R22 Corner
Joined: Nov 2000
Posts: 467
Likes: 0
From: Sunrise, Fl. U.S.A.
Yep, for use in left turns.
Now, what I'd like to see is a small strap over the left door, for pax to hold onto, some have nothing to place their hands on when flying except the windowsill, so to speak.
Cars have 'em, why not a Robbie? (I know, the loads would have to be considered.
How much pull could a pax pull if a pax did pull in a panic?
)
Now, what I'd like to see is a small strap over the left door, for pax to hold onto, some have nothing to place their hands on when flying except the windowsill, so to speak.
Cars have 'em, why not a Robbie? (I know, the loads would have to be considered.
How much pull could a pax pull if a pax did pull in a panic?
)
Joined: Mar 2002
Posts: 489
Likes: 2
From: UK
Coning Hinges
Dave & Lu,
In my opinion the Robinson hub is a small work of genius! [Here we go....]
Consider a standard Bell type semi-rigid teetering rotor as used on the JetRanger. As the rotor is loaded (as the collective is raised) the blades will bend upwards elastically since there is no coning hinge to allow the CF and Aero forces to find a natural equilibrium.
Since the blade has now been bent above the pitch change bearing axis (radial from hub) the drag forces on the blade can actually create an additional moment about the pitch change axis which will be dependent on azimuth position and flight regime.
Which in English means.....very large and fatigue inducing oscillating control loads - STICK SHAKE.
By adding a coning hinge, the hub cannot resist a bending moment at the blade root because its free to move, therefore, providing the pitch change bearing is outboard of the coning hinge - as it is, then the blade fundamental bending mode (curving upwards) is largely eliminated as is stick shake. Of coarse the higher harmonics are still present but the advantages in stick shake reduction are significant.
If you would like a further explanation of this have a look at dear Mr. Robinson's patent application on the US Patent site (do a search for tri-hinge rotor system)
In summary, without the coning hinges, we would have a cyclic that jumped around so much that helicopter pilots the world over would be suffering with 'vibration white finger'! Not to mention that blades would probabley have to be strengthened, and wouldn't last as long.
Hope this helps
CRAN
In my opinion the Robinson hub is a small work of genius! [Here we go....]
Consider a standard Bell type semi-rigid teetering rotor as used on the JetRanger. As the rotor is loaded (as the collective is raised) the blades will bend upwards elastically since there is no coning hinge to allow the CF and Aero forces to find a natural equilibrium.
Since the blade has now been bent above the pitch change bearing axis (radial from hub) the drag forces on the blade can actually create an additional moment about the pitch change axis which will be dependent on azimuth position and flight regime.
Which in English means.....very large and fatigue inducing oscillating control loads - STICK SHAKE.
By adding a coning hinge, the hub cannot resist a bending moment at the blade root because its free to move, therefore, providing the pitch change bearing is outboard of the coning hinge - as it is, then the blade fundamental bending mode (curving upwards) is largely eliminated as is stick shake. Of coarse the higher harmonics are still present but the advantages in stick shake reduction are significant.
If you would like a further explanation of this have a look at dear Mr. Robinson's patent application on the US Patent site (do a search for tri-hinge rotor system)
In summary, without the coning hinges, we would have a cyclic that jumped around so much that helicopter pilots the world over would be suffering with 'vibration white finger'! Not to mention that blades would probabley have to be strengthened, and wouldn't last as long.
Hope this helps
CRAN
Joined: Nov 2000
Posts: 452
Likes: 0
From: Vancouver, BC, Canada
CRAN,
IMHO. Yes & No
For the pleasure of a theoretical discussion;-
I believe that all, or most, teetering rotors have a fixed pre-cone angle in their hubs. This pre-cone angle is around 2-3 degrees, and is probably close to the dynamic coning angle of the rotor disk, when hovering at gross weight. Variations in rotor loading will, of course, increase or decrease the actual dynamic coning angle above and below that of the pre-cone angle.
