Sikorsky S-92: From Design to Operations
212 - OK I roll over you are correct - in-flight shutdowns don't count for PC2 as they are under the pilot's control and yes of course I was just stirring it. However the reliability rate (in which I include IFSDs) so far does seem poor compared to other types.
Out of interest does the UK N Sea operator in fact rigorously operate it to PC2e offshore?
Nick - you are correct too, though its not without good reason!
HC
Out of interest does the UK N Sea operator in fact rigorously operate it to PC2e offshore?
Nick - you are correct too, though its not without good reason!
HC
Norsk Helicopter S92 lands single engine after engine fire warning
It is reported that a S92 lands single engine at Lista, Norway today at about 1530 following an in flight shut down after an engine fire warning.
The outbound flight to the Ekofisk field flight turned around and landed at the nearest onshore airport after about 1 hour SE return flight.
The outbound flight to the Ekofisk field flight turned around and landed at the nearest onshore airport after about 1 hour SE return flight.
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Norwegian S-92 Returned to shore after fire in engine.
Not too many weeks since one of the Norwegian operators had one of their s-92's fly 90 min on one engine, and today another s-92 had to shut down one due to engine-fire. They chose to return to the closest landbased airport and landed safely there.
Article is in Norwegian.
http://www.bt.no/trafikk/article311207.ece
Article is in Norwegian.
http://www.bt.no/trafikk/article311207.ece
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Power
"But the point remains that all those extra dollars could be spent actually making our ops safer, not reducing an already negligible risk exposure to almost zero."
are your statistics also applicable to S92?
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Of course! In fact the power levels of the S92 and many other offshore helos are precisely what I think are right - Cat A from a rig but without the tremendous overkill that ends up sacrificing range and payload, as is the case with the AW139, where the 21000 lb helicopter is trapped in a 15000 lb certification.
The S92 carries 19 pax in ISA+10 zero wind, 50 foot dropdown to about 300 Nm with IFR reserves. As you seem to misunderstand bpaggi, there is too little power, the right amount of power and too much power. Yes, you can have too much power, just look at the payload range data to see what I mean.
The S92 carries 19 pax in ISA+10 zero wind, 50 foot dropdown to about 300 Nm with IFR reserves. As you seem to misunderstand bpaggi, there is too little power, the right amount of power and too much power. Yes, you can have too much power, just look at the payload range data to see what I mean.
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Ah!!!!!!!! Yes........too much power..grrrrrreat
Nick
The market will decide I believe. As an unreconstructed petrolhead I have to say that we would be in a dreadful state if the world was populated only with Ford Mondeo 80 Horse Power clones. Don't you think the world would be a poorer place without a 7 litre Mustang or Aston Martin or those blessed Italian monsters that are unfortunately designed on the R22 model and wont allow 6ft 4" guys like me to get in the darn things.
Power is a bit like sex, when you complain of too much you really have me worried. I don't know whether to be embarassed, angry or just jealous. One thing is for sure, I really appreciate being able to shop in a market that offers more than just a technocrat approach to our world. No offence meant to anybody, especially NL, so please don't take that the wrong way.
G
The market will decide I believe. As an unreconstructed petrolhead I have to say that we would be in a dreadful state if the world was populated only with Ford Mondeo 80 Horse Power clones. Don't you think the world would be a poorer place without a 7 litre Mustang or Aston Martin or those blessed Italian monsters that are unfortunately designed on the R22 model and wont allow 6ft 4" guys like me to get in the darn things.
Power is a bit like sex, when you complain of too much you really have me worried. I don't know whether to be embarassed, angry or just jealous. One thing is for sure, I really appreciate being able to shop in a market that offers more than just a technocrat approach to our world. No offence meant to anybody, especially NL, so please don't take that the wrong way.
G
Last edited by Geoffersincornwall; 2nd Nov 2006 at 05:15.
bpaggi
you were actually quoting me and not Nick, however, I am glad you brought this up. It proves the point exactly doesn't it?
Also, check the 76 down in the GOM thread. Onlky 2 POB on a 76 but no amount of CAT A helped those guys.
Maybe a collective trim tiggered rad alt hold function would have......
you were actually quoting me and not Nick, however, I am glad you brought this up. It proves the point exactly doesn't it?
Also, check the 76 down in the GOM thread. Onlky 2 POB on a 76 but no amount of CAT A helped those guys.
Maybe a collective trim tiggered rad alt hold function would have......
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Sorry helmet fire, I was trying to make the point on the AW139 thread discussion I had with Nick Lappos.
I perfectly know that engine failures are not the most probable cause of accidents but the probability is not almost nil.
Anyway, I think the concept of two much power is relative.
As far as Nick is concerned, the right power is the amount that allows the kind of operations the S92 (or many other offshore helo) can afford. But what about all the rigs where the prevailing weather conditions for most of the year are at ISA+20 to ISA+35?
Are these rigs penalized and therefore do not deserve a Cat A operations in order to allow a decent payload or range?
Following Nick's thoughts i wonder why S92 is operated under Cat A? Should not be more economic to allow better performance despite the "almost nil" probability of an engine failure?
I do think the AW139 is a terrific helicopter that grants such kind of operations in every rig in the world regardless of the OAT and in order to have that you'll probabily pay a little more than other helos.
Having said that, I'm glad tha everybody in the S92 is safe back home.
Happy landings
I perfectly know that engine failures are not the most probable cause of accidents but the probability is not almost nil.
Anyway, I think the concept of two much power is relative.
As far as Nick is concerned, the right power is the amount that allows the kind of operations the S92 (or many other offshore helo) can afford. But what about all the rigs where the prevailing weather conditions for most of the year are at ISA+20 to ISA+35?
Are these rigs penalized and therefore do not deserve a Cat A operations in order to allow a decent payload or range?
Following Nick's thoughts i wonder why S92 is operated under Cat A? Should not be more economic to allow better performance despite the "almost nil" probability of an engine failure?
I do think the AW139 is a terrific helicopter that grants such kind of operations in every rig in the world regardless of the OAT and in order to have that you'll probabily pay a little more than other helos.
Having said that, I'm glad tha everybody in the S92 is safe back home.
Happy landