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Longline Faliures


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Just wondering how many people have had a longline snap in flight, and did it cause any damage to the machine. It just happened to me. 50ft kelvar line snap approx haft way down, the upper haft all most cut the horz stab in haft and scrapped one main blade. The pilot landed safely and no other damage to the aircraft. it was the second lift of the year for that line, and visually looked fine. Haven't found the bottom haft of the line yet to see if that will give anymore reason for the failure. I would like to hear everyone else stories, inspection process, line maintenance tips and if anyone puts a life on the line.

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Incredible! What kind of machine were you flying?

Also, aside from this unlikely event which has happened. Does not testing a line add new stress to the long line now?

It was my understanding that a long line has way more tensil strength then whatever a machine will ever lift. Which is why when whomever tests a line are they not loading up a line to the point it is certified for? Which now decreases the life of the line does it not.

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Superwrench if indeed you were using Kevlar it is no wonder it broke as it is crap, it is brittle, the thimble for the eye should be minimum of twice diameter for any other product due to this, it is susceptable to UV damage, fuel contamination plus many others. Peace Helicopters lost a drill in early 90's with Kevlar and never used them again, they switched to Spectra which then had a brand name change to Amsteel Blue.

 

Amsteel is not at all like this, and would not recoil to aircraft. Cougar helicopters had a 4500 lb load on a Amsteel line and the line broke due to being contacted by a cliff and the line did nothing. There is something like .01% elasticity in an Amsteel Blue line far less the steel cable.

 

The only way something like Amsteel Blue would come up to the aircraft is if a nylon or steel lanyard broke and the elasticity in that could drive the light synthetic line up to aircraft.

 

As was mentioned in a long ago thread these sythetic lines are very susceptable to heat damage, Amsteel begins to lose its strength at 165' F so has to be kept away from heat source such as exhaust of 500D while landing.

 

Amsteel is used in very harsh evironments such as logging, tugboats, and fishing line but it should be kept clean and away from heat.

 

sc

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Superwrench if indeed you were using Kevlar it is no wonder it broke as it is crap, it is brittle, the thimble for the eye should be minimum of twice diameter for any other product due to this, it is susceptable to UV damage, fuel contamination plus many others. Peace Helicopters lost a drill in early 90's with Kevlar and never used them again, they switched to Spectra which then had a brand name change to Amsteel Blue.

 

Amsteel is not at all like this, and would not recoil to aircraft. Cougar helicopters had a 4500 lb load on a Amsteel line and the line broke due to being contacted by a cliff and the line did nothing. There is something like .01% elasticity in an Amsteel Blue line far less the steel cable.

 

The only way something like Amsteel Blue would come up to the aircraft is if a nylon or steel lanyard broke and the elasticity in that could drive the light synthetic line up to aircraft.

 

As was mentioned in a long ago thread these sythetic lines are very susceptable to heat damage, Amsteel begins to lose its strength at 165' F so has to be kept away from heat source such as exhaust of 500D while landing.

 

Amsteel is used in very harsh evironments such as logging, tugboats, and fishing line but it should be kept clean and away from heat.

 

sc

 

 

I will hapzard a guess here that Superwrench meant to say Spectra/armsteel, and NOT kevlar. Operator in question has been using spectra/armsteel for some years. I suspect he was using the misnomer of kevlar by mistake.

 

Superwrench will probably correct his mistake next time he logs on....if I know him like I think I know him...He is just too busy at the moment replacing a M/R blade and horz. stab....

 

The operator in question is **** lucky to have him on staff.

 

Cheers Superwrench :up:

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Arctic front was right it was a spectra line, and this was on a an a-star. Well this is my best guess at what happened. The pilot was carring a load of playwood in a net, the swivel on the hook appears to have locked up and the line begain the twist. The line failled about 3 ft from the hook, when the remaining part of the line shot up between the t/r and boom and then got in to the blades which then pulled the line through the horz stab and cut the line again. All that happened in a split second. I am not to sure about the lines history. Thanks for all your guys input, and thanks Arctic Front for the compilment.

 

parden any spelling mistakes it is early.

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