Which side?
Nemo Me Impune Lacessit
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Angels60 you are totally incorrect regarding FW LHS, Groundloop is on the money and it is all to do with following line features on the ground in poor weather and keeping them on the left hand side to avoid a head on, goes back a long, long way. Troll on. (I read somewhere that more road traffic in this World drives on the LEFT rather than the right).
gr8shandini - I used to fly the Bell47G, pilot flying sits on the left and am right handed so know what you mean about ease of controlling whilst changing frequencies etc.! But you do get used to it.
gr8shandini - I used to fly the Bell47G, pilot flying sits on the left and am right handed so know what you mean about ease of controlling whilst changing frequencies etc.! But you do get used to it.
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Say again Para...didn't catch it...
Ok...for those that don't fly helos in here, if you fly a helicopter fast enough, the retreating blade creates less lift then the advancing blade.. hence the roll effect tward the retreating blade.
Try to imagine the wing on the right side is creating more lift then on the left...hence the roll effect...the faster you go, the more roll tendency...
The faster you go in a helo, the more your rolling effect tward the side of the retreating blade...actual helo pilots help me out here. Trim counteracts this, along with the pilot sitting on the side of advancing blade, or even fuel tank position from what I hear...
Have you ever seen that little wing on the tail of a Jet Ranger for instance, and wondered why a Jet Ranger needs a little wing?
Since US helos typicaly have a counterclockwise main rotor path, as seen from above, the advancing blade is on the right...and viola...most helos have the pilot sitting on the right side, unless the blades turn the other way...
If you guys want I can go to book and grab some quotes and references...or start dragging some guys from the helo forum in here..
Ok...for those that don't fly helos in here, if you fly a helicopter fast enough, the retreating blade creates less lift then the advancing blade.. hence the roll effect tward the retreating blade.
Try to imagine the wing on the right side is creating more lift then on the left...hence the roll effect...the faster you go, the more roll tendency...
The faster you go in a helo, the more your rolling effect tward the side of the retreating blade...actual helo pilots help me out here. Trim counteracts this, along with the pilot sitting on the side of advancing blade, or even fuel tank position from what I hear...
Have you ever seen that little wing on the tail of a Jet Ranger for instance, and wondered why a Jet Ranger needs a little wing?
Since US helos typicaly have a counterclockwise main rotor path, as seen from above, the advancing blade is on the right...and viola...most helos have the pilot sitting on the right side, unless the blades turn the other way...
If you guys want I can go to book and grab some quotes and references...or start dragging some guys from the helo forum in here..
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I know all about dissymmetry of lift. Quote away. However, it doesn't change the fact that the moment produced by sitting on one side or the other is miniscule compared to that produced by the cyclic control.
And for the record, the stabilizer (or "little wing") on the back of the B206 and most other helos is there to reduce drag by keeping the fuselage more or less aligned with the airstream in cruise. If you look closely, they're heavily cambered and it's easy to tell that they're both providing a downward force to counter the forward pitching moment imparted by the rotor disc in forward flight. They're small because they're pretty far from the longitudinal CG. If they had to provide a lateral force, they'd have to be much bigger.
Well, it's pretty obvious that no one is changing Angels' mind so that's about all I have to say on this subject. I do have one parting question, though: So if you're carrying a passenger, do you make them sit behind you, or are they allowed to sit up front?
And for the record, the stabilizer (or "little wing") on the back of the B206 and most other helos is there to reduce drag by keeping the fuselage more or less aligned with the airstream in cruise. If you look closely, they're heavily cambered and it's easy to tell that they're both providing a downward force to counter the forward pitching moment imparted by the rotor disc in forward flight. They're small because they're pretty far from the longitudinal CG. If they had to provide a lateral force, they'd have to be much bigger.
Well, it's pretty obvious that no one is changing Angels' mind so that's about all I have to say on this subject. I do have one parting question, though: So if you're carrying a passenger, do you make them sit behind you, or are they allowed to sit up front?
