PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Tech Log (https://www.pprune.org/tech-log-15/)
-   -   Turn Radius Formula & Ascending/Descending Turns (https://www.pprune.org/tech-log/429509-turn-radius-formula-ascending-descending-turns.html)

Badmachine 3rd Oct 2010 23:26

Turn Radius Formula & Ascending/Descending Turns
 
When calculating the turn radius for an ascending or descending turn, does the gravitional constant value need to be adjusted accordingly?

Could the standard turn radius formula apply to ascending or descending turns and generate correct results?

BOAC 4th Oct 2010 07:28

In practical terms, no. The other variations in performance, human, computer and nature far exceed the small variations due to what are normally small descent/
climb angles.

Why in particular the question? Are we theoretical or practical?

CabinMaster 4th Oct 2010 09:43

You want to calculate turn radius?
That is a pure function of turn acceleration and level flight speed (true). It is the acceleration you actually put in the turn.
It is no problem to separate vertical from lateral motion.

compressor stall 4th Oct 2010 10:20

Why stop there? What about the relativity issues?

Piltdown Man 4th Oct 2010 10:53

Probably yes, but a close enough formula is TAS (Metres/Second) Squared/(Tangent of Angle of Bank * g). For g I'd use 1.

PM

CabinMaster 4th Oct 2010 11:26

g still is approximately 9.81 m/sē.

BOAC 4th Oct 2010 12:49

Maybe gravity in Piltdown is much less? Is it on the moon?

hetfield 4th Oct 2010 12:53


Maybe gravity in Piltdown is much less? Is it on the moon?
Must be somewhere else, on the moon it's 1.63 m/sē.

BOAC 4th Oct 2010 13:14

Now - this is a matter of some gravity. A weighty problem indeed.

CabinMaster 4th Oct 2010 15:56

Or he uses a different unit.
The answer is always "42".
Just the unit changes.

Rivet gun 4th Oct 2010 16:35

A very good point. I suspect he is using the TGM unit system, which is best for people with 12 fingers :)

TGM - a coherent dozenal metrology

Pugilistic Animus 6th Oct 2010 00:57

no...the circumferential velocity vector, and the vertical velocity vector are kinematically independent; they are mutually exclusive axes:)

shafqatgreat 16th Jan 2017 05:18

How to calculate a turn radius for descending turns.
 
How to calculate a turn radius while aircraft is continuously descending(with some dive angle) and turning with specific bank angle.

RAT 5 17th Jan 2017 10:51

Don't forget to factor in the rotation of the earth as you descend, and the change in pressure. :rolleyes:

Broomstick Flier 17th Jan 2017 12:53

I was about to mention Coriolis effect, but small cog beat me on that...


All times are GMT. The time now is 17:52.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.