PPRuNe Forums - View Single Post - VLS speed increase in turn ?
View Single Post
Old 23rd July 2011 | 17:39
  #16 (permalink)  
Mad (Flt) Scientist
20 Anniversary
 
Joined: Sep 2002
Posts: 2,188
Likes: 6
From: La Belle Province
Originally Posted by Microburst2002
Mad scientist

It wouldn't make any sense that VLS was load factor sensitive. It would be as weird as if V2 was.

When you fly at VLS you know that you have a margin (arbitrarily determined) that should allow you "reasonable" manoeuverability without stalling. In the airbus PFDs, if you fly at VLS and pull up and bank steeply you will see Valpha prot and alpha max increasing towards a steady VLS, thereby indicating the effect of the load factor.

Otherwise VLS would increase above actual airspeed and that would be annoying because VLS is supposed to be a safe enough target airspeed.
I agree that a display that does that isn't very useful as a target speed while manoeuvring. BUT

I know for an absolute fact that the "green line" displayed on CRJs for FAA aircraft, which is intended to show a nominal Vref type speed, and thus is very like this VLS speed, does precisely what the OP suggests VLS does on the display, and for the reasons i gave in the second post.

As I said, we considered a g-compensated display, such that it did not move during manoeuvring, but this was not required of us by the FAA, so what ended up implemented was the simple version. When the display was considered as an option for non-FAA aircraft, other authorities required that it be g compensated, but there was no requirement for the indication either, so it simply was omitted.
Mad (Flt) Scientist is offline  
Reply