Fergus Kyle
Joined: 03 Jun 2007
Posts: 291
Location: Burlington ON Canada
|
 Posted: Wed Aug 06, 2008 6:54 am Post subject: Stalling and AoA's |
 |
|
Cheers,
I noted the remarks of Mark Burton and others on the topic and agree
that some sort of approach warning to stall might be applicable -
particularly if the headstrong types omit the stall strip in favour of
slower stall angle.
One item keeps gnawing at me from the standpoint of failures to
maintain flying 'speed' and the accidents resulting. That is, that both
wings need not stall at the same angle - in fact most wing stalls occur
one-wing-early because of inaccuracies/irregularities in the shape of each
pinion. When testing/researching the stall, it is vital to find which wing
is the early cause, and why it's vital. This would apply especially to us
who built our own. Where is your AoA?
When approaching the stall, care must be taken to keep the ball in
the middle in order that both wings come close to seeing the same air.
Otherwise, which wing stalls first depends upon which is slowest - that is
in co-ordinated flight,
As soon as you wobble the rudder, you yaw the wings unequally and
the slowest wing 'wins'. At this point you have hobbled the AoA's ability to
predict the outcome. This can be due to improper attention on finals, a loss
of centerline approach, or at the request of observers.
This latter reminds me of the mishaps at Oshkosh, where tension
amongst tyros is high on final and adherence to instructions paramount.
There we are on final turn - maybe lots of bank to prevent overshooting the
centerline, and the approach controller calls for a 'wiggle' or a tailwag.
It's understandable to ignore the co-ordination for a split-second and obey.
At that instant, one wing is slower than the other, and keenness to obey
might add an extreme note.
Oh-oh. Low speed, stress, low altitude, bank and unco-ordinated
flight [don't forget gusty wind]. All these add up to trouble and whatever
device warns of stall is only partly useful. Reliance upon devices instead
of wariness can be dangerous.
Ferg
Europa A064
PS: And we never discussed inaccuracies in the initial set-up of the
device........
| | - The Matronics Europa-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Europa-List |
|
|
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
