AoA keep it going!
Kirk,
Could you summarize for me _how_ you used the AOA indicator in those
aircraft, which aircraft and under what conditions ?
I am curious to the actual use(s).
Thanks
Todd Smith
3S
Sure. I used AOA in T-38s (a little - not much flight time in those)
and in F-4s (about 2000 hours in those). In my current job, I fly a
variety of F-15 simulators (the real thing, not PC games) and use AOA
all the time. Have also a few flight in F-16s and a lot of time in
F-16 simulators, which use AOA in the approach and landing
configuration.
In a nutshell, AOA is used anytime optimum performance is required
from the wing - be it turning, flying an approach, flying for max
range, recovering from a dive, etc. Since fighters can vary weight a
lot due to fuel burn and store (weapons) configuration, it's
impractical to try to use airspeed other than as a general guide to
your energy state - your airspeed tells you how much instantaneous
energy you have to maneuver, then you fly at the AOA that matches the
type of turn you want - less AOA is conserves energy, more AOA turns
faster, etc. If you are flying for max range or max endurance, again
there is a recommended AOA to fly at - it will stay the same while
the actual airspeed changes based on gross weight, configuration, and
altitude. Finally, in the pattern, you figure out the approximate
airspeed and AOA based on fuel and stores remaining, then crosscheck
the two - if they agree, it's easier to fly AOA on most jets (F-4
especially, F-15 less so).
Now, compared to gliders, these are all extremely low aspect ratio,
and that will exaggerate AOA effects. But the aerodynamic priciples
are the same.
Finally, someone questioned about whether it's better to thermal
efficiently or in the best part of the themal. The answer, IMHO, is
that you should strive to do both. Right now we have wonderful
instruments to help us find the best lift. But we still use a crude
instrument to fly efficiently. Well, actually, most people probably
thermal more by feel and attitude than by staring at the airspeed
indicator.
End of war story.
Cheers,
Kirk
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