NADP 2 (Noise Abatement DEP Procedure) for B747-400

[FlywithPark]

Hello Guys. I'm quite newbie @ B747.

I got a question yesterday about NADP 2 procedure for B747.
What i understood about NADP2 is we have to maintain V2+10~20 until 800' HAA. then while reducing flaps we need to accelerate to Vzf(what i understood is this is "Flaps up" speed. right?) with PWR recuction.
and at or above 3000 HAA we can accelerate to certain spd(250 below 10000' or MAX ANGLE SPD).

so we need to maintain Flap up SPD until 3000 HAA by SPD intervention then after 3000 HAA we can cancel SPD intervention to accelerate. is this right?

i've never seen who follow this procedure so far. as normally we set "10/1000" and "Flaps 5" at TAKEOFF PAGE, after 1000' we just accelerate to 250 or MAX ANGLE SPD with Flap reduction.

How about your opinion?

[Oakape]

However MarkerInbound, that is NADP 1.

[MarkerInbound]

Yeah, I deleted that post. That's why I always found it easier to just say we're going to do a close in or distant noise abatement procedure.

To the OP-

Your company can set set whatever procedure they wish as long as it keeps your CAA happy. That being said, normally a NADP 2 (distant) has you start to accelerate and clean up the flaps leaving 800 or 1000 feet. Boeing says to accelerate straight to your maximum rate of climb speed.

[D'pirate]

For 744 in my company NADP 2 1000' AAL accelerate, retract flaps on schedule, at Flaps 5 default CLB (Climb thrust), climb at Vref 30 +100 or 250Kts (whichever is higher) until 10000 then econ climb. NADP 1, at 1500' set CLB, at 3000' AAL accelerate and retract flaps on schedule then as per NADP 2.

[Too Few Stripes]

Straight from ICAO Doc 8168
NADP 2 -
3.1 This procedure involves initiation of flap/slat retraction on reaching the minimum prescribed altitude. The
flaps/slats are to be retracted on schedule while maintaining a positive rate of climb. The power reduction is to be
performed with the initiation of the first flap/slat retraction or when the zero flap/slat configuration is attained. At the
prescribed altitude, complete the transition to normal en-route climb procedures.
3.2 The noise abatement procedure is not to be initiated at less than 240 m (800 ft) above aerodrome elevation.
3.3 The initial climbing speed to the noise abatement initiation point is V2 + 20 to 40 km/h (10 to 20 kt).
3.4 On reaching an altitude equivalent to at least 240 m (800 ft) above aerodrome elevation, decrease aircraft
body angle/angle of pitch while maintaining a positive rate of climb, accelerate towards VZF and either:
a) reduce power with the initiation of the first flap/slat retraction; or
b) reduce power after flap/slat retraction.
3.5 Maintain a positive rate of climb, and accelerate to and maintain a climb speed of VZF + 20 to 40 km/h (10 to
20 kt) to 900 m (3 000 ft) above aerodrome elevation.
3.6 On reaching 900 m (3 000 ft) above aerodrome elevation, transition to normal en-route climb speed.
3.7 An aeroplane should not be diverted from its assigned route unless:
a) in the case of a departing aeroplane it has attained the altitude or height which represents the upper limit for
noise abatement procedures; or
b) it is necessary for the safety of the aeroplane (e.g. for avoidance of severe weather or to resolve a traffic
conflict).

[Intruder]

The 3000' acceleration is obviated because the V2+20 KIAS IS the normal climb speed below 10,000' (unless the 250 KIAS limit is waived).

[FlywithPark]

thank you for your replies.
however, what i wonder was whether we need to maintain flap up spd until 3000' or not.(for NADP2)
there is almost 20kts difference between flap up spd with 250kts or max algle spd we need to maintain until 10000'.
i remember i did this manner during my days of airbus a320.(until 3000' to green dot spd and after 3000' to managed spd)
am i confusing something?:rolleyes:

[Intruder]

Yes, you're confusing procedures for 2 different airplanes (and maybe 2 different airlines).

Why would you use max angle speed in normal operations instead of max climb rate speed?

In the 744, Vref+100 is normal climb speed below 10,000'; then transition to max climb rate (or ECON CLIMB) speed.

[Too Few Stripes]

The text clearly states that flap up speed +10-20kts should be maintained until passing 3000', then transition to normal climb speed. This is one of the most consistently poorly performed/understood procedures I see on the line and don't understand why, unless of course I'm missing something here?

[Intruder]

In context, the OP asked specifically about the 744. In that airplane, Vref+100 = Vzf+20 = minimum climb speed = normal climb speed below 10,000'. So, there is NO need to worry about acceleration at 3000'. Only on a VERY light ferry flight will you see Vref+20 <250KIAS, and then only by a few knots; you'll also be >3000' in a heartbeat...