Holding altitude during turns
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Pulling back while in a steep turn where height is being lost (so a spiral dive, then) will (as I said) result in more 'G' and the airspeed winding up, the rate of height loss increasing, so even more 'G' and even more speed, until the aeroplane breaks. Adding power will just make the above happen more quickly.
The very first thing to do to recover from a spiral dive is LEVEL THE WINGS!
Pulling back and adding power will only correct height loss in gentle turns, not in steep ones. Aren't steep turns part of the PPL any more? All of this is (was?) covered in the syllabus.
The very first thing to do to recover from a spiral dive is LEVEL THE WINGS!
Pulling back and adding power will only correct height loss in gentle turns, not in steep ones. Aren't steep turns part of the PPL any more? All of this is (was?) covered in the syllabus.
Last edited by Shaggy Sheep Driver; 14th Sep 2012 at 19:49.
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Aren't steep turns part of the PPL any more? All of this is (was?) covered in the syllabus
As my FI from my PPL advised me way back in the early 90's "Every day is a school day"
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The very first thing to do to recover from a spiral dive is LEVEL THE WINGS!
If you have a significant amount of pitch (G's) in, and roll without unloading that pitch, you increase the loading on the wing root, possibly to the point of exceeding its design limits. In the ultimate case, the wing may even break off. This is called wing root bending effect and the problem is that it doesn't show on a G meter. Flying below Va also doesn't protect you from it.
Moderator
The OP talked about a 50' loss of height. It is entirely appropriate to use more back pressure and power, and maybe reduce bank angle slightly. The loss of 50' is not a spiral dive of death requiring the action you describe,
What are we talking about here anyway? To me, a steep turn is a stabilized maneuver, which can be held indefinitely with 60 degrees of bank, and 2 G being pulled. No wings coming off, or speed building up.
This is not something that you'll ever be doing as a part of an IFR or other ATC required procedure, so don't be worried about them caring about your precision. It won't be something that most people on this forum will be doing in formation, so you're not worried about spacing by referring to altimeters, and it is well within the capability of any certified light aircraft. If your personal desire for precision flying dictates that your should get the 50 feet back, by all means fix it... But, for my understanding of the standards for a PPL or CPL flight test, you're still within tolerance - You've got to be very smooth, and familiar with the aircraft, and paying close attention to go all the way around that way, and stay within 50 feet. I recall doing this for my CPL a few years back, in my C 150 I have 2800 hours flying. I did it okay, but unusual attention was required, despite my familiarity with the plane. I was also required to demonstrate a co-ordinated rollout within 5 degrees of heading.
If you are in a 60 degree banked turn, and you loose 50 feet, and you want it back, pulling 2.1 G, and adding a bit of power will get you out, with some precise flying. no worries about the plane coming apart. If, from a 60 degree banked turn, you slip into a spiral dive, well, that's well beyond the original question, and warrants a different answer. Pilots attempting to maintain control of certified aircraft within their limitations don't pull wings off them.
Other than for flying competition aerobatics, if you ever really need to do a 60 degree banked turn, it'll only need to be half the way around, and no one is going to be watching for 50' of altitude change.
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Yes, of course one would unload first to avoid 'rolling G', and the power would be pulled simultaneously. In a max rate turn, attitude is controlled with bank angle, rather than elevator.
But yes, I'd missed that it was only 50'. Not a serious height loss in a MRT, so not a spiral.
But yes, I'd missed that it was only 50'. Not a serious height loss in a MRT, so not a spiral.
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This is quite a good description of a spiral dive and not what I was referring to!
http://www.skywalker.ca/Flying_Stori...SpiralDive.PDF
http://www.skywalker.ca/Flying_Stori...SpiralDive.PDF
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Pilot Dar
To try and execute the most perfect steep turn you can execute you have to have a reference altitude!
If you fail and end up low on that reference altitude you should not decide to make the newer lower altitude a new reference altitude? If you do the next time round you will again be setting another new reference altitude to compensate for the pilots lack of skills!
In my book you have one reference altitude not 2 or 3 or 4 ; )
Pace
To try and execute the most perfect steep turn you can execute you have to have a reference altitude!
If you fail and end up low on that reference altitude you should not decide to make the newer lower altitude a new reference altitude? If you do the next time round you will again be setting another new reference altitude to compensate for the pilots lack of skills!
In my book you have one reference altitude not 2 or 3 or 4 ; )
Pace
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Shaggy Sheep
Just a question? Do you believe its possible to do a steep turn in the descent without being in a spiral dive and if the answer is yes how would you do it?
Because from what you say any descending steep turn is a spiral dive!
Pace
Just a question? Do you believe its possible to do a steep turn in the descent without being in a spiral dive and if the answer is yes how would you do it?
Because from what you say any descending steep turn is a spiral dive!
Pace
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you should not decide to make the newer lower altitude a new reference altitude?
Yes, one can happily steep turn in the descent, but you knew that. I used to get the jump plane down in a stabilized 2+G spiral the whole way. I kept the power up a bit to prevent shock cooling, but made good time down to save the jump club a bit of cost.
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Yes, one can happily steep turn in the descent, but you knew that. I used to get the jump plane down in a stabilized 2+G spiral the whole way. I kept the power up a bit to prevent shock cooling, but made good time down to save the jump club a bit of cost.
Referring to the original post, the whole point is to get to a level of skill where you can maintain a climbing, level or descending turn without all your attention being focussed on it. This will really help when doing things like bad weather circuits or instrument approaches, where unchecked altitude loss can kill you...
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Instead of reading this stuff,go fly with an Instructor. Until you have,roll out of the turn and don't experiment until you are sure and confident.(And I don't care if it's only 50ft!)