I agree that additional vibration &/or cross-coupling activity may take place when a blade's centers of lift, percussion, drag, and mass etc. are not inline with the feathering bearing axis. It must be remembered though, that even if a blade's 'centers' are aligned with the feathering axis, there will always be misalignments between the 'centers' of the two blades and the teetering hinge.
I have felt that if Robinson wanted the two outside hinges to be only coning hinges, and to not be subjected to independent blade flapping, he should have mechanically linked the two hinges together, so that they rotated in unison.
Again IMHO, the advantage that you mention may very well be true, but I suspect that the 'sloppiness' of hub, due to the three hinges, MAY be the source of other difficulties.
IMHO. Yes & No
For the pleasure of a theoretical discussion;-
I believe that all, or most, teetering rotors have a fixed pre-cone angle in their hubs. This pre-cone angle is around 2-3 degrees, and is probably close to the dynamic coning angle of the rotor disk, when hovering at gross weight. Variations in rotor loading will, of course, increase or decrease the actual dynamic coning angle above and below that of the pre-cone angle.
I agree that additional vibration &/or cross-coupling activity may take place when a blade's centers of lift, percussion, drag, and mass etc. are not inline with the feathering bearing axis. It must be remembered though, that even if a blade's 'centers' are aligned with the feathering axis, there will always be misalignments between the 'centers' of the two blades and the teetering hinge.
I have felt that if Robinson wanted the two outside hinges to be only coning hinges, and to not be subjected to independent blade flapping, he should have mechanically linked the two hinges together, so that they rotated in unison.
Again IMHO, the advantage that you mention may very well be true, but I suspect that the 'sloppiness' of hub, due to the three hinges, MAY be the source of other difficulties.
Joined: Nov 2000
Posts: 467
Likes: 0
From: Sunrise, Fl. U.S.A.
Are these cracks developing as a result of excessive spanwise bending caused by leading and lagging of the blades?
However referencing the question posed, possibly. Certainly a contributor.
But I think the other inspection requirement was more for cracks at the root that they determined to be from high flapping and coning due to flights over gross weight, etc. didn't it?
Iconoclast
Joined: Sep 2000
Posts: 2,132
Likes: 0
From: The home of Dudley Dooright-Where the lead dog is the only one that gets a change of scenery.
Chicken and the egg theory.
To: RW-1
I'm surprised that you agreed.
Quote:
"But I think the other inspection requirement was more for cracks at the root that they determined to be from high flapping and coning due to flights over gross weight, etc. didn't it?"
This may be true but for whatever reason the blades coned/flapped it is this action that causes the lead and lag. Higher gross weights can enter into it and make the situation worse by placing the blades under higher stress levels relative to lower gross weights.
I'm surprised that you agreed.
Quote:
"But I think the other inspection requirement was more for cracks at the root that they determined to be from high flapping and coning due to flights over gross weight, etc. didn't it?"
This may be true but for whatever reason the blades coned/flapped it is this action that causes the lead and lag. Higher gross weights can enter into it and make the situation worse by placing the blades under higher stress levels relative to lower gross weights.
Joined: Jul 2002
Posts: 3
Likes: 0
From: The World
CRAN - try these
http://geocities.com/worldbeaterheli/letter.GIF
http://geocities.com/worldbeaterheli/AD.gif
After trying this link out, it seems that geocities won't let you access it from a bulletin board, so you have to cut and paste the web address and it works fine
I've also got a couple of pics somewhere, I'll see if I can dig them out
http://geocities.com/worldbeaterheli/letter.GIF
http://geocities.com/worldbeaterheli/AD.gif
After trying this link out, it seems that geocities won't let you access it from a bulletin board, so you have to cut and paste the web address and it works fine
I've also got a couple of pics somewhere, I'll see if I can dig them out
Last edited by Worldbeater; 4th July 2002 at 09:45.
Joined: Apr 2000
Posts: 4
Likes: 0
From: Branchville, NJ USA
Sir:
Me thinks that it is you that missed the whole point of that window.
Although pointless in your opinion, most experienced pilots like to clear airspace into which they are about to fly.
