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Old 21st Feb 2017, 15:13
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First.officer
 
Join Date: Apr 2004
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for what You asking for, Napd1 1500/3000 are height and you don't have to add the airfield elevation
ICAO Doc. 8168 quotes;

2.5 At no more than an altitude equivalent to 900 m (3 000 ft) above aerodrome elevation, while maintaining a
positive rate of climb, accelerate and retract flaps/slats on schedule.
Now, I've seen that if you included the airport elevation in the MCDU (for NADP1), the aircraft will indeed prompt (FMA) 'LVR CLB' at the appropriate point (SOP for us is 1,500ft above aerodrome elevation), with acceleration (FMA 'CLB' I think!) at 3,000ft above aerodrome elevation. The figures achieved in seeing the relevant FMA's (in relation to NADP1) are with the aerodrome elevation included, i.e. QNH set.

I appreciate that the doc. 8168 criteria are achieved after 800ft anyway, and airline SOP's are structured as the operator may desire, but it does mean that if you reduced thrust at 800ft (as entered on the MCDU, i.e. '800'), then the aircraft will ask for 'LVR CLB' at 800ft, but this would be with the QNH in all likelihood set on the altimeter sub-scale yes? so therefore would not be an NADP1 departure, as it needs to be at, or above 800ft aerodrome elevation?.

Now I know that any and most likely all operators don't use the '800ft' as an thrust reduction altitude (usually in all I've known, its >=1,000ft, or higher), but this hopefully means I've got the details correct here? I have observed this quite a few times now when carrying out NADP1 departures in the A320 series, so this is what it does....but I await a more informed correction/response if I'm wrong?

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