Time, running out of fuel and fuel gauges

"George Patterson" wrote

No, I just find it amazing that the slope of the tanks could be severe
enough on
a trike to require a stick like those used on tailwheel aircraft. Hence,
the
question.

The slope of the tank due to dihedral (sp?) is the problem, if the cap is at
a point furthest out from the wing, and the tank is long. (chordwise)

The same principle, only in reverse, would hold for a gauge sending unit in
the lower end of the tank. It would read completely full, until the top
burns off of the tank, but it would tell how low your gas level is, in
spades.

That is the beauty of Jim's capacitance sending unit, because you can
install it lengthwise, from the bottom inboard to the top outboard at the
cap. It will start going down when the first fuel is used, and still be
going down, right up until the fan stops turning.
--
Jim in NC

"Ed H" wrote in message
. ..
Question for all: how accurate are fuel flow meters?

I have a very simple one, shows only current fuel flow, and total fuel used
since the last reset. I don't even recall what brand it is.

My experience with it is much more like Peter R.'s than John Smith's. It's
extremely accurate, and consistently predicts how much fuel will be required
to top off the tanks to less than a gallon (to within 0.5 gallon is
typical).

Pete

Pete et al
With all due respect for the modern electronics and advancements, I
guess I am just one of the soon to be gone dinosaurs and have seen all
too many occasions when the modern technology takes a vacation when you
need it most. Reliance on anything electrical with little regard for
anything else in the way of aviation aids is, to my mind, just another
example of an unexplained NTSB report in the making.
I flew for many years in remote areas without anything but common sense
and the teachings of an old CFI who was very demanding and required
that I knew our exact location at any given time, and give him the
number of gallons we'd take on at refueling. I smile to think of how
easy it would have been if we'd had GPS for an aid. We didn't even have
ADF in many regions and in many cases no accurate charts.
Lovely to have the modern technology working, but it will never replace
the human brain. The human brain is useless unless it has the proper
knowledge to work with.
My point is to not rely solely on electrical components/indications.
Fly safe
Ol S&B

My JPI is always within a gallon when I top up.

My mistake. Thanks for pointing it out.
--
Gene Seibel
Hangar 131 - http://pad39a.com/gene/plane.html
Because I fly, I envy no one.

Dylan Smith wrote:
snip
So my lesson is - keep track of time AND cross check time and your
expected fuel burn with the fuel gauges. If the gauges show less than
expected, land and check it out. They might well be right.


That's the key to using the often less-than-accurate fuel gauges
found on most aircraft. Even though they may not tell you the exact
quantity of fuel in each tank, an unusual reading can tip you off to a
fuel leak or higher than expected fuel burn.

One more trick that I keep in the bag is to burn fuel from one tank
at a time (even when flying a high wing that allows both). If you
have a leak or unusually high fuel burn, you'll be alerted when a tank
goes dry ahead of schedule. At that point, you (hopefully) have fuel
remaining in the other tank to get you safely on the ground. When
flying on a "both" setting, by the time you realize that something is
wrong, you may have emptied both tanks.

John Galban=====N4BQ (PA28-180)

S&B wrote:

My point is to not rely solely on electrical components/indications

I agree. This is why I always take along a cross country flight log
with blocks at each waypoint for estimated time of arrival and actual
time of arrival. En route, I use this log and a clock to monitor fuel
usage.

OK, so the XC log is produced by Jepp's FlightStar flight planning
software, but I could produce one by hand if I had to.

--
Peter

wrote in message
oups.com...
[...]
My point is to not rely solely on electrical components/indications.

Who said anything about making the fuel flow meter one's sole source of
information with respect to fuel quantity?

Geez...take a chill pill. The correct "takeaway" here is that a) fuel flow
meters ARE useful (when properly calibrated) and b) you cannot trust any one
source of information (not even your watch) and so the more sources of
information you have available, the better (so you can cross-reference).

It's got nothing to do with being "one of the soon to be gone dinosaurs".
Other than a dinosaur who refuses to take advantage of new technology *in
addition to* their existing tools may be gone sooner rather than later, that
is.

Pete

Pete
You misread or misunderstand me. I said not to rely SOLELY on
electrical. I'm delighted to see the modern advances and electronics
and use them as often as they are available. But, I've been around a
long time and have yet to see a foolproof system. I've encountered more
than a few in-flight failures of nearly everything that can go wrong!
Fortunately I was close enough to make a landing when I had some
serious failures in flight.
BTW, what is a "takeaway"? Is that a new word that us old english major
dinosaurs have to learn? Of course I understand the meaning or intent,
I think, but have never seen it used before.
geeezzzo....chill pill?
fly safe and don't take anything for granted
Ol S&B

Before you get too excited about FAR part 23, remember most of the planes we fly were certified under CAR 3, and don't have to conform to part 23 regarding fuel gauges. Only newer aircraft certified under part 23 have to conform to this regulation.

That's not to say that it isn't a very good idea to get your gauges calibrated and make them as accurate as possible. And if your fuel gauge says empty, then land ASAP and figure out the problem.

John


[quote=Bob Moore;269828]"Gene Seibel" wrote

The only regulations for fuel gauges are that they read correctly at
empty. They are not reliable for determining the amount of fuel in the
tanks, but as they approach empty, they should be believed.

Bull****! I am repeating an e-mail that I sent to a young man
who posted the same information on his web site.

Russ......

I stumbled on your web site while searching for some C-172 Fuel Cap
information.
I found the following statement which while completely false, seems to be
circulating quite widely.

"The FAA only requires the gauges to read accurately when the tanks are
empty. Yeah, you're right, that's really stupid, but it's the law."

I have quoted the applicable portion of the Federal Aviation Regulation
"law".

Section 23.1337: Powerplant instruments installation.
(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.......