Formula for Radius of Turn
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The only time a formula is helpful is in a descent. We made it a game to reduce smoothly to idle power at altitude and calculate our winds and weight to not power up until 1,000 ft. Speed brakes were not allowed, just slight AS changes. My first airline in 737's we didn't even have a GS readout and we still could do it. You can't get much smoother than that.
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This thread has had lots of accurate formulas and calculations submitted. Here is another one. This time it is an excel calculator for radius of turn. Not too sure if it can serve any one's practical needs. If you find any mistake, let me know and I will fix it. 
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The following two rule of thumbs from this thread, I found, are easy to use.
Download file through your browser
The following two rule of thumbs from this thread, I found, are easy to use.
Originally Posted by Artisan
For a rate one turn, use a Bank Angle of =(TAS/10)+7 (Degrees)
Originally Posted by Jetpipe.
The 1%*GS*½ is the best rule of thumb ever for RATE 1 turns up to 250kts so thats what I m keeping from this thread.
Last edited by aditya104; 9th Feb 2017 at 11:04. Reason: File reuploaded
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We made it a game to reduce smoothly to idle power at altitude and calculate our winds and weight to not power up until 1,000 ft
Even more fun (freighter ops) was to climb to whatever maximum height one calculated .. nose over (without any cruise) for the descent .. and then as you have indicated ...
Used to be the highlight on Sunday morning paper runs HBA-LST on the Electra ..
Even more fun (freighter ops) was to climb to whatever maximum height one calculated .. nose over (without any cruise) for the descent .. and then as you have indicated ...
Used to be the highlight on Sunday morning paper runs HBA-LST on the Electra ..
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90% of the time we could do the idle descent to 1,000ft but different winds would sometimes make you lose the game if they changed a lot through the lower altitudes. We always knew the winds would diminish but didn't know how much. We had a lot of one hr flights to the Bay Area so needed something to challenge us and not get bored.
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but different winds would sometimes make you lose the game if they changed a lot through the lower altitudes
.. but we got very good at recalculating mental profiles every mile or so and running ± 5-10 knots on the descent to adjust for wind ... rarely did anyone lose the plot entirely. Mind you, ATC sometimes would make things harder than necessary ..
And, invariably, this was all done raw data and no FMS.
.. but we got very good at recalculating mental profiles every mile or so and running ± 5-10 knots on the descent to adjust for wind ... rarely did anyone lose the plot entirely. Mind you, ATC sometimes would make things harder than necessary ..
And, invariably, this was all done raw data and no FMS.
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We had B737's with no GS readout so used DME and watch to figure GS. We were happy if the autopilot worked. Guess that is why I don't understand automation dependency by some posters. We never needed it and the aircraft flying today are no harder than our old planes to fly. Only the new pilots seem to sometimes have a problem if automation fails.
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A simple explanation :
Circumference of a circle = 2 x pi x R
If the TAS = 120 kts/ h, then aircraft is travelling at 2 nm per min.
A rate 1 turn~ 360 degrees in 2 min.
So 2 x pi x R= 4 nm
Therefore R= 4/ (2 x pi)= 2/pi=2/3.14=0.63 nm
which is roughly TAS/200
Circumference of a circle = 2 x pi x R
If the TAS = 120 kts/ h, then aircraft is travelling at 2 nm per min.
A rate 1 turn~ 360 degrees in 2 min.
So 2 x pi x R= 4 nm
Therefore R= 4/ (2 x pi)= 2/pi=2/3.14=0.63 nm
which is roughly TAS/200
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Aditya, Are you still working on this?
It would help if you had input for KIAS, altitude, and tailwind components. This would make it more flexible using for the KTAS calculation.
Turn radius parameters always begin with a fix at the beginning of the turn, you can then add the wind component with angle. This will be used to determine the max bank angle, not simply bank angle. Winds have significant effect on bank angle.
FAA/ICAO calculations use a 50kt tailwind that follows the ac through the turn, so it simply adds 50 kts to the entire path. Other proprietary software uses the wind component, usually to advantage in the max bank angle determination.
It would help if you had input for KIAS, altitude, and tailwind components. This would make it more flexible using for the KTAS calculation.
Turn radius parameters always begin with a fix at the beginning of the turn, you can then add the wind component with angle. This will be used to determine the max bank angle, not simply bank angle. Winds have significant effect on bank angle.
FAA/ICAO calculations use a 50kt tailwind that follows the ac through the turn, so it simply adds 50 kts to the entire path. Other proprietary software uses the wind component, usually to advantage in the max bank angle determination.
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With nil winds the aircraft would fly a circle for which a radius can be calculated.
Track with nil winds
With winds in the equation, the aircraft would fly a helix spiral which does not have a radius. See below image which shows aircraft track with northerly wind.
Track with nil winds
With winds in the equation, the aircraft would fly a helix spiral which does not have a radius. See below image which shows aircraft track with northerly wind.
