Ditching a helicopter: (incl pictures)
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Hi there - Just wanted to be post 100 and ask one thing .........
Who's talking about ditching now? or is it just something that rhymes with it ........?
energy driven eccentric nirvana
Who's talking about ditching now? or is it just something that rhymes with it ........?
energy driven eccentric nirvana
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Dave, not leaving you out, just didn't get your post before I started mine.
If you can email those articles on the ABC, I'd really appreciate it. If they're not on the computer yet, just point me in the right direction.
Problem with your massless rotor is if you attempt to fly it to position, you will apply a force to the blade. A force applied to massless matter (not possible, but I'll follow it through) will cause infinite acceleration, and your attempt to fly to position will result in catastrophic failure.
Matthew.
If you can email those articles on the ABC, I'd really appreciate it. If they're not on the computer yet, just point me in the right direction.
Problem with your massless rotor is if you attempt to fly it to position, you will apply a force to the blade. A force applied to massless matter (not possible, but I'll follow it through) will cause infinite acceleration, and your attempt to fly to position will result in catastrophic failure.
Matthew.
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heedm,
The lock number that kirilian posted is the term that describes the relationship between the flapping inertia of the blade and the aerodynamic damping it gets (the force feedback) as it flaps. This lock number gives us a feel for the flapping frequency of the rotor blade, which tells us how much we must lead the desired motion to get the proper output. While Lu does not know of any helicopter that has a 90 degree swashplate angle, that is because he gets all wrapped up in how long the pitch arm is (in degrees of rotation) so he gets fouled up in the math. Let's face it, if the pitch horn from the blade was long enough to wrap around the swashplate two times, it would have a 720 degree lead or lag, and that would get that someone's panties in a bunch. Really, the issue is how much ahead of time does the pitch change need to reach the blade to get the blade to hit peak flapping when we want it to. The lighter the blade, and the skinnier it is, with the flattest lift curve slope, the easier it jumps up into position, and the less we have to lead the controls (rig them earlier). The heavier the blade, and the fatter it is (so the air above it slows down its attempt to flap up) and the steeper its lift curve slope, the more we must telegraph the control input to get the disk to obey. While this is all really not purely gyroscopic precession, it is physics (and Dave Jackson, I'll take your advice here anytime!).
We in the industry tell everyone it is gyroscopic precession to keep the troops in line and fool them, but it really is the phase angle between the forcing function (the controls) and the rotor flapping resonance (the disk tilt).
The phase angle for the S-76 is about 56 degrees, which would make Newton roll over in his grave, gyroscopically. Most helos would not be rigged (yes, Lu, rigged, rigged rigged, get used to it) at 90 degrees if we tried to perfect their controls, but pilots are wonderfully adaptive fellows, and quickly get the phase angle just right even if the manufacturer did not. The Benson and De Cierva gyrocopters are examples, where the cyclic stick is directly attached to the swashplate, so pushing forward stick achieves something approximating a left roll, I think (any gyrocopter pilots here to help me out?). Ouch, but it works.
This is similar to a motorcycle, where the way to turn left at speed is to tweek the handlebars rightward, and cause the bike to lean left to make the banked turn. Not natural, but easily learned and quickly second nature.
[ 23 November 2001: Message edited by: Nick Lappos ]
The lock number that kirilian posted is the term that describes the relationship between the flapping inertia of the blade and the aerodynamic damping it gets (the force feedback) as it flaps. This lock number gives us a feel for the flapping frequency of the rotor blade, which tells us how much we must lead the desired motion to get the proper output. While Lu does not know of any helicopter that has a 90 degree swashplate angle, that is because he gets all wrapped up in how long the pitch arm is (in degrees of rotation) so he gets fouled up in the math. Let's face it, if the pitch horn from the blade was long enough to wrap around the swashplate two times, it would have a 720 degree lead or lag, and that would get that someone's panties in a bunch. Really, the issue is how much ahead of time does the pitch change need to reach the blade to get the blade to hit peak flapping when we want it to. The lighter the blade, and the skinnier it is, with the flattest lift curve slope, the easier it jumps up into position, and the less we have to lead the controls (rig them earlier). The heavier the blade, and the fatter it is (so the air above it slows down its attempt to flap up) and the steeper its lift curve slope, the more we must telegraph the control input to get the disk to obey. While this is all really not purely gyroscopic precession, it is physics (and Dave Jackson, I'll take your advice here anytime!).
