Roadkill

[Colonel Sanders]

Was refuelling one of my airplanes recently, when
I just had to stop and watch the show.

A couple of guys were running up a little twin - the
kind of aircraft that makes everyone drop their
pants in excitement ... "MULTI-TIME!!!", they shriek.
I don't get it.

Anyways, as best as I could tell, these guys were
using a checklist a thousand pages long to run the
little twin up. "Logging Garmin 430 time", the guy
next to me observed. Perhaps they were trying for
the Guinness Book Of World Records for The Longest
Runup By A Light Piston Twin.

A lot of time went by, and finally they feathered the
right engine, and it came to a stop with the blades
totally coarse pitch. After many, many tries they
were able to restart it, and the lengthy runup continued
for a considerable length of time.

Inevitably, they taxiied out for departure, and I couldn't
help but wonder what would happen if anything went
wrong. They couldn't even successfully perform a runup.

Their brains were certainly at 100% for a normal start,
taxi, runup and takeoff. They had no excess capacity if
anything went wrong. Not even with a really, really
thick checklist, which actually isn't a substitute for brains,
skill and systems knowledge, regardless of what people
tell you.

You have to wonder how many people fly like that - at
100% when everything is working, and the wx is good.

A friend of mine is both a fixed-wing and rotary-wing
instructor in the USA, and a while back he flew with a
doctor in his helicopter. Apparently the doctor was maxed
out in normal conditions. My friend said that he was
dead if he ever tried to fly an auto. Sure enough, the
doctor crashed his helicopter shortly after. Amazingly,
he lived.

What I'm trying to say, is that you need to run your
brain at less than 100% for normal ops. If your brain
is running wide open for normal ops, you are roadkill
if anything bad happens - and sooner or later, it will.

This is important. Figure out how to run your brain
at a very low % cpu utilization, so you have lots left
over.

[iflyforpie]

Ha.... reminds me of the guy I saw with his new-to-him Twin Commanche this summer.

It's got six tanks, and apparently (I was only there for the aftermath) he wanted a specific amount of fuel in each tank. Not mains full, half aux, etc.... like different amounts in each tank so there was a fuel imbalance between engines!

He kept on changing his mind and recalculating and after he finally came to a figure, he said to leave the caps off so he could verify. Well, we don't usually leave the caps off, ever, but sure if you insist. Sure enough, he forgot to put them on and had to be reminded. He forgot again and was reminded a second time.

Then I pull up to the pumps and see this pretty Twin Commanche with one fuel cap off just inboard of the left engine. It had been off for nearly an hour while they went to lunch. At least (hopefully) it would be visible from the pilot's seat.


I like your percent CPU analogy. I always use the de-rated (engine) one. In everything, flying, life, you always want to make sure you've got some extra just in case you need it.

[jump154]

Interesting - and I agree.

I've noticed recently that I don't seem to be as taxed as I was - which has made me worry that I have missed something! Interesting take - in that I'm not missing something, just running more efficiently and therfore there is brain power left - what I'm noticing is the excess capacity. Still, at 170ish hours I'm still very wary of complacency.
Recently got into a new to me (but very simple) aircraft - and bang - up to 100% CPU usage again.

As a good friend of mine says - "Keep some in the tank"

[Colonel Sanders]

wary of complacency

Paranoia is something I try very hard to instill
into my students - as Andy Grove (ex-CEO of
Intel) once famously said, only the paranoid
survive



He could (should) have been talking about flying!

Back to CPU utilization (my apologies for my
technological template, that I push ahead of me
and extrude life through) ... when your CPU is
running at 100%, your computer is sluggish and
will do a poor job of accepting additional load.

NASA once did a study on why airline pilots had
accidents. It's a very good question. Their only
real conclusion was that pilots that learned to fly
at an earlier age, had fewer accidents.

Now onto reading tea leaves. NASA hypothesized
that a pilot that learned to fly at an early age,
needed less of his brain to fly the aircraft, and
when something went wrong, had more % of
his brain left over to deal with the emergency.

Work hard at reducing the percentage utilization
of your brain, to fly an airplane. How you do that
is up to you, but I honestly believe that it is the
key to not having an accident - especially when
things go wrong.

[ScudRunner]

This is good new! I usually operate under normal condition just slightly above the comatose level.

[Old Dog Flying]

Neil//you have just left yourself wide open for a zinger!

