Chart help

Hey, I just got a quick question about charts. When it says Grad 3.3%, I’m assuming this is what the pitch of the aircraft should be. Right?

So, I just want to know how much 3.3% is. Like what should my pitch be?

I thought gradient is the approach angle. Usually it’s 3 degrees and 5.5 at London city

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This chart is a SID (departure) and it says the grad 3.3%

Since this is meant to be thought of in terms of ft per nm, that all depends on your ground speed. If you’re going 160 knots, your pitch isn’t the same as if you’re going 210 knots, because you cover that nm a lot faster at the latter speed.

It’s not a specific pitch they’re giving you, but a ft/nm rate of climb required for obstacle clearance.


Thanks. So, what do I do in IF?

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Here you go. Just took a screenshot on my phone real quick of the relevant info you are seeking.

Edit: Helps if I actually look at the contents of every post. There’s a chart above your last reply too.

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The formula is:

[Ground Speed / 60] * [ft/nm (from chart)] = FPM

So, a 3.3 gradient at 210 knots gs would be

(210/60) * (350) = 1227 FPM

You’ll note that 1227 is the number in the table under 210, so essentially it’s solving the equation for you for a lot of different ground speeds.


Ahh! Just needed that example. I understand that now. Thank you!

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For the altitude restrictions on your chart, most are “at or above” you would have to climb very slowly not to be able to meet them - as @Tim_B notes the fpm is very low and much lower than you would actually climb. 3% gradient for a climb is very shallow and not really what you would be doing.

GIXOX is the only waypoint with a restriction stopping you climbing further. You need to be at or below 7000 ft at that point. Basically that means you climb as normal but then stop at 7000ft at whatever point before GIXOX you get to that height. You them hold that altitude until you are past GIXOX and resume your climb.

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