We in the industry tell everyone it is gyroscopic precession to keep the troops in line and fool them, but it really is the phase angle between the forcing function (the controls) and the rotor flapping resonance (the disk tilt).
The phase angle for the S-76 is about 56 degrees, which would make Newton roll over in his grave, gyroscopically. Most helos would not be rigged (yes, Lu, rigged, rigged rigged, get used to it) at 90 degrees if we tried to perfect their controls, but pilots are wonderfully adaptive fellows, and quickly get the phase angle just right even if the manufacturer did not. The Benson and De Cierva gyrocopters are examples, where the cyclic stick is directly attached to the swashplate, so pushing forward stick achieves something approximating a left roll, I think (any gyrocopter pilots here to help me out?). Ouch, but it works.
This is similar to a motorcycle, where the way to turn left at speed is to tweek the handlebars rightward, and cause the bike to lean left to make the banked turn. Not natural, but easily learned and quickly second nature.
[ 23 November 2001: Message edited by: Nick Lappos ]
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Heedm
>'If you can email those articles on the ABC, I'd really appreciate it. If they're not on the computer yet, just point me in the right direction."<
Xeroxes of these articles were obtained from the American Helicopter Society. A list of the ones I have can been seen on web page: http://www.synchrolite.com/0891.html .
Your E-mail address is not available, so a Private Message has been sent via PPRuNe. If you do not get this message, send me an E-mail at [email protected]
>'A force applied to massless matter (not possible, but I'll follow it through) will cause infinite acceleration, ...."<
The blade is being flown to position in air. If the ascending flap velocity were to exceed the commanded rate, the angle of attack will move to above the blade and force it back down.
_________
Don't want to take words out of Kyrilian's mouth, but to save time;
Lower case gamma is Blade Lock Number.
Upper case Gamma is what Nick is refering to. I think the symbol Delta-psi is also used.
[ 24 November 2001: Message edited by: Dave Jackson ]
[ 25 November 2001: Message edited by: Dave Jackson ]
>'If you can email those articles on the ABC, I'd really appreciate it. If they're not on the computer yet, just point me in the right direction."<
Xeroxes of these articles were obtained from the American Helicopter Society. A list of the ones I have can been seen on web page: http://www.synchrolite.com/0891.html .
Your E-mail address is not available, so a Private Message has been sent via PPRuNe. If you do not get this message, send me an E-mail at [email protected]
>'A force applied to massless matter (not possible, but I'll follow it through) will cause infinite acceleration, ...."<
The blade is being flown to position in air. If the ascending flap velocity were to exceed the commanded rate, the angle of attack will move to above the blade and force it back down.
_________
Don't want to take words out of Kyrilian's mouth, but to save time;
Lower case gamma is Blade Lock Number.
Upper case Gamma is what Nick is refering to. I think the symbol Delta-psi is also used.
[ 24 November 2001: Message edited by: Dave Jackson ]
[ 25 November 2001: Message edited by: Dave Jackson ]
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Lu,
If your concept of understanding still dictates that rotors behave the way they do due to gyroscopic precession, tell me what would happen to a four bladed rotor rigged with a swashplate in a total vacuum, with cyclic and collective inputs. Im interested to hear your response.
If your concept of understanding still dictates that rotors behave the way they do due to gyroscopic precession, tell me what would happen to a four bladed rotor rigged with a swashplate in a total vacuum, with cyclic and collective inputs. Im interested to hear your response.
Iconoclast
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To: Sling Load
Most likely nothing. There would be no response to collective input nor, would there be any response to cyclic input. Whether you believe in aerodynamic precession or, gyroscopic precession in order to make either work you need to be in a field of air. You already know how blades move if you subscribe to aerodynamic precession well if you subscribe to gyroscopic precession you need a differential of lift which creates a nutating force on the rotor system which has the characteristics of a gyroscope rotor. With the differential of lift being greater on the left side (American design) then the force differential will cause the disc to dip over the nose and raise over the tail with forward cyclic.
