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Old September 11th 03, 02:14 AM
Mike Marron
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"Gord Beaman" ) wrote:

Ok, I see now why you said "see the F-8 Crusader".
John emailed me this URL which partially explains it's wing
shenanigans.
http://pacificcoastairmuseum.org/200...Crusader/j.asp


Quote from URL:
"No, the wing isn't about to fall off. It was designed to do
this so that the fast moving Crusader could slow down enough to
land on the carriers. This also kept the nose of the airplane
down during landing so the pilot could see."
Unquote


I still don't see the purpose here unless it's _only_ advantage
is the second sentence in the quote there. Why would an increase
in AOA 'help the a/c slow down for a carrier landing'?...of
course it would 'slow down' BUT it'd now be way high on the
glidepath TOO. Just as it would be if you hauled back on the
stick...


Haven't you heard the old axiom, "pitch for airspeed, power
for altitude?" (See below).

the _only_ advantage that I can see for this capability
of the F-8 is to lower the nose for better visibility from the
cockpit. Mind you, that must have been a large advantage imo.
'cause it seems to me that that'd be a big engineering project.


The F-8 won the Collier Trophy for the year's (mid 1950's) greatest
achievement in aviation. Besides just increasing the visibility, the
variable incidence wing also enabled the sleek and very fast
fighter to maintain the slower speeds required for carrier ops.

Please guys, tell me where I'm wrong here...


A/c is flying smoothly down a three degree glide-path,
the wing's AoA is 5 degrees. AoI is zero. (guesses of course)


Pilot pops the 'AoI switch', AoI becomes 5 degrees, AoA becomes
10 degrees, a/c tries to climb, pilot prevents that by pushing
stick forward, AoA now returns to 5 degrees and a/c ~returns to
glidepath. (Fuselage is now at a steeper angle than it was).


You're not just along for the ride so before you start flipping
switches and reconfiguring the A/C for the approach and
landing you anticipate changes in airspeed, drag, power and
stick pressure etc. so as to stay on the glideslope w/o exceeding
your critical angle of attack.

In other words, in your scenario above when the pilot increases
the wing angle of incidence (7-deg's), he simultaneously adjusts
his pitch and throttle settings as needed so as to remain stabilized
on the glideslope. He just doesn't gaily "pop the AoI switch" and
then react to what the airplane does...he thinks ahead and anticipates
what the airplane will do and plans accordingly (e.g: "fly the
plane" and pitch for airspeed power for altitude" etc.).

Maybe an F-8 driver can jump in here and explain better than I can.
I can only tell you that when landing my variable incidence A/C,
I can adjust the wing's angle of incidence (instantly if I wish)
simply by pushing the control bar full forward (unlike a conventional
airplane, the stick is situated horizontally so it's called a "bar"),
or pulling the bar full aft into my gut. And I can coordinate the wing
angle of incidence/attack and throttle depending on the type
of landing (e.g: short field, soft-field, crosswind, solo or 2-up, wet
or dry wing, etc.) fully stabilized on the glideslope w/o porpoising
up and down and/or making any radical changes in airspeed...


-Mike ( could land 3 times [crowhop] on an aircraft carrier Marron