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Old 24th May 2008, 16:07
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BraceBrace
 
Join Date: Feb 2003
Location: Blue sky
Posts: 277
Received 7 Likes on 6 Posts
No seasoned pro, but one thing I see happen a lot is overcorrecting, both in pitch and roll. You need to spot possible deviations in time, but these deviations are usually a result of either bad pitch, or bad bank. Especially in the sim where you (at least we do) usually have a fairly steady wind.

Pitch:
In real life and even with light gusty conditions you have some stick work to do to keep the airplane wings level, in the sim this is hardly ever the case. Flying raw data, I quite frequently totally loosen the grip on the stick because this way I'm sure I'm flying in a stabilized way with small corrections. Trim is very important, but the last step. Don't change your attitude with the trim, use the stick, then trim.

There's a rule of thumb: TAS/60 * 100 is the change in descent/climb rate for 1° attitude change. At ie 150kts this means every 1° in pitch is a change of 250fpm less or more. That's more than enough once you are stabilized. 3° gives you 750fpm less or more, which is close to the ground the ABSOLUTE maximum correction. 3° pitch change on the glide gives you a descent range from level flight to 1500fpm descent. This means at pretty much all times for a 30°flaps ILS, pitch stays between 0 and 5° initially if you're not on the glide, closer to the ground that becomes 1°-4° for MAX corrections. But usually 2-3° will do it for an ILS.

Roll:
30° for the intercepts, once established 10° bank max far out, reducing to 5° max bank closing in on the runway. Use every possible aid, ie a track line, or track diamond. Also check your thrust. Too many people can't get the wings to stay level because they don't notice they have a slight assymetric thrust. Check your N1's. Correct gently, and keep use your hand to block the throttles in their relative position from eachother (I don't know if I'm making any sense to you now...)

Thrust:
Bleed the speed off and approaching the Vref + 10 get the thrust in, initially about 45%, gradually increasing to 55%.

So in general, don't overcorrect. Too many people lose one item out of sight (usually attitude or bank) and trying to come back they react with an impulse, overcorrect and make the correction too big leading to a certain unstability.

Good luck and enjoy the raw data! It's pure fun...
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