Now, I’ll give you a question. Please explain aerodynamic precession in the case of retreating blade stall. If the retreating blade stalls and falls due to the lack of lift what makes the advancing blade and therefore the entire disc raise over the nose? I say the entire disc is effected by the extreme difference in lift across the disc and the disc responds due to gyroscopic precession. What do you say?
Most likely nothing. There would be no response to collective input nor, would there be any response to cyclic input. Whether you believe in aerodynamic precession or, gyroscopic precession in order to make either work you need to be in a field of air. You already know how blades move if you subscribe to aerodynamic precession well if you subscribe to gyroscopic precession you need a differential of lift which creates a nutating force on the rotor system which has the characteristics of a gyroscope rotor. With the differential of lift being greater on the left side (American design) then the force differential will cause the disc to dip over the nose and raise over the tail with forward cyclic.
Now, I’ll give you a question. Please explain aerodynamic precession in the case of retreating blade stall. If the retreating blade stalls and falls due to the lack of lift what makes the advancing blade and therefore the entire disc raise over the nose? I say the entire disc is effected by the extreme difference in lift across the disc and the disc responds due to gyroscopic precession. What do you say?
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Lu,
“There would be no response to collective input nor, would there be any response to cyclic input“
I really would expect a reliability engineer to look at the problem in depth not just fire off a line off the top of the head. As you couldn’t be bothered to think it though let me.
In a vacuum the aerodynamic forces will be non-existent, however there are forces that could change the state of the system, namely, friction in the various hinges. A control input pushing upwards would be opposed by friction in the feathering hinge - in the case of elastomeric or other rigid systems this resistance could be significant. The movement of the control orbit can therefore move the blade. As the blade experienced a displacing force and there are no aerodynamic forces damping forces one could expect precession. The magnitude of the forces involved would be very small therefore the response of the disk would be very slow. Interestingly, as there are no aerodynamic damping forces the disk could well overshoot it’s commanded position, although in an articulated head with a hinge offset a damping force will still be created as a result of the cyclic flapping of blades through the plane of rotation. In the case of a collective input one could expect momentary coning would occur before the disk slowly resumes an un-coned state due to inertial effects.
In summary, in a vacuum one can expect some sort of disk response to cyclic inputs but only momentary movement in response to collective input.
GA
“There would be no response to collective input nor, would there be any response to cyclic input“
I really would expect a reliability engineer to look at the problem in depth not just fire off a line off the top of the head. As you couldn’t be bothered to think it though let me.
In a vacuum the aerodynamic forces will be non-existent, however there are forces that could change the state of the system, namely, friction in the various hinges. A control input pushing upwards would be opposed by friction in the feathering hinge - in the case of elastomeric or other rigid systems this resistance could be significant. The movement of the control orbit can therefore move the blade. As the blade experienced a displacing force and there are no aerodynamic forces damping forces one could expect precession. The magnitude of the forces involved would be very small therefore the response of the disk would be very slow. Interestingly, as there are no aerodynamic damping forces the disk could well overshoot it’s commanded position, although in an articulated head with a hinge offset a damping force will still be created as a result of the cyclic flapping of blades through the plane of rotation. In the case of a collective input one could expect momentary coning would occur before the disk slowly resumes an un-coned state due to inertial effects.
In summary, in a vacuum one can expect some sort of disk response to cyclic inputs but only momentary movement in response to collective input.
GA
Iconoclast
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To: Grey Area
It would be sneaky of me to say that if Sling Load indicated that we were in a vacuum situation that I would assume a frictionless environment but I didn’t think of that. Based on what you have stated in your post you are indicating that the blades would move not by aerodynamic forces due to the lack of air but solely due to gyroscopic precession. Did I get your statement correctly? If that is what you indicated then upon your return to Jolly Old you will be taken directly to the tower and summarily beheaded.
Down with aerodynamics and, up with physics.
