Quick Question

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Gyronaut
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Quick Question

Postby Gyronaut » Mon Oct 29, 2007 9:15 pm

Please resolve a debate for us: If an aircraft travelling at 80mph goes into a 30degree co-ordinated turn, will the radius of the turn be greater or less than the same aircraft, under the same conditions at 160mph. ?

This of course applies to fixed wings and gyro's alike.

We've contemplated lift vectors and inertia and have no conclusive answer.... please help?
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DieselFan
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Postby DieselFan » Mon Oct 29, 2007 10:51 pm

Is this a trick question?

If I understand your q properly executing a 30 degree bank Radius would be less, think about it you'd cover much more distance at 160 vs 80mph even if say the time taken to complete a 360 was the same the diameter or radius would be double if not that the circumference should be :wink: .

Higher speed and same bank angle = bigger hole in the sky

What have I missed? Turn without bank? ie rudder...
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Rudix
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Re: Quick Question

Postby Rudix » Tue Oct 30, 2007 5:38 am

JetRanger wrote:Please resolve a debate for us: If an aircraft travelling at 80mph goes into a 30degree co-ordinated turn, will the radius of the turn be greater or less than the same aircraft, under the same conditions at 160mph. ?

This of course applies to fixed wings and gyro's alike.

We've contemplated lift vectors and inertia and have no conclusive answer.... please help?
For the same angle of bank the turn radius will be larger the higher the speed, that is why a microlight can "turn on a dime" while a jet fighter uses the whole sky for the same turn.

In your example double the speed will produce a turn +- double the radius, assuming a 1G, co-ordinated turn in both cases.

Fly safe,
Rudi
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DieselFan
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Postby DieselFan » Tue Oct 30, 2007 11:49 am

Unless of course you tried to turn with rudder only and are talking about a 30 degree angle when view from above, then you'd have to consider many things like aerodynamics, thrust vectoring etc, you'd also soon get to a speed where you'd just slide with such minimal actual turning that you'd run out of fuel and have to turn using banking to catch that topless merc... :twisted:
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Morph
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Postby Morph » Wed Nov 07, 2007 3:19 pm

Check here for the calculation

http://www.pilotfriend.com/calcs/calcul ... ulator.htm

80mph 30 deg turn will take 40 seconds for a 360 at have a diameter of 1488 feet

160mph 30 deg will take 80 seconds for a 360 and a diameter of 5955 feet, much more.
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priester
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Re: Quick Question

Postby priester » Fri Nov 09, 2007 7:47 pm

Rudix wrote:
JetRanger wrote:Please resolve a debate for us: If an aircraft travelling at 80mph goes into a 30degree co-ordinated turn, will the radius of the turn be greater or less than the same aircraft, under the same conditions at 160mph. ?

This of course applies to fixed wings and gyro's alike.

We've contemplated lift vectors and inertia and have no conclusive answer.... please help?
For the same angle of bank the turn radius will be larger the higher the speed, that is why a microlight can "turn on a dime" while a jet fighter uses the whole sky for the same turn.

In your example double the speed will produce a turn +- double the radius, assuming a 1G, co-ordinated turn in both cases.

Fly safe,
Rudi
A 1G turn is not possible :lol:
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