Spin to impact AOA

On Jan 13, 5:33 pm, wrote:
Mat, training yourself to use an AOA indicator takes about 30 seconds - it's
really obvious. Training to use the ASI for pitch attitude without
reference to the visible horizon takes many hours of intensive training and
even then most pilots don't do it well.

AOA indicators are about reducing information overload, not increasing it.
An AOA indicator IS a stall warning with far greater resolution. The EASY
way to fly is with an AOA. The HARD way is to do without it.

.

Bill Daniels

So, we are talking about pitch attitude control without reference to
the visible horizon. In that situation how do we control roll and
yaw?

The same way as we control roll and yaw in normal flight, since we
don't need a horizon to do this. Roll can be detected as long as there
is a reference in the distance we can see we are rolling with respect
to, and yaw can be detected using a yaw string or slip ball. Balanced
bank will always produce a turn, which can of course be seen as the
reference surface moving past the nose.

[Not answering directly to this poster]

Consider the yaw string. How much simpler it is and
how much quicker it responds than the ball slip/skid
indicator. An proper AoA indicator should behave just
like the yaw string, and would give better information
than the ASI. Arguments that we should ignore AoA
possibilities are effectively the same as saying we
should go back to the ball. It can be done, but it
is nowhere near as easy to fly with as the yaw string.

If a good, reliable, effective, and inexpensive one
is developed, I'll buy it. I've toyed with strings
on the side of the canopy and I like what I see.

At 00:36 14 January 2008, wrote:


Mat, training yourself to use an AOA indicator takes
about 30 seconds - it=
's
really obvious. =A0Training to use the ASI for pitch
attitude without
reference to the visible horizon takes many hours
of intensive training an=
d
even then most pilots don't do it well.

AOA indicators are about reducing information overload,
not increasing it.=

An AOA indicator IS a stall warning with far greater
resolution. =A0The EA=
SY
way to fly is with an AOA. =A0The HARD way is to do
without it.

.

Bill Daniels

So, we are talking about pitch attitude control without
reference to
the visible horizon. In that situation how do we control
roll and
yaw?

By saying, 'Attempting to use aircraft attitude (deck
angle) without a
reliable horizon
will get you killed real fast' do you mean attempting
to CONTROL
attitude, or attempting to DETERMINE aircraft attitude?
Matt

wrote in message
...


Mat, training yourself to use an AOA indicator takes about 30 seconds -
it's
really obvious. Training to use the ASI for pitch attitude without
reference to the visible horizon takes many hours of intensive training
and
even then most pilots don't do it well.

AOA indicators are about reducing information overload, not increasing it.
An AOA indicator IS a stall warning with far greater resolution. The EASY
way to fly is with an AOA. The HARD way is to do without it.

.

Bill Daniels

So, we are talking about pitch attitude control without reference to
the visible horizon. In that situation how do we control roll and
yaw?

I wrote a confusing line. It should have said "controlling AOA with the ASI
and no relaible horizon is difficult."

By saying, "Attempting to use aircraft attitude (deck angle) without a
reliable horizon
will get you killed real fast" do you mean attempting to CONTROL
attitude, or attempting to DETERMINE aircraft attitude?

Does it matter? If you can't detemine attitude, you can't control it.

Bill D



Obviously, if you can't DETERMINE attitude, you can't CONTROL it.

So, we are talking about pitch attitude control without reference to
the visible horizon. *In that situation how do we control roll and
yaw?

The same way as we control roll and yaw in normal flight, since we
don't need a horizon to do this. Roll can be detected as long as there
is a reference in the distance we can see we are rolling with respect
to, and yaw can be detected using a yaw string or slip ball. Balanced
bank will always produce a turn, which can of course be seen as the
reference surface moving past the nose.- Hide quoted text -


A reference in the distance we can see we are rolling with respect to
is, in my expeience, a horizon. It may not be THE horizon but is
sufficient to control the aircraft both in pitch and roll. I think
Bill is trying to make the point that an AOA indicator would be useful
when there is NO horizon.

On Jan 13, 7:19*pm, "Bill Daniels" bildan@comcast-dot-net wrote:
wrote in message

...







Mat, training yourself to use an AOA indicator takes about 30 seconds -
it's
really obvious. Training to use the ASI for pitch attitude without
reference to the visible horizon takes many hours of intensive training
and
even then most pilots don't do it well.

AOA indicators are about reducing information overload, not increasing it.

wrote:
So, we are talking about pitch attitude control without reference to
the visible horizon. In that situation how do we control roll and
yaw?
The same way as we control roll and yaw in normal flight, since we
don't need a horizon to do this. Roll can be detected as long as there
is a reference in the distance we can see we are rolling with respect
to, and yaw can be detected using a yaw string or slip ball. Balanced
bank will always produce a turn, which can of course be seen as the
reference surface moving past the nose.- Hide quoted text -


A reference in the distance we can see we are rolling with respect to
is, in my expeience, a horizon. It may not be THE horizon but is
sufficient to control the aircraft both in pitch and roll. I think
Bill is trying to make the point that an AOA indicator would be useful
when there is NO horizon.

We could call it something catchy, like an "artificial horizon"! Well,
maybe that's a simple way to get an attitude indicator that's
commercially available for a $1000 or so, solid state so power
consumption is low, and easily installed. It might indicate the AOA
accurately enough in steady flight for performance optimizing. Anyone
tried it?

--
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

On 13 Jan, 19:52, "Bill Daniels" bildan@comcast-dot-net wrote:
"Ian" wrote in message

Surely most pilots - after their first few flights - are capable of
hitting and maintaining a desired speed as shown on the ASI?

If you think it's easy, borrow an instrument training hood that blocks your
view of the horizon and give it a try. Only in a 2-seater with a safety
pilot, of course.

Flying without any visual attitude indications is not the same as
flying without a horizon. If anything is visible over the nose it's
possible to use for feedback on changes in nose position, if not
absolute values. In fact, I suspect that that is how most of us do it:
using attitude /change/ in combination with ASI to hit a target speed.
Very few glider pilots fly without any external reference at all.

If that's what you were saying, and I've misunderstood, I'm sorry!

So why don't we all have them?

Damn good question.

And ... ?

Ian

On 13 Jan, 22:15, Eric Greenwell wrote:

1. Which of the commercially available AOA indicators is most suited to
a glider?

2. Who is planning to put one in their glider?

3. How do they deal with flaps?

Ian

On 14 Jan, 01:19, "Bill Daniels" bildan@comcast-dot-net wrote:

Does it matter? If you can't detemine attitude, you can't control it.

Hmm. Philosophical question, maybe, but it's perfectly possible to
control attitude while only knowing airspeed, as my friends who fly in
cloud using ASI and T&S do ...

Ian

Ian wrote:

Surely most pilots - after their first few flights - are capable of
hitting and maintaining a desired speed as shown on the ASI?


Yes, when they have nothing more pressing to think about. and as long
the ASI tells them what they think it should be telling them. Flying a
sailplane is about as easy as flying gets, and yet there are a
half-dozen times a year in the US when it is too much, under the
circumstances, for the involved pilots and they meet an untimely end.

We should all fly more. The accident numbers might go up, but I think
the rates would go down.


Jack