Sikorsky S-76 [Archive Copy]
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Either of the above will provide training, but a Type rating is not required (in the U.S.).
You can get your license in a R22 and then hop in a C+ with 41 hrs total piloting time.
See FAR 61.31
Hoss
You can get your license in a R22 and then hop in a C+ with 41 hrs total piloting time.
See FAR 61.31
Hoss
Join Date: Jan 2004
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S76C Cockpit Noise data
Does anyone have any cockpit noise data from the C model at hand.
In the process of a hearing protection review, which this data would be handy for.
Thanks - FC
In the process of a hearing protection review, which this data would be handy for.
Thanks - FC
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Say Again?
By the way, don't forget it's when the noise stops you have start worrying...
The most painful sound level is in the front row left hand seat of the cabin; the cockpit is not quite so close to the 'box. Some guys use Bose noise attenuating sets and swear by them, but they're not cheap.
None of the Utility models is quiet; I understand the VIP versions are quite different; and they don't even vibrate. Funnily enough manufacturers are shy of cockpit noise level figures, possibly constrained by their lawyers. I once asked for the cockpit noise levels in the AS 330L from the visting sales team; I'm surprised I ever worked again. But then I also flew the Chinook with early Clark headsets and we had a major fight to get our company to appreciate the problem - I recall that NASA did some research with us on the loss of human performance after 5-6 hours of sitting underneath so much angry machinery. The results were never made public as I believe it was paid for by a certain oil major and considered private. The ATCOs at ABZ were quite accustomed to our request to say again our inbound clearances.
Most of us had our hearing checked and found that we could still pass our medicals as the hearing test didn't pick up the problem; actually we were suffering a loss of noise discrimination. Two people talking together, no hearing problem; go to the pub and you can't understand anybody, especially when they call time. So we kept practising.
So keep up the campaign to force recognition of this Health and Safety issue; I wish you all better luck than the "old" generation.
By the way, don't forget it's when the noise stops you have start worrying...
The most painful sound level is in the front row left hand seat of the cabin; the cockpit is not quite so close to the 'box. Some guys use Bose noise attenuating sets and swear by them, but they're not cheap.
None of the Utility models is quiet; I understand the VIP versions are quite different; and they don't even vibrate. Funnily enough manufacturers are shy of cockpit noise level figures, possibly constrained by their lawyers. I once asked for the cockpit noise levels in the AS 330L from the visting sales team; I'm surprised I ever worked again. But then I also flew the Chinook with early Clark headsets and we had a major fight to get our company to appreciate the problem - I recall that NASA did some research with us on the loss of human performance after 5-6 hours of sitting underneath so much angry machinery. The results were never made public as I believe it was paid for by a certain oil major and considered private. The ATCOs at ABZ were quite accustomed to our request to say again our inbound clearances.
Most of us had our hearing checked and found that we could still pass our medicals as the hearing test didn't pick up the problem; actually we were suffering a loss of noise discrimination. Two people talking together, no hearing problem; go to the pub and you can't understand anybody, especially when they call time. So we kept practising.
So keep up the campaign to force recognition of this Health and Safety issue; I wish you all better luck than the "old" generation.
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Take you own data, guys! The Radio Shack meter I bought works fine. Just be sure you know what you are measuring. The number of different scales and systems is boggling, and they don't actually translate. Mostly, the dBA scale is used in regulations. Take several readings with the mike in several places, and then average the data. The meter I use is a digital one, but similar to this:
http://www.radioshack.com/product.as...t%5Fid=33-4050
http://www.radioshack.com/product.as...t%5Fid=33-4050
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rjsquirrel -
Yes, but what will you prove? Only that cockpits are noisy, and the bean counters prefer it that way.
I believe you have to prove a loss of human performance and a resultant degradation in flight safety to the Regulatory Authorities to make headway on this problem. At the moment ships and aircraft are exempt from most Health and Safety Regulations in most countries and the Authorities find the helicopter industry too small to bother with. It barely arises in planks anyway so why bother?