It would be sneaky of me to say that if Sling Load indicated that we were in a vacuum situation that I would assume a frictionless environment but I didn’t think of that. Based on what you have stated in your post you are indicating that the blades would move not by aerodynamic forces due to the lack of air but solely due to gyroscopic precession. Did I get your statement correctly? If that is what you indicated then upon your return to Jolly Old you will be taken directly to the tower and summarily beheaded.
Down with aerodynamics and, up with physics.
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Stick forward: max +ve rate of pitch change at front, opposed by moment of intertia about longditudinal axis, resulting in and upward flapping tendancy during a blades' passage through the front half of the disc. So it would reach a high point on port side (hide behind the term Gyroscopic Precession if you like). The forward stick displacement would require an accompanying stick force to the right.(the force you need to be continuously increasing pitch at the front).
The new resulting plane of rotation would set up a differance from the control plane equivalent to pushing the stick to the left ..... and around and around the problem would proceed
(this is just a lite look at one aspect)
The new resulting plane of rotation would set up a differance from the control plane equivalent to pushing the stick to the left ..... and around and around the problem would proceed
(this is just a lite look at one aspect)
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It's Lu's presence which does this.
Educating Lu is drain on the pilots.
Whatch out Lu's 'stick time' is increasing all the time. He's almost a pilot now.
Appology in advance to thread owner...
Educating Lu is drain on the pilots.
Whatch out Lu's 'stick time' is increasing all the time. He's almost a pilot now.
Appology in advance to thread owner...
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Lu,
I wouldn't say the disc drops due to gyroscopic precession, there is a difference in lift between the retreating stalling blade and the still advancing blade, which at high speeds is approaching compressibility and the problems that brings. At that condition, lift is not equal across the rotor and our old friend dissymetry of lift comes into effect. In any case, the disc will rise and slow the aircraft down and if the pilot is a total idiot and pushes cylic forward without changing collective ,the condition will worsen and roll.
Im not an engineer Lu, only a student of the subject, but I admit when Im hooped on something and don't understand it.
Grey Area even saw that.Mechanical linkages work in vacuums too Lu.
The point of the vacuum was to remove the affect of aerodynamics from the rotor,
if you beleive that a rotor works like a gyroscope, then aerodynamics play a minor role in rotor behaviour, is that what you understand?
[ 24 November 2001: Message edited by: sling load ]
I wouldn't say the disc drops due to gyroscopic precession, there is a difference in lift between the retreating stalling blade and the still advancing blade, which at high speeds is approaching compressibility and the problems that brings. At that condition, lift is not equal across the rotor and our old friend dissymetry of lift comes into effect. In any case, the disc will rise and slow the aircraft down and if the pilot is a total idiot and pushes cylic forward without changing collective ,the condition will worsen and roll.
Im not an engineer Lu, only a student of the subject, but I admit when Im hooped on something and don't understand it.
Grey Area even saw that.Mechanical linkages work in vacuums too Lu.
The point of the vacuum was to remove the affect of aerodynamics from the rotor,
if you beleive that a rotor works like a gyroscope, then aerodynamics play a minor role in rotor behaviour, is that what you understand?
[ 24 November 2001: Message edited by: sling load ]
Iconoclast
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To: Sling Load
“I wouldn't say the disc drops due to gyroscopic precession, there is a difference in lift between the retreating stalling blade and the still advancing blade, which at high speeds is approaching compressibility and the problems that brings. At that condition, lift is not equal across the rotor and our old friend dissymetry of lift comes into effect. In any case, the disc will rise and slow the aircraft down and if the pilot is a total idiot and pushes cyclic forward without changing collective, the condition will worsen and roll”.
First of all, let’s disregard compressibility as retreating blade stall can occur under several different sets of conditions. I agree that there will be a lift differential. At this point our opinions start to differ. The roll will occur prior to the disc rising over the nose. At the onset of retreating blade stall there is a pronounced vibration followed by a roll to the left (American design). If at this time the pilot has not taken corrective action the disc will not just rise over the nose it will flap (blow) back quite violently and in some cases the blades will contact the tail boom (cone).
