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## Rate of Climb question

• bundybird
• Topic Author

### bundybird created the topic: Rate of Climb question

Hi

Help me with this cyberexam question please. I cant find anything like it in the book.

The rate of climb required to allow an aircraft to achieve a 6% climb gradient at 5000ft density height if the climb was made at 80 IAS in a 20knot headwind would be closest to
350 ft/min
400 ft/min
200 ft/min
300 ft/min

Thanks
Anne

• Posts: 2046

### bobtait replied the topic: Re: Rate of Climb question

Gidday Anne

On page 4.4 of the performance book you will find a section called 'Calculating the climb gradient'. There is a formula you can use to find the rate of climb required to achieve a given climb gradient.

Rate of Climb = Requred gradient x ground speed.

To find the ground speed you must first find the TAS. 80kt IAS at Density Height 5000ft gives a TAS of 86kt. In a 20kt headwind, that gives a ground speed of 66kt.
The required gradient is 6% so:

Rate of climb = 6 x 66 = 396 ft/min. You would choose the second answer of 400 ft/min.