This (in your opinion 'dinky') window, is in fact priceless when your solo right seat pilot is turning left.
Army pilots were taught to verbally call out before turning: "Clear left, and above"
The pointless dinky window also is very helpful flying standard left hand traffic patterns.
Frank Robinson does very few "pointless" things.
Low time pilots do many.
Me thinks that it is you that missed the whole point of that window.
Although pointless in your opinion, most experienced pilots like to clear airspace into which they are about to fly.
This (in your opinion 'dinky') window, is in fact priceless when your solo right seat pilot is turning left.
Army pilots were taught to verbally call out before turning: "Clear left, and above"
The pointless dinky window also is very helpful flying standard left hand traffic patterns.
Frank Robinson does very few "pointless" things.
Low time pilots do many.
Joined: Sep 2000
Posts: 166
Likes: 7
From: states
Here is a link to the patent office data for the rotor head with tri hinges….
Should be good fodder for all the professional and aspiring engineers out there…
http://patft.uspto.gov/netacgi/nph-P...ND+AN/Robinson
Should be good fodder for all the professional and aspiring engineers out there…
http://patft.uspto.gov/netacgi/nph-P...ND+AN/Robinson
Joined: Apr 2002
Posts: 147
Likes: 0
From: Hartford, CT USA
actually I have recently found out that the window is actually a small sunroof for the passenger
By simply standing up extremely quickly and ramming their head through the sunroof they can fully enjoy the downwash and assorted bugs that always seem to get on your mast.
I am sure it has many other uses, but i shall have to think on it more.
By simply standing up extremely quickly and ramming their head through the sunroof they can fully enjoy the downwash and assorted bugs that always seem to get on your mast.
I am sure it has many other uses, but i shall have to think on it more.
Joined: Mar 2002
Posts: 243
Likes: 1
From: West of zero
Some background
As with all these cases, some background knowledge will place the severity of the problem, or lack thereof, in proper perspective. The Safety Alert was issued as result of an R22 crash in Latin America, where one main rotor blade broke off, leading to two fatalities. The crack that caused the blade to break off started at the location mentioned in the Safety Alert, so visual inspections using a 10X magnification were called for.
To the best of my knowledge (and I stand to be corrected) no other cracked blades have been found, and this was the first failure of an R22 M/R blade in flight since shortly after the initial certification. Those early failures (not sure if there were more than one) were traced back to poor quality control on the part of a vendor – so now Robinson manufacture their own rotor blades. When one considers the number of R22s daily being abused by ham-fisted students (not your fault guys and gals, we all started from zero!) this indicates remarkable reliability.
But even the most reliable design can only take so much abuse. What the Safety Alert didn’t include were the descriptions by witnesses of the “macho” attitude displayed by the victims, the owners of the helicopter, towards the limitations published in the Pilot’s Operating Handbook. Allegedly, they consistently flew this aircraft well over max gross weight, well over Vne, and well over manifold pressure limits (overtorqued). What their preflight inspections were like can be left to the imagination. Treat any helicopter like that, and you (or what’s left of you) will shortly be sitting in a nasty mess. Ignoring clear warnings that all is not well like the rotor rapidly going out of balance for no known reason is just another way to arrive at a sticky end.
I really don’t like airing dirty laundry like this (“de mortis nil quam bonus”, etc.). But I also don’t like the way some people will point to ANY mishap with a certain machine as proof positive that the designer is an incompetent nincompoop at best, a homicidal maniac at worst, and Robinsons seem to attract more than their fair share of this kind of mud-slinging. Two people ignored the advice the designers and testers of a machine gave them, and consequently removed themselves from the human gene pool. That they did so in a Robinson helicopter is incidental.
So, why did Robinson publish a Safety Alert/Notice as result of this flouting of the rules? Well, the fact that Robinson is headquartered in Southern California, tort lawsuit capital of the world, may have something to do with that. The R22 POH also carries a Safety Notice about the hazards posed by powerlines – hard to imagine which design deficiency that’s supposed to cover up.
