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daan_vb

Noise abatement procedures and the NGX

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Hi there,

 

I'm just wondering how I'd program the FMC takeoff cutback for a noise abatement procedure at an airport such as Liverpool EGGP or at Manchester EGCC that requests a 500fpm rate climb or more to comply.

 

From the AIP

 

Every jet aircraft using the airport shall, after take-off or 'go-around' maintain, after passing the relevant monitoring point, a rate of climb of

at least 500 ft per minute at power settings which will ensure progressively decreasing noise levels at points on the ground under the flight

path beyond the monitoring point.

 

Thanks

 

Dan

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The NG's pretty much always going to be above 500fpm in a takeoff or go-around - in GA it shoots for an 8% climb gradient, which usually ends up somewhere in the 1500-2000 fpm range depending on conditions. For takeoff, all this stuff is on the two takeoff pages - you can set your thrust reduction, acceleration, cutback, restore altitude etc there.

 

There's two kind of standard procedures for this called the NADP1 and NADP2 - in the NADP1, you reduce to climb thrust at 800AGL but don't push over and accelerate until 3000AGL. This gets you up high in a short amount of time over the ground - it's known as a "close" noise abatement procedure for that reason. In the NADP2 you reduce thrust and accelerate to flaps up speed at 800AGL and then accelerate to full normal speed at 3000 - this results in you being at a higher altitude further away from the airport and is known as a "far" noise abatement procedure. Which one you use depends on where the noise-sensitive area under the flight path is - if it's just off the end of the runway, you want NADP1, if it's further away you want NADP2.

 

There's a couple other noise abatement procedures like ICAO PROC1 and PROC2 but I believe these have now been superseded by the NADP ones. (It's pronounced "nad app" btw, not N-A-D-A-P - stands for "Noise Abatement Departure Procedure")

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737NG has Quota Count 0.25 category, so you don't need to use any noise abatement procedures in EGGP or EGCC.

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Very informative thanks guys!

 

So can I assume that, unless otherwise stated, the NGX doesn't need to abide by any noise abatement procedures under normal operation? Would a real world pilot remove the NADP settings in the FMC if there were none specified for aerodrome?

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Would a real world pilot remove the NADP settings in the FMC if there were none specified for aerodrome?

 

A company would specify that.

 

 

So can I assume that, unless otherwise stated, the NGX doesn't need to abide by any noise abatement procedures under normal operation?

 

Depends on how you define "unless otherwise stated". If there is NA procedure, NG does need to abide, unless otherwise stated (e.g. if there was a "jets under 100 tonnes MTOW need not use NADP" type statement).

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A company would specify that.

 

 

 

 

Depends on how you define "unless otherwise stated". If there is NA procedure, NG does need to abide, unless otherwise stated (e.g. if there was a "jets under 100 tonnes MTOW need not use NADP" type statement).

 

OK, I'm trying to apply a real world scenario into an FSX world haha. I don't want my virtual peeps to complain :-)

 

So at an airport like EGCC where it just says to climb at greater than 500fpm should I just leave the cutback procedures as set....

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Would a real world pilot remove the NADP settings in the FMC if there were none specified for aerodrome?

Most airlines probably use NADP-1 or -2 as their standard profile, so there's no reason to remove it. In the US, most pilots are doing NADP-2 and they don't even know that if they don't fly international. To them, it's just "the takeoff profile." In Asia, NADP-1 seems to be the standard, and SOPs are probably written to use that most of the time.

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In Europe, NADP 1 is the common one. Some airports will have it in their regulations, some airports will recommend it, at some it might just be a silent agreement.

 

Matt, you flew in Asia before current company?

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If you use Fs2Crew for NGX, you just choose between NADP 1 or 2, and Fs2Crew will configure the airplane right for you.

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Matt, you flew in Asia before current company?

I was Seoul based for a while on the -8 and -9.

But how do you program NADP 2 in your FMC?

That's a bit more difficult than NADP-1. You can SPD INT after you get to Flaps Up Maneuvering Speed and fly out at that until 3,000AGL and then close the window.

 

Or program the CLB page. On the CLB page, you could program the speed limit as 230/3000AGL and Target 250. When passing 10,000', you select ECON.

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That's a bit more difficult than NADP-1. You can SPD INT after you get to Flaps Up Maneuvering Speed and fly out at that until 3,000AGL and then close the window.

 

Or program the CLB page. On the CLB page, you could program the speed limit as 230/3000AGL and Target 250. When passing 10,000', you select ECON.

 

Thanks :D

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Great thread. TIL I learned NADP-2 is the common procedure in the U.S., whereas I used to think NADP-1 was default. Basically, I always used to select climb thrust at 1500 ft, and "nose over" at 3000 ft to accelerate to 250kts. I was curious about my homefield airport, KPHL, because contrary to the 3000ft flap retraction procedure I used, I had seen video evidence on youtube of airlines retracting flaps at a much lower height. Now I have my answer!

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I have one more question, in the U.S., is the climb thrust reduction altitude usually 800ft , or 1500, or 1000? Does company SOP dictate the altitude or the airport authority?

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As it was said above, in the US, most pilots are doing NADP-2. So thrust reduction in most airlines is 800ft for standart profile, what is stated in SOP.

Just special noise abatements like ICAO PROC A & B are issued by airport authority.

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