Flying w/faulty gas gauge

one watch and pencil and paper..


"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.

mike regish

"ArtP" wrote in message
...
On Sat, 15 Nov 2003 13:40:58 -0600, "Roger Tracy"
wrote:

Yes. I go by tach time anyway and can peg fuel consumption
pretty close.

Spoken like a high winger. For us low wing types we have to know how
much fuel is in each tank. Since climb, cruise, and descent all use
different amounts of fuel it is hard to know how much is left in each
tank. Sooner or later we come to the point when the POH says switch to
the fullest tank. We need the gauges to know which one that is.

Ron Natalie wrote:
I believe certification only requires that the gauge show empty when
the tank is empty.

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

Empty... unusable... Not much difference in my book. If there is no fuel
flowing to the engine, it's empty!
Of course, if you know the Chinese fuel management technique, you can
extract some or all of the unusable fuel.

that isn't the part that isn't true

I didn't expect this thread to spark this much discussion!

"john smith" wrote in message
...
Ron Natalie wrote:
I believe certification only requires that the gauge show empty when
the tank is empty.

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

Empty... unusable... Not much difference in my book. If there is no fuel
flowing to the engine, it's empty!
Of course, if you know the Chinese fuel management technique, you can
extract some or all of the unusable fuel.

Jim Weir wrote:

The function of a fuel gauge in a Cessna is to tell whether or not the master
switch is on.

Yeah, the gauges in my Skyhawk have never worked worth a damn. Every
couple of years my mechanic does some scraping on the electrical
contacts of those crappy little float things accessed behind the
filler caps and they work well enough to pass inspection. I forget
how many hundred dollars it was going to be to replace them. Doubt
replacements would do any better considering how poorly the gauges
seem to work in most Cessnas.

Jim Rosinski
N3825Q

"BTIZ" wrote in message
news:niBtb.3221$Ue4.826@fed1read01...
| 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..

You were told incorrectly, but you are in pretty good company. Even Rod
Machado made this error in one of his columns. He wrote back to me and told
me that he thought my interpretation of the regulations was probably more
correct. (But then, John King teaches the equal transit theory of lift, so
even "world famous" flight instructors like us get things wrong sometimes.
:-) Seriously, if you took all the faults and bits of misinformation taught
by just the top ten flight instructors in the country and put them into one
guy, you would probably have a really terrible flight instructor. But I
digress.)

The actual regulation states that the gauges must be calibrated so as to
read empty when usable fuel (as opposed to total fuel) is gone. Part 91
requires fuel gauges to indicate the quantity of fuel in each tank. I do not
believe that the momentary flickering caused by a bad sending unit in the
Cessna tanks seriously interferes with getting an accurate reading of the
amount of fuel in the tank. It is an annoyance at worst and you have to
watch it very closely to even see it.

Just how accurate a fuel gauge has to be to meet the requirements of Part 91
is not spelled out. I know of one guy (one of my instructors, actually -- I
was there) who was busted because his gauge read 2/3 full when it was
actually full. I know of at least one airplane that the gauge always reads
zero until you start the engine. I wonder how an inspector would feel about
that?

Would you fly this airplane?

Do you have enough gas to fly the airplane ? Yes. Is it legal ? No.
Does anyone know ? Yes. That's your biggest go/no-go problem at this
point.

Seriously, if this is your airplane, try wiggling the trim pot on the
back of the gauge and give it a shot of corrosion-X. Corrosion buildup
on the pot contact is common, resulting in jerky movement, indication
that comes back with tapping on glass, etc. That's not legal either,
BTW, so don't tell anyone you did it !

Would you fly this airplane?

No.

Remember that you should be flying the airplane for pleasure. If your fuel
gauge shows empty it is not fun to fly. Like the others have said it is
possible a fuel leak changed your calculations.

I wonder how many pilots on this newsgroup have run their airplane to where
they used ALL the useable fuel. Try it, it is NOT fun. I had it happen in
Mexico where fuel is not always available. I would rock the wings to check
movement in the fuel gauges. The last check I did minutes before landing
showed NO movement, dead. Luckily I landed, of course making a high approach
in case the engine quit. When I fueled the total gallons added was exactly
the useable amount of fuel. Never do that again....and never went back to
Mexico.

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

That probably explains why the airport owner was mulling the
possibility of replacing the cork float in Zero Six Hotel.

The only gas gauge I trust is my watch. Two hours and it's time to
look for a nice smooth field.

all the best -- Dan Ford
email: (put CUB in subject line)

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

I'm in the process of replacing the Stewart-Warner steam gauges in the 182 with
the Mitchell modular line. We're doing both fuel gauges and both oil gauges.
I'll do an analysis of my installation for a Kitplanes column, probably about
this time next year for the whole process to take place.

Jim



(jim rosinski)
shared these priceless pearls of wisdom:

-Jim Weir wrote:
-
- The function of a fuel gauge in a Cessna is to tell whether or not the
master
- switch is on.
-
-Yeah, the gauges in my Skyhawk have never worked worth a damn.

Doubt
-replacements would do any better considering how poorly the gauges
-seem to work in most Cessnas.
-
-Jim Rosinski
-N3825Q

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