To the best of my knowledge (and I stand to be corrected) no other cracked blades have been found, and this was the first failure of an R22 M/R blade in flight since shortly after the initial certification. Those early failures (not sure if there were more than one) were traced back to poor quality control on the part of a vendor – so now Robinson manufacture their own rotor blades. When one considers the number of R22s daily being abused by ham-fisted students (not your fault guys and gals, we all started from zero!) this indicates remarkable reliability.
But even the most reliable design can only take so much abuse. What the Safety Alert didn’t include were the descriptions by witnesses of the “macho” attitude displayed by the victims, the owners of the helicopter, towards the limitations published in the Pilot’s Operating Handbook. Allegedly, they consistently flew this aircraft well over max gross weight, well over Vne, and well over manifold pressure limits (overtorqued). What their preflight inspections were like can be left to the imagination. Treat any helicopter like that, and you (or what’s left of you) will shortly be sitting in a nasty mess. Ignoring clear warnings that all is not well like the rotor rapidly going out of balance for no known reason is just another way to arrive at a sticky end.
I really don’t like airing dirty laundry like this (“de mortis nil quam bonus”, etc.). But I also don’t like the way some people will point to ANY mishap with a certain machine as proof positive that the designer is an incompetent nincompoop at best, a homicidal maniac at worst, and Robinsons seem to attract more than their fair share of this kind of mud-slinging. Two people ignored the advice the designers and testers of a machine gave them, and consequently removed themselves from the human gene pool. That they did so in a Robinson helicopter is incidental.
So, why did Robinson publish a Safety Alert/Notice as result of this flouting of the rules? Well, the fact that Robinson is headquartered in Southern California, tort lawsuit capital of the world, may have something to do with that. The R22 POH also carries a Safety Notice about the hazards posed by powerlines – hard to imagine which design deficiency that’s supposed to cover up.
Joined: Nov 2000
Posts: 2,018
Likes: 73
From: Pewsey, UK
Buitenzorg - also some R22 fatals in Australia, caused by main blade separation. I seem to recall that in one instance a contributory factor was the fact that the owner ran the blades over the recommended TBO.
Check the Australian ATSB website for details of at least 2 MRB separations leading to fatalities.
[Edited to include ATSB references]
Check the Australian ATSB website for details of at least 2 MRB separations leading to fatalities.
[Edited to include ATSB references]
Joined: Jul 2002
Posts: 16
Likes: 0
From: Cheshire
just a quick one about the robbo blades cracking,
as a flight instructor i see how people treat the poor little R22 on a daily basis, the 206's and R44's dont get it as much (probably due to cost)and it is obviously my job to educate people.
the pictures i saw were of a lovely long crack (about 2-3")around the round part of the blade root (with the feathering spindle inside) starting at the leading edge.
the pilot said he had alarge vibration from the start of his flight that got worse, not surprising! when will people learn to do a THOROUGH 'A' check?
All i can say to all those who dis franks designs is that in 2500 hours instruction on the R22 (and plenty on R44 too) i havnt had a problem - rear the poh and abide by it and you wont have a problem
as a flight instructor i see how people treat the poor little R22 on a daily basis, the 206's and R44's dont get it as much (probably due to cost)and it is obviously my job to educate people.
the pictures i saw were of a lovely long crack (about 2-3")around the round part of the blade root (with the feathering spindle inside) starting at the leading edge.
the pilot said he had alarge vibration from the start of his flight that got worse, not surprising! when will people learn to do a THOROUGH 'A' check?
All i can say to all those who dis franks designs is that in 2500 hours instruction on the R22 (and plenty on R44 too) i havnt had a problem - rear the poh and abide by it and you wont have a problem
Guest
Posts: n/a
Some comments from the Peanut Gallery:
1) Lu, "Spanwise bending" is not lead-lag. We use the term "flatwise" to describe upward bending in the flapping axis, "torsional to describe the twisting of the blade around its long axis, and "edgewise" to describe bending in the lead-lag direction. Spanwise is the direction where the centripital force (please, lets not go there!) is exerted, there is no "spanwise bending"
2) The main reason why this AD was issued is because when an accident happens, for whatever cause, the lessons learned are spread far and wide to help us all. The cracks in edgewise bending at the root are called the "failure mode" of the blade, or at least one of them. The location, growth rate and symptoms (vibration) are all great knowledge for the grass roots folks to store and use, as this knowledge can help prevent the next accident.
