Would someone care to explain the last part for me? How does the gradient %times groundspeed translate into FPM?

Thanks!

Sure!

For example, if you have a rise of 500 feet per mile, and the run is one nautical mile, you divide rise over run, move the decimal over two places (x 100) and then you have a gradient.

A good rule of thumb is to take the gradient times your groundspeed to have and estimated climb rate in feet per minute. Or, you can look at the rate of climb table in the front of the Jeppesen (tables and codes) book.

I'm dusting off my trigonometry here, so mathematically the vertical distance that you are climbing equals the sine of 8.23 times the opposite over the hypotenuse: take that distance and divide it by 360 to arrive at feet per minute.

that better be a chick's a$$ :D

How do you calculate FT/NM?

Thanks

groundspeed / 60 = Z (nm per minute)

Climb rate / Z = Ft per NM
.................................................. ..

120kts / 60 = 2 nm per minute

2000 / 2 = 1000 ft per nm

Get ultranav.. Does it all for you

Thanks RI830

If Gradient = fpm/feet_in_one_minute

then fpm = feet_in_one_minute * gradient

ex: 450 fpm, 150GS

find how many feet traveled over the ground in one minute: 150kts/60' = 2.5 NM * 6000 = 15000ft traveled over the ground in one minute.

then

Gradient = 450ft/min/15000 = 0.03 * 100 = 3% gradient

so 3(gradient) * 150(GS) = 450 ft/min
or 0.03(before the multiplication) * 15000(feet traveled in one minute) = 450ft/min

whichever you like :)

I hope the guy from 11 years ago comes back and reads your reply.

Closer to a 4.7% Angle but the fpm is correct