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Thread: Airbus ALT*
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Old 21st May 2021, 08:43
  #30 (permalink)  
Fursty Ferret
 
Join Date: Sep 2011
Location: FL390
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No! During ALT* leave it alone it's too late.
Going to respectfully disagree here.

Consider the situation where you climb into an increasing headwind at high level and experience a transient increase in airspeed, leading to a high rate of climb. If ALT* engages at this point you could be several thousand feet below your target altitude with the speed about to wash off. VS 0 is a perfectly reasonable mode to consider at this point to manage the energy situation. You can re-engage climb or select a sensible VS once the energy of the aircraft is doing what you want. Pulling for VS will just put you back into ALT*.

If you realise that this is going to happen a better way to manage the situation is to select the airspeed or Mach at something close to VMO or MMO, so that if the headwind washes off you can just go back to your original speed instead of experimenting with the low speed protections.
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