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APG calculations

Hi folks

Is here anybody familiar with APG landing calculations ?
On landing chart you will find calculations for each rwy in the following format

LIMIT/CODE/MA Grad/LD Dist./1.67 LD/V ref/V app/VFTO

LIMIT - weight limit
CODE - limitations code for.ex ST - structural
MA Grad - this one I can't understand - for.ex for EPWA there is 12.1 for RWY33 . I have no idea what kind of gradient it is . On APP chart for RWY33 there is no any requirements for MA climb gradient . Do you know what it is ?
LD DIST - this is unfactored landing distance
1.67 LD - 1.67 landing distance - this is required for commercial operations ?
Vref - reference speed
Vapp - approach speed
VFTO- ??

btw. if there is no any specific minima gradient on SID chart - what is the minimum gradient then ?

Thank you

Quote:

I hope you are not a professional pilot

Hmmm, where exactly did chr say he is one ? This kind of answer is pointless and condescending....

VFTO is the "final take off speed" - Vfto is the speed at which you climb (after reaching acceleration altitude) following an engine failure or single engine go around.
The definition of the FAA to be found here:
1-g Stall Speed as the Basis for Compliance With Part 25 of the Federal

is:

Final takeoff speed means the speed of the airplane that exists at the end of the takeoff path in the en route configuration with one engine inoperative.

it is determined:

Quote:

VFTO, in terms of calibrated airspeed, must be selected by the applicant to provide at least the gradient of climb required by §25.121(c), but may not be less than—
(1) 1.18 VSR (Reference stall speed); and
(2) A speed that provides the maneuvering capability specified in §25.143(h). (40° banked coordinated turn with asymmetric power at the WAT limit)

BTW: not every A/C manufacturer uses VFTO - most airplanes I flew use VENR for the same speed.

Quote:

1.67 LD - 1.67 landing distance - this is required for commercial operations ?

Sort of, yes. Its required for the planning of a commercial operated jet. Turboprops use 1,43.

Quote:

MA Grad - this one I can't understand - for.ex for EPWA there is 12.1 for RWY33 . I have no idea what kind of gradient it is . On APP chart for RWY33 there is no any requirements for MA climb gradient . Do you know what it is ?

Can´t follow you on this one, I have "apged" my airplane and did not find that gradient anywhere. (or overlooked it)

Have a look at FAA AC 120-91, Section 7, that explains a lot when it comes to SE performance.

Gradients found on Jeppesen SID charts do mean NOTHING at all for the engine out case. APG will either follow the SID or if a better performance can be had give you a DP you follow in case of.

Have a look also at flyapg.com, "resources", videos.

MA grad is the actual gradient the aircraft will achieve one engine out on the missed approach up to1500 feet above the runway in the conditions you have put in to the calculation.

What terrain margins does APG use in it's take off performance, I see sometimes huge restrictions for cat C airports where initial departure is VFR like Samedan or La Mole

...same margins as all the others: 35ft without turns scheduled - 50ft if a turn is required. They don't make money on limiting your payload, but on (the barest minimum of) regulatory compliance.

Now, there are airports where there is a margin between them and Flugprestanda - and this is probably where it gets interesting :\