Theory of a rotary take off?
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Theory of a rotary take off?
I've commited lots of aviodomy in fixed wing - and was recently wondering about going for a rotary hour or two. Made me wonder about some of the differences. Take off sprang to mind - which foot gets all the effort?
Assume you are sat facing forward (always a good start) in a cheap piston trainer with manual throttle, advancing blade coming over your left shoulder. That would encourage the bird to yaw left when increasing power and pulling collective? So, a bit of right foot to get it back again? (or keep it there in the first place - with 'anticipation' being the key).
True/False? Any other bits to take into account when making that first transition from ground to air?
What about the rotary version of steep turns - I suppose "spot turns" would be more common in a vertibird? Does yawing towards the advancing blade cause any bigger (or lesser) drama than yawing towards the retreating blade? Rotor RPM and all that?
Does any of this make sense - or am I just gibbering?
I'd like to understand a bit more than the average muppet if I do go and blow Santas money ($350) on a rotary hour or two - and then, the follow up question - should I do two hours in a Bell47, Scweitzer or 30 minutes in a 206?
Assume you are sat facing forward (always a good start) in a cheap piston trainer with manual throttle, advancing blade coming over your left shoulder. That would encourage the bird to yaw left when increasing power and pulling collective? So, a bit of right foot to get it back again? (or keep it there in the first place - with 'anticipation' being the key).
True/False? Any other bits to take into account when making that first transition from ground to air?
What about the rotary version of steep turns - I suppose "spot turns" would be more common in a vertibird? Does yawing towards the advancing blade cause any bigger (or lesser) drama than yawing towards the retreating blade? Rotor RPM and all that?
Does any of this make sense - or am I just gibbering?
I'd like to understand a bit more than the average muppet if I do go and blow Santas money ($350) on a rotary hour or two - and then, the follow up question - should I do two hours in a Bell47, Scweitzer or 30 minutes in a 206?
Do the Bell 47....fly a real classic...the helicopter that started all this silliness.
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If it's a piston trainer, chances are the blade is advancing over your right shoulder (main rotor blades turning counter-clockwise).
Spot turns - less drama using the "power pedal" - the pedal which increases tail rotor thrust, countering/overcoming main rotor torque.
Money no object, I agree with SAS - I'd choose in this order: Bell 47, Schweizer 300, Enstrom 280, Bell 206, Robinson R44, Robinson R22. I think an hour in a helicopter is better than a half-hour, but I'd only choose the R22 if there were no other options.
And don't worry about gibbering - you'll be doing a lot more of it after your first flight...
Spot turns - less drama using the "power pedal" - the pedal which increases tail rotor thrust, countering/overcoming main rotor torque.
Money no object, I agree with SAS - I'd choose in this order: Bell 47, Schweizer 300, Enstrom 280, Bell 206, Robinson R44, Robinson R22. I think an hour in a helicopter is better than a half-hour, but I'd only choose the R22 if there were no other options.
And don't worry about gibbering - you'll be doing a lot more of it after your first flight...
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Chickenhawk Sample - Robert Mason
The above is a link to a great helicopter book. It has one of the best explanations of helicopter flight control I know. Well worth a read. Start at Page 8 (last paragraph).
Hope this helps.
cl12pv2s
The above is a link to a great helicopter book. It has one of the best explanations of helicopter flight control I know. Well worth a read. Start at Page 8 (last paragraph).
Hope this helps.
cl12pv2s
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Bell 47
Go take a trip in a 47, you'll love it. Have trained in them for a while now worth every penny. Just a real shame they take soooo much money to keep up in the air. I really wish Bell would release a new 47, I'm sure it would be a hit, if the price was right. It's the perfect trainer.
Just my opinion... Have fun anyway.
Darren
Just my opinion... Have fun anyway.
Darren
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Well someone has to take the contrary view. For raw fun on a once off basis, I don't think you can beat the Schweizer. It's a super stable trainer and so you can get all the flying out of your system first, probably even to a passable hover.
But if you find someone who can really fly it, you can then have a real blast in the last half hour. I've done things (under supervision !) that I wouldn't have believed possible in a light heli, including a tailslide auto in a tight turn, an approach and landing without touching the collective from the cruise setting, seemingly vertical torque turns. Just huge !
I've only got about an hour in the 47 and whilst it's a lovely and historic machine, I think you'll have more fun in the 300.
But if you find someone who can really fly it, you can then have a real blast in the last half hour. I've done things (under supervision !) that I wouldn't have believed possible in a light heli, including a tailslide auto in a tight turn, an approach and landing without touching the collective from the cruise setting, seemingly vertical torque turns. Just huge !
I've only got about an hour in the 47 and whilst it's a lovely and historic machine, I think you'll have more fun in the 300.
Combine Operations
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Keygrip,
You can't plan ahead with helicopter controls, mate, you just have to sit there and let your hands and feet do the learning. Bear in mind that the aircraft does not want to fly - its fervent wish is to slam itself into the nearest bit of the Earth. You have to learn what to do in order to prevent that, and that usually involves a micro-miniscule control movement a microsecond before the aircraft starts the aforementioned movement.
Thinking does not come into it - there just isn't the time. Your hands and feet will learn what to do, and cut out the brain completely.
Happy new year.