3) Having sat in grave meetings with our experts in review of accidents, I can assure you the designers and managers take very seriously their responsibility. Nobody I know of in this industry has a casual attitude about this stuff. Too often some person pushes the theory that big mistakes are just passed over, professionals rely on bluff and legalisms to avoid facing the truth, and known flaws are just glossed over by uncaring faceless minions who chase the dollar. That couldn't be farther from the truth.
4) Regarding legal coverups, the law specifically absolves a manufacturer who improves a design from using that improvement as proof of a mistake in the first place. This is a piece of wisdom that prevents the legal system from stiffling improvements, and actually impeding safety and progress. As long as the original designer used state of the art practices and dilligence in the original design, improving that design, even for a failure, is not proof of negligence (Flying Lawyer, did I just step on your turf?)
5) I know this is true for the big manufacturers, whose engineers and test pilots I work with regularly. From what I have read and seen of the smaller outfits, I am also sure it fits: We love flying machines, we try to make them as best we can, we test the heck out of them, and we fix them when they need it. Many of the professionals in the design teams are pilots themselves. We pass on the painful lessons we learn, and we pass on the lessons others learn with them. We rely on all the folks who put the machines to use for our livelyhood, our reputations are our foundations. We also respect the trust our customers place in us.
6) Some advice: when you read some poster criticizing a manufacturer, an operator or another pilot, or a regulatory agency, use the facts provided, learn from those facts, but take the evil motive and stupidity comments with a skeptical eye. President Harry Truman put it well in a letter he wrote, while President, to a reviewer who criticized his daughter's piano concert. "Some day I hope to meet you. When that happens you'll need a new nose." Were I Frank Robinson, I'd be looking for a few folks....
1) Lu, "Spanwise bending" is not lead-lag. We use the term "flatwise" to describe upward bending in the flapping axis, "torsional to describe the twisting of the blade around its long axis, and "edgewise" to describe bending in the lead-lag direction. Spanwise is the direction where the centripital force (please, lets not go there!) is exerted, there is no "spanwise bending"
2) The main reason why this AD was issued is because when an accident happens, for whatever cause, the lessons learned are spread far and wide to help us all. The cracks in edgewise bending at the root are called the "failure mode" of the blade, or at least one of them. The location, growth rate and symptoms (vibration) are all great knowledge for the grass roots folks to store and use, as this knowledge can help prevent the next accident.
3) Having sat in grave meetings with our experts in review of accidents, I can assure you the designers and managers take very seriously their responsibility. Nobody I know of in this industry has a casual attitude about this stuff. Too often some person pushes the theory that big mistakes are just passed over, professionals rely on bluff and legalisms to avoid facing the truth, and known flaws are just glossed over by uncaring faceless minions who chase the dollar. That couldn't be farther from the truth.
4) Regarding legal coverups, the law specifically absolves a manufacturer who improves a design from using that improvement as proof of a mistake in the first place. This is a piece of wisdom that prevents the legal system from stiffling improvements, and actually impeding safety and progress. As long as the original designer used state of the art practices and dilligence in the original design, improving that design, even for a failure, is not proof of negligence (Flying Lawyer, did I just step on your turf?)
5) I know this is true for the big manufacturers, whose engineers and test pilots I work with regularly. From what I have read and seen of the smaller outfits, I am also sure it fits: We love flying machines, we try to make them as best we can, we test the heck out of them, and we fix them when they need it. Many of the professionals in the design teams are pilots themselves. We pass on the painful lessons we learn, and we pass on the lessons others learn with them. We rely on all the folks who put the machines to use for our livelyhood, our reputations are our foundations. We also respect the trust our customers place in us.