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Great6Sandini
Page 65 / Chapter 9 Basic Helcopter Handbook : Hazards of Flight
AC-61-13B
.....The airflow over the retreating blade of the helicopter slows down as the forward airspeed of the helicopter increases: the airflow over the advancing blade spees up as forwards airspeed of the helicopter increases...
The major warnings of approaching retreating blade stall conditions in the order in while they will generaly be experienced are:
- Abnormal vibrations
- Pitch up of the nose ..............one reason why that little wing is there
- Tendency for the helicopter to ROLL
When one blade is losing lift, the other is gaining lift...that's called.....??
Page 65 / Chapter 9 Basic Helcopter Handbook : Hazards of Flight
AC-61-13B
.....The airflow over the retreating blade of the helicopter slows down as the forward airspeed of the helicopter increases: the airflow over the advancing blade spees up as forwards airspeed of the helicopter increases...
The major warnings of approaching retreating blade stall conditions in the order in while they will generaly be experienced are:
- Abnormal vibrations
- Pitch up of the nose ..............one reason why that little wing is there
- Tendency for the helicopter to ROLL
When one blade is losing lift, the other is gaining lift...that's called.....??
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or start dragging some guys from the helo forum in here
Angels - that last post did it for me. The horizontal stabiliser on a helo has got absolutely nothing to do with controlling the pitch up tendency with retreating blade stall. Read up on Prouty if you want to argue the toss, or get Nick Lappos to put his twopenny worth in here.
the advancing blade is on the right...and viola...most helos have the pilot sitting on the right side
Why helo guys sit on the right has always been a subject of much discussion and there are many thoughts but little concrete. The best theory I have come across and think most likely is that the first helos had the one and only collective lever mounted between the two seats. That meant the left seat guy flew with left hand on the cyclic and right hand on the collective, the right seat guy of course it was the reverse, vis right hand cyclic, left hand collective. It was said that Igor preferred to sit in the left seat when training the new boys, and so the new pilots (in the right seat) grew accustomed and naturally preferred that position when they were let loose to the squadrons. Hey presto, a convention is born.
PS 20,000 hours helo and don't pretend to know everything, but do know a little bit.
Uh--Angel--I have in excess of 6,000 hours in the Astar--and many more in other helicopters. The position of the pilot has NOTHING to do with aerodynamics, but more of convenience. The Astar I flew had the PIC on the left because we flew clockwise around an island, and wanted to fit two passenger seats up front to view the island.
We bought our Astars new form the factory with the PIC on the right and then paid to have the aircraft modified for left hand PIC.
We bought our Astars new form the factory with the PIC on the right and then paid to have the aircraft modified for left hand PIC.
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To those of you who may be wondering what the horizontal stabiliser on a helo does. The primary purpose of the horizontal stabiliser is to give the helicopter stability in pitch. Both the helicopter rotor and its fuselage have an inherent negative stability derivative in pitch and the stabiliser helps to give the helicopter better overall handling qualities. The large surface area of the fuselage ahead of the centre of gravity has a powerful negative stability influence.
The source material (an oustanding book) is "Principles of Helicopter Aerodynamics" by J. Gordon Leishman (Cambridge Aerospace Series) and a lengthy discussion can be found on page 311 at http://books.google.com.au/books?hl=...QYYA#PPA311,M1
I would advise caution in the referenced materials use as Angel has not put his seal of approval on it. A poster on another thread put it rather well by saying "I have absolutely no sense of humor when it comes to those who disseminate erroneous information under the guise of being factual. These are understood characteristics in politics. They are dangerous characteristics in engineering." And I might add aviation.
The source material (an oustanding book) is "Principles of Helicopter Aerodynamics" by J. Gordon Leishman (Cambridge Aerospace Series) and a lengthy discussion can be found on page 311 at http://books.google.com.au/books?hl=...QYYA#PPA311,M1
I would advise caution in the referenced materials use as Angel has not put his seal of approval on it. A poster on another thread put it rather well by saying "I have absolutely no sense of humor when it comes to those who disseminate erroneous information under the guise of being factual. These are understood characteristics in politics. They are dangerous characteristics in engineering." And I might add aviation.