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On the other hand...
Call me unprofessional but this kind of thing is good fun and can be wholly deliberate at all sorts of bank angles, rates of climb/descent, and different speeds. Just know the limits of the aeroplane, stick to the limits you impose on yourself, and know how to recover from anything that looks astray.
We all know what +2G feels like in a steep turn, and we all should know what the G limitations are for our mounts; somewhere between -3 and +6 for the usual GA types. As long as she's not put into a position prohibited by the POH (knife edge flight for example) I see little wrong with safely* getting into a steep turn and pushing or pulling a smidge, or adding reducing power to see what happens. Just keep one eye outside and one eye on whichever thing is beginning to look uncomfortable (RPM gauge?) and calm her down.
*Education via full/part aerobatic course, instructor demonstration, etc.
We all know what +2G feels like in a steep turn, and we all should know what the G limitations are for our mounts; somewhere between -3 and +6 for the usual GA types. As long as she's not put into a position prohibited by the POH (knife edge flight for example) I see little wrong with safely* getting into a steep turn and pushing or pulling a smidge, or adding reducing power to see what happens. Just keep one eye outside and one eye on whichever thing is beginning to look uncomfortable (RPM gauge?) and calm her down.
*Education via full/part aerobatic course, instructor demonstration, etc.
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In the Chipmunk you sit on the centreline of the aeroplane, so can nail the horizon to the spinner. Helps maintain accuracy in turns both in height maintenance and rudder co-ordination.
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Another thing which hasn't been mentioned, is the need for consistently good trimming.
A steep turn at a certain angle of bank requires a certain pull on the stick to remain level. How hard to pull is dependent on the angle of bank, airspeed and the aircraft itself. But apart from those factors, there is little else that influences the amount of pull required. So after some practice you should be able to execute a level steep turn consistently without having to refer to instruments at all.
However, if your trim settings are incorrect, then this introduces another unknown variable, and your altitude will be all over the place. In both level flight (but that's normally easier to pick up and correct) and in any kind of turn.
A steep turn at a certain angle of bank requires a certain pull on the stick to remain level. How hard to pull is dependent on the angle of bank, airspeed and the aircraft itself. But apart from those factors, there is little else that influences the amount of pull required. So after some practice you should be able to execute a level steep turn consistently without having to refer to instruments at all.
However, if your trim settings are incorrect, then this introduces another unknown variable, and your altitude will be all over the place. In both level flight (but that's normally easier to pick up and correct) and in any kind of turn.
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... and we all should know what the G limitations are for our mounts; somewhere between -3 and +6 for the usual GA types.
.
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What I found very helpful when learning to fly was being taught that every turn was an ACELERATION.....
Not immediately obvious but if you think about it is logical. Those of us who are taught aerobatics appreciate this more but every level turn involves an increase in angle of attack and with it drag. To counter the drag more thrust is required to maintain airspeed and if airspeed is lost so is lift and hence you descend.
If you instinctively add a little power as you roll into the turn at the same time as you increase pitch, then the turn stabilises without loss of height and (if you have enough power and limit the AOB) you can also maintain your initial airspeed, and with it the lift you need to stay level.
The same is true in a car. The deflection of the front wheels to turn increased their rolling resistance, if you gently add power in the turn (assuming you have entered the corner at the correct speed!) you can "feel" the car in much better balance. Slowing in the turn is bad as it loads the outside front wheel while lightening the load on the other wheels, which in turn reduces their grip......
Just my 2c's.
MB
Not immediately obvious but if you think about it is logical. Those of us who are taught aerobatics appreciate this more but every level turn involves an increase in angle of attack and with it drag. To counter the drag more thrust is required to maintain airspeed and if airspeed is lost so is lift and hence you descend.
If you instinctively add a little power as you roll into the turn at the same time as you increase pitch, then the turn stabilises without loss of height and (if you have enough power and limit the AOB) you can also maintain your initial airspeed, and with it the lift you need to stay level.
The same is true in a car. The deflection of the front wheels to turn increased their rolling resistance, if you gently add power in the turn (assuming you have entered the corner at the correct speed!) you can "feel" the car in much better balance. Slowing in the turn is bad as it loads the outside front wheel while lightening the load on the other wheels, which in turn reduces their grip......
Just my 2c's.
MB
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What "usual GA types" are you referring to? The usual GA types I am aware of (e.g., C152, DV20) are limited to about -2 and +4g .
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Hi All, not many of the replies so far have mentioned the Power Control
during turns... I am sure the correct proceedure is to ADD POWER proportional to the AOB. So for instance...
30 deg AoB fly at cruise setting 60% Power
45 deg AoB increase power to say 2500rpm 80% Power
60+ deg AoB increase power to 100%
That way the increased drag will not cause any loss of kinetic
or potential energy.
Sure this is mentioned somewhere in the PPL sylabus.
Pete
during turns... I am sure the correct proceedure is to ADD POWER proportional to the AOB. So for instance...
30 deg AoB fly at cruise setting 60% Power
45 deg AoB increase power to say 2500rpm 80% Power
60+ deg AoB increase power to 100%
That way the increased drag will not cause any loss of kinetic
or potential energy.
Sure this is mentioned somewhere in the PPL sylabus.
Pete
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The power control as you put it will vary from make to make and engine power available rather than fitting certain power settings as a percentage per degree bank.
You should be able to feel what is required much more fun than fly by numbers
because then you fly with your soul and your instincts!
Pace
You should be able to feel what is required much more fun than fly by numbers
because then you fly with your soul and your instincts!Pace
Last edited by Pace; 18th Sep 2012 at 12:12.