R22 Crosswind Limitations
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R22 Crosswind Limitations
Why is it always recommended that we do a left peddle ie for a spot turn, rather than a right peddle turn?? Something to do with tail rotor thrust?
By turning against the torque (ie to the left in a US machine, to the right in a French machine) you are effectively carrying out a power check.
If you have sufficient power to spot turn against the torque, then you will have enough power to spot turn with it. But you won't know this for sure if your first turn is with the torque.
Edited to add: Sorry, just re-read your post. I thought that you were talking about the first spot turn of a flight. After the initial turn, surely if you need to spot-turn to the right then you turn to the right?
If you have sufficient power to spot turn against the torque, then you will have enough power to spot turn with it. But you won't know this for sure if your first turn is with the torque.
Edited to add: Sorry, just re-read your post. I thought that you were talking about the first spot turn of a flight. After the initial turn, surely if you need to spot-turn to the right then you turn to the right?
Originally Posted by A.Agincourt
allanon1980: Imagine high AUM and you allow a turn in the direction of torque, if you allow the rate of turn to increase too much you might get into a situation where you run out of pedal movement/torque/power in trying to correct it. By habitually turning against torque you ensure that a]you are less likely to exceed rate of turn before power limits are reached, and that there is less of a chance of reaching those limits when correcting. b] Imagine you get a nasty blow from the wrong side which wants to increase the rate of turn. More control required. Which offers more control in terms of power margin and control movement limit? Next time you hover - into wind, try turning in both and note the power required and the range of control movement in both directions. The preferential direction of turn varies with type.
Best Wishes
Best Wishes
There must be an echo in here. Ah, if only A.Agincourt could read what I wrote...
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Hi
From a training point of view in some of the earlier lessons some think it a good idea to spot turn using the power pedal (against the torque reaction) because its less likely you build an excessive yaw rate and then not be able to stop quickly, as is possible turning the other way.
When spot turning in a healthy wind its always the turn with the torque reaction that people allow to get a little too quick.
However after a few hours and once completely aware of what your doing turn either way I reckon!
Regards Lplates
From a training point of view in some of the earlier lessons some think it a good idea to spot turn using the power pedal (against the torque reaction) because its less likely you build an excessive yaw rate and then not be able to stop quickly, as is possible turning the other way.
When spot turning in a healthy wind its always the turn with the torque reaction that people allow to get a little too quick.
However after a few hours and once completely aware of what your doing turn either way I reckon!
Regards Lplates
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If you're flying solo then by turning to the left you are putting your tail rotor somewhere that you can see to be clear...
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Left pedal turn to avoid LTE
You do a left pedal turn (on a counter clockwise rotor system) to avoid LTE due to tail rotor vortex ring state. If you have a left crosswind from 210 to 330 a vortex ring state may form.
If you would do a spot turn to the right, you would aggravate the TR vortex ring state followed by weathercock instability....
http://www.dynamicflight.com/aerodyn...loss_tail_eff/
If you would do a spot turn to the right, you would aggravate the TR vortex ring state followed by weathercock instability....
http://www.dynamicflight.com/aerodyn...loss_tail_eff/
Last edited by Runway101; 6th May 2008 at 04:41. Reason: added link
It is because it is a gutless, underpowered heap of junk unless you fly it solo with low fuel. However, lots of people seem to think exceeding the MAP is fine and use the extra power to make up for poor handling skills.
The reason for turning left is that you normally hover into wind and carry out spot turns or lookout turns with the intention of returning to that condition. As you turn past crosswind towards the downwind position, you are likely to see the rate of turn increase due to weathercocking and may apply considerable opposite pedal to arrest this rate of turn. Not a problem if you are turning left since you would use right pedal to stop the turn - but if you are turning right, you will use left (power) pedal to stop the turn and may see a large spike in Torque (MAP) which may exceed the aircraft limitations.
Only Jetrangers seem to have problems with LTE (due to the size of the TR) and I think the rate of turn required to achieve vortex ring conditions on a TR would be far higher than most pilots would ever achieve in a spot turn.
The reason for turning left is that you normally hover into wind and carry out spot turns or lookout turns with the intention of returning to that condition. As you turn past crosswind towards the downwind position, you are likely to see the rate of turn increase due to weathercocking and may apply considerable opposite pedal to arrest this rate of turn. Not a problem if you are turning left since you would use right pedal to stop the turn - but if you are turning right, you will use left (power) pedal to stop the turn and may see a large spike in Torque (MAP) which may exceed the aircraft limitations.
Only Jetrangers seem to have problems with LTE (due to the size of the TR) and I think the rate of turn required to achieve vortex ring conditions on a TR would be far higher than most pilots would ever achieve in a spot turn.
