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Old 19th Jan 2006, 20:06
  #10 (permalink)  
enicalyth
 
Join Date: Jul 2004
Location: Sydney NSW
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speed bumps?

G'day wondering!
What do you want the speed profile to look like? Rough Q & A.
35ft above the deck and CAS 175, what will it be at 1500ft above and cleaned up? Still about 175? Suppose you then accelerate in level flight to CAS 250 and then climb? You reach 10000ft and CAS is still 250 but Mach has risen to 0.45 and TAS to 290. Yes? Suppose you then accelerate in level flight to say CAS 275? Here you lose me a bit. I think you'd still climb at a fixed CAS say 275 but Mach No and TAS would still be increasing. Yes or no?[You wouldn't alter speed again until say M0.82 but that's a long way above you yet].
Flight path angle is directly related to (Thrust-Drag)/Weight. Horizontal and vertical speeds are directly related through flight path angle. CAS, TAS and Mach No are related by formulae. The options to plot profile in terms of CAS, TAS etc against time, distance, height, altitude, Flight Level are your choice but which part looks strange? There will be coggles when you accelerate and change from one regime to another will there not? Won't they be mutually explainable?
OS! Bird strikes do take place above 10000ft. On a Boeing data recorder they are dead ahead and show up as momentary speed reductions. On an Airbus they are from dead aft and show up as momentary speed increases. This explains otherwise unexplainable speed profile variations.
I'll get my coat
The "E"
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