Most experienced CFI runs out of gas

I believe that it is a huge mistake to teaach student pilots that at a
given power setting their aircraft will average x gallons per hour.

My 172 averages 8 gallons per hour.
About 18 months ago, on a 2.5 hour flight it averaged 12 gallons per
hour. - Fortunately I had full tanks on takeoff.
6 months ago the same thing happened - fuel consumption went from 8
gallons per hour to 12 gallons per hour.
again I was lucky - I had departed with full tanks.

On both occasions it was the same problem. A seal had failed on one of
my fuel caps and the fuel was siphoning out when airborne.

We KNOW that this can and does happen. So why do we continue to tell
students that if they plan for 8 GPH they will be safe?
It simply isn't true, and it is going to kill someone.

How many students are taught to dip the tanks AFTER they land?
None.
And, as most of them are renting, they go away happily believing that
they burned 8 gph - so they continue to plan that way - even if they are
actually burning a lot more.

So - to all of the instructors out there - why not just teach them to
never trust anything, and if they regularly rent the same aircraft, dip
tanks before and after, so they KNOW the fuel consumption, rather than
continue to operate on some totally arbitrary figure based on a new
aircraft, rather that the 30 year old junker that they actually fly.

OK. Pet peeve over. We now retun you to your regular programming

Tony

--

Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE



In article ,
(Robert M. Gary) wrote:

The local news is reporting that a local CFI (with over 30,000 hours
of instruction giving since the early 1960's) ran out of gas just
short of the airport after picking up a P210 and flying back from
Texas to California. Boy, if it can happen to him, it can happen to
anyone. It will be interesting to see the final facts. Perhaps the
plane was burning way more gas than it should have (the plane had been
bought that day).

-Robert




--

Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE

tony roberts wrote:
I believe that it is a huge mistake to teaach student pilots that at a
given power setting their aircraft will average x gallons per hour.

so what would you teach them? If you dipped before and after and
noticed the fuel consumption all over the place, they still rent and
can only do it by the book plus a safety margin. That safety margin
can't be 50% like your 8 to 12 gph otherwise we'd never get a XC
in as we'd always be stopping for fuel every 5nm. The only
way around this is to have reliable and accurate gauges. I still
don't know why it is that difficult to make these.

Gerald

so what would you teach them?

What would I teach them?

Obviously I'm not communicating well. ( I appreciate your response - it
is just a subject very dear to my heart, after having come close to
being killed because my flight school didn't care enough to teach me how
things really are)

I would teach them to get to know everything there is to know about the
plane that they regularly fly, and to stop relying on data supplied by a
Cessna test pilot flying a new plane on a perfect day with the sole aim
of attaining the best figures he could get for the Cessna marketing
department to use in their promotions. I'd teach them to take ownership
of the situation, and stop relying on information supplied by people
whose butt is not sitting in the plane on the cross country that you
refer to.

And on their long cross country I'd teach them to land and dip the tanks
at the first opportunity, to confirm that the fuel consumption they
used in their calculations is the one that they are actually attaining.
And even then, understand that the seal can still fail at any time.
So if they have 39 gall tanks, and they have been in the air for more
than 2.5 hours, and they fly over an airport with fuel - land, and check
it.

Accurate fuel guages?
We can crawl out of our caves, discover all of the materials and
technology necessary to build a spacecraft, find the fuel, teach someone
to fly it - with total accuracy to a moon landing, AND throw in a
spacewalk on the way, but when they actually land, if they want to know
how much fuel they have left they have to climb up on the wing and dip
the tank with a stick - possibly the same stick we were clutching when
we crawled out of our cave

And round and round we go

Tony

--

Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE




In article ,
Gerald Sylvester wrote:

tony roberts wrote:
I believe that it is a huge mistake to teaach student pilots that at a
given power setting their aircraft will average x gallons per hour.

so what would you teach them? If you dipped before and after and
noticed the fuel consumption all over the place, they still rent and
can only do it by the book plus a safety margin. That safety margin
can't be 50% like your 8 to 12 gph otherwise we'd never get a XC
in as we'd always be stopping for fuel every 5nm. The only
way around this is to have reliable and accurate gauges. I still
don't know why it is that difficult to make these.

Gerald

About fuel consumption: I use a scheme that would reduce the risk. I taxi out
on the tank I will not be using for take-off as a way of verifying that tank is
OK. Run up is done on the takeoff tank, offering some assurance that tank is
good also. (If I was in an airplane with someone who switched to the more full
tank after run up I'd get out!). I fly away half the available fuel in the take
off tank, switch to the other, fly that to near exhaustion, and when I switch
back to the takeoff tank my rule is, land for fuel.. I've modified IFR flight
plans en route to do this. BTW, it's not a big deal in a Mooney. It has 32
gallons usaable in each wing, I get 9 gph leaned at altitude, and the airplane
has more endurance than my bladder.

I remember talking to a guy who just put a CD player in his Vee tail Bonanza,
got caught up listening to some music and forgot to lean. He expected to burn
11 gph, was burning he said 17. That'd be an embarrising way to crash! Nothing
like checklists, huh?

emove (AJW) wrote in message ...
About fuel consumption: I use a scheme that would reduce the risk. I taxi out
on the tank I will not be using for take-off as a way of verifying that tank is

That's one reason I don't like the Cessna "both" selection. In my
Mooney if I ever did run out of gas (because of pilot error or
mechanical problems) I should always have another fresh tank to switch
to. If you run out of gas in a 172, you don't have another tank to
switch to!
-Robert

On 12 Nov 2004 12:27:27 -0800, (Robert M. Gary)
wrote:

If you run out of gas in a 172, you don't have another tank to
switch to!

I think I'd probably explode in a shower of pee if I stayed up long
enough to run the tanks dry in the 172's I rent. ;-)

Corky Scott

"Corky Scott" wrote in message
...
I think I'd probably explode in a shower of pee if I stayed up long
enough to run the tanks dry in the 172's I rent. ;-)

But, at least they're rentals and you wouldn't have to clean up the mess,
right?

In article , Gerald
Sylvester wrote:
in as we'd always be stopping for fuel every 5nm. The only
way around this is to have reliable and accurate gauges. I still
don't know why it is that difficult to make these.

It isn't, and many planes DO have reliable and accurate (enough that
it's easy to tell if you've got less fuel than you thought you should
have) gauges.

--
Dylan Smith, Castletown, Isle of Man
Flying: http://www.dylansmith.net
Frontier Elite Universe: http://www.alioth.net
"Maintain thine airspeed, lest the ground come up and smite thee"

Gerald Sylvester wrote:

tony roberts wrote:
I believe that it is a huge mistake to teaach student pilots that at a
given power setting their aircraft will average x gallons per hour.

so what would you teach them?

I would teach them to fly by the clock -- *but* --
Land if the gauges read less than 1/4 tank.
Land and find out what's wrong if you've been pulling out of one tank for an hour and
the gauge still reads full.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.