6) Some advice: when you read some poster criticizing a manufacturer, an operator or another pilot, or a regulatory agency, use the facts provided, learn from those facts, but take the evil motive and stupidity comments with a skeptical eye. President Harry Truman put it well in a letter he wrote, while President, to a reviewer who criticized his daughter's piano concert. "Some day I hope to meet you. When that happens you'll need a new nose." Were I Frank Robinson, I'd be looking for a few folks....
Iconoclast
Joined: Sep 2000
Posts: 2,132
Likes: 0
From: The home of Dudley Dooright-Where the lead dog is the only one that gets a change of scenery.
In response:
To: Nick Lappos
Regarding you first point: I don’t feel chastised by you correcting me in the use of spanwise bending. It seems that every generation must make their mark on the industry in which they work and one way to do that is to change the definition(s) that apply to different elements. When I first started to work at the Flying S I was told that the reason the inboard pockets were tied together is to minimize spanwise bending. I was also told that the spars on the S-58 rotor blades had Omega Beads running the interior length of the spar in order to stiffen it to resist spanwise bending and when I worked at Bell I was told that the drag links at the root of the blades were to react the loads from spanwise +/- movement of the blades. Now they use the term “edgewise” so the next time I have to refer to this phenomenon I will use the term edgewise as opposed to spanwise.
Regarding your second point, I am very familiar with failure mode(s). In some cases even massive cracks in a blade do not manifest themselves in vibration. Case in point; An USCG HO3S-1G was on a rescue mission to the GOM to remove fisherman from a disabled trawler. On the first trip out one blade severed a mast guy wire. Upon landing the blade was inspected and the ding was worked out. After two more tips without incident the helicopter returned to base and the blade was found to have a crack running from the leading edge to the rear of spar. The pilot was not aware of any adverse vibration. The blade was removed and the damaged area cut out and returned to Sikorsky with many thanks for building such strong blades.
Regarding your third point I mean no disrespect but your experience has been mainly with Sikorsky and I realize that you interface with other manufacturers. However many if not most manufacturers in the aircraft industry will do whatever is necessary to protect them in the event of an accident. While on contract to a major airframe manufacturer I was invited to attend a meeting that was conducted by a law firm from Seattle. This firm is on retainer to just about every airframe manufacturer and if a supplier is also involved this firm will also make this same presentation to them as well. The gist of the presentation is to obfuscate, cover up, hiding of records and where required destruction of the records. Many manufacturers of aircraft practice everything that Arthur Anderson did that resulted in their being charged by the Justice department. It is quite possible that this law firm is on retainer to Sikorsky. If you want their name, E-mail me and I’ll send it to you and you can check.
Regarding your fourth point I agree. If you check back to my post you will see that I indicated that if a firm changed the design or modified a procedure as a result of an accident they are not charged. This is a basic tenant of reliability and for warrantee of aircraft systems. If an accident occurs during the warranty of an aircraft design and the manufacturer makes the necessary change the failure that caused the accident is not chargeable. Regarding legal cover-ups’ refer to point three above.
Regarding your fifth point I agree. This is the way it should be however it is not always so. Management because of costs or schedules or both may still override sometimes when the engineers agree on the correct solution to the problem. This same means of considering cost versus repair is allowed by the FAA. On a major accident the FAA will perform a cost benefit analysis to determine if it is cheaper to make the repair or take the chance that the same accident may never happen again. This analysis considers the cost to the manufacturer, the cost to the operator(s) of the system and the cost of human lives. This cost benefit analysis was performed on TWA-800 among many other accidents including the rudder problems on the 737.
Regarding your sixth point, this is good advice. However when I made certain comments about the design of a certain helicopter I received a great deal of vitriol because certain members of this forum could not accept that criticism due to not understanding the problems or out of pure product loyalty. In response to heliports indication that I was bordering on libel that is not true. If I made certain comments about specific manufactures and their products it was all true and could be substantiated. Regarding his comment about Mr. Robinson coming onto the forum to challenge me about the 18-degree offset you will please note that that is the only thing he addressed and not the other things I found deficient in the design.
