maintaiing steep turns

[Kamil]

Hi!

Ok call me a flight sim pilot. . .Why do I find it so hard to maintain zero on the VSI (Or near enough zero) while on a steep turn (45 degree bank)? I seem to be all over the place no matter how much I try esecially on the VSI. Maybe I need a bit more practice and a steady hand. Or is Flight Simulator a bit more sensitive then the real world airpane?

[Lucifer]

Although this will probably go straight to private flying, I'll answer - you are probably looking too much at the VSI; if you pick the correct point on the horizon and monitor the bank angle by the artificial horizon, and height alternately, you will find eventually a 'picture' outside that will give you the correct level flight attitude for a steep turn.

[jsf]

Although this will probably go straight to private flying, I'll answer - you are probably looking too much at the VSI; if you pick the correct point on the horizon and monitor the bank angle by the artificial horizon, and height alternately, you will find eventually a 'picture' outside that will give you the correct level flight attitude for a steep turn.

Spooky <img src="smile.gif" border="0">

[DB6]

Are you talking about a flight simulator or a real aircraft? In the real aircraft case a continuous lookout-attitude-instruments scan is the key, with the majority of the time spent looking out, primarily in the direction of the turn, integrating the attitude check (AoB and horizon). The instruments (altimeter/VSI, horizon[AoB pointer only], ball and ASI) should be scanned briefly but frequently and changes made to the attitude in response to errors evident on the instruments. Another useful helper is the feeling in your rear end which should be a constant pressure (~1.5 g for a 45 degree AoB). . .If it's a flight simulator you're talking about then just program it to do it for you.

[scroggs]

I could send this to Computer & Internet issues, but they'd probably ignore you. I could send it to Private Flying, but they'd laugh. To be nice, I'll send it to Questions, where you might get more than one answer repeated three times (please don't keep pressing the Add Reply button!).. .You may well be a Wannabe, but that doesn't mean you can use this Forum as a personal encyclopedia. This Forum is for information pertaining to achieving a professional flying licence, or a first commercial flying job, and nothing else. Flying computer flight sims is not a suitable subject.

[ 15 February 2002: Message edited by: Scroggs ]</p>

[Kamil]

Thanks a lot both both of you for replying.

Sorry moderator bro :) <img src="frown.gif" border="0">

[chrishowley]

Thought I'd have a go at answering your question as I reckon you want to know whether:

1. Its your fault your finding steep turns difficult. or. .2. Your sim is not very realistic.

Seems like the sim is doing a decent job of realism. Fact is the steeper the turn the more difficult it is to maintain a constant height. Now I'm no expert on aerodynamics (and would be quite pleased for someone to add the real answer) but I reckon that it will have a lot to do with the fact that at steep angles, minor changes in bank have a larger affect on the amount of lift generated by the wings. Because a steep bank means the wings are producing little lift this means a lot of back pressure on the yoke is needed and this takes quite a lot of judging. I expect this is more difficult with the sim than in reality because of the lack of feel of the computer joystick.

Advice above on looking into the distance is the way to deal with the problem but whether this helps on the sim or not I don't know.

[FL310]

wannabee, try this:. .start a smooth initiation of the turn.. .when coming through 30 deg pull the nose some 2 - 3 degrees further up and (!) increase the power slightly. . .when levelling the wings do the exact opposit, bring back the power and let the nose smoothly go down by the amount you pulled it before.. .As a newbie you may want to neglect the VSI completely during this moneuvre, just watch the altimeter very closely and counteract smoothly to any indication of change.. .Overreaction is the standard problem with all beginners. <img src="smile.gif" border="0">

[overstress]

Any skill demands practice. Lots of practice. Steep turns are a test of flying skill and are very difficult, especially in a FBW Airbus!

If you are in a PC flight sim, forget it. The cues you are using are appropriate only to your PC/joystick setup, not to any aeroplane.

[beardy]

The lift vector from the wing is always perpendicular to the wing. As angle of bank is increased the lift vector moves away from the vertical and the vertical component reduces. The aircraft weight remains the same. To remain in level flight the vertical component of the lift vector must equal the weight of the aircraft. To increase the lift vector increase the angle of attack ( for constant speed ) this may be visualised by easing the nose up a couple of degrees from where it was for level flight wings level. At 60 degrees angle of bank you need twice the lift, the increased AOA will increase drag hence you need more power which MAY have it's own pitching effect which in turn MAY alter the back pressure on the control column.

Incidentally steep turns FBW are a piece of p*ss.

[chrishowley]

Thanks beardy - I was attempting to say this in English!

