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General Forums => Aircraft and Vehicles => Topic started by: earl1937 on April 11, 2015, 04:57:40 PM

Title: Climbing Turns in a B-17G
Post by: earl1937 on April 11, 2015, 04:57:40 PM
 :airplane: When in a climbing turn in a B-17 at 120MPH IAS, which will give you the greatest altitude gained in the shortest amount of time, the rate of turn or the radius of turn?
Be surprised how many times I am asked that and just curious what you guys would say!
Title: Re: Climbing Turns in a B-17G
Post by: Zimme83 on April 11, 2015, 05:22:37 PM
Im not sure i understand your question but i would say that a wider turn will give u a better climb rate. But it depends on the situation. Are u doing a spiral climb or only a slight course adjustment?
Title: Re: Climbing Turns in a B-17G
Post by: earl1937 on April 11, 2015, 06:10:11 PM
Im not sure i understand your question but i would say that a wider turn will give u a better climb rate. But it depends on the situation. Are u doing a spiral climb or only a slight course adjustment?
:airplane: My bad! I should have stated a 180 degree climbing turn, sorry!!!!
Title: Re: Climbing Turns in a B-17G
Post by: kvuo75 on April 11, 2015, 06:53:51 PM
seems to me extra rate is g wasted horizontal instead of vertical.

i'd pull up to vy and turn as gently as possible.
Title: Re: Climbing Turns in a B-17G
Post by: Zimme83 on April 11, 2015, 07:11:29 PM
seems to me extra rate is g wasted horizontal instead of vertical.

i'd pull up to vy and turn as gently as possible.

+1. All turns "cost" lift so if gaining alt is most important u should turn as wide as possible.
Title: Re: Climbing Turns in a B-17G
Post by: Gray on April 11, 2015, 08:52:13 PM
Standard rate?
Title: Re: Climbing Turns in a B-17G
Post by: earl1937 on April 12, 2015, 05:31:40 AM
Standard rate?
:airplane: Correct, at any speed, the standard rate of turn produces the most altitude gained in the shorest amount time, with the least amount of sky used to make the 180 degree turn.
The one exception to this would be the old maneuver used on the commercial check ride, which would be the _______ turn. While you would quickly make the 180 degree turn, you certainly wouldn't gain very much altitude when compared to the amount gained by making a standard rate climbing turn.
Just food for thought guys!
Title: Re: Climbing Turns in a B-17G
Post by: kvuo75 on April 12, 2015, 09:35:09 AM
that makes no sense.

the standard rate is completely arbitrary. there's no aerodynamic reason for it. it could just as well be a 8 minute turn or a 30 second turn.
Title: Re: Climbing Turns in a B-17G
Post by: Oldman731 on April 12, 2015, 09:43:50 AM
that makes no sense.

the standard rate is completely arbitrary. there's no aerodynamic reason for it. it could just as well be a 8 minute turn or a 30 second turn.

Nevertheless, a standard rate turn is one that turns three degrees per second, so that a 180 is accomplished in one minute, a 360 in two.

- oldman
Title: Re: Climbing Turns in a B-17G
Post by: Zimme83 on April 12, 2015, 10:14:51 AM
:airplane: Correct, at any speed, the standard rate of turn produces the most altitude gained in the shorest amount time, with the least amount of sky used to make the 180 degree turn.
The one exception to this would be the old maneuver used on the commercial check ride, which would be the _______ turn. While you would quickly make the 180 degree turn, you certainly wouldn't gain very much altitude when compared to the amount gained by making a standard rate climbing turn.
Just food for thought guys!

I'm not sure I'm buying this. Especially when u say "at any speed". Standard rate turns isn't used for aerodynamic reasons but to standardize turns in traffic patterns etc, that's why its called a standard rate turn. The bank angle depends on the speed and at higher speed u will need to pull pretty hard to make a standard rate turn. So no i don't agree on this:
Quote
at any speed, the standard rate of turn produces the most altitude gained in the shorest amount time, with the least amount of sky used to make the 180 degree turn.
Title: Re: Climbing Turns in a B-17G
Post by: colmbo on April 12, 2015, 11:25:55 AM
A 1/2 standard rate turn will l give you more altitude gained in the 180 than the standard rate turn for two reasons:

It takes longer to make the turn

Lower bank angle means more lift "up" instead of "horizontal".
Title: Re: Climbing Turns in a B-17G
Post by: earl1937 on April 13, 2015, 05:45:05 AM
A 1/2 standard rate turn will l give you more altitude gained in the 180 than the standard rate turn for two reasons:

It takes longer to make the turn

Lower bank angle means more lift "up" instead of "horizontal".
:airplane: a standard rate turn will give you the most altitude gained, in the smallest turn radius at a standard rate.
I really didn't ask the question correctly so that is my bad!
a better question would have been, what will give you the least turn radius, with the most altitude gained, while making a 180 degree climbing turn?
The old brain just doesn't work like it used to
Title: Re: Climbing Turns in a B-17G
Post by: earl1937 on April 13, 2015, 05:55:28 AM
I'm not sure I'm buying this. Especially when u say "at any speed". Standard rate turns isn't used for aerodynamic reasons but to standardize turns in traffic patterns etc, that's why its called a standard rate turn. The bank angle depends on the speed and at higher speed u will need to pull pretty hard to make a standard rate turn. So no i don't agree on this:
:airplane: The "needle and ball" indicator serves 4 main purposes:

#1- ATC expects a turn given to a pilot when IFR to be executed in a "standard rate" for aircraft separation when operating in the ATC system IFR. (the exception is when they ask you to expedite a turn)

#2- to assist the pilot in maintaining straight and level flight

#3- to assist the pilot in recovering from unusual attitudes when flying IFR

#4- to assist aircraft in maintaining a orderly holding pattern