Barney

[Shiny Side Up]

Paranoia is something I try very hard to instill
into my students

Its not paranoia if they really are out to get you! Since your airplane is really out to get you, then its just good thinking.

How do you instill paranoia in students though? It seems to be a long learned trait. Hide scorpions behind the sunvisor?

[Colonel Sanders]

Learning factor of Effect

And I think that's all I should say about that, here!

[PointyEngine]

My old instructor once told me to "assume everyone is trying to kill you, it'll keep you alive just a little bit longer". Caught a few things after thinking back to these words...

Paranoia is something I try very hard to instill
into my students

Its not paranoia if they really are out to get you! Since your airplane is really out to get you, then its just good thinking.

How do you instill paranoia in students though? It seems to be a long learned trait. Hide scorpions behind the sunvisor?

[pelmet]

A lot of time went by, and finally they feathered the
right engine, and it came to a stop with the blades
totally coarse pitch. After many, many tries they
were able to restart it, and the lengthy runup continued
for a considerable length of time.

That reminds me of an experience I had while doing multi-training years ago in a Duchess. We ended up with a feathered engine in flight because somehow the instructor thought we had a fire.

Anyways, after a quick inspection back at home base, the instructor started the engine up in feather and I remember it running very rough as it unfeathered itself. I know we do it in flight as well but I always kind of wondered if it was particularly good to just start the engine up in feather while on the ground. Is there any alternative method that maintenance can do to unfeather the engine without starting it up or is there a particular procedure that the pilots can do to minimize that gawd-awful shaking on start or do we just accept it.

[iflyforpie]

If the aircraft has an unfeathering accumulator it usually makes things easier, but other than that, you need the high oil pressure from the prop governor to unfeather, which means running the engine. Yeah, it's hard on it, basically taking an a cold engine at idle and making it pull a vehicle in overdrive.

[Rookie50]

Interesting thread.

2 lines of thought.

One is to reduce, through study, preparation, currency, reduce the % of CPU you require in normal ops.

2, is to recognize your own limitations, as each persons is different, and different at different times due to illness, stress, fatigue, and many other factors.

Interesting thought about brain saturation as it applies to single pilot IFR. I know for me, nice day VFR, pretty low CPU %. IFR, somewhat higher, but with room still, but can degrade with excess fatigue for me.

[Colonel Sanders]

any alternative method that maintenance can do to unfeather the engine without starting it up

I've never tried it, but I suppose you could pull
the top plugs so the engine could spin over easily
then put external power on it (to keep the volts up)
and spin it on the starter.

You would have to be careful to avoid overheating
the starter (which admittedly has a much easier
job with the top plugs out) but you could crank it
in the hope of building some oil pressure.

I am skeptical, but theoretically if you had enough
oil pressure, you could unfeather the prop. Oil
accumulators in airplane really don't provide very
much pressure for very long - they are tiny, compared
to say the offshore oil drilling rig accumulators I used
to work on (e.g. 5,000 psi).

[iflyforpie]

I'm not sure if that would work. Constant speed props need the governor pump to work, which is in the hundreds if not thousands of PSI (the engine oil pump is only the supply, nowhere near enough to move the prop against the feathering spring). The only plus side is that at low RPM, the centrifugal twisting moment and the counterweights aren't opposing the piston as much.

Another possibility is using blade paddles to move the blades back to the pitch locks, but it's pretty easy to damage the propeller if you don't follow manufacturer's instructions to a T.

[Colonel Sanders]

I'm not sure if that would work

I don't think it would either, but perhaps for some
aircraft it might - esp with a lightweight starter that
really ran the RPM up when you cranked it with the
top plugs out.

using blade paddles to move the blades back to the pitch locks

Really risky, unless you know exactly how the hub
is constructed! As you say, without exact instructions
from the prop manufacturer for that exact model of hub,
you will probably do more damage than a feathered start.

[Jonathan Goldsmith]

Student pilots are are instructed to perform lengthy runups. Flying schools know billable flight time starts when the instructor finishes a cup of coffee and walks outside and the costs of air time start when the aircraft leaves the surface of the earth. Good practices such as mag checks while taxiing are discouraged in the name of increasing ground time. Cessna 150's drive to the other end of 10,000' runways because an intersection takeoff with a mile of runway plus a half mile of landable grass is called unsafe. We are up to 5 minutes of post start checks taxi to run up area, taxi to the other side of the run up area because there was room for an aircraft to get behind us and get blown over by our C-150, 5 minute run up, taxi for 2 miles, hold position for an airliner on approach, fly for 27 minutes, about 3 circuits till the instructor has pee some coffee. Total time 55 minutes, billable time 1.0 hours, flying time half that if your lucky.

