AoA keep it going!

Ralph Jones wrote:
"Fly attitude and don't chase the airspeed" really means "fly AoA and
don't chase the airspeed", but if you don't have an AoA indicator, you
have to use the attitude as a substitute for AoA. And it's a
second-rate substitute.

Please pardon me if I sound a bit cranky, but how can attitude be a
"second-rate substitute" for something that we don't even have?

And what would a "first-rate substitute" be?

Not a single poster here has flown with an AOA meter in their glider,
except a few using yarn taped to the side of their canopy. Is that what
we should be using instead of attitude and airspeed?

"Show me the money".

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric Greenwell wrote:
Not a single poster here has flown with an AOA meter in their glider,
except a few using yarn taped to the side of their canopy. Is that what
we should be using instead of attitude and airspeed?

Actually, I have flown with the factory supplied AoA meter (differential
pressure) in my DG-600, but I could never get the darn thing calibrated
properly...

Marc

Marc Ramsey wrote:
Eric Greenwell wrote:
Not a single poster here has flown with an AOA meter in their glider,
except a few using yarn taped to the side of their canopy. Is that
what we should be using instead of attitude and airspeed?

Actually, I have flown with the factory supplied AoA meter (differential
pressure) in my DG-600, but I could never get the darn thing calibrated
properly...

Bummer. I'm still hoping we'll hear from some pilots with the newest DG
80x gliders, which has it as standard equipment (I think that's right...).

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Marc Ramsey wrote:
Eric Greenwell wrote:
Not a single poster here has flown with an AOA meter in their glider,
except a few using yarn taped to the side of their canopy. Is that
what we should be using instead of attitude and airspeed?

Actually, I have flown with the factory supplied AoA meter (differential
pressure) in my DG-600, but I could never get the darn thing calibrated
properly...

Marc

One common problem with many arguments (not just on RAS!) is that people
compare the status quo with an idealized world, and conclude that the
status quo is flawed and must be changed. It seems to me this may be
occurring in the AoA discussion -- many posters have compared a
perfectly functioning AoA indicator with our slow and inaccurate ASIs,
and concluded that AoA indicators are better. But perhaps in the real
world AoA indicators on gliders would be even less accurate than ASIs?

Greg Arnold wrote:
Marc Ramsey wrote:
Eric Greenwell wrote:
Not a single poster here has flown with an AOA meter in their glider,
except a few using yarn taped to the side of their canopy. Is that
what we should be using instead of attitude and airspeed?

Actually, I have flown with the factory supplied AoA meter
(differential pressure) in my DG-600, but I could never get the darn
thing calibrated properly...

Marc

One common problem with many arguments (not just on RAS!) is that people
compare the status quo with an idealized world, and conclude that the
status quo is flawed and must be changed. It seems to me this may be
occurring in the AoA discussion -- many posters have compared a
perfectly functioning AoA indicator with our slow and inaccurate ASIs,
and concluded that AoA indicators are better. But perhaps in the real
world AoA indicators on gliders would be even less accurate than ASIs?

Insufficient evidence. Mine was a 17 year old analog electronic device
hooked up to 17 year old plumbing. It sometimes seemed to work, but not
consistently.

Marc

On Dec 22, 10:36*pm, Greg Arnold wrote
One common problem with many arguments (not just on RAS!) is that people
compare the status quo with an idealized world, and conclude that the
status quo is flawed and must be changed. *It seems to me this may be
occurring in the AoA discussion -- many posters have compared a
perfectly functioning AoA indicator with our slow and inaccurate ASIs,
and concluded that AoA indicators are better. *But perhaps in the real
world AoA indicators on gliders would be even less accurate than ASIs?

Greg, I don't see it that way. I see the basic argument is about AoA
vs airspeed as the more accurate/desirable control instrument for
certain phases of flight (assuming equally good instrumentation for
the AoA and airspeed).

As far as instrument accuracy, AoA and airspeed are fundamentally
different, with different ways to be measured. You define the level
of accuracy you want, and design the sensor and display accordingly.
This is not rocket science - AoA indicators have been around since
before the airspeed indicator, and was probably considered easier to
measure at first!

A side discussion relates to the fact that airspeed indicators are
universal, while AoA sysems are expensive and not common in gliders.
While the appropriate technology is simple and would be easy to
incorporate in a glider while it is being built (a few sets of
pressure ports on each wing, connected to a microprocessor and
display) the current cost is in the $1500 range - plus installation -
so I doubt we'll be seeing a lot of them in cockpits soon. But
picture this: You have the plumbing installed while your new glider
is being built (some tubing - not a lot of cost there, basically it's
another multi-orifice static system in the wings). Then the latest
SN-99 or LX-9999 has the software and connectors builtin (adds $500 to
the box). It might start showing up - first in top of the line
motorgliders, then filtering down.

I fail to understand why looking at ways to make flying more efficient
and safer causes such a defensive response! But then, the same thing
probably happened when the first electric varios came out - "what's
wrong with our PZL? Dont need no stinkin battery, works just fine!
Next you'll want it to make noise!"

Then there was the great GPS debate...or even radios!

Kirk

On Sun, 23 Dec 2007 03:23:59 GMT, Eric Greenwell
wrote:

Ralph Jones wrote:
"Fly attitude and don't chase the airspeed" really means "fly AoA and
don't chase the airspeed", but if you don't have an AoA indicator, you
have to use the attitude as a substitute for AoA. And it's a
second-rate substitute.

Please pardon me if I sound a bit cranky, but how can attitude be a
"second-rate substitute" for something that we don't even have?

And what would a "first-rate substitute" be?


You could probably design one, but okay, I concede the grammatical
point. Let's put it this way: The ASI is to a good AoA meter as Hormel
Potted Meat Food Product is to Underwood Deviled Ham.

rj

Ralph Jones wrote:
On Sun, 23 Dec 2007 03:23:59 GMT, Eric Greenwell
wrote:

Ralph Jones wrote:
"Fly attitude and don't chase the airspeed" really means "fly AoA and
don't chase the airspeed", but if you don't have an AoA indicator, you
have to use the attitude as a substitute for AoA. And it's a
second-rate substitute.
Please pardon me if I sound a bit cranky, but how can attitude be a
"second-rate substitute" for something that we don't even have?

And what would a "first-rate substitute" be?


You could probably design one, but okay, I concede the grammatical
point. Let's put it this way: The ASI is to a good AoA meter as Hormel
Potted Meat Food Product is to Underwood Deviled Ham.

You better not be disrespecting Spam! As a 4th generation Hawaiian, I'd
have to hunt you down and hurt you, probably by showing you a video
purchased at the Spam Museum. Of course I've been there! What else can
you do when it rains during a contest at Albert Lea?

Hmmm, am I going to have to explain all this?

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org