Airframe life of S61? Plus how much is an S92?
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http://www.carsonhelicopters.com/composite_blades.htm
both i guess
they quote 10K hrs life on the tin blades , is that on the cuffs only . If you replace cuffs with zero TSN cuffs do you have 10k more hrs ?
both i guess
they quote 10K hrs life on the tin blades , is that on the cuffs only . If you replace cuffs with zero TSN cuffs do you have 10k more hrs ?
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Originally Posted by NickLappos
Widg, I don't know what that means, since the S61 and the S76 and the S92 were all designed to have no life limit on the fuselage. This is perfomed by designing the fuselage so that the stresses are low enough to assure no fatigue failures, and then the monitoring and updating in areas where field experience proves this not to be true. I believe at least one S76 has also reached 40,000 hours.
Could you point me in a direction to learn more about heli industry practices?
Mart
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Graviman,
The concepts between the two metals (Al and steel) is quite similar. The value we use for the max stress to allow infinite life is called the "endurance" level, and is determined for each type of material by coupon tests, then adjusted for shapes and stress risers for any given design (K factors and knock downs). For critical parts, real data is taken by breaking parts, but airframes are not generally of that class, since they are designed with redundant load paths and a great deal of inspectability. Airframe stress gages compare flight loads to predicted loads to assure design adequacy, and beefups are applied if necessary during flight test.
There is a FAA AC on fatigue testing, and I believe some great AHS papers over the years. If you are building something commercial, I can recommend some expert friends!
Nick
The concepts between the two metals (Al and steel) is quite similar. The value we use for the max stress to allow infinite life is called the "endurance" level, and is determined for each type of material by coupon tests, then adjusted for shapes and stress risers for any given design (K factors and knock downs). For critical parts, real data is taken by breaking parts, but airframes are not generally of that class, since they are designed with redundant load paths and a great deal of inspectability. Airframe stress gages compare flight loads to predicted loads to assure design adequacy, and beefups are applied if necessary during flight test.
There is a FAA AC on fatigue testing, and I believe some great AHS papers over the years. If you are building something commercial, I can recommend some expert friends!
Nick
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What ever happened to the original Chevron/ Bristow/ UNST S61's?
G-BAKC G-BFRI G-BFMY?????? the original team??????????
Russ S /Clive V / Pete C/ Michel Z/ Jaque Gassolene! and so many great guys' that linked the Ninian with Unst 79-93- they all deserve MBE's
Can anybody post some pictures please?
G-BAKC G-BFRI G-BFMY?????? the original team??????????
Russ S /Clive V / Pete C/ Michel Z/ Jaque Gassolene! and so many great guys' that linked the Ninian with Unst 79-93- they all deserve MBE's
Can anybody post some pictures please?
Last edited by Bacon Slicer; 8th Dec 2006 at 00:37. Reason: .
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G-BAKC Transferred to France in 1987
G-BFRI Now with BIH Penzance
http://www.caa.co.uk/applicationmodu...01&imgtype=jpg
G-BFMY Transferred to Brazil in 2000
G-BFRI Now with BIH Penzance
http://www.caa.co.uk/applicationmodu...01&imgtype=jpg
G-BFMY Transferred to Brazil in 2000
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Bacon Slicer,
The Ninians are again (temporarily) being serviced by S61, flying out of Scatsta, while 332s are in short supply following last month's rollover.
Of the pilots ypu name, most are now in well earned retirement, though I believe that Pete C is still flying in some distant land.
OA
The Ninians are again (temporarily) being serviced by S61, flying out of Scatsta, while 332s are in short supply following last month's rollover.
Of the pilots ypu name, most are now in well earned retirement, though I believe that Pete C is still flying in some distant land.
OA
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Originally Posted by NickLappos
There is a FAA AC on fatigue testing, and I believe some great AHS papers over the years. If you are building something commercial, I can recommend some expert friends!
Related technical papers:
AHS technical papers
Airframe Fatigue
If you wanted to PM me the expert friend contact details, i guarantee that i would treat the exercise with the level of commercial sensitivity befitting a professional engineer.
Warmest regards,
Mart
Last edited by Graviman; 8th Dec 2006 at 20:00. Reason: Error in AHS link.
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I am currently swinging spanners on a 44000 PLUS time 61 and she is in good shape. I see no reason why they can't go on indefinitely as long as Sikorsky keeps supplying parts or if they sell the type certification on when they deem it no longer viable a-la Skycrane/Ericson's.