The major difference between us is how we view the reasons for roll and blow (flap) back. You say that is a pure aerodynamic response and I agree that aerodynamics is involved. As I have stated previously this is an alternate to gyroscopic theory and I can accept that. However, I believe that the differential of lift or, differential of forces acting on the disc which has gyroscopic characteristics causing it to precess. The roll is aerodynamic but it is the precursor to the flap back, which I believe is the result of gyroscopic precession.
The same condition exists but to a lesser degree when transitioning and the helicopter rolls and the disc blows back. Under these conditions the pilot can take corrective action by applying forward cyclic.
“I wouldn't say the disc drops due to gyroscopic precession, there is a difference in lift between the retreating stalling blade and the still advancing blade, which at high speeds is approaching compressibility and the problems that brings. At that condition, lift is not equal across the rotor and our old friend dissymetry of lift comes into effect. In any case, the disc will rise and slow the aircraft down and if the pilot is a total idiot and pushes cyclic forward without changing collective, the condition will worsen and roll”.
First of all, let’s disregard compressibility as retreating blade stall can occur under several different sets of conditions. I agree that there will be a lift differential. At this point our opinions start to differ. The roll will occur prior to the disc rising over the nose. At the onset of retreating blade stall there is a pronounced vibration followed by a roll to the left (American design). If at this time the pilot has not taken corrective action the disc will not just rise over the nose it will flap (blow) back quite violently and in some cases the blades will contact the tail boom (cone).
The major difference between us is how we view the reasons for roll and blow (flap) back. You say that is a pure aerodynamic response and I agree that aerodynamics is involved. As I have stated previously this is an alternate to gyroscopic theory and I can accept that. However, I believe that the differential of lift or, differential of forces acting on the disc which has gyroscopic characteristics causing it to precess. The roll is aerodynamic but it is the precursor to the flap back, which I believe is the result of gyroscopic precession.
The same condition exists but to a lesser degree when transitioning and the helicopter rolls and the disc blows back. Under these conditions the pilot can take corrective action by applying forward cyclic.
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Lu,
YOU HAVE GONE TOO FAR! Friendly banter is one thing you have just crossed the line!
Your last post was DANGEROUSLY ill advised, there is no similarity between retreating blade stall and transition at all. Your comment could lead to confusion and God forbid someone continuing to advance the cyclic in an incipient retreating blade stall, YOUR ADVICE WILL KILL THEM!! As someone who has taught recovery from incipient RBS and has had the misfortune to lose control (and luckily regain) as a result of RBS I can categorically say you are talking out of your backside.
PLEASE FIND OUT WHAT YOU ARE TALKING ABOUT, YOU ARE BECOMING A FLIGHT SAFETY HAZARD!
This is not a point for discussion Lou.
GA
YOU HAVE GONE TOO FAR! Friendly banter is one thing you have just crossed the line!
Your last post was DANGEROUSLY ill advised, there is no similarity between retreating blade stall and transition at all. Your comment could lead to confusion and God forbid someone continuing to advance the cyclic in an incipient retreating blade stall, YOUR ADVICE WILL KILL THEM!! As someone who has taught recovery from incipient RBS and has had the misfortune to lose control (and luckily regain) as a result of RBS I can categorically say you are talking out of your backside.
PLEASE FIND OUT WHAT YOU ARE TALKING ABOUT, YOU ARE BECOMING A FLIGHT SAFETY HAZARD!
This is not a point for discussion Lou.
GA
Iconoclast
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To: Grey Area
You missed the point of the comparison. In order to accept my reasoning you have to accept the theory of gyroscopic precession. If you can’t accept that, then substitute aerodynamic precession.
Transverse flow effect:
When the helicopter is in the area of transverse flow effect two things happen. One is the helicopter will roll to the right and the rotor will blow back. These actions are relatively benign and the pilot can correct for these effects by input of cyclic control. The blowback is caused by a differential of lift across the disc with the greater lift being on the right side. This lift differential will in effect be a perturbing force on the rotor (which has gyroscopic characteristics) and cause the disc to tilt up over the nose and down over the tail. This disc movement if I understand it correctly in effect changes the angle of attack on the blades and the disc responds by tilting to the right.