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Sorry to throw a little water on you Brian...
But, with the RAF SAR Wessex (now retired) & Sea King the Commander sits in the right seat. (Had a Nav. in the left seat of the Wessex)
One main reason was the hoist was on that side.
Regards.
O
But, with the RAF SAR Wessex (now retired) & Sea King the Commander sits in the right seat. (Had a Nav. in the left seat of the Wessex)
One main reason was the hoist was on that side.
Regards.
O
Angels - your casual dismissal of other peoples' posts because they do not agree with you marks you out as either a wind-up merchant just causing trouble or someone who really doesn't know anything about helicopters other than what you have read from a book.
Brian is a well respected member of the rotorheads forum and his posts are always accurate and well informed.
With some ineveitable exceptions, pilots in helicopters fly in the right hand seat even at maximum speed in an ASTAR.
Compared to some I am still a newbie on helicopters but after 26 years and 7000 hours in helicopters (19 years as a QHI) I do have a vague idea of what happens in them.
Keep on fishing
Brian is a well respected member of the rotorheads forum and his posts are always accurate and well informed.
With some ineveitable exceptions, pilots in helicopters fly in the right hand seat even at maximum speed in an ASTAR.
Compared to some I am still a newbie on helicopters but after 26 years and 7000 hours in helicopters (19 years as a QHI) I do have a vague idea of what happens in them.
Keep on fishing
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I cant hold back anymore!! A slab and swing wing driver speaks up!!
My Prefence in a fixed wing is the sitting on the LHS for the airmanship aspect (turn right so can see conflicting aircraft all the time as you pass each other etc), its also easier when reaching for your favourite item on the cheeseboard!!
My preference for sitting in a Helicopter is the LHS.
This has nothing to do with which way the main rotors happen to turn but simply the collective lever (up/down!) is always on the left. Apart from the hassle of having to lift ones leg over it when entering/exiting the aircraft it is far more comfortable to sit on the LHS. Unless you are tall or have arms like an orangutan sitting on the right side and watching an external load becomes very uncomfortable very quickly. When sitting on the left you can lean out over the collective and even reference power/pitch by feeling it against your thigh etc. over on the right you are streching your left arm way out to reach and hold the collective whilst straining your neck to the right look out and down at the load/obstacles below.
(Also on the LHS having the Collective on the left guards it from accidental inputs from passengers feet/arms arse or handbag)etc.
Now just to prove the point about aerodynamics and retreating blade stall having no relevence to seating position:
Eurocopter 350 series BA,B2,B3, series pilot sits RHS
Eurocopter 350 B4 series Pilot sits on LHS.
Both machines have identical blades, rotorhead and transmission
both machine blades turn clockwise. not an issue!!
Also
military H500 pilot sits RHS
Civilian H500 pilot sits LHS otherwise identical machine (and rotors) QED
P.S.
Only reason the B4 pilot now sits on LHS is because that was what most pilots have asked for (as well as a twist throttle by the way)
Only reason Military put pilot on RHS in H500 was so when they progressed to the huey they were used to sitting on the RHS.
My preference for sitting in a Helicopter is the LHS.
This has nothing to do with which way the main rotors happen to turn but simply the collective lever (up/down!) is always on the left. Apart from the hassle of having to lift ones leg over it when entering/exiting the aircraft it is far more comfortable to sit on the LHS. Unless you are tall or have arms like an orangutan sitting on the right side and watching an external load becomes very uncomfortable very quickly. When sitting on the left you can lean out over the collective and even reference power/pitch by feeling it against your thigh etc. over on the right you are streching your left arm way out to reach and hold the collective whilst straining your neck to the right look out and down at the load/obstacles below.
