|| Chapter 54 NEWS
Volume 43, Issue 10
will be held on
Time 7:00 pm Social
7:30 pm Program
Christ Lutheran Church, Lake Elmo MN
(two Blocks South of Twin Points)
Bill asked if I would insert a few comments for him this month. They will
be few and not as eloquent as you have been seeing.
First, a reminder of upcoming meetings. The chapter officers will meet
next Wednesday evening in Jim Anderson's Hangar at 7:00 p.m. The monthly
chapter meeting is Monday the 9th. Please check the web page for location.
I believe that is still up in the air.
A couple reminders as we get ready for Winter. (it's hard to admit it
is coming) Jerry Sarracco will be organizing the highway cleanup in a
couple weeks. I won't say it's necessarily fun, but, it isn't bad. Sign
up, come early, have a donut and many hands get it done in a hurry.
Let's take the next few weeks to get in a some extra "young
eagle" rides. What would it take, on each one of our parts, to have a
good representation in the EAA magazine listing those that have met the
goal. Check with Al K. if you need some names. Also, give Al names if you
have suggestions and can not get them.
Pass along ideas you may have for a meeting place - short and long
range. Also, I'm sure that many have shared needs and others have offered
a hand to those impacted by the storm's destruction. We may want to spend
a few minutes, at the next meeting, discussing how those "needs"
and "helps" can be matched up. Think about it. Have a good
Dan Parker Vice Prez EAA Chapter 54
|Treasurerís Report: 9/28/2000
Building Fund $2,836.99
No activity this month
This was provided by member Art Edhlund, who got it from his son Paul,
who got it from .... It supposedly came from a Concord Pilot.
Concorde's low speed aerodynamics are a bitch. She is on the backside of
the drag curve until she's up to a least 250 - 300 knots. Until she
reaches a sensible speed she is clawing her way into the sky in a way that
requires vast amounts of power. Without the huge power of those wet
Olympus engines, she would not be able to get up to the sort of speed that
can sustain controlled flight. She would just wallow in a horrible low
speed/high drag corner of the envelope. In the event of an engine failure
on takeoff, she has an ample reserve of excess power to safely get
airborne and accelerate to a good cruise climb speed, but trying to
accelerate to a good speed on only two engines with the Dunlops dangling
in the breeze would be a bitch. Then factor in the effect of the massive
fire gushing from the collector tank and toasting the inboard elevon and
you have a fiendish nightmare of a control problem. The problem of being
on the wrong side of the drag curve is that at these low speeds the power
required INcreases with lower airspeed. In such a flight regime the only
way to get the extra airspeed is to lower the nose and try to convert
altitude for airspeed. Obviously this in not possible at the 200' of
altitude which was as high as AF4590 managed
in her two minute flight. It's a classic gotcha. Not enough power to get
enough speed to be able to require less power.
Once flying she may be a babe, but how close to the edge is she on takeoff
?? The wing is optimized for supersonic flight and is really not very
efficient at low subsonic speeds. Most normal airliners need less thrust
to fly at 250 knots than at 350 knots. Not so with the Concorde. At the
very high angles of attack which are involved in the
initial climb out, the wing is extremely close to the stall, much, much
more than a conventional wing.
One of the clever tricks which the aeronautical engineers devised for the
Concorde was the deliberate introduction of vortex flow over the wing to
generate a controlled separation of the airflow from the boundary layer.
The S-shaped planform of the leading edge of the wing is not an aesthetic
thing. It is a clever trick to generate a "friendly"
vortex which energizes the air over the top of the wing and creates what
is called "vortex lift." There are a couple of very unforgiving
characteristics inherent in the delta configuration. The wing tends to be
speed unstable. A conventional wing/tail configuration has a stable
tendency to regain a trimmed speed in the event of a slight disturbance
such as turbulence or a wee nudge on the control column. A delta, such as
Concorde, Mirage, Vulcan, etc. tends to diverge from a trimmed speed. This
makes it much more difficult to maintain an optimum angle of attack,
particularly at low speeds.