Passage through the transverse flow field will cause the helicopter to vibrate just below effective translational lift. This effect can also occur during landing when the helicopter passes through the effective translational lift.
Retreating blade stall:
In retreating blade stall the retreating blade(s) are generating less lift than the advancing blade(s).
This lift differential is a perturbing force on the right side of the disc and is acting upward causing the disc to respond as a gyro rotor and the resultant of this upward force is the tilting of the disc up over the nose and down over the tail. The differential of lift will cause the helicopter to roll to the left, which is a precursor to the flapping back or blowing back. In this area there is a pronounced vibration just prior to the blow / flap back.
In both cases there is a differential of lift causing the disc to tilt up over the nose and down over the tail. In one case, the helicopter rolls right and in the other the helicopter rolls left. The roll is the result of aerodynamic forces while the flapback / blowback is the function of lift differential across the disc and the upward perturbing force results in a gyroscopic response.
In the case of the actions resulting from transverse flow effect the movement of the helicopter and the rotor is benign and the pilot can counter these actions with cyclic input. In the case of retreating blade stall the roll is pronounced and there is a lot of vibration. If by that time the pilot has not taken corrective action the disc will flapback violently and most likely chop off the tail boom.
Hopefully you can see that the actions taking place are similar if not identical. The corrective actions by the pilot are different and there is a major difference in what happens to the rotor relative to its’ response. Each condition should be taught in the flight training program and it should be obvious to any pilot that he / she will not experience retreating blade stall at translational lift speeds and therefore, understand the corrective actions that must be undertaken for both situations.
You missed the point of the comparison. In order to accept my reasoning you have to accept the theory of gyroscopic precession. If you can’t accept that, then substitute aerodynamic precession.
Transverse flow effect:
When the helicopter is in the area of transverse flow effect two things happen. One is the helicopter will roll to the right and the rotor will blow back. These actions are relatively benign and the pilot can correct for these effects by input of cyclic control. The blowback is caused by a differential of lift across the disc with the greater lift being on the right side. This lift differential will in effect be a perturbing force on the rotor (which has gyroscopic characteristics) and cause the disc to tilt up over the nose and down over the tail. This disc movement if I understand it correctly in effect changes the angle of attack on the blades and the disc responds by tilting to the right.
Passage through the transverse flow field will cause the helicopter to vibrate just below effective translational lift. This effect can also occur during landing when the helicopter passes through the effective translational lift.
Retreating blade stall:
In retreating blade stall the retreating blade(s) are generating less lift than the advancing blade(s).
This lift differential is a perturbing force on the right side of the disc and is acting upward causing the disc to respond as a gyro rotor and the resultant of this upward force is the tilting of the disc up over the nose and down over the tail. The differential of lift will cause the helicopter to roll to the left, which is a precursor to the flapping back or blowing back. In this area there is a pronounced vibration just prior to the blow / flap back.
In both cases there is a differential of lift causing the disc to tilt up over the nose and down over the tail. In one case, the helicopter rolls right and in the other the helicopter rolls left. The roll is the result of aerodynamic forces while the flapback / blowback is the function of lift differential across the disc and the upward perturbing force results in a gyroscopic response.
In the case of the actions resulting from transverse flow effect the movement of the helicopter and the rotor is benign and the pilot can counter these actions with cyclic input. In the case of retreating blade stall the roll is pronounced and there is a lot of vibration. If by that time the pilot has not taken corrective action the disc will flapback violently and most likely chop off the tail boom.
Hopefully you can see that the actions taking place are similar if not identical. The corrective actions by the pilot are different and there is a major difference in what happens to the rotor relative to its’ response. Each condition should be taught in the flight training program and it should be obvious to any pilot that he / she will not experience retreating blade stall at translational lift speeds and therefore, understand the corrective actions that must be undertaken for both situations.
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Lu,
All the major Test Flying Schools (ETPS, USNTPS, EPNER), Eurocopter, AugustaWestland etc plus the major text books, Gessow, Prouty et al disagree with you, so do I.
All the major Test Flying Schools (ETPS, USNTPS, EPNER), Eurocopter, AugustaWestland etc plus the major text books, Gessow, Prouty et al disagree with you, so do I.