Human Performance can be scientifically measured before and after flight; but like all research it needs funding. There are NO fairy godmothers around.
flipcelia -
I recommend that while working along this line, you and your colleagues buy the best headsets you can afford as an investment in your own sanity; wear them anywhere an engine is running; and ask your engineering department as nicely as you know how if that set may be used in THEIR aircraft - PLEASE! Cos you'll have to wait awhile for the beancounters.
I admit that ; I wish you luck.after a lifetime of helicopters, this subject is close to my heart
Yes, but what will you prove? Only that cockpits are noisy, and the bean counters prefer it that way.
I believe you have to prove a loss of human performance and a resultant degradation in flight safety to the Regulatory Authorities to make headway on this problem. At the moment ships and aircraft are exempt from most Health and Safety Regulations in most countries and the Authorities find the helicopter industry too small to bother with. It barely arises in planks anyway so why bother?
Human Performance can be scientifically measured before and after flight; but like all research it needs funding. There are NO fairy godmothers around.
flipcelia -
I recommend that while working along this line, you and your colleagues buy the best headsets you can afford as an investment in your own sanity; wear them anywhere an engine is running; and ask your engineering department as nicely as you know how if that set may be used in THEIR aircraft - PLEASE! Cos you'll have to wait awhile for the beancounters.
I admit that ; I wish you luck.after a lifetime of helicopters, this subject is close to my heart
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Mr. Toad,
You ask, "What will it prove?"
It will prove that unlike you, I read the question that sparked the thread, which is (try reading it now, if you have a moment!) " Does anyone have any cockpit noise data from the C model at hand."
I do disagree with the point of the thread, as I feel that the noise in a cockpit can be fully reduced with the right headset and earplug combination.
Here is the capability of a David Clark (-24dB rating, -35 in the high freq damage range):
http://www.davidclark.com/HeadsetPgs/h10-20.htm
Typical earplugs add 15 to 25 dBA to that, so available protection is about -40 dBA.
Here are OSHA noise regs, where protection is required at about 90dBA:
http://www.osha.gov/pls/oshaweb/owad...able=STANDARDS
Note that the requirement is that protection is required at 85dBA.
I have no info to say that aircraft operators are exempt from OSHA protection (in the States, of course!)
With -24dB reduction, the cockpit could be at 109 to 114 dBA and still be acceptable.
Here is a table of noise standards worldwide:
http://staff.washington.edu/rneitzel/Standards.htm
Here is the Canadian standard (85 dBA) Note that the phrase "Statutes or regulations covered by other jurisdictions apply to aircraft operations" is inserted in the Occupational Health regs for Aircraft Operatons (Part 29):
http://www.worksafebc.com/law_and_po...rt_7_clean.pdf
You ask, "What will it prove?"
It will prove that unlike you, I read the question that sparked the thread, which is (try reading it now, if you have a moment!) " Does anyone have any cockpit noise data from the C model at hand."
I do disagree with the point of the thread, as I feel that the noise in a cockpit can be fully reduced with the right headset and earplug combination.
Here is the capability of a David Clark (-24dB rating, -35 in the high freq damage range):
http://www.davidclark.com/HeadsetPgs/h10-20.htm
Typical earplugs add 15 to 25 dBA to that, so available protection is about -40 dBA.
Here are OSHA noise regs, where protection is required at about 90dBA:
http://www.osha.gov/pls/oshaweb/owad...able=STANDARDS
Note that the requirement is that protection is required at 85dBA.
I have no info to say that aircraft operators are exempt from OSHA protection (in the States, of course!)
With -24dB reduction, the cockpit could be at 109 to 114 dBA and still be acceptable.
Here is a table of noise standards worldwide:
http://staff.washington.edu/rneitzel/Standards.htm
Here is the Canadian standard (85 dBA) Note that the phrase "Statutes or regulations covered by other jurisdictions apply to aircraft operations" is inserted in the Occupational Health regs for Aircraft Operatons (Part 29):
http://www.worksafebc.com/law_and_po...rt_7_clean.pdf
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S76 C+
Hearing lots of different views on the 76 C+, especially about engine problems, any feedback from the Rotorheads in Nigeria, Macau, or anywhere else where they have put some hours on the C+ would be appreciated.
