A320 - when does ac activate app mode ?
Joined: Mar 2006
Posts: 2,633
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From: USA
Systems Manual section 22-30 (Managed Speed/Mach Target)
Unless I'm misreading that completely, if APP Phase is not activated, and you push for managed speed, the AT should limit the speed to Vfe if flaps are extended.
I'm new on type. Am I missing something?
If the managed speed/Mach target is set above VMAX (VFE, VMO, MMO), the FMGS automatically limits the speed to VMAX
I'm new on type. Am I missing something?
Only half a speed-brake
Joined: Apr 2003
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From: Commuting not home
CA: Almost correct I think. The FMGS will limit the speed to Vmax, but the AT will agressively chase the cca 30kt faster target and will eventually overshoot. Never had the chance to test the feature properly myself, on the several occurences so far as a crew we were fast enough with the corrective actions (touch wood).
In a similar fashion should a flap/slat overspeed be imminent after takeoff / GA, selecting flaps/slats lever up one step will remove the barber pole from the speedtape at once, however the overspeed may still occur while devices are in transit. FDM/FOQA will have a record of the exceedance so PIC better make sure the techlog entry is there as it should.
In a similar fashion should a flap/slat overspeed be imminent after takeoff / GA, selecting flaps/slats lever up one step will remove the barber pole from the speedtape at once, however the overspeed may still occur while devices are in transit. FDM/FOQA will have a record of the exceedance so PIC better make sure the techlog entry is there as it should.
Last edited by FlightDetent; 9th December 2015 at 19:45. Reason: Improved clarity, hopefully. :)
Joined: Jan 2000
Posts: 2,372
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From: Asia
I managed the speed on final one day without having the approach phase activated, the engines instantly powered up and we started accelerating. The Master Warning went off as flap limiting was exceeded before the head of the training department who was in the left hand seat pulled the speed knob. I was rewarded with a large number of extra sectors added to my program.
Also worth noting that if you are on an arrival and a speed constraint has activated below 10 000', say 220kts, if you go into heading mode the speed will increase to the default of 250/10 000. Worth keeping a look out for.
Also worth noting that if you are on an arrival and a speed constraint has activated below 10 000', say 220kts, if you go into heading mode the speed will increase to the default of 250/10 000. Worth keeping a look out for.
Joined: Nov 1999
Aviation Qualifications: ATPL
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From: UK
That doesn't work if ATC have given you a speed(s) for sequencing. Happens on almost every approach to my base.
In fact, as soon as London TMA starts giving us speeds, we go selected speed and then activate the approach.
In fact, as soon as London TMA starts giving us speeds, we go selected speed and then activate the approach.
