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Sal007
22nd Apr 2014, 09:56
Calculate the rate of climb for an aircraft operating at 3000ft OAT 0C.
Conditions-
Flap Up
Landing Gear Retracted
Full Throttle

Can Someone please give me the Formula for this calculation ?

Saratogapp
22nd Apr 2014, 10:11
Mmm .... A tricky one, really. Are you in a C150 or mirage?

foxmoth
22nd Apr 2014, 10:26
Normally done from tables rather than formula, example here:-
http://selair.selkirk.bc.ca/training/Program_Manual/documents/program-manual-appendix14.pdf

Pirke
22nd Apr 2014, 11:07
Can you assume best climb speed? Or is a certain speed given?

foxmoth
22nd Apr 2014, 14:44
Don't schools teach people to read the POH these days??
I certainly teach my students where to look - All this info is in there!:rolleyes:

Mach Jump
22nd Apr 2014, 15:26
Foxmoth is right.

Rate of climb for given conditions is not calculated by a formula, but by reference to charts or tables like the ones he has posted. These are derived from flight test results adjusted for varying conditions, and can be found in your Flight Manual or Pilot's Operating Handbook. (POH)

Can I ask, are you studying for a PPL or do you have one already?

If you are studying for the Performance and Planning exam, then graphs, charts and tables will be provided for you to work out things like rate of climb.


MJ:ok:

rapidshot
23rd Apr 2014, 02:57
Sal, for climbing calculations u need to know,

excess power
prop efficiency,
aerodynamic drag of the airplane,
and many other..

it can not be calculated by a simple formula,

abgd
23rd Apr 2014, 04:54
Or is the original poster's point that the question is badly worded, as it should not be something you determine rather than calculate?

One exception being if you have to interpolate it.

Mark 1
23rd Apr 2014, 05:30
I'm guessing that our OP isn't very far along their PPL and has been looking at some sample questions and wasn't sure how to approach them.

The data supplied in the POH or flight manual will likely have climb rate tabulated for weight, altitude and delta-T(ISA).

At 3000' the standard temperature will be 9°C so the delta(T) will be -9°. For practical purposes you could use -10° as there will probably be tabulated or plotted for 10 degree steps. There may be additional tables or graphs for different configurations of flaps and undercarriage, so make sure you are looking at data relevant to the clean configuration.

The point about interpolation is valid, as strictly you will likely only have figures for ISA and ISA-10° and the value for ISA-9° will be estimated by linear interpolation.
E.g. if you have 1000' ft/min at ISA and 1100 ft/min at ISA-10° then interpolation would estimate 1090 ft/min at ISA-9°. (colder air is more dense so increases the power available and hence the climb rate).

Sal007
30th Mar 2015, 11:21
Thanks Guys , i go the answer .

foxmoth
30th Mar 2015, 14:54
Nearly a year from asking the question to reading the replies by the look of it - what have you been doing?

Sal007
30th Mar 2015, 15:18
I've been away for Training Purposes . Good Days ahead