Cheers,
Tynecastle.
Cheers,
Tynecastle.
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Thanks guys for the comments,
have been doing some study on the matter, and the whole thing is quite interesting. The decibel ratings that are advertised on headset data are more than likely far in excess of what you will actually get.
For example, a well known headset (that a lot of you are probably using) quotes 25db of noise reduction and in independent test only reached between 5 - 11db noise reduction depending on the environment. Its for this reason that one of the best headsets on the market do not quote any level of attenuation because of the wide range of levels that will be achieved depending on the situation (head shape, noise freq's, sunglasses etc).
The other interesting fact to come out of this is that using foam plugs under you existing headset in a crewed environment, while giving you pretty good attenuation may be making your crew deaf if they aren't using plugs as well because the intercom is turned up so loud to compensate!
ANR seems to be the way to go, but once again has it's down falls. Not all ANR will attenuate the freq's required in your operation so care should be taken when selecting your next ANR headset.
FC
have been doing some study on the matter, and the whole thing is quite interesting. The decibel ratings that are advertised on headset data are more than likely far in excess of what you will actually get.
For example, a well known headset (that a lot of you are probably using) quotes 25db of noise reduction and in independent test only reached between 5 - 11db noise reduction depending on the environment. Its for this reason that one of the best headsets on the market do not quote any level of attenuation because of the wide range of levels that will be achieved depending on the situation (head shape, noise freq's, sunglasses etc).
The other interesting fact to come out of this is that using foam plugs under you existing headset in a crewed environment, while giving you pretty good attenuation may be making your crew deaf if they aren't using plugs as well because the intercom is turned up so loud to compensate!
ANR seems to be the way to go, but once again has it's down falls. Not all ANR will attenuate the freq's required in your operation so care should be taken when selecting your next ANR headset.
FC
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flip,
I agree fit is important, and if the ear pieces are too old and hard, it simply wll never seal. My experience is the soft silicon seals (almost sensually soft!) do a great job. Do you have a source for that miserable result?
I agree fit is important, and if the ear pieces are too old and hard, it simply wll never seal. My experience is the soft silicon seals (almost sensually soft!) do a great job. Do you have a source for that miserable result?
Crazy Scandihooligan
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Headset frequency models
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Starting a 76 A++
How are you all starting the A++ in regards to the trigger? Some companys advocate pushing the starter button and going into the gate, then trying to reach up and pull the trigger and pull back and modulate the start. Others pull the trigger down, push the button and move forward and then modulate. Any/all comments appreciated.
In China we "pull" the trigger altho to be pedantic the RFM does say to "hold" the trigger.
"hold" is to "pull" ????
The way I was trained many years ago (when a particular Canadian company took delivery of its first A+ ...yes it was an A+ not an ++ but same throttle) was that if the engine went hot and you had not "PULLED" the trigger ; in your panic to shutdown , you may well jam the throtttle up against the idle stop.....in any case the RFM says you may have to move the throttle back past the throttle idle stop in order to modulate the T5 during start , so why would you not pull the trigger.
The analogy to the above is the 212 where you can hit the idle release switch but if you have a death like grip on that throttle , you will not move it ie the force you are applying to close the twist grip is jamming the cam against the pin and not allowing it to retract thus not allowing closure of the throttle past idle.
The late Peter H. had somewhat similiar happen to him in Bombay on a 212 years ago (he also had a battery problem) and in his desire to stop that awful noise and ever increasing TOT , he pulled the Fire T Handle.....clean out of the instrument panel.
Peter
"hold" is to "pull" ????
