Robinson R44
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R44 Blade debonding AD
A new AD has come out from the CASA website.
Click Here
Although it is not specified on the AD, rumour has it that an R44 may have suffered M/R blade skin debonding (near the tips) in flight.
1. Has anyone else noticed this occurung on R44 blades?
2. If debonding happened in flight with skin peeling back to the extent of causing moderate to severe vibration, would a "power off" autorotation be a safe option?
Click Here
Although it is not specified on the AD, rumour has it that an R44 may have suffered M/R blade skin debonding (near the tips) in flight.
1. Has anyone else noticed this occurung on R44 blades?
2. If debonding happened in flight with skin peeling back to the extent of causing moderate to severe vibration, would a "power off" autorotation be a safe option?
Join Date: Jul 2002
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oh dear, old man rotor strikes again!
i dont mean to moan about any other rotary pilots but the quote 'an auto in any R heli'.......isnt safe , what utter tosh!
from previous posts i assume you are an ' old bold pilot' on large twins, well news for you, not everyone wants or can afford to fly twins- twice the trouble and as the pilot of G-SAEW found out having 2 donkeys on top doesnt stop you having an accident(no disrespect to the guy, i think he did an exellent job in the circumstances, just using it as an illustration)
also as most are filled with fuel from the same filler neck, get bad fuel and both engines stop-how many eols have you performed recently in your flashy twin?
yes the r22 can be difficult to get it right but any problems are mostly down to pilot inexperience or lack of currency than a bad design, and as for the r44 it autos almost exactly like a 206-regarded by most as the safest single engine helo
if people in the industry can be so blinkered how are we to beat the likes of the mirror in thier latest campaign?
i dont mean to moan about any other rotary pilots but the quote 'an auto in any R heli'.......isnt safe , what utter tosh!
from previous posts i assume you are an ' old bold pilot' on large twins, well news for you, not everyone wants or can afford to fly twins- twice the trouble and as the pilot of G-SAEW found out having 2 donkeys on top doesnt stop you having an accident(no disrespect to the guy, i think he did an exellent job in the circumstances, just using it as an illustration)
also as most are filled with fuel from the same filler neck, get bad fuel and both engines stop-how many eols have you performed recently in your flashy twin?
yes the r22 can be difficult to get it right but any problems are mostly down to pilot inexperience or lack of currency than a bad design, and as for the r44 it autos almost exactly like a 206-regarded by most as the safest single engine helo
if people in the industry can be so blinkered how are we to beat the likes of the mirror in thier latest campaign?
Iconoclast
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Blade debonding.
Debonding of the blade skin may be a manufacturing anomaly or it could be caused by the use of unapproved cleaning or protective materials. Check the Robinson forum on Vertical Reference under “Corrosion”. It is apparent that Robinson operators and by extension all operators are using unapproved materials to protect their helicopters from corrosion. One Robinson pilot from Australia indicated that they used a product called Nutcreaker, which he said far out performs WD-40 which most certainly would result in debonding. Check it out.
Hope I'm not out of line...
Just wanted to get back to the original topic, I personnaly don't think entering an auto would help the matter, since the NR would likely remain the same, or higher at some stages. The debonding of the Blades would cause vibrations, and if I experienced severe low-frequency vibrations I would land ASAP no matter what machine I was in.
ABout the Robbo and auto's, they glide a lot better than the "greased anvil" i currently fly, my only gripe is that you have to be a bit more on the ball should the donkey decide to go on strike
Well, those words were my opinion anyways...
ABout the Robbo and auto's, they glide a lot better than the "greased anvil" i currently fly, my only gripe is that you have to be a bit more on the ball should the donkey decide to go on strike
Well, those words were my opinion anyways...
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I have heard that the Robbos can be tricky in auto, more so the R22, and good training is important.
Winnie: I was thinking that if the blade skins debonded in flight, then the disturbance in the airflow would act a bit like a speed brake in a wing, particularly if some of the skin were protruding outwards.