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Lu
What about Grey Area's more important point?
Professional pilots/instructors are able to make their own asessments of the value or otherwise of your theories, but the site also has lots of inexperienced/low time pilots.
Since you often give your views on how a pilot should react in a particular emergency/problem, don't you think you should point out you are not a pilot?
Perhaps you could add a 'health warning' to your 'Cat' signature?
I mean this as serious suggestion in the interests of flight safety.
What about Grey Area's more important point?
Professional pilots/instructors are able to make their own asessments of the value or otherwise of your theories, but the site also has lots of inexperienced/low time pilots.
Since you often give your views on how a pilot should react in a particular emergency/problem, don't you think you should point out you are not a pilot?
Perhaps you could add a 'health warning' to your 'Cat' signature?
I mean this as serious suggestion in the interests of flight safety.
Iconoclast
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To: Hoverman
“What about Grey Area's more important point?
Professional pilots/instructors are able to make their own assessments of the value or otherwise of your theories, but the site also has lots of inexperienced/low time pilots.
Since you often give your views on how a pilot should react in a particular emergency/problem, don't you think you should point out you are not a pilot?
Perhaps you could add a 'health warning' to your 'Cat' signature?
I mean this as serious suggestion in the interests of flight safety”.
To my knowledge the only “ADVICE’ I have offered relative to the recovery from an emergency situation was the recovery from a zero G incident and those instructions were quoted from the Robinson POH for the R-22 and the R-44. Regarding those instructions I added that “IF” there is in effect an 18-degree offset when the pilot followed the POH instructions he could possibly add to the right roll developed by the tail rotor during the zero G incident which is counter to the POH instructions. It seems that there is a degree of “confusion” between some Robinson instructors as to exactly how the cyclic is to be handled during zero G recovery.
Regarding the 18-degree offset I have Contacted Canadian Helicopters in Ontario and they are considering my request to perform the test. Once the test is performed we will know who is right regarding this condition.
Regarding my not being a pilot all the reader of any of my posts has to do is read my Bio. It will indicate that I have no ratings. Nor does it indicate what type of helicopters I fly. If you read some other posts you will see that some individuals address some really intricate problems relative to helicopter aerodynamics and they are not pilots.
Here is another point regarding the supposed 18-degrree offset. It is not dangerous and the pilot can if it exists correct for it with cyclic input. The only place where it would be dangerous is in recovery from a zero G incident and then it would only be dangerous for an inexperienced pilot.
“What about Grey Area's more important point?
Professional pilots/instructors are able to make their own assessments of the value or otherwise of your theories, but the site also has lots of inexperienced/low time pilots.
Since you often give your views on how a pilot should react in a particular emergency/problem, don't you think you should point out you are not a pilot?
Perhaps you could add a 'health warning' to your 'Cat' signature?
I mean this as serious suggestion in the interests of flight safety”.
To my knowledge the only “ADVICE’ I have offered relative to the recovery from an emergency situation was the recovery from a zero G incident and those instructions were quoted from the Robinson POH for the R-22 and the R-44. Regarding those instructions I added that “IF” there is in effect an 18-degree offset when the pilot followed the POH instructions he could possibly add to the right roll developed by the tail rotor during the zero G incident which is counter to the POH instructions. It seems that there is a degree of “confusion” between some Robinson instructors as to exactly how the cyclic is to be handled during zero G recovery.
Regarding the 18-degree offset I have Contacted Canadian Helicopters in Ontario and they are considering my request to perform the test. Once the test is performed we will know who is right regarding this condition.
Regarding my not being a pilot all the reader of any of my posts has to do is read my Bio. It will indicate that I have no ratings. Nor does it indicate what type of helicopters I fly. If you read some other posts you will see that some individuals address some really intricate problems relative to helicopter aerodynamics and they are not pilots.
Here is another point regarding the supposed 18-degrree offset. It is not dangerous and the pilot can if it exists correct for it with cyclic input. The only place where it would be dangerous is in recovery from a zero G incident and then it would only be dangerous for an inexperienced pilot.