What's your favorite youtube speedpass?

here's mine:

http://www.youtube.com/watch?v=2S7T81LbvIs

and another great one!

http://www.youtube.com/watch?v=K2GVtGdsXrM

On Thursday, January 23, 2014 7:08:19 AM UTC-6, Andrew Brayer wrote:
here's mine:



http://www.youtube.com/watch?v=2S7T81LbvIs

Nice pass!

A question for all you aero majors out the when pulling up at high speed, should you lead with the flaps, or follow with them?

In this vid, pilot pulls, then lowers flaps after speed has dropped. My understanding is that it is more efficient to lower flaps (from cruise to zero, then positive as you slow) during the pull, and my experience somewhat bears that out (higher alt gain with a good pull and simultaneous flaps).

I know that is what happens when you pull on the stick in an F-16! (Well, actually, the leading edge comes down, but you know what I mean...).

And don't you just love guys who park their glider on the approach end before being ready to launch?

Cheers,

Kirk
66

My second favorite: http://www.youtube.com/watch?v=RZIYmHnK_r8

MY FAVORITE: https://vimeo.com/31524242

:-)

On 23/01/14 13:08, Andrew Brayer wrote:
here's mine:

http://www.youtube.com/watch?v=2S7T81LbvIs


http://www.youtube.com/watch?v=qqlGip0ff7s

On Thursday, January 23, 2014 9:52:53 AM UTC-5, Tom Gardner wrote:
On 23/01/14 13:08, Andrew Brayer wrote:

here's mine:



http://www.youtube.com/watch?v=2S7T81LbvIs





http://www.youtube.com/watch?v=qqlGip0ff7s

yeahhhhhh. that one is pretty good... like really good.

On Thursday, January 23, 2014 9:18:36 AM UTC-5, kirk.stant wrote:


A question for all you aero majors out the when pulling up at high speed, should you lead with the flaps, or follow with them?



I've run #s for my ASW-20B at full gross weight, 90 KIAS (cruising at Hobbs, on a nice day :-)).

It says if you pull the stick in #1 flap, you can pull about 2g maximum before onset of separation. If you lead with the flap, you can get to 3g. Considering that the first G is committed to opposing gravity, this is a 2x difference in vertical acceleration, really huge. Sadly, I did not have this figured out when I was at Hobbs last Summer and it caused me a great deal of frustration. Here in the East, we never have to make big pulls like that, so I generally just pull (gently) with the stick.

When hooning around close to the ground or anything else you don't want to hit, I'd suggest leaving the flap handle alone.

Evan Ludeman / T8

nice long low one.

http://www.youtube.com/watch?v=N1sta1GMQxM

On 1/23/2014 7:18 AM, kirk.stant wrote (w. some snippage):


http://www.youtube.com/watch?v=2S7T81LbvIs

Nice pass!

A question for all you aero majors out the when pulling up at high
speed, should you lead with the flaps, or follow with them?

In this vid, pilot pulls, then lowers flaps after speed has dropped. My
understanding is that it is more efficient to lower flaps (from cruise to
zero, then positive as you slow) during the pull, and my experience
somewhat bears that out (higher alt gain with a good pull and simultaneous
flaps).


Neither lead nor follow?

Here's an attempt at one of those potentially worthless - in the sense that
for all practical purposes it can be neither effectively measured nor
implemented in real time - responses that might just shed some theoretical
light upon one's flying techniques...

If we - for the purposes of a pullup - define "efficiency" as "least
aerodynamic drag possible per time instant" (since both drag and gravity
oppose the ship's ability to trade kinetic energy for height) then the answer
to the question obviously (!) is the flaps should be placed in whatever
position minimizes aerodynamic drag for that instant's speed...think polar.

Complicating factors almost certainly include time and flap position, since
for any given (ever-increasing) amount of flap deflection (below the
separation angle of attack) the wing section can generate greater total lift,
which for a fixed-weight condition will be proportional to "wing developable
G." So, will a shorter time at high G (and drag) - meaning a shorter time to
change pitch angle from (say) "descending through pitched up" - result in
greater speed at the start of the ascent than a "theoretically most
aerodynamically efficient (longer-in-time) configuration" through the same
angular change?

I don't know, but my suspicion is aerodynamic efficiency would trump. In any
event, if we take "the rapid pitch-up" scenario to an extreme, various
fighters can demonstrate that a rapid pitch-up is a great way to bleed energy
and speed (think "the cobra maneuver").

As foe Joe Glider Pilot, this is a great example of one (ideally, many)
test(s) being worth ten thousand considered opinions! Kids, don't do this test
in the pattern...

Bob - it's still winter... - W.

Me in my Genesis 2 - Water Dump
http://youtu.be/ZQWhEjwRIMk