Hi Michael

That was a great post - and a keeper.
Thanks for posting it - there are lots of lessons in there for anyone
that read it.

He took one look at
me and at the fuel gauge, and said "Don't ever run her that low, Mike.
She'll quit on you." No kidding.

LOL - I have seen a few like that!

Tony
C-GICE

In article .com,
"Michael" wrote:

30 minutes is not a suggested SOP - it's a minimum!
It's designed to help you put it down somewhere - anywhere!
I appreciate the honesty in your post - but I cannot support the concept
that it is OK to regularly plan landings with a 30 minute minimum

I wonder what you would think of an operation I used to fly for...

91.151 Fuel requirements for flight in VFR conditions.
(a) No person may begin a flight in an airplane under VFR conditions
unless
(considering wind and forecast weather conditions) there is enough fuel
to fly
to the first point of intended landing and, assuming normal cruising
speed --
(1) During the day, to fly after that for at least 30 minutes;

Notice it says begin - once the flight is started, there are no rules.

When I had something less than 400 hours, I started towing gliders. It
was a weird deal - the towing operation was commercial, but contracted
almost exclusively to a club. Two guys owned and ran it, and used
qualified club members for tow pilots. At one time this was done under
an SSA exemption, but afterwards the FAA made the exemption unnecessary
by adding glider towing to the list of exceptions to private pilots
flying for compensation or hire (61.113(g)). The operation used two
worn out converted cropdusters - one powered by a Lycoming O-360, the
other by a Lycoming O-470. The strip was not terribly short (3000 ft
or so) but it was very rough and obstructed, and we often towed in 100
degree weather. To maximize takeoff and climb performance, we would
put no more than 15 (or was it 20?) gallons in the tank (singular), and
we would fuel up once we were down to 5.

We climbed at full throttle and full rich mixture (tows were rarely
above 3300 MSL, and the engines always ran hot) at about 70-80 kts, and
with a climb prop that meant an O-360 would average about 15-17 gph.
The O-470 had a seaplane prop (meaning as fine a pitch as the
certification rules allowed) and would make nearly full power in the
climb, averaging maybe 22-24 gph.

It was argued that this was technically legal, since the first point of
intended landing was the point of takeoff (requiring zero fuel to
reach) and thus the flight always began with with more than the 30
minute required VFR reserves, even assuming full power cruise. Once
the flight began, well, there aren't really any rules, and who is to
say the flight ended until we shut down? I will be the first to admit
that this is a grey area, and I would sure hate to make this argument
in front of an FAA inspector if I ran out of gas. I will also be the
first to admit that this sort of operation cuts the margins to the
bone, and that running out of gas in this sort of operation is a matter
of when, not if. By the time I did it, I was not the first. Or the
second. Or the fifth...

On the bigger-engined plane, 5 gallons still allowed for a reserve of
over 10 minutes at climb power. Jet fighters routinely land with less
reserve than that, though I doubt they ever take off that way.
Considering that the field was huge (it could not be shut down by one
accident, or even two), considering that we only flew day-VFR, and
considering that the plane could very effectively cruise or loiter at
45% power or less, where the 5 gallons would actually allow for over 30
minutes of loitering or slow cruise, one could argue that it wasn't
really that bad. As long as the pilots paid attention and the fuel
gauges worked, nothing should have gone wrong.

The real problem was that our fuel burn was nothing like constant. You
never knew how much fuel a tow would take. Sometimes you made release
altitude in under 2 minutes, sometimes it took closer to 10. The
descent depended an awful lot on how hard you were willing to bank
(descents were made with a little bit of power to keep the engine warm
and in a steep banked turn - 60 degrees and up) and how low you were
willing to spiral (some would spiral into the base-to-final turn as low
as 200 ft, although our operating procedure - yes, we had one, in
writing - called for 500-1000). Then there was taxi (and again, that
time depended on whether or not you landed downwind to cut the
turnaround, as the book called for when the winds were below 10 kts) to
the hookup point and waiting for hookup at idle. With all there was to
do, timimng wasn't a realistic option - you often flew tired and
dehydrated, and you would inevitably forget to time something. We
depended on those fuel gauges.

The fuel gauges on the planes were excellent. They were mechanical
ball-and-float arrangements linked to an indicating needle. They were
VERY repeatable. We never had one break, which is how one might assume
things would go wrong. That's a funny thing I've learned about flying
- if you have an operation where the safety margins are slim, and where
the failure of some component can cause a real problem - you will
usually see that problem, but it won't be due to the failure of the
component but because the pilots are just cutting the margins too close
or screwing up.

My own screwup came from assuming that just because the small-engine
plane's tank really held 5 gallons when the needle said 5, the same
would be true of the big one. It really held 3 gallons - worth about 8
minutes in the climb. It was just a hair over that (or maybe right
there) when I taxied up and saw there was only one sailplane waiting to
launch. It's a rare tow that takes 8 minutes, but when I saw the heavy
glass ship, I knew it was trouble. Two pilots fly it - father and son.
The son is a good stick, flies coordinated, and would be no problem.
The father doesn't fly it coordinated, and heavy as it is, the climb is
often 300 fpm or less and takeoff is always marginal. I saw the father
getting in. Damn.