[Colonel Sanders]

You really are the most interesting man in the world!

[rob-air]

HAHAH that was funny...
Iam paranoid, I swear sometime that 172 has the im gonna kill you look.

All jokes aside, I always tell students that the brain works differently up there. Not to the pilot's advantage.

[Colonel Sanders]

A decent proxy for brain % utilization is the pilot's
voice. When I am flying, and I hear a pilot talking
two octaves above normal, I know he's stressed
and likely at 100% brain utilization.

When I am doing something unusual at the airport,
is it not unusual to hear a very high-pitched voice
from a PPL in an aircraft inbound 5 or 10 miles out,
whom is stressed not only by having to share the
circuit with an aircraft, but an unusual aircraft. Pegs
his stress meter. Brain is now 100% and clanked
up tight, flying straight and level.

I try to relax him by telling him that I will be on the
ground by time he finally arrives at the airport, and
that he couldn't hit me if he tried.

[iflyforpie]

That's why I always have my sexy voice on.... even when I am stressed....

[xysn]

I had an instructor once who was totally unable to ascertain my % utilization and was piling on the instructions and questions until I actually said "I'm sorry I'm overloaded right now" I would really like to get the hang of what you were telling me to do 10 minutes ago"

Tip for FIs - watch for signs of overloading.

[Colonel Sanders]

Two valid responses:

"Standby one", or

"Eject, eject, eject!!"

[New_PIC]

Yes, there were a few times when I was struggling with something and the instructor was talking away about it but I was so busy that I missed 9/10ths of what he was saying. I'm sure that if I wasn't already overloaded I would have taken the time to sort that out with him but right then it was all I could do to fly the plane and prepare for another attempt at whatever it was I was botching up. It eventually worked out.

Another FI tip: feel free to repeat yourself, lots, because it may not be getting through at first.

[Shiny Side Up]

A decent proxy for brain % utilization is the pilot's
voice. When I am flying, and I hear a pilot talking
two octaves above normal, I know he's stressed
and likely at 100% brain utilization.

That's because talking for most people takes up a lot of their processing power. When they get into a situation where they feel they need to talk a lot, and fast, their CPU usage spikes. Old discussion here, how many feel that their ability to broadcast on the radio is their prime defense against colliding with other airplanes. Most people of course listen only about 30% as well as they like to talk, so the straining to listen while their brain is in output mode is difficult. Consequently stress shows up in their voice, they no longer have the processing power to sound like a rational adult, their voice goes into its fight or flight patterns closer derived from their ape anscestors. Not to mention the fact that since they're afraid they're probably just shy of hyperventilating trying to get enough oxygen to the brain to deal with the percieved threat.

Danger Will Robinson!

When I am doing something unusual at the airport,
is it not unusual to hear a very high-pitched voice
from a PPL in an aircraft inbound 5 or 10 miles out,
whom is stressed not only by having to share the
circuit with an aircraft, but an unusual aircraft. Pegs
his stress meter. Brain is now 100% and clanked
up tight, flying straight and level.

Maybe its partly due to the call lettes "Pitts 666" or the fact that the airplane is a Pale horse that's rider is comming to get them. Just sayin' ...

I try to relax him by telling him that I will be on the
ground by time he finally arrives at the airport, and
that he couldn't hit me if he tried.

So instead you should respond with "don't worry, I'm not here for you this week."

[Colonel Sanders]

I was struggling with something and the instructor was talking away about it but I was so busy that I missed 9/10ths of what he was saying

Every flight instructor here (current and future)
should re-read that.

He missed 90% of what the instructor said. That's
a pretty poor yield. As an instructor, work hard on
increasing the % retention of what you tell your students.

Tell them less. Tell them only important stuff - not
chickensh1t. You need to learn to prioritize. So do
they.

With possibly good intentions - however, I remain
darkly suspicious - people pile on crap of dubious
value for the sake of "completeness". Such people
think it is more important to do a bad job of everything
instead of a good job at the important stuff.

Ever wonder why so many people flunk the forced approach?