quetion IFR rating

[argpilot]

can anyone tell how to solve it?

A particular instrument departure procedure requires a minimum climb rate of 210 feet per NM to 8,000 feet. If you climb with a groundspeed of 140 knots, what is the rate of climb required in feet per minute?

thanks

 

[Say Again Over]

Particular climb gradients on SID's usually has a nice little chart that you use to determine that question, given a certain climb gradient like 4%, opposite your ground speed you will read the required ROC.

 

[Say Again Over]

I'm not a rocket scientist but I would guess working with your figures it would be something close to this:

8000 Ft/210 Ft = 38.1 Miles (min climb grad)

38.1 miles/140 KTS = 16.3 Minutes

8000 Ft/16.3 = 491 FPM ROC

The gradient itself is: 210 Ft/mile = 2.1 Degree climb angle.

 

[argpilot]

acuatually is was looking for this formula,

feet per NM/ 60 * Speed

 

[midlifeflyer]

acuatually is was looking for this formula,

feet per NM/ 60 * Speed

Yup, that's it. But keep in mind that the "speed" in the calculation is groundspeed. And it's usually stated as

Feet per NM X GS/60

to make it consistent with other formulas (and for a bit of logical consistency) where we take speed and divide or multiply by 60.

It's also an easy manual E6B calculation: Put the mark under the airspeed and read required rate of climb over the gradient

The chart books also have a table for it, but using the formula is pretty simple.