How to tell my instructor to increase glidespeed with headwind?

Ok, my instructor did a simulated engine failure in the pattern; winds
were around 20kts in the air and 13kts on the ground. Did everything
perfectly; however after we took off again, he told me to maintain 65
kts next time, and I totally disagreed.
The manual says 65 kts for best glide speed; however that is in calm
air. As a glider person, I know adding about 1/2 the headwind component
will give the greatest distance.
After the flight I pulled up the Glider Flying handbook online and it
says:

"...it is apparent that flying a faster airspeed as the headwind
increases will result in the greatest distance over the
ground. If this is done for the polar curves from many
gliders, a general rule of thumb is found, namely, add
half the headwind component to the best L/D for the
maximum distance."

But even after telling him that he said that doesn't apply to power
planes, also saying that manuals never give best glide, and there has
to be a reason for that.

Do you guys have any ideas on how I can really convince him? Any good
sources?

Thanks!
-Nik

On 1 Nov 2006 15:22:16 -0800, "Nik" wrote:

Do you guys have any ideas

Yes: Run, don't walk away from that instructor.

Tobias

One simplified way would be to say you want to spend less time in the
headwind. Oversimplified, but it might at least get him to consider it.

Might use some simple math with convenient figures to prove it to him.

Best glide isn't in the books because it varies with weight and, as you can
see, wind conditions.

If you can't get it through to him, take the previous posters advice...run.

mike



"Nik" wrote in message
ups.com...
Ok, my instructor did a simulated engine failure in the pattern; winds
were around 20kts in the air and 13kts on the ground. Did everything
perfectly; however after we took off again, he told me to maintain 65
kts next time, and I totally disagreed.
The manual says 65 kts for best glide speed; however that is in calm
air. As a glider person, I know adding about 1/2 the headwind component
will give the greatest distance.
After the flight I pulled up the Glider Flying handbook online and it
says:

"...it is apparent that flying a faster airspeed as the headwind
increases will result in the greatest distance over the
ground. If this is done for the polar curves from many
gliders, a general rule of thumb is found, namely, add
half the headwind component to the best L/D for the
maximum distance."

But even after telling him that he said that doesn't apply to power
planes, also saying that manuals never give best glide, and there has
to be a reason for that.

Do you guys have any ideas on how I can really convince him? Any good
sources?

Thanks!
-Nik

"Nik" wrote in message
ups.com...
Ok, my instructor did a simulated engine failure in the pattern; winds
were around 20kts in the air and 13kts on the ground. Did everything
perfectly; however after we took off again, he told me to maintain 65
kts next time, and I totally disagreed.
The manual says 65 kts for best glide speed; however that is in calm
air. As a glider person, I know adding about 1/2 the headwind component
will give the greatest distance.
...
But even after telling him that he said that doesn't apply to power
planes, also saying that manuals never give best glide, and there has
to be a reason for that.

Do you guys have any ideas on how I can really convince him? Any good
sources?

You might try pointing him to
http://www.av8n.com/how/htm/power.ht...nd-penetration.

Or you might try to convince him to let you fly it both ways and see which
way gets you further.

If that doesn't persuade him, you might decide do it his way when you fly
with him, and do it the right way at other times.

--Gary

On 1 Nov 2006 15:22:16 -0800, "Nik" wrote in
. com:

But even after telling him that he said that doesn't apply to power
planes, also saying that manuals never give best glide, and there has
to be a reason for that.

Go to the Chief Pilot at the FBO, and ask him to explain it to your
CFI.

Remember what you're trying to do he get ready for/pass a checkride!

Barry Schiff recently wrote an article about how he was being checked
out for a rental and he set his speed to 55kts during the engine-out
exercise because that is the "rate of least descent" for an airplane
with a best glide speed of 67 knots. He was trying to set the "least
descent" speed to give him time to choose an adequate landing site at
which time he would have set the nose for the best glide speed. While
Mr. Schiff was right, he got gigged on it and found himself having to
prove himself and educate an instructor instead of getting the sign-off
and an airplane for an afternoon.

He'd have been much better off, for his own purposes, to have been
selfish, done as the instructor expected and then rent the airplane. I
suspect you might want to think the same way since you're not in a
position of credibility as a student and this particular piece of
knowledge is probably not universally taught to instructors of powered
aircraft. I'm also betting you are correct and that the rules of
physics do not change just because you add 300 lbs of dead weight and a
motionless propeller to the front of the glider. But, what is it you're
trying to do? Prove something he doesn't know? Or are you more
interested in proving your competence by his standards?

In other words, for what you're trying to get done, please the
professor first. Engage in the debate after you get your license. Odds
are that you'd have the same tough sell in front of you if you attempt
the same argument during your checkride. You can prove you're right
later.

Does that seem sensible?

Humbly,

Greg Chapman



Nik wrote:


Do you guys have any ideas on how I can really convince him? Any good
sources?

