Thought process: Best angle or Best Climb rate

[speedbirdhopeful1]

This is a good discussion, how does 1000/1000 NADP2 style affect the gradient compared to 1500/3000 for example? How would one calculate this as the tables really only refer to airspeed? It’s often used as a reason for using 1500/3000 somewhere with a turn (ignoring the climb gradient for now), but in reality you end up cleaning up before the turn anyway so why not do it at 1000?

[Intruder]

Also, where do you look for the best rate/best angle speeds for the various [post-]takeoff flap settings? Without some kind of chart, how do you determine them? I can't say that I've ever seen them for the 747...

If you're looking for the best climb angle, I'd use the minimum safe speed bug for the flap setting in use (like what is taught for an engine out after takeoff). The "best angle speed + 25 KIAS" guidance for the clean 747 probably would not work well for best rate...

[vilas]

World has moved on from 747 days. Airbus has published software like ADAS, OFP which gives all the information regarding after take off performance. Also there is PEP performance engineers programme which is used by the company before making SOP for the airfield. You don't decide every time sitting in the cockpit.

[Vessbot]

Originally Posted by Small cog

I disagree with your conclusion. The OP’s second paragraph in post #1 shouts that out loud to me.

Perhaps I’ve been fortunate to have had not just a good start with an in-depth mechanics of flight education and a short spell in a performance department.

When I sit in the sim (or aircraft/jumpseat) and listen to some of the longwinded departure briefs about what the PF will be doing (this that and the other) during the departure and that PNF will tune this, call that, select his/mine ... you know the sort? Any how, throw a simple failure or fault in the mix (in sim) and it all goes to pot, PF can’t fly for toffee, or follow the required profile ... I wonder, for starters, why not start by just flying the sodding aeroplane!

Yes, background knowledge is wonderful, but why not KISS, FtA, don’t try reinvent the wheel, and just operate the aircraft the way the Manufacturer and the Company want you too?

From the paragraph in which he asks how to weigh the merits of two different ways of climbing in the achievement of obstacle clearance, you disagree that he's looking to understand how climbing works? I guess we're getting different things out of it.

Besides, there's no need to play mind reader or detective when he explicitly said that my post addressed his concern, which I already pointed out.

You say to "fly the airplane," with which I agree wholeheartedly, but I struggle to see the connection between that advice and my post. (I also struggle to see how to "fly the airplane" in an airline/IFR environment without tuning in the necessary navaids, which you seem to suggest.)

You also suggest to fly the airplane the way the company and manufacturer want you to, and nothing I said contradicts that. You're creating false dichotomies between understanding flight and complying with the co/mfg profiles, and between understanding flight and maintaining the big picture upon which to fly effectively.

KISS is valuable to an extent, but I'll never agree that the relationships between drag and climb performance, and between the transient effects of flap retraction and climb performance, are too complicated for a pilot to understand. In fact the opposite is true, they're fundamental tenets of a necessary understanding of how flying works. At a most basic level. It's not reinventing the wheel, it's knowing that wheels are round.