Entering an auto with reduced or no power (IMHO), could allow the rotor RPM to slow down below the minimum limit.
All opinions are welcome!
Lu: Yes I agree that unapproved materials being used for these sorts of things happens a lot.
WD40 has a lot of competition in the commercial market and operators will generally use what they consider a cheap alternative if WD40 is scarce.
I’ve also heard that the scrim used in bonding can act as a wick, which draws moisture and chemicals into the bond line when the sealing surfaces erode .
Are there alternatives to the use of scrim?
Winnie: I was thinking that if the blade skins debonded in flight, then the disturbance in the airflow would act a bit like a speed brake in a wing, particularly if some of the skin were protruding outwards.
Entering an auto with reduced or no power (IMHO), could allow the rotor RPM to slow down below the minimum limit.
All opinions are welcome!
Lu: Yes I agree that unapproved materials being used for these sorts of things happens a lot.
WD40 has a lot of competition in the commercial market and operators will generally use what they consider a cheap alternative if WD40 is scarce.
I’ve also heard that the scrim used in bonding can act as a wick, which draws moisture and chemicals into the bond line when the sealing surfaces erode .
Are there alternatives to the use of scrim?
Iconoclast
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Huh?
Not sure what scrim is? If it is a sealant then yes petroleum and caustic detergent materials can wick into the bonding material and cause the fracture or deterioration of the bond. We washed our Sikorsky blades with castile soap and DI water or bottled water, which had minimal mineral content. We used to wax our helicopters because we spent a lot of time aboard ship. I tried the wax on the blades and the mineral spirits in the wax caused a debond on the blade pockets. That stopped very soon thereafter.
I can't say this LOUD enough. Don't use WD-40 for anything on an aircraft unless the manufacturer of the aircraft for that particular function approves it. I believe Allison approves it for long term storage of an engine on aircraft and the WD-40 is not used as a preservative. WD in WD-40 stands for Water Dispersant. Also the fumes from WD-40 can cause some serious medical problems if it is ingested into the lungs or into the stomach for whatever reason. Read the label. I assume that other similar products can cause the same problems.
I can't say this LOUD enough. Don't use WD-40 for anything on an aircraft unless the manufacturer of the aircraft for that particular function approves it. I believe Allison approves it for long term storage of an engine on aircraft and the WD-40 is not used as a preservative. WD in WD-40 stands for Water Dispersant. Also the fumes from WD-40 can cause some serious medical problems if it is ingested into the lungs or into the stomach for whatever reason. Read the label. I assume that other similar products can cause the same problems.
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Scrim
It is the word I use for the gauze/fabric that is used in between two bonded surfaces (sometimes).
I think it maintains a constant thickness between joints and helps retain the adhesive while it is still curing during the bonding process.
I think it maintains a constant thickness between joints and helps retain the adhesive while it is still curing during the bonding process.
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The recent debonding event happened about 20 miles from here and was one of my friends machines. The scenario was the pilot was on approach to the airport, felt vibrations and lost rotor RPM.
Entered an auto, but found still had some power and did a low powered "auto". Bad news was that the clear spot he picked short of the airfield was actually a nest of power lines (The airport is right next to major electricity sub station with both high tension and 240 volt lines every where. Not a bright place for them but the airport was there first
Anyway, clipped a lone wire just above the ground and probably took out the tail rotor. At some point the aircraft started rotating and settled on the skids while rotating and proceded to thrash itself to bits. Both pilot and passenger walked away, though the pilot had some squashed vertebrae, I'm told.
As for the use of WD 40 etc. It's use is ubiquitous here. Mostly its used on the leading of blades to prevent corrosion because of the high salt content and very high humidity in the air. If you use nothing the blades rapidly develop corrosion on the D Spar or on the skin where the paint has worn off.
Now whether or not the operator used WD 40, one has to bear in mind that there are at least 6 R44s (and several have been through rebuilds so are on second or third sets of blades)operating in this area and several R22s. Most use WD 40 (so do the local Bell operators as well) and of the 10,000s of hours the local sets of blades have had up on them over the last say ten years there has been one blade debond here (I don't know where the other blade mentioned in the CASA report was) That blade was getting close to its 2200 hours I think. They were put new on that machine only about two years ago so they have seen plenty of use in a short time.