Thanks!
-Nik

writes:

Barry Schiff recently wrote an article about how he was being checked
out for a rental and he set his speed to 55kts during the engine-out
exercise because that is the "rate of least descent" for an airplane
with a best glide speed of 67 knots. He was trying to set the "least
descent" speed to give him time to choose an adequate landing site at
which time he would have set the nose for the best glide speed. While
Mr. Schiff was right, he got gigged on it and found himself having to
prove himself and educate an instructor instead of getting the sign-off
and an airplane for an afternoon.

He'd have been much better off, for his own purposes, to have been
selfish, done as the instructor expected and then rent the airplane. I
suspect you might want to think the same way since you're not in a
position of credibility as a student and this particular piece of
knowledge is probably not universally taught to instructors of powered
aircraft. I'm also betting you are correct and that the rules of
physics do not change just because you add 300 lbs of dead weight and a
motionless propeller to the front of the glider. But, what is it you're
trying to do? Prove something he doesn't know? Or are you more
interested in proving your competence by his standards?

In other words, for what you're trying to get done, please the
professor first. Engage in the debate after you get your license. Odds
are that you'd have the same tough sell in front of you if you attempt
the same argument during your checkride. You can prove you're right
later.

Does that seem sensible?

No, because the same instructor may misinform others who do not have
the benefit of other sources of information, and someone may be
injured or killed as a result of his misinformation.

Correct the instructor if he is wrong. If this creates an obstacle to
attaining your own objectives, find another instructor. But don't
just leave him to put other students in danger.

--
Transpose mxsmanic and gmail to reach me by e-mail.

"Nik" wrote in message
ups.com...
Ok, my instructor did a simulated engine failure in the pattern; winds
were around 20kts in the air and 13kts on the ground. Did everything
perfectly; however after we took off again, he told me to maintain 65
kts next time, and I totally disagreed.
The manual says 65 kts for best glide speed; however that is in calm
air. As a glider person, I know adding about 1/2 the headwind component
will give the greatest distance.
After the flight I pulled up the Glider Flying handbook online and it
says:

"...it is apparent that flying a faster airspeed as the headwind
increases will result in the greatest distance over the
ground. If this is done for the polar curves from many
gliders, a general rule of thumb is found, namely, add
half the headwind component to the best L/D for the
maximum distance."

But even after telling him that he said that doesn't apply to power
planes, also saying that manuals never give best glide, and there has
to be a reason for that.

Do you guys have any ideas on how I can really convince him? Any good
sources?

Thanks!
-Nik


It has been a while since this happened, but my Instructor when I was going
for my PP-ASEL told me 70 was best glide in the C172 but I knew the manual
said 65, I showed him it one day and he said he was wrong and glad I pointed
it out. So if you show him info "from a higher power" he will listen.

--------------------------------------------------
DW

Mxsmanic wrote in
:

Correct the instructor if he is wrong. If this creates an obstacle to
attaining your own objectives, find another instructor.

You're kidding, right?

wrote in message
ups.com...
[...]
In other words, for what you're trying to get done, please the
professor first. Engage in the debate after you get your license. Odds
are that you'd have the same tough sell in front of you if you attempt
the same argument during your checkride. You can prove you're right
later.

Does that seem sensible?

That advice makes some sense for someone in Schiff's position. I don't
agree that it makes sense for a student who is actually hiring his
instructor to teach him something.

In this case, the student knows the answer, understands the answer, and is
confident in that knowledge. But what if something else comes up in which
the instructor is *also* mistaken, and in which the instructor refuses to
consider the possibility that he's wrong? If it turns out in that situation
that Nik either doesn't know for sure what the right answer is, or doesn't
even have reason to suspect the instructor is wrong, then Nik will be at a
disadvantage, being taught by an instructor who should not be instructing in
the first place.

I have had situations with instructors in which I was only to fly with the
instructor once, for the purpose of showing some competence in an airplane
or type of flight or something like that and in which the instructor said or
did something that I disagreed with (and most of the time, it turned out I
was right ). In those situations, you're right...you just go with the
flow, and let the instructor have his way (assuming it's not a safety of
flight issue, of course...I had to terminate an IPC prematurely, because of
an instructor who was so bad, he was interfering with the safety of the
flight).

But for someone with whom you expect to have an on-going relationship, even
if for a few lessons but especially for a primary student, it's important to
a) resolve every single issue to the point of truthful consensus, and b) to
know that you can trust your instructor to not tell you something is
absolutely true when in fact it's known to be absolutely false.

I don't know whether the flight in question was a one-time thing, or is part
of on-going instruction that Nik is taking from the instructor, but in
absence of that knowledge, I think it's important to make sure that no one
thinks it's okay to just let an instructor say wrong things, especially if
one is doing more than just the one flight with that instructor.

Pete