You can't plan ahead with helicopter controls, mate, you just have to sit there and let your hands and feet do the learning. Bear in mind that the aircraft does not want to fly - its fervent wish is to slam itself into the nearest bit of the Earth. You have to learn what to do in order to prevent that, and that usually involves a micro-miniscule control movement a microsecond before the aircraft starts the aforementioned movement.
Thinking does not come into it - there just isn't the time. Your hands and feet will learn what to do, and cut out the brain completely.
Happy new year.
Re: Theory of a rotary take off?
My flight instuctor explained it very simply -
"Use the cyclic to control yer position over the ground"
"Use the collective to control yer altitude above the ground."
"Use the pedals to control yer heading"
"Use the throttle to keep the little needles in the green arc"
"Do not use them in such a way as to make me spill my coffee!!!"
(He also got upset if, on the first flight of the day, he lost his place in his newspaper.)
This has worked for me for 28 years.
Happy New Year to you all.
"Use the cyclic to control yer position over the ground"
"Use the collective to control yer altitude above the ground."
"Use the pedals to control yer heading"
"Use the throttle to keep the little needles in the green arc"
"Do not use them in such a way as to make me spill my coffee!!!"
(He also got upset if, on the first flight of the day, he lost his place in his newspaper.)
This has worked for me for 28 years.
Happy New Year to you all.
Re: Theory of a rotary take off?
LWAAPAM
Look
Well
Ahead
And
Pick
A
Marker
Look
Well
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And
Pick
A
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Re: Theory of a rotary take off?
Keygrip,
Getting to grips with the controls of a light helicopter at first is much like trying to improve your golf swing, in that filling your mind up with too many facts can be detremental.
However having some of the basics in the back of your mind is advisable.
Small, smooth cyclic inputs are key as the rotor disc is very responsive. Beware of Pilot Induced Oscillations (PIO) due to the time lag between control input and aircraft response. A cyclic control input results in the rotor disc (the plane described by the path that the rotor tips travel (Tip Plane Path)) tilting in the same direction and the aircraft moving accordingly. However the fuselage response occurs sometime after this, once the aircraft gains momentum. This is particularly prevalent in a teetering main rotor system such as that on an R22.
Hence due to this delay a trainee pilot may be tempted to add a further control input in the same direction. This yields excess movement resulting in a knee jerk reaction in the opposite direction. As the momentum of the aircraft cannot be stopped instantaneously, a second opposite input may be applied. This then repeats in the opposite sense. This leads to oscillations in aircraft attitude increasing steadily in amplitude. Definitely to be avoided!
The collective is a position input, this means that collective position demands a set amount of collective pitch and an increase / decrease in this position results in a corresponding proportional increase / decrease in collective pitch.
The anti-torque or yaw pedals are rate inputs in that a pedal input demands a rate of rotation about the vertical axis (Yaw), i.e the larger the input the faster you turn.
The cyclic is an acceleration input. A small input results in a small aircraft acceleration in that direction, and likewise a large input results in a large acceleration.
Above all, the controls are intuitive so if you are co-ordinated just go out there and enjoy!!
Apologies to the seasoned Pros.
Sioux4D
Getting to grips with the controls of a light helicopter at first is much like trying to improve your golf swing, in that filling your mind up with too many facts can be detremental.
However having some of the basics in the back of your mind is advisable.
Small, smooth cyclic inputs are key as the rotor disc is very responsive. Beware of Pilot Induced Oscillations (PIO) due to the time lag between control input and aircraft response. A cyclic control input results in the rotor disc (the plane described by the path that the rotor tips travel (Tip Plane Path)) tilting in the same direction and the aircraft moving accordingly. However the fuselage response occurs sometime after this, once the aircraft gains momentum. This is particularly prevalent in a teetering main rotor system such as that on an R22.
Hence due to this delay a trainee pilot may be tempted to add a further control input in the same direction. This yields excess movement resulting in a knee jerk reaction in the opposite direction. As the momentum of the aircraft cannot be stopped instantaneously, a second opposite input may be applied. This then repeats in the opposite sense. This leads to oscillations in aircraft attitude increasing steadily in amplitude. Definitely to be avoided!
The collective is a position input, this means that collective position demands a set amount of collective pitch and an increase / decrease in this position results in a corresponding proportional increase / decrease in collective pitch.
The anti-torque or yaw pedals are rate inputs in that a pedal input demands a rate of rotation about the vertical axis (Yaw), i.e the larger the input the faster you turn.
The cyclic is an acceleration input. A small input results in a small aircraft acceleration in that direction, and likewise a large input results in a large acceleration.
Above all, the controls are intuitive so if you are co-ordinated just go out there and enjoy!!
Apologies to the seasoned Pros.
Sioux4D
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Re: Theory of a rotary take off?
Farmer1 said it best. All the reading in the world won't prepare you for how to handle the controls. It took me 6-7 hours in an R-22 just to get a stable hover. I didn't think I'd ever catch on but one day it just clicked. Like you, I started out fixed-wing and I'm just now preparing for my helicopter checkride and I've made almost every mistake possible. I'll tell you that from my first ride in the R-22 I was hooked. It's incredibly addictive.
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Re: Theory of a rotary take off?
All the reading in the world won't prepare you for how to handle the controls.
So, Keygrip, if you're the sort of person who thinks the theory will help, maybe it will. It beats me how, but I've seen it happen. So go find a book.
