Class A - Take-off Climb — Page 438, Lesson 537

We're moving into the second of the two noise-abatement departure procedures — NADP 2. This one is designed to alleviate noise distant from the aerodrome, as opposed to NADP 1 which handled noise close in. Let me walk you through exactly how it works. The core idea of NADP 2 is that you delay the power reduction and the flap/slat retraction until you're higher, so the aircraft is quieter when it's further away from the airport, over the communities that are more distant. Here's the sequence. The procedure involves initiation of flap/slat retraction on reaching the minimum prescribed altitude. So you don't start cleaning up the wing immediately — you wait until you've reached a specific minimum altitude. The flaps and slats are to be retracted on schedule whilst maintaining a positive rate of climb. That means you retract them in the normal, scheduled sequence, and throughout this you must keep a positive rate of climb — you must be climbing, never descending or even leveling off. Now, the power reduction. It's to be performed either with the initiation of the first flap/slat retraction, or when the zero flap/slat configuration is attained. So you have two options: you can cut power at the same moment you start the first flap or slat retraction, or you can wait until the flaps and slats are fully retracted — the zero flap/slat configuration — and then reduce power. Either way, at the prescribed altitude, you complete the transition to normal en route climb procedures. Now the critical numbers. The noise abatement procedure is not to be initiated at less than 800 ft above aerodrome elevation. So 800 feet is your floor — you cannot start this procedure any lower than that. The initial climbing speed to the noise abatement initiation point is V2 plus 20 to 40 km/h, which is 10 to 20 knots. So you climb out at V2, the take-off safety speed, plus a margin of 10 to 20 knots. On reaching an altitude equivalent to at least 800 ft above aerodrome elevation, you decrease the aircraft body angle — that's the angle of pitch — whilst maintaining a positive rate of climb. So you lower the nose, but you must still be climbing. You accelerate towards VZF — that's the zero-flap speed, the speed at which the aircraft can fly with the flaps fully retracted. And then you do one of the two options I mentioned: either reduce power with the initiation of the first flap/slat retraction, or reduce power after flap/slat retraction. Then you maintain a positive rate of climb, and accelerate to and maintain a climb speed of VZF plus 20 to 40 km/h — again, 10 to 20 knots — and you hold that speed up to 3000 ft above aerodrome elevation. So the target is VZF plus 10 to 20 knots, and you keep that until you reach 3000 feet. On reaching 3000 ft above aerodrome elevation, you transition to normal en route climb speed. That's the handoff — at 3000 feet, you're done with the noise-abatement profile and you fly a standard climb. So the key contrast with NADP 1: NADP 2 keeps the noise reduction further out, which is why you climb higher before you clean up and reduce power. The figure shows this — it's an example of a procedure alleviating noise distant from the aerodrome. Let me make sure you've got the speeds straight, because these are the numbers you'll be tested on. V2 plus 10 to 20 knots is your initial climb speed up to the initiation point. Then you accelerate to VZF plus 10 to 20 knots, and you hold that to 3000 feet. The altitude floor is 800 feet — never initiate below that. And throughout, positive rate of climb — that's non-negotiable at every stage. That's NADP 2. Now, the book has practice questions on this — let's try them one at a time.