Sikorsky S-92: From Design to Operations
Dan,
That one passes me by - what does it mean? I think if you are implying FS simmer you are somewhat wide of the mark.
225, your comments are largely correct.......if a little facetious!
wannabe S-92 carbon-based stick actuator?
225, your comments are largely correct.......if a little facetious!
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Nick Lappos interview
Many of you may have already seen this, but for those that have not, the October issue of Aerospace International has an interesting interview with Nick Lappos, covering amongst other things, the S92 and Comanche.
Link here You will need an account to view online.
PW
Link here You will need an account to view online.
PW
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Can anyone tell me the procedure for loss of XMSN oil in the S-92.In particular, is there a requirement to idle back on an engine?
All in all the situation is not very good, and there is a good deal of room for confusion. There are one or two on this forum who have some much better first hand experience of this, so can maybe explain it better.
In particular, is there a requirement to idle back on an engine?
There are other scenarios that require the action you mention e.g. after an input chip or input hot caution.
"but once the MGB pressure drops below 35psi the red warning light appears and you get an audio warning. One is to then manually operate the MGB OIL BYPASS switch within 5 secs."
I am still amused that on the "all sensing - all doing S-92" the only switch that must be operated immediately (with no options if the "Dire Red Fright Light" illuminates ) within 5 seconds is not automatic - why not? - light on - BYPASS opens. Seems electrically feasible. The switch could be an override if auto switching did not occur.
The placement of the bypass switch on an overhead panel within inches of the fire ext selector switch (which is similar in marking and size) is also brilliant cockpit ergonomics.
Maybe in the "B".
I am still amused that on the "all sensing - all doing S-92" the only switch that must be operated immediately (with no options if the "Dire Red Fright Light" illuminates ) within 5 seconds is not automatic - why not? - light on - BYPASS opens. Seems electrically feasible. The switch could be an override if auto switching did not occur.
The placement of the bypass switch on an overhead panel within inches of the fire ext selector switch (which is similar in marking and size) is also brilliant cockpit ergonomics.
Maybe in the "B".
Could I just point out that the Sea King has had an emergency lube system in the MRGB for many years and that it operates automatically - Modern Technology, dontcha just luvit
Didn't the S-92 designers and engineers look at what the company had already produced and learn some fundamental lessons from it?
Didn't the S-92 designers and engineers look at what the company had already produced and learn some fundamental lessons from it?
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Don't confuse the different MGB designs, folks. The S61 is terrifically vulnerable to loss of lube on its sleeve bearing inputs (sleeve bearings are like the crankshaft journal bearings, where metal slides on metal, vice roller or ball bearings, where the two surfaces essentially roll against each other). For an S61, the loss of oil pressure for more that a minute or two can lead to melting of the inputs and cutting of both engine inputs - a total power loss. The "aux lube" for an S61 is a secondary pressure system for these sleeves to cool and lube them, and prevent dual engine cut in a few minutes.
The S92 has dual independant MGB pumps, each able to sustain acceptable pressure, and has loss of lube protection via the external isolation valve, as well as a quantity sensor and warning system. The transmission was reported to run more than 3 hours during its loss of lube tests. There are no sleeve bearings or such that are vulnerable to the loss of pressure, like the S61.
Yes, they did learn something since the S61, I guess.
The S92 has dual independant MGB pumps, each able to sustain acceptable pressure, and has loss of lube protection via the external isolation valve, as well as a quantity sensor and warning system. The transmission was reported to run more than 3 hours during its loss of lube tests. There are no sleeve bearings or such that are vulnerable to the loss of pressure, like the S61.
Yes, they did learn something since the S61, I guess.
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The placement of the bypass switch on an overhead panel within inches of the fire ext selector switch (which is similar in marking and size) is also brilliant cockpit ergonomics.
I believe that the S92 was designed solely to meet the requirements of FAA/EASA Part 29. I donīt think much attention was put into making it "user friendly" in terms of cockpit ergonomics.
Last edited by rotordude; 25th Feb 2009 at 21:55.
Ramen - the Sea King MRGB is different to the S61 then - the sleeved white metal bearings were replaced by rollers many moons ago and the ELS uses oil from the torquemeter system to lubricate the inputs.
Your defence of the 92 box seems to fly in the face of some of the criticism here.
Your defence of the 92 box seems to fly in the face of some of the criticism here.
Ramen
Apparently S-92 pilots only have five seconds to survive the loss of one pump which apparently can wear out in under 100 hours. 5 secs/100 hours I will fly an S-61 anytime.
The Sultan
Apparently S-92 pilots only have five seconds to survive the loss of one pump which apparently can wear out in under 100 hours. 5 secs/100 hours I will fly an S-61 anytime.
The Sultan
sultan, you are talking nonsense 
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Didn't the S-92 designers and engineers look at what the company had already produced and learn some fundamental lessons from it?
If they had done this we would have a few more blades whirling over our tormented heads
It does beg the question why that particular situation should require a pilot's action instead of producing a caution light to tell you the automatic system had actuated.
Why the change from the 61 method to the 92 method?
Was there something in the certification requirements that forced that?
Albatross beat me to it but Ramen overlooked that part of his explanation on the 92 MGB design.
What say you Ramen? Or any others knowing the answers?
Why the change from the 61 method to the 92 method?
Was there something in the certification requirements that forced that?
Albatross beat me to it but Ramen overlooked that part of his explanation on the 92 MGB design.
What say you Ramen? Or any others knowing the answers?
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Ramon Says:
bearing inputs (sleeve bearings are like the crankshaft journal bearings, where metal slides on metal, vice roller or ball bearings, where the two surfaces essentially roll against each other).
Oh really Ramon, what do you reckon the oil does, think oil wedge theory etc.
Blackhand
bearing inputs (sleeve bearings are like the crankshaft journal bearings, where metal slides on metal, vice roller or ball bearings, where the two surfaces essentially roll against each other).
Oh really Ramon, what do you reckon the oil does, think oil wedge theory etc.
Blackhand
Was the final report ever released on what the root cause of event 212man had and discussed in the #950 area messages on this thread? #979 is extremely interesting.
The Sultan
The Sultan
http://www.pprune.org/rotorheads/163...ations-48.html check post 948 about the Brunei incident paige 48-50, comments like
.
It is sad thinking about what happend two days ago...
I'm glad it wasn't Cougar, CHC or BHL on a revenue flight.
It is sad thinking about what happend two days ago...