(Also on the LHS having the Collective on the left guards it from accidental inputs from passengers feet/arms arse or handbag)etc.
Now just to prove the point about aerodynamics and retreating blade stall having no relevence to seating position:
Eurocopter 350 series BA,B2,B3, series pilot sits RHS
Eurocopter 350 B4 series Pilot sits on LHS.
Both machines have identical blades, rotorhead and transmission
both machine blades turn clockwise. not an issue!!
Also
military H500 pilot sits RHS
Civilian H500 pilot sits LHS otherwise identical machine (and rotors) QED
P.S.
Only reason the B4 pilot now sits on LHS is because that was what most pilots have asked for (as well as a twist throttle by the way)
Only reason Military put pilot on RHS in H500 was so when they progressed to the huey they were used to sitting on the RHS.
Last edited by Heli-phile; 25th May 2008 at 06:31. Reason: cant sprel!!
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Angels in response to your ”
.....now what happens when you sit on the right side of an Astar and go really fast..hmmmmm?” if you are talking about retreating blade stall you would eventually pitch up and roll right. If you sat in the left seat you would still roll right. It makes No difference where you fly from as far as aerodynamics are concerned. Long line pilots will routinely fly a B212 or a S61 from the left because the visibility during a hover is better. Now the MD530 is flown from the left….why is that?
.....now what happens when you sit on the right side of an Astar and go really fast..hmmmmm?” if you are talking about retreating blade stall you would eventually pitch up and roll right. If you sat in the left seat you would still roll right. It makes No difference where you fly from as far as aerodynamics are concerned. Long line pilots will routinely fly a B212 or a S61 from the left because the visibility during a hover is better. Now the MD530 is flown from the left….why is that?
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I think Angels has a new identity aka Iflymach85
That has to be about the most laughable statement I've yet seen.
SNS3Guppy - You had him taped early. Walter Mitty reincarnated, or maybe his wingman.
On a long x-country, going fast, not a bad thing to ease that cyclic force by sitting on the opposite side of the roll depending on the helo your flying
SNS3Guppy - You had him taped early. Walter Mitty reincarnated, or maybe his wingman.
You're flying a helicopter, now? You were a fixed wing captain with 10,000 hours and seven type ratings, flying a citation, and had just been rejected by Alaska airlines when you posted as ssg and then as Trickle451...both of your former identities which have recently been banned.
Now you're a helicopter pilot. Who'd have guessed?
Now you're a helicopter pilot. Who'd have guessed?
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confusion
Angels 60, i think you're getting alittle bit confused. A rolling tendancy will occur due to retreating blade stall, which will be one of the criteria taken into consideration when determining a helicopters VNE. Retreating blade stall will occur as the speed of the helicopter increases to the point at which the flapping down of the retreating blade has increased the angle of attack of the retreating blade to it's stalling angle. As soon as any airflow occurs over the rotor disc there will be a difference in the airspeed between the advancing and retreating blades. This will lead to dissymetry of lift, which will be partially compensated for by blade flappping. This will allow safe flight within the flight manual speed parameters. The pilot may have to sit in a specified seat due to C of G considerations, but he certainly won't be required to compensate for a rolling tendancy due to aerodynamic instability in the cruise! If he has to do that, i suggest he find a different helicopter to fly - ie one that has been certified!!
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I really wish I'd found this thread before my Cat renewal. It wouldn't have gone any better but at least the P of F would have got a laugh.
Sven.
Sven.
Avoid imitations
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These theories probably come from a very good source.
Such as this one:
http://www.easyontheeye.net/ladybird/60s/606b/606b.htm
Or they might just be a collection of alternative answers given by the thickest student on the course (a role often played by a crafty CFS trapper).
Such as this one:
http://www.easyontheeye.net/ladybird/60s/606b/606b.htm
Or they might just be a collection of alternative answers given by the thickest student on the course (a role often played by a crafty CFS trapper).