Regarding you first point: I don’t feel chastised by you correcting me in the use of spanwise bending. It seems that every generation must make their mark on the industry in which they work and one way to do that is to change the definition(s) that apply to different elements. When I first started to work at the Flying S I was told that the reason the inboard pockets were tied together is to minimize spanwise bending. I was also told that the spars on the S-58 rotor blades had Omega Beads running the interior length of the spar in order to stiffen it to resist spanwise bending and when I worked at Bell I was told that the drag links at the root of the blades were to react the loads from spanwise +/- movement of the blades. Now they use the term “edgewise” so the next time I have to refer to this phenomenon I will use the term edgewise as opposed to spanwise.
Regarding your second point, I am very familiar with failure mode(s). In some cases even massive cracks in a blade do not manifest themselves in vibration. Case in point; An USCG HO3S-1G was on a rescue mission to the GOM to remove fisherman from a disabled trawler. On the first trip out one blade severed a mast guy wire. Upon landing the blade was inspected and the ding was worked out. After two more tips without incident the helicopter returned to base and the blade was found to have a crack running from the leading edge to the rear of spar. The pilot was not aware of any adverse vibration. The blade was removed and the damaged area cut out and returned to Sikorsky with many thanks for building such strong blades.
Regarding your third point I mean no disrespect but your experience has been mainly with Sikorsky and I realize that you interface with other manufacturers. However many if not most manufacturers in the aircraft industry will do whatever is necessary to protect them in the event of an accident. While on contract to a major airframe manufacturer I was invited to attend a meeting that was conducted by a law firm from Seattle. This firm is on retainer to just about every airframe manufacturer and if a supplier is also involved this firm will also make this same presentation to them as well. The gist of the presentation is to obfuscate, cover up, hiding of records and where required destruction of the records. Many manufacturers of aircraft practice everything that Arthur Anderson did that resulted in their being charged by the Justice department. It is quite possible that this law firm is on retainer to Sikorsky. If you want their name, E-mail me and I’ll send it to you and you can check.
Regarding your fourth point I agree. If you check back to my post you will see that I indicated that if a firm changed the design or modified a procedure as a result of an accident they are not charged. This is a basic tenant of reliability and for warrantee of aircraft systems. If an accident occurs during the warranty of an aircraft design and the manufacturer makes the necessary change the failure that caused the accident is not chargeable. Regarding legal cover-ups’ refer to point three above.
Regarding your fifth point I agree. This is the way it should be however it is not always so. Management because of costs or schedules or both may still override sometimes when the engineers agree on the correct solution to the problem. This same means of considering cost versus repair is allowed by the FAA. On a major accident the FAA will perform a cost benefit analysis to determine if it is cheaper to make the repair or take the chance that the same accident may never happen again. This analysis considers the cost to the manufacturer, the cost to the operator(s) of the system and the cost of human lives. This cost benefit analysis was performed on TWA-800 among many other accidents including the rudder problems on the 737.
Regarding your sixth point, this is good advice. However when I made certain comments about the design of a certain helicopter I received a great deal of vitriol because certain members of this forum could not accept that criticism due to not understanding the problems or out of pure product loyalty. In response to heliports indication that I was bordering on libel that is not true. If I made certain comments about specific manufactures and their products it was all true and could be substantiated. Regarding his comment about Mr. Robinson coming onto the forum to challenge me about the 18-degree offset you will please note that that is the only thing he addressed and not the other things I found deficient in the design.
Iconoclast
Joined: Sep 2000
Posts: 2,132
Likes: 0
From: The home of Dudley Dooright-Where the lead dog is the only one that gets a change of scenery.
In or out?
