general? Noise Abatement Procedure

[LevelMind 1]

I'm wondering how you are meant to know which NADP that should be used for departure. I know that it usually says on the charts, but at an airport such as EKCH it only says:

 

Noise Abatement Procedure

No turns allowed Before:

etc....

 

So should I assume NADP 2 should be used since that seems to be the normal one at which you accelerate and derate at the same time?

[DaveS 144]

Someone else can correct me, but I believe unless it states specific hours that a particular DP should be used, then the noise abatement procedure should be followed all the time. Usually the 'no turns allowed before' is to avoid overflying certain areas such as a residential area. 

[LevelMind 1]

Ok

 

But which NADP should be used? NADP 1 or NADP 2, since they're quite different i'd be good to know.

[Bsal 58]

It really depends on the airline and SOP, but most use NADP2 unless NADP1 is stated on the chart.

[LevelMind 1]

Ok thank you!

[LevelMind 1]

And also, while we're on this topic. I thought I'd ask if PROC A or PROC B (at which you'd climb with TO thrust up to 1500 feet before Climb thrust) is still used? Or if only the new NADP 1 or NADP 2 (at which you reduce to CLB thrust at 800 feet) is used?

[Bsal 58]

PROC A+B are now replaced with NADP's, for example at Easyjet they use NADP2 and 1000ftAGL for both thrust reduction and acceleration altitudes. Keep in mind the 800ftAGL for thrust reduction is just the minimum value allowed in NADP2 but it doesn't have to be that low.

[LevelMind 1]

Ah ok, thanks