I would have to say that with all due respect to Mr. Zuckerman, recalling events that happened in 1952 and using them as evidence for or against current practice is a bit of a long bow to draw. The bonding agents were probably not even invented then. Similarly putting your ideas on one forum and then quoting that forum as a source of evidence against a practice is also a pretty rude trick. Your negative comments on the Vertical Reference forum merely echo your statements here and yours were the only ones backing your statements.
I'm not trying to be smart or nasty just trying to keep an even keel on the debate. You may after all be right. But your evidence is not yet that convincing.
Anyway, the obvious answer is to contact Robinson and get their word on it. I have written to them and will post the answer when they write back.
Entered an auto, but found still had some power and did a low powered "auto". Bad news was that the clear spot he picked short of the airfield was actually a nest of power lines (The airport is right next to major electricity sub station with both high tension and 240 volt lines every where. Not a bright place for them but the airport was there first
Anyway, clipped a lone wire just above the ground and probably took out the tail rotor. At some point the aircraft started rotating and settled on the skids while rotating and proceded to thrash itself to bits. Both pilot and passenger walked away, though the pilot had some squashed vertebrae, I'm told.
As for the use of WD 40 etc. It's use is ubiquitous here. Mostly its used on the leading of blades to prevent corrosion because of the high salt content and very high humidity in the air. If you use nothing the blades rapidly develop corrosion on the D Spar or on the skin where the paint has worn off.
Now whether or not the operator used WD 40, one has to bear in mind that there are at least 6 R44s (and several have been through rebuilds so are on second or third sets of blades)operating in this area and several R22s. Most use WD 40 (so do the local Bell operators as well) and of the 10,000s of hours the local sets of blades have had up on them over the last say ten years there has been one blade debond here (I don't know where the other blade mentioned in the CASA report was) That blade was getting close to its 2200 hours I think. They were put new on that machine only about two years ago so they have seen plenty of use in a short time.
I would have to say that with all due respect to Mr. Zuckerman, recalling events that happened in 1952 and using them as evidence for or against current practice is a bit of a long bow to draw. The bonding agents were probably not even invented then. Similarly putting your ideas on one forum and then quoting that forum as a source of evidence against a practice is also a pretty rude trick. Your negative comments on the Vertical Reference forum merely echo your statements here and yours were the only ones backing your statements.
I'm not trying to be smart or nasty just trying to keep an even keel on the debate. You may after all be right. But your evidence is not yet that convincing.
Anyway, the obvious answer is to contact Robinson and get their word on it. I have written to them and will post the answer when they write back.
Iconoclast
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Yeah but....
To: RobboRider
I made a point about what can happen and used a personal experience to illustrate the point. Granted it happened in 1952 but you seemed to have missed the point.
What I suggested was that WD-40 is not a preservative. Its' sole purpose is to displace water. WD-40 was developed to protect the stainless steel skin of the Atlas Missile and it was not called WD-40 at that time. WD-40 like liquid Wrench and other similar products is capable of weeping into very tiny crevasses on metal surfaces and in the process it displaces water where Liquid wrench penetrates rusted surfaces. All of these products contain petroleum distillates that can react with the bonding material.
My second point is that you can not use a product in the maintenance and servicing of an aircraft if that product is not approved for that function. The aircraft manufacturer will run tests or they will have the product manufacturer submit the product to an approved laboratory for testing for the intended function. If the product is not in the approved materials list in the maintenance handbook then it can't be used. Also, if WD-40 is approved you must only use it for the approved purpose.
Also, if you use WD-40 on the blades as a preservative the film of WD-40 will attract sand and other entrained particles and upset the delicate aerodynamics of the blades.
I have worked as a Reliability, Maintainability and Systems Safety Consultant since 1968 and problems like this are constantly being raised.