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Bacon
Pete C was flying with Bristow in Oz out of Essendon until a few months ago, I think he has just decided to retire for good now.
Michel was last known as a 332L2 simulator instructor at Helisim in Marignane.
Don't know anything of Jaques.
They were the days though, a Heavy Chevy out of Unst in BFRI, 3 trips, the first with the hayboxes to bring the food into the Unst terminal, drinks at the Baltasound hotel and 5 star accommodation in H block until it blew away!!
HH
Pete C was flying with Bristow in Oz out of Essendon until a few months ago, I think he has just decided to retire for good now.
Michel was last known as a 332L2 simulator instructor at Helisim in Marignane.
Don't know anything of Jaques.
They were the days though, a Heavy Chevy out of Unst in BFRI, 3 trips, the first with the hayboxes to bring the food into the Unst terminal, drinks at the Baltasound hotel and 5 star accommodation in H block until it blew away!!
HH
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NICK & MAKILA 1
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Thanks.
EXCREWINGBOD
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That pic of JL in Scatsta is seriously sad. Reminds me of my forebodings when our beancounters sold so many of our 61's in part-exchange (for early 332's I think) and they were stored in Bristow's Sumburgh hangar. They were acquired for pennies and put back into service by other, more savvy people elsewhere. I've got pics of some of them, must dig them out.
----------------
Thanks.
EXCREWINGBOD
---------------
That pic of JL in Scatsta is seriously sad. Reminds me of my forebodings when our beancounters sold so many of our 61's in part-exchange (for early 332's I think) and they were stored in Bristow's Sumburgh hangar. They were acquired for pennies and put back into service by other, more savvy people elsewhere. I've got pics of some of them, must dig them out.
G-ATFM is currently working in Scatsta JL's mate.
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Unlimited life has it's limits. This is copied from the S-92A TCDS
NOTE 4 The term “Unlimited Life” is defined as 30,000 flight hours for the Model S-92A rotorcraft. Operation of individual aircraft beyond 30,000 flight hours is contingent upon a Life Extension Program approved by FAA Engineering
NOTE 4 The term “Unlimited Life” is defined as 30,000 flight hours for the Model S-92A rotorcraft. Operation of individual aircraft beyond 30,000 flight hours is contingent upon a Life Extension Program approved by FAA Engineering
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Olde buses and like fossils...
I had the whimisical pleasure recently of visiting with BIH at Penzance. BJ was indeed in the working mix, but I was told that it was headed for a quieter time and space in the near future. I believe they mentioned that it was well beyond the 40K mark for airframe time. The other ship working the Scillys at the time was EB, another long serving bus. EA is down with the Penguins and still going strong. As an aside, the BIH staff mentioned that they had picked up a pair (?) of ex-Bristow 61's to freshen the fleet mix. I recall that they were both manufactured in the late 70's, (among the last off the line?)
Ahhh the memories...
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s-61's
The two machines that B.I.H bought from Bristows this year about July time. They where both in a poor state. The first one that B.I.H got was G-RI that last flew in the D.R.Congo on the U.N contract it has never flown since. the second was a machine that was getting prepared for another Rich American like G-LAWS that Bristow maintaned for an American Buisness men. From what I gather both machines Where in poor state similar to JL at Longside. They had been stripped down to keep the rest off the S-61 fleet witth spares. But heres hopping the B.I.H get them both airworth once again and maybe B.I.H might might get JL as well. Fantastic Helis the S-61.
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S92mach,
That current S92 restriction is just until the FAA builds some experience in the model, based in successful inspections and field service. The S76 went through similar steps. I recall that there were main and tail rotor blade samples bolted to the roof of the Royal Flight Squadron in Amman Jordan, sunning themselves for years. Every several years, a Sikorsky engineer would take one back home and break it on the testing machines to show that the strength was retained, even after strong sunlight exposure for years.
The S92 has a 50 hour 1st service interval (pilot preflight daily of course) and a 500 hour rolling zone inspection, which can replace the annual if one signs up for that program.
That current S92 restriction is just until the FAA builds some experience in the model, based in successful inspections and field service. The S76 went through similar steps. I recall that there were main and tail rotor blade samples bolted to the roof of the Royal Flight Squadron in Amman Jordan, sunning themselves for years. Every several years, a Sikorsky engineer would take one back home and break it on the testing machines to show that the strength was retained, even after strong sunlight exposure for years.
The S92 has a 50 hour 1st service interval (pilot preflight daily of course) and a 500 hour rolling zone inspection, which can replace the annual if one signs up for that program.