[Sensible]

And since a co-ordinated turn requires a rudder input as well as a yoke input. The flight sims which I have attempted have had no rudder input and therefore a co-ordinated turn would be impossible anyway! but in any event, flight sims just don't give the same feel as a real aircraft.

[low n' slow]

I've actually never tried steepturns on F/S. . .However, in real life the trick is to compensate gradually for the loss of lift as the bank is increased. As I pass the 30 degree mark on the HSI I add power gradually. Also beyond 30 degrees the rudder will become less efficient. If you consider its position in straight and level flight, it will affect yaw. however the sideways component will decrease as the fin is leaned over as a result of the turn. This further results in a decreased yawing component and an increased pitching component (meaning the position of the nose above the horizon). In the same way, the elevator will gradually take over the rudders role as the turn becomes steeper. The trick is to keep this in mind and pay attention to the effectiveness of the various controllsurfaces. Once you get the feel of this, it is quite easy to start flying on HSI references. By maintaining a point on the HSI, you will automatically maintain the turn. . .Another tip is to not try to correct a steep turn once bank is passed 30 degrees. Abort the turn and start over.

regards/lns

[Icarus Wings]

Most of you dont seem to have any idea of the main reason why you learn to do steep turns. It is for COLLISION AVOIDANCE, therefore look OUTSIDE not stare at the instruments.

[Pegasus77]

What a weird idea, if not utterly nonsense, for collision avoidance? When avoiding a collision I really don't take time to look if I exactly have 60 degrees of bank, and if my VSI is at 0 all the time or if I roll out in exactly 360 degrees...

I've always been taught a steep turn is a good manouvre to get your scanning and flying skills up.

If steep turns would be the thing for collision avoidance, wouldn't TCAS give a steep-turn RA instead of a climb/descent? :) :)

[Icarus Wings]

Pegasus,

That's what i am saying. You dont need to be maintaining exactly 60 degrees of bank, zero on the VSI and to roll out 360degrees in a steep turn, that is just going to distract you from looking for the A/C you are about to hit.. .And i am quite clearly not talking about collision avoidance in an A/C with TCAS but in light aircraft.. .And why would you want to practice steep turns on instruments, shouldn't they all be rate one?

[Pegasus77]

My dear Icarus (boy we're getting mythical here!),

My point was that a steep turn is a training manouevre which is done for training scanning and flying skills. I see no reason anywhere to fly steep turns in any normal flight outside training or examination flights.

During my flight training, I always had to make 2 90 degree lookout turns before entering a steep turn, because of other traffic.

And no, not all IFR turns are rate one. The 320 flies most of it's turns with 25 degree bank, and intercepts the ILS with turns up to 30 degrees. No word there about rate one turns.

But again, collision avoidance has never been a factor in practicing steep turns. Flying a steep bank angle is pretty easy! So that has never been the reason they were practised. The difficult part begins first when you want to maintain altitude <img src="wink.gif" border="0">

[ 19 February 2002: Message edited by: Pegasus77 ]</p>

[Aircraft_Nut9]

wannabapilot

Your experience with PC simulators may have to do with the available resolution on the joystick. The resolution on a 'gameport' joystick is basically one part in 256, over its entire travel, in each of it's two axes. This implies one part in 128 over the travel from stick neutral to full up elevator in the pitch axis (or full aileron in the roll axis). The calibration on some joysticks gives a slightly smaller range than this, typically 1 part in 100 or so.

This leads to a less than smooth control i.e. control is available in 1% jumps only.

If you couple the autopilot on the simulation in altitude hold, it will probably show none of this jerkiness, as the control is not subject to the 1% steps.

Try using the calibrate routines on your joystick and watch how jerky it is for small deviations from stick neutral. Indeed there can be some spread of values around this neutral position. It may be usefull to experiment with different 'dead-zone' settings on the simulator, as these control how the simulator responds to small stick movements from the neutral position.

Hope this is of some help.



<img src="wink.gif" border="0">

[Icarus Wings]

ok pegasus i take your point. I dont know what the speed of a 320 is but 25 degrees of bank may well be a rate one turn for that aircraft as it is dependent on airspeed. As i am sure you know that a rate one turn is calculated by Airspeed/10 +7. (180/10+7=25degrees).

[Icarus Wings]

ok pegasus i take your point. I dont know what the speed of a 320 is but 25 degrees of bank may well be a rate one turn for that aircraft as it is dependent on airspeed. As i am sure you know that a rate one turn is calculated by Airspeed/10 +7. (180/10+7=25degrees).

[Pegasus77]

Airspeed varies between 140 and 340 kts indicated... Flying turns with approx. 25 degrees bank means we actually never fly rate one. Same applies for almost all jet a/c.