the fuel selector on the
fullest tank (he's got four of them) in his pre-landing check list. If
I were in his shoes, I would plan my flight so that the tank with the
inop gauge was used early in the flight so that one of the others is the
fullest tank on landing. For take-off the same advice is in the AFM.
In that case, you have presumably just visually checked the fuel level,
so you can safely take off on the tank with the inop gauge. Still, as
the inboards are the "main" tanks and are supposed to be filled last and
used first (at least on a Six, which has the same fuel system), I'd be
getting that gauge fixed sooner than later.

I did have one of my tip tank gauges stop working about a decade ago for
the same reason (float fell off), and like Jay I put that off until the
annual, but I also didn't use the tip tank during that time the gauge
was broken and placarded it as tank unusable.