Another unpleasant characteristic is that she tends to pitch UP at the
stall, unlike a normal configuration which is designed to pitch down at
the stall. Of course, pitching up makes the stall even worse. There's more
bad news at the stall !! To push the nose down in order to gain more speed
and get away from the stall, the pilot lowers the elevons. This has the
effect of increasing the effective camber of the wing, which in effect
increases the angle of attack which is causing the stall in the first
place. It's a classic gotcha.
The eyewitness reports of the Concorde rearing up onto it's tail before
sliding down into the Hotel is a classic description of a delta wing
stalling. The romantic nonsense about the pilot pulling up to fly over the
hotel is just journalistic fantasy. The handling pilot was doing his best
to keep the aircraft airborne by finessing the pitch angle to wring every
gram of lift out of the wing in a desperate attempt to go the extra mile
or two and get the aircraft to LeBourget. The ghastly situation which the
three-man crew faced on that flight deck is enough to give anyone the
heebie-jeebies. They did their best, but were completely overwhelmed by
The part of the story which I just do not understand is : Why did the ATC
Tower wait so long before telling the crew that their arse was on fire ??
|CALENDAR of EVENTS
1 FlyIn Breakfast at EAA in EauClaire
means Clear Water, …clair means Puts Fat On Hips)
4 7:00 pm Board of Directors meet at Jim
9 7:30pm Chapter 54 Gathering, maybe at the
Church in Lake Elmo.
From the Editor
The Ascension Flyers lost a hangar and a Citabria. Alex Buga lost a
C-150 and found a Beech Skipper. Kelly Anderson bought a Citabria. There
are a lot of things going on.
I have spent days working on getting my hangar ready for winter. I have
worked every day except for a three day vacation to Duluth with my wife
and son, and a three day fly-in for antiques with my wife and Fairchild.
I have not been out to even look around. There must have been a
thousand interesting things that have occurred in the past month, that
would be of interest to our members.
If you know of something that would be of interest to more than three
members, please let me know. You can reach me through the US Mail, at the
Chapter address, or via the phone at 651-430-9178, or via e-mail at
|EAA Chapter 54 is located at 3275 Manning Ave. N. Suite
#7, Lake Elmo, MN 55042
EAA Chapter 54 NEWS Published monthly by Chapter 54 of the Experimental
Aircraft Association (EAA) for the use, education and enjoyment of chapter
members and others to whom it is provided. No claim is made for the
accuracy of the materials presented. Editorial content is the opinion of
the contributor and does not necessarily reflect the policies of Chapter
54 nor the EAA.
Submissions for publication are encouraged, and should be sent to:
EAA Chapter 54 Editor
3275 Manning Ave. N. Suite #7
Lake Elmo MN 55042.
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Permission for other EAA Chapters to use portions of this publication
is granted, as long as credit is acknowledged.
Chapter 54 gathers at 7:30pm, on the Second Monday of each month, at
Lake Elmo Airport, B Entrance.
President - FrBilly@EarthLink.net
Dan Parker 651-430-1532
Vice President - ParkerDc@quixnet.net
Wayne Asp 651-436-6868
Secretary - Wayne_Asp@HP.com
Bob Waldron 651-430-9178
Treasurer - rjWaldron@mmmpcc.org
Directors Class II
Gary Miller 651-774-0456
Publicity and Promotion
Leif Erickson 651-439-5040
Directors Class III
Art Edhlund 651-439-5912
Ed Peiffer 651-462-2517
Scott Hutchinson 651-777-1872
Past President Dick Wicklund 651-777-9142
Young Eagles Coordinator
Al Kupferschmidt 651-777-9257
Bill Schanks 651-645-2420
Dale Rupp 651-653-1054
Bill Schanks 651-645-2420
Bob Waldron 651-430-9178 firstname.lastname@example.org
WEB site www.eaa54.org
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