I figured I had more than 10 minutes of fuel - more than enough to get
the job done. Also at the back of my mind was the thought that I
didn't really want to be carrying any more than I had to - it was hot,
and there was almost no wind. We hooked up and went.

There wasn't much lift, and he wanted to go to 4000. Damn. We got
there, but by that time the needle wasn't even moving. I knew I was on
fumes. I spiraled down to 1500 ft or so, entered the pattern at idle
power, hit my key point a bit high, rolled into a slipping turn to base
to scrub off the altitude - and as soon as I went out of coordination,
the engine coughed and quit. I wasn't even surprised.

I kept only a mild slip going on base and in the turn to final, and
came up high on final. No worries - I had lots of field (about 3 times
what I needed for comfort) and the plane had a powerful rudder and big
fuselage. It slipped just fine, if you ignored the pitch oscillations
that made the ones that caused Cessna to placard the C-172 seem like a
joke. I racked it over, slipped off the extra altitude, lined up, and
started my flare about 500 ft past the threshold. As I regained
coordinated flight and raised the nose, the last dregs of fuel got to
the aft-mounted intake and the engine caught. Of course it was at
idle, so no harm done. I had just enough to taxi over to the pumps and
shut down.

One of the owners was standing by the fuel pump. He took one look at
me and at the fuel gauge, and said "Don't ever run her that low, Mike.
She'll quit on you." No kidding.

There was no chewing out. He knew the lesson had been learned.
Cheaply.

There were two partners in the tow plane operation, and he was the one
who supplied the wisdom. He knew what had to be done, and whom to
trust. Some pilots he put on the towing schedule as soon as they could
meet the insurance requirements (and maybe a might sooner), others
checked out but stayed on crew for years, dragging gliders around on
the ground, flying a little bit here and there to fill in when there
were a lot of planes waiting. He also made sure the planes were kept
up - maybe not good enough that some fed who never had to have a real
job wouldn't ground them, but good enough that the experienced pilots
felt good about flying them. He loved those towplanes. His happiest
moments were spent in them. I don't know that he ever really cared
about the gliders, though he flew them at times.

He lost his battle with cancer that year. A friend of mine and I went
to see him a few days before he died. The doctors had given him six
months when he was first diagnosed. He had fought on for half a
decade, flying most of that time, but the fight was done and he knew
it. We showed him videos of our new gliders being towed to altitude,
and he came alive. It was hard to believe it was the end, but it was.

The club cancelled flying the next weekend so everyone could go to the
funeral. My friend and I didn't go. Instead, we went to the
gliderport. There were a few others of like mind there. And so I
strapped into one of the planes that he loved so much, and they pulled
out their gliders, and I said my goodbyes from the towplane. Somehow
it seemed more fitting.

Things went downhill after that. The maintenance began to be deferred
or just not done right. The remaining partner had pretty good hands,
both as a mechanic and as a pilot, but he lacked the wisdom of his
partner. The new partner in the business was a novice. The planes got
scarier, the flying got scarier. At least half a dozen pilots had run
out of fuel before me, but always in the same way I had - at altitude
or on the way down, aware they were at the edge, and with no damage or
even any significant inconvenience - every one easily deadsticked into
the field, not only with no damage but with the successful outcome
never seriously in doubt.

Now the more experienced pilots were drifting away, because the planes
were scaring them. The pilots that had been kept off the regular
rotation now got their chance. One pilot ran out of gas on the
climbout, at 800 ft. Fortunately he made it back to the field. One of
the engines wasn't making power, but the owner wouldn't listen. Static
RPM meant nothing to him. Eventually it was opened up - and by then
the cam lobe that had come off (sic!) had rattled around enough that
the engine wasn't even repairable. It was replaced, but then the prop
was lost in flight. The operation was down to one plane. I was long
gone by then.

The last straw was a fuel exhaustion accident. The tow pilot had been
there long before me, but somehow couldn't get on the regular rotation.
There was no real mystery to it - it was known that he really didn't
have enough on the ball to consistently perform in a marginal operation
like this. But the partner that knew this died, and the roster of tow
pilots shrank, and he got his chance.

Like the many before him, he ran out of gas. He was coming in dead
stick, and he decided he was too high. He was high (maybe 200-300 ft
over the threshold) and probably fast too. He could have slipped, made
S-turns - but instead he tried to make a 360. He must have realized he
wasn't quite as high as he though partway through the turn, because he
slowed down. It wasn't enough. The plane was crashed half a mile from
the approach end of the runway, and is a total loss. He walked away.

The FAA came out to investigate. The feds were there about an hour.
The pilot may yet get cited for something. The operation continues
unchanged.

Michael




--

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