PPRuNe Forums - View Single Post - PERFORMANCE EXAM (ATPL) Give us a clue?
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Old 23rd Jul 2004, 07:11
  #10 (permalink)  
Keith.Williams.
 
Join Date: Aug 2001
Location: Dorset
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One in Sixty,

What ALEX means is that if you look at your previous post you will find that you have got the nose up and nose down requirements confused.

For example your stated that:




"What happens with ANGLE of attack in a dive if you maintain MACH number from 35.000 feet to 25.000?

Here you note that if you maintain constant MACH it means your IAS will steadly INCREASE (go over the graph if you need to) and since it's INCREASING you actually need to DECREASE angle of attack. Which means, point your NOSE more upwards.
However Descent angle will not decrease, it will instead INCREASE. Draw it out and you'll see it clearly."




What you should have said was that to increase CAS to maintain constant Mach in a descent, you must push the nose down in order to decrease angle of attack and drag.


You also said:



"Here's a few more that I made up, well I didn't actually make them up, I changed the figures and text slightly.

What happens with AoA in a climb at constant MACH from 20.000 to 34.000?

If you maintain MACH, your IAS is decreasing. In order to maintain this, you'll need to lower the nose. Lowering nose now means decreased AoA. (Since the nose is already beyond relative horizontal)."



What you should have said was that to decrease CAS to maintain constant mach in a climb, you must pull the nose up to increase angle of attack and drag.

I suspect that you knew what you wanted to say but simply got it all a bit mixed up.
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