motorgliders as towplanes

That would not be possible......only "momentary". You can't "keep"
"everything else" constant.

Yes, there would be a "momentary" increase in lift......but......

Glider would experience "acceleration", change in velocity, and or
direction. (Most likely glider would "nose up" (change in direction)
then "slow down" (change in velocity) finally resume steady flight with
greater drag giving steeper glide angle.

Once "stabilized" flight is resumed, vector analysis shows flaps do not
increase lift. Yes, the coefficient of lift has changed but not the
actual lift (other than a really, really tiny reduction due to new flgith
path)

Similar for spoilers

Cookie




At 09:40 20 March 2009, The Real Doctor wrote:
On 20 Mar, 01:15, Bob Cook wrote:

If we draw vector force diagrams of two identical gliders, one with
flaps
extended, and the other with flaps retracted, we can easily see that
"lift" is essentially the same in both cases.

What happens if you extend the flaps on a glider while keeping
everything else (AoA, airspeed) constant?

Ian

In message
, The
Real Doctor writes
On 20 Mar, 07:30, Jim White wrote:
Cookie...are you drinking enough? The weather in your part of the world
must be bad as you do not seem to leave much time for flying.

Dunno where he is, but I'm in Scotland. Need I say more?

I sincerely hope you were flying on the 22nd February. Fantastic wave
day, and a Sunday!

--
Surfer!
Email to: ramwater at uk2 dot net

In the words of Foghorn Leghorn, "That was a joke son, a joke. How come
you're not laughin'?"

Anyway, we have some of the best soaring weather here in Blairstown. Just
check out the OLC!

As you might have noticed my posts are usually in the early morning or
late evening. The middle of my day is filled up with flying! (Lucky me)
But, beyond RAS and flying I have no life at all!

Cookie



At 09:45 20 March 2009, The Real Doctor wrote:
On 20 Mar, 07:30, Jim White wrote:
Cookie...are you drinking enough? The weather in your part of the
world
must be bad as you do not seem to leave much time for flying.

Dunno where he is, but I'm in Scotland. Need I say more?

Ian

On 20 Mar, 12:20, Surfer! wrote:
In message
, The
Real Doctor writes

On 20 Mar, 07:30, Jim White wrote:
Cookie...are you drinking enough? The weather in your part of the world
must be bad as you do not seem to leave much time for flying.

Dunno where he is, but I'm in Scotland. Need I say more?

I sincerely hope you were flying on the 22nd February. *Fantastic wave
day, and a Sunday!

Alas not. The glider is awaiting some work and I don;t normally fly in
the winter anyway.

Ian

You guys have proven 2 fundamental truths.

1) In any engineering discussion. If you don't define terms at the
start, you just chase yourself around in a circle.

2) Pilots don't need to know much about aerodyanmics to fly well.

Oh yeah,

3) Flight instructors explain these things more to make a point than
to be accurate :-)


Todd Smith
3S

On 20 Mar, 13:29, wrote:
You guys have proven 2 fundamental truths.

1) *In any engineering discussion. *If you don't define terms at the
start, you just chase yourself around in a circle.

What, exactly, do you mean by "circle"?

2) *Pilots don't need to know much about aerodyanmics to fly well.

I suspect it only distracts from the task at hand.

3) Flight instructors explain these things more to make a point than
to be accurate :-)

And how. I just wish they'd tell the rest of us what the point is ...

Ian

At 00:45 20 March 2009, Bob Cook wrote:

You are on to something here. Get one of those geo surveys, and fly
your
glider only over areas of higher gravity. This extra gravity will give
your glider extra power, and you will be the best glider pilot!

Well, that should work. The important thing is that you have to find and
use thermals only in *low* gravity areas, and then do your inter-thermal
cruising in the *high* gravity areas. Next best thing to dynamic
soaring.

Jim Beckman

At 19:48 19 March 2009, Martin Gregorie wrote:
On Thu, 19 Mar 2009 13:09:30 -0500, Jim Logajan wrote:

You're claim conflicts with that in the FAA "Pilot's Handbook of
Aeronautical Knowledge":

"Found on many gliders and some aircraft, high drag devices called
spoilers are deployed from the wings to spoil the smooth airflow,
reducing lift and increasing drag."

Printing it in some official or semi-official publication doesn't make
it
right.

But it *does* make it the right answer to the written test when that test
is given by that same authority. For the test, concentrate not on what is
necessarily true, but on what the FAA wants for an answer. After the
written is out of the way, just learn to fly the aircraft.

Jim Beckman

The Real Doctor wrote:
On 20 Mar, 01:39, Doug Hoffman wrote:

And lift(as we are using the term) without gravity is not possible.

Aircraft in a 90 degree bank can still produce lift ...

Without gravity how will you get the glider into a bank (or even to
move)? Answer = not possible.

Regards,

-Doug

"The Real Doctor" wrote in message
...
On 20 Mar, 01:15, Bob Cook wrote:

If we draw vector force diagrams of two identical gliders, one with flaps
extended, and the other with flaps retracted, we can easily see that
"lift" is essentially the same in both cases.

What happens if you extend the flaps on a glider while keeping
everything else (AoA, airspeed) constant?

Ian

I have really been trying to avoid getting involved in this thread. It seem
too much like "I'm smart and you're not". However, I just want to point out
that to maintain the same AoA while lowering the flaps will require the
pilot to lower the nose of the aircraft. This is due to the change to the
wing's effective angle of incidence.

I really question if it is posible to lower to flaps while keeping the AoA
and airspeed constant. I know that maintaining a constant airspeed of 50
kts while lowering the flaps to 90 degrees on my HP-14 results in a 45+
degree nose down attitude. I am positive the wing's AoA changes while doing
so.

Respectfully,

Wayne
HP-14 "6F"
http://www.soaridaho.com/Schreder