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In a climb

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Marko created the topic: In a climb

Hi all , so in a climbing turn (say for argument a spiral climb)you have to constantly roll out in order to keep the angle of bank in relation to the horizon. So I presume if you just constantly stared at the artificial horizon and kept the pointer at the required angle With inputs on the yolk this would keep the required angle of bank all the way up in a climbing turn.is this correct.But if you kept on rolling out then you would eventually become level is this no so?
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  • John.Heddles
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John.Heddles replied the topic: In a climb

Not quite - in a turn you will have set up the attitude and control loads required to maintain whatever it is you are setting out to do. There should be no rolling out the turn as you go. Apart from minor corrections for things such as the odd bit of turbulence and such, you really don't have all that much to do other than monitor things.

Just staring (fixating) on any instrument is not a good strategy for a variety of reasons - I presume that you have yet to do any I/F work in your training ? If you are flying contact, your view out the window will be a constantly varying scan, if you are flying instruments, likewise, on the panel.

The more interesting matter relates to the question posted. Some subtlety there. TAS is a constraint on turn performance, If you are maintaining bank and IAS during the climb, then the TAS will be increasing progressively, if slowly, and the rate will reduce and the radius increase. For this consideration, (b) would be the answer. If you ignore the very small effect for a light aircraft, (d) would be the answer.

Engineering specialist in aircraft performance and weight control.
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Marko replied the topic: In a climb

Hi John question 13 and the idea of staring at the artificial horizon
Was to confirm that the angle of bank in relation to the horizon stayed the same in relation to the horizon.it just lead to another line of thinking in relation to the attached description of a climbing turn
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John.Heddles replied the topic: In a climb

.. the idea of staring at the artificial horizon .. Was to confirm that the angle of bank in relation to the horizon stayed the same

Yes, I know what you mean. However, please put that though right out of your mind. If you go on to I/F work, it will get you into REAL trouble. Keep in mind, also, that on limited panel, you don't have an A/H.

Regarding the scan of the page from, I guess, Bob's book. Again, yes, the overbanking problem often is discussed in terms of having to roll out. However, read the last sentence in the paragraph.

Engineering specialist in aircraft performance and weight control.
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Marko replied the topic: In a climb

Sorry John I’m still not getting it.Would continually rolling out of a climbing turn bring you level
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Marko replied the topic: In a climb

Because if you held the same initial bank with no correction From then on in according to the book the angle would steepen.is this correct
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Marko replied the topic: In a climb

Okay I might of got it please tell me if this is correct.Do you initiate the climbing turn by off setting the yolk And then returning it to the neutral position once the turn and climb has commenced.The aircraft then Steepens the bank On its own accord ,you then displace the yolk to regain the correct bank angle and return the yolk to neutral.I had in my mind that you kept on displacing the yolk and therefore levelling the aircraft and running out of full deflection of the yolk
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  • John.Heddles
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John.Heddles replied the topic: In a climb

Would continually rolling out of a climbing turn bring you level

Of course it would bring your wings level. But that has little to do with executing a steady turn.

Because if you held the same initial bank with no correction From then on in according to the book the angle would steepen.is this correct

The book is trying to tell a generic, usual story, and that's all fine. Sometimes, the necessary simplifications and generalisations cause a bit of confusion along the way. Just the way things are in the learning processes.

Try thinking about it this way: if you roll into a turn and then let go of the control, the aircraft will do what it wants to do as a consequence of the particular design. That may well be to roll further into a steepening bank angle and finally end up in a spiral dive. - all depends on the detail design and flight characteristics of the aircraft - this would be a very typical response. We refer to this sort of problem as a "stick free" characteristic.

However, if you hold (freeze) the initial stick input you used to get to the target bank angle with no correction then you are looking at a stick fixed characteristic.

(What we normally do is roll in, hit the target angle and, simultaneously, ease some of the aileron deflection off to reduce the initial rolling moment input. If we did actually hold the initial roll input, we probably would continue rolling and cause ourselves some problems).

That (stick fixed) probably will be somewhat different in character but, again, will depend strongly on the detail aircraft design. Generally speaking, so long as the roll characteristics are not all that rapid in change, we are not too fussed about the basic aircraft's response in roll.

What we do, however, in practice, is roll in to a target bank angle and then modulate the stick input, as required, to maintain the target bank angle. This we just do simply adjusting the control load by pressuring the horn/stick left or right as necessary to prevent undesired additional roll in either direction. The routine aim in a steady turn (level, climbing, descending .. whatever) is to maintain the bank angle.

Do you initiate the climbing turn by off setting the yolk and then returning it to the neutral position once the turn and climb has commenced.

A minor aside - "yoke" rather than "yolk")

No. Roll in to the target bank and then modulate the stick pressure to maintain the bank angle. Airbus is a bit different but probably not all that relevant to this forum.

The aircraft then Steepens the bank On its own accord

Not necessarily if you return the stick to the central position. That will remove the roll moment input caused by the initial aileron movement. What the aircraft will do will depend on the aircraft design.

you then displace the yolk to regain the correct bank angle and return the yolk to neutral.

Not conventionally. I presume that you have not yet started the actual stick and rudder flying training ?

I had in my mind that you kept on displacing the yolk and therefore levelling the aircraft and running out of full deflection of the yolk

Not the way things work. When you start some aircraft pushing and pulling it will all become much clearer, very quickly. The other thing which makes for confusion in the initial stages is that you are playing with three controls (which may work just a little bit differently in different aircraft). It takes the first flight to get your head around the basics but then it gets pretty straightforward.

Very much a case of patting your head and rubbing your tummy at the same time, I fear.

Engineering specialist in aircraft performance and weight control.
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Marko replied the topic: In a climb

Thanks again John for your quick response as usual and yes you are correct I haven’t started the practical part of training as yet trying to get the exams out of the way firstAs you can see this has its drawbacks .and yes the yolks on me lol
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John.Heddles replied the topic: In a climb

trying to get the exams out of the way first

A good strategy as this then allows you to progress in your flying at the maximum rate commensurate with money, availability etc.

Especially for students self funding, having everything which could create a roadblock out of the way can see you taking either the minimum, or much closer to the minimum, hours to get the ticket and that is a lot of dollars, these days. The other thing I would recommend is to have all the dollars required put away before starting on the flying so funding doesn't become a major roadblock.

Yes, the understanding sometimes can present a challenge but it's doable - either exploit this forum by asking questions or grab some other books to read in addition on the basis that we all learn a little differently and often all it takes is something to be presented just a little differently for it to "click".

Engineering specialist in aircraft performance and weight control.
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