For all of you that have a vested interest in the argument about Centrifugal Vs Centripetal please read the patent for the Robinson rotor head. Count the number of time he uses Centrifugal forces as opposed to Centripetal forces.
http://patft.uspto.gov/netacgi/nph-...AND+AN/Robinson
http://patft.uspto.gov/netacgi/nph-...AND+AN/Robinson
Joined: Nov 2000
Posts: 452
Likes: 0
From: Vancouver, BC, Canada
Nick,
I take the liberty of elaborating on your point 6).
______________________
Western societies are witnessing an exponential growth in the promotional and marketing aspects of product creation and distribution. This hyperbole is extremely evident in the movie industry and the stock market.
Another growth industry is the confrontational one of civil legal actions.
I agree with you that no person, institution, company or government has the right to make insupportable derogatory remarks about another. But, I also strongly believe that the members of a society must have the right to question those things, which others in the society so freely hype.
I'm sure you agree that no one should be denied the right to present fair and honest criticism.
______________________
P.S. Was it a good piano concert?
I take the liberty of elaborating on your point 6).
______________________
Western societies are witnessing an exponential growth in the promotional and marketing aspects of product creation and distribution. This hyperbole is extremely evident in the movie industry and the stock market.
Another growth industry is the confrontational one of civil legal actions.
I agree with you that no person, institution, company or government has the right to make insupportable derogatory remarks about another. But, I also strongly believe that the members of a society must have the right to question those things, which others in the society so freely hype.
I'm sure you agree that no one should be denied the right to present fair and honest criticism.
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P.S. Was it a good piano concert?
Last edited by Dave Jackson; 5th July 2002 at 03:34.
Joined: Jun 2002
Posts: 820
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From: New York City
HeliGaz says
Answer (or partly the answer) is when Flight Instructors take the checks seriously and teach students properly how to do one.
Too many of them don't even ensure the student knows how to do a proper pre-flight. They run through it a couple of times at the beginning of training and then send the student ahead while they have a coffee.
That's how it is here.
Is it any better in the UK? I doubt it.
when will people learn to do a THOROUGH 'A' check?
Too many of them don't even ensure the student knows how to do a proper pre-flight. They run through it a couple of times at the beginning of training and then send the student ahead while they have a coffee.
That's how it is here.
Is it any better in the UK? I doubt it.
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Posts: n/a
Dave,
Your clarifications are important. I believe that the posts we all make can and should contain all aspects of experiences, fact and opinion, and I respect the absolute right we have to voice these. It is attacks on the integrity or motives of people who (by nature of having done something) are exposed. I say fire away with observations, critiques, negative reports and the like. Just shy away from trying to ascribe motives of greed or failures of integrity without definate proof.
The challanges we hand each other, the debates and disagreements keep the site alive!
Your clarifications are important. I believe that the posts we all make can and should contain all aspects of experiences, fact and opinion, and I respect the absolute right we have to voice these. It is attacks on the integrity or motives of people who (by nature of having done something) are exposed. I say fire away with observations, critiques, negative reports and the like. Just shy away from trying to ascribe motives of greed or failures of integrity without definate proof.
The challanges we hand each other, the debates and disagreements keep the site alive!
Joined: Jul 2002
Posts: 16
Likes: 0
From: Cheshire
bronx, i agree entirely my students all get shown a VERY thorough 'a' check, and as well as the factory list, i show where i have(or i have heard of ) had any problems etc.the more hours i do the more paranoid i get!
my students are not only my job but most also become good friends that i would not want to lose.
i also try to get over the 'if in doubt ask' mentality, i am not unapproachable, and they know it, wether it is for confirmation or advice they can (and do) ask
i know that some instructors just do the job to gain hours prior to 'going comercial' but i consider myself a career instructor and have no wish to do that. the better my students are the better i look when they go to any l/s
my students are not only my job but most also become good friends that i would not want to lose.
i also try to get over the 'if in doubt ask' mentality, i am not unapproachable, and they know it, wether it is for confirmation or advice they can (and do) ask
i know that some instructors just do the job to gain hours prior to 'going comercial' but i consider myself a career instructor and have no wish to do that. the better my students are the better i look when they go to any l/s