I made a point about what can happen and used a personal experience to illustrate the point. Granted it happened in 1952 but you seemed to have missed the point.
What I suggested was that WD-40 is not a preservative. Its' sole purpose is to displace water. WD-40 was developed to protect the stainless steel skin of the Atlas Missile and it was not called WD-40 at that time. WD-40 like liquid Wrench and other similar products is capable of weeping into very tiny crevasses on metal surfaces and in the process it displaces water where Liquid wrench penetrates rusted surfaces. All of these products contain petroleum distillates that can react with the bonding material.
My second point is that you can not use a product in the maintenance and servicing of an aircraft if that product is not approved for that function. The aircraft manufacturer will run tests or they will have the product manufacturer submit the product to an approved laboratory for testing for the intended function. If the product is not in the approved materials list in the maintenance handbook then it can't be used. Also, if WD-40 is approved you must only use it for the approved purpose.
Also, if you use WD-40 on the blades as a preservative the film of WD-40 will attract sand and other entrained particles and upset the delicate aerodynamics of the blades.
I have worked as a Reliability, Maintainability and Systems Safety Consultant since 1968 and problems like this are constantly being raised.
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I spoke to the LAME who looks after the R44 that debonded the blade and he told me categorically that those blades have not been treated with WD 40. As I trust him implicitly (he does my machine as well, I am prepared to say "That answers the question" - in relation to the blade which did debond. They wash them with standard detergent and that's it. Unauthorised cleaning agents had nothing to do with it.
Also found out the blades had 700 hours to run and were 4 years old (not the two I thought - time flies. I remember when they were installed and didn't realise it was that long ago.
No wonder I'm feeling old. Time is speeding up!)
I also got back a reply from Robinson which despite a specific question about WD 40 was only a very general answer. They advise using automotive wax.
I'll post their reply on my website (If it fails try again later It might take me a while to get around to it.)
Go to http://helipics.homestead.com
Also found out the blades had 700 hours to run and were 4 years old (not the two I thought - time flies. I remember when they were installed and didn't realise it was that long ago.
No wonder I'm feeling old. Time is speeding up!)I also got back a reply from Robinson which despite a specific question about WD 40 was only a very general answer. They advise using automotive wax.
I'll post their reply on my website (If it fails try again later It might take me a while to get around to it.)
Go to http://helipics.homestead.com
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R44 Helipods
Any of you out there use or have used the Helipod for the R44?
Are they worth the investment, in terms of ease of use and functionality?
How do they affect the aircraft's performance, and what, if any, drawbacks are there? Can they hold for example, a standard airline-allowed rollaboard case?
Thx in advance.....
Are they worth the investment, in terms of ease of use and functionality?
How do they affect the aircraft's performance, and what, if any, drawbacks are there? Can they hold for example, a standard airline-allowed rollaboard case?
Thx in advance.....
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RobboRider
would the lame know if WD40 had been used by the pilot?
i wonder if the debonding happend on the top or bottom of the blade first (i think i should buy a ladder) and i wonder if flying in the rain after the paint at the tips has been worn off, has anything to do with it?
just thinking out loud.
i wonder if the debonding happend on the top or bottom of the blade first (i think i should buy a ladder) and i wonder if flying in the rain after the paint at the tips has been worn off, has anything to do with it?
just thinking out loud.
Iconoclast
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What goes around comes around.
I also got back a reply from Robinson which despite a specific question about WD 40 was only a very general answer. They advise using automotive wax.
It was stated that their operator used plain household detergent to clean the blades. Detergents in some countries can contain Sodium Meta silicate penta hydrate, which is highly alkaline or possibly monobutyl ether, which is a solvent. I would suggest that you return to the dark ages of 1952 and use Castile soap and deionized water to wash the blades and go back to Robinson and ask them which car wax and detergent they recommend. That way, you are protected if you experience debonding or any other problem and it is traced to the use of the recommended products. .
Run Henney Penney the sky is falling or, is it Wolf, Wolf!