The way I was trained many years ago (when a particular Canadian company took delivery of its first A+ ...yes it was an A+ not an ++ but same throttle) was that if the engine went hot and you had not "PULLED" the trigger ; in your panic to shutdown , you may well jam the throtttle up against the idle stop.....in any case the RFM says you may have to move the throttle back past the throttle idle stop in order to modulate the T5 during start , so why would you not pull the trigger.
The analogy to the above is the 212 where you can hit the idle release switch but if you have a death like grip on that throttle , you will not move it ie the force you are applying to close the twist grip is jamming the cam against the pin and not allowing it to retract thus not allowing closure of the throttle past idle.
The late Peter H. had somewhat similiar happen to him in Bombay on a 212 years ago (he also had a battery problem) and in his desire to stop that awful noise and ever increasing TOT , he pulled the Fire T Handle.....clean out of the instrument panel.
Peter
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rjsquirrel -
Thanks for the advice, it's always welcome, if somewhat confused this time. I recommend you stop believing the writing on the box (-40 dba?) and listen to what flipcelia says about actual reduction.
I maintain that the implied point of this very important thread from flipcelia is how to cope with human performance reduction, stress and long-term hearing loss due to extended exposure to excessive noise; otherwise why should we concerned with it?
Esso's figures would be useful if available as they relate to this particular aircraft. When you know the characteristics and frequencies of the multitude of noises then you can select an ANR headset that matches that signature.
MD900 Explorer is correct, Bose sets are good. Some of the guys in Macau are using them, perhaps they would give advice. whether Bose covers the requirement.
Thanks for the advice, it's always welcome, if somewhat confused this time. I recommend you stop believing the writing on the box (-40 dba?) and listen to what flipcelia says about actual reduction.
I maintain that the implied point of this very important thread from flipcelia is how to cope with human performance reduction, stress and long-term hearing loss due to extended exposure to excessive noise; otherwise why should we concerned with it?
Esso's figures would be useful if available as they relate to this particular aircraft. When you know the characteristics and frequencies of the multitude of noises then you can select an ANR headset that matches that signature.
MD900 Explorer is correct, Bose sets are good. Some of the guys in Macau are using them, perhaps they would give advice. whether Bose covers the requirement.
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I guess I am confused. "Headsets don't work, so we must buy a Bose." Isn’t a Bose a headset first, then a noise canceller? The Bose manual says in several places that they only protect low frequency noise, and only when the cups seal properly, which is your gripe about headsets!
It seems this thread has already convicted the old headset technology, and now thinks only a Bose active headset is acceptable, when a Bose depends on its ear cups, too.
Here is a paper that describes how well helmets and earplugs work to suppress noise, and how ANR does not change the noise above about 500 HZ (see Table I which has tons of studies together. It shows that ear muffs (headsets) and helmets work on your head):
http://www.aearo.com/pdf/hearingcons/limits2.pdf
Also, the hearing loss most of us get is high frequency, which is where the Bose does not work. Above about 500 Hz the active nose canceling is not at all effective. Bose used to say that on their web site, probably until they realized that they were losing sales that could be gained if they blurred the distinction between comfort (which they do provide) and protection (which is a very marginal product of the Bose technology). Here is a scientific paper that describes the fact that ANR does NOT protect you better than a good headset (but that the better communications and comfort are good to have.):
http://www.aearo.com/pdf/hearingcons/anr.pdf
Without someone who knows what he is talking about, this thread is wandering into strange territory!
Here is the Bose site, check out their manual, page 19 for example:
http://www.bose.com/controller;jsess...Br5LCs06T7R58J!103858704!-174109993?event=VIEW_PRODUCT_PAGE_EVENT&product=headsetx_hea dset_index&linksource=centernav_img_pilots&pageName=/index_2.jsp
Here is a web site that discusses hearing loss, showing that it usually occurs far above the range where Bose helps:
"When damage first occurs, it usually affects the part of the ear corresponding to the mid-frequency range of 3 to 5 kHz. On an audiogram, this type of hearing loss configuration is commonly referred to as a "noise notch." These frequencies correspond to the region where our consonant sounds are heard. A person with this type of hearing loss may have trouble understanding speech because the speech sounds "muffled"........ because the louder, lower frequency vowels are audible but the softer high frequency consonants are made even more difficult to hear, due to reduced hearing sensitivity in that spectral region."
http://www.hei.org/news/factshts/nihlfact.htm
It seems this thread has already convicted the old headset technology, and now thinks only a Bose active headset is acceptable, when a Bose depends on its ear cups, too.
Here is a paper that describes how well helmets and earplugs work to suppress noise, and how ANR does not change the noise above about 500 HZ (see Table I which has tons of studies together. It shows that ear muffs (headsets) and helmets work on your head):
http://www.aearo.com/pdf/hearingcons/limits2.pdf
Also, the hearing loss most of us get is high frequency, which is where the Bose does not work. Above about 500 Hz the active nose canceling is not at all effective. Bose used to say that on their web site, probably until they realized that they were losing sales that could be gained if they blurred the distinction between comfort (which they do provide) and protection (which is a very marginal product of the Bose technology). Here is a scientific paper that describes the fact that ANR does NOT protect you better than a good headset (but that the better communications and comfort are good to have.):
http://www.aearo.com/pdf/hearingcons/anr.pdf
Without someone who knows what he is talking about, this thread is wandering into strange territory!
Here is the Bose site, check out their manual, page 19 for example:
http://www.bose.com/controller;jsess...Br5LCs06T7R58J!103858704!-174109993?event=VIEW_PRODUCT_PAGE_EVENT&product=headsetx_hea dset_index&linksource=centernav_img_pilots&pageName=/index_2.jsp
Here is a web site that discusses hearing loss, showing that it usually occurs far above the range where Bose helps:
"When damage first occurs, it usually affects the part of the ear corresponding to the mid-frequency range of 3 to 5 kHz. On an audiogram, this type of hearing loss configuration is commonly referred to as a "noise notch." These frequencies correspond to the region where our consonant sounds are heard. A person with this type of hearing loss may have trouble understanding speech because the speech sounds "muffled"........ because the louder, lower frequency vowels are audible but the softer high frequency consonants are made even more difficult to hear, due to reduced hearing sensitivity in that spectral region."
http://www.hei.org/news/factshts/nihlfact.htm
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Hmmm, can't believe there aren't any takers yet!!!
The C+, ok machine I guess, still a 76 afterall. 2S1 engines, lots of jam, much more so than A or A+ (maybe A++ too?).
No. 1 weak link IMHO though is the DECU (Digital Engine Control Unit). Reason - Single Channel Digital Engine Control with good old fashioned cable backup for manual control, if required. This component is very capable of generating NO END of faults, most of which are minor in nature and pose more of an inconvenience than a genuine mechanical problem. Trouble is, even being an inconvenience means you need to call an engineer to clear the fault before you can go flying again. It can be a right royal pain in arse.
No. 2 weak spot is engine power assurance procedure and results of same. While things have gotten better from where they used to be, power margins can at times be right on the line. Assuming the on board calculation system fails to give a valid check, you are left with going to the chart and that can sometimes be entertaining. It's best if you make sure your pencil is not TOO sharp.
My two cents.
The C+, ok machine I guess, still a 76 afterall. 2S1 engines, lots of jam, much more so than A or A+ (maybe A++ too?).
No. 1 weak link IMHO though is the DECU (Digital Engine Control Unit). Reason - Single Channel Digital Engine Control with good old fashioned cable backup for manual control, if required. This component is very capable of generating NO END of faults, most of which are minor in nature and pose more of an inconvenience than a genuine mechanical problem. Trouble is, even being an inconvenience means you need to call an engineer to clear the fault before you can go flying again. It can be a right royal pain in arse.
No. 2 weak spot is engine power assurance procedure and results of same. While things have gotten better from where they used to be, power margins can at times be right on the line. Assuming the on board calculation system fails to give a valid check, you are left with going to the chart and that can sometimes be entertaining. It's best if you make sure your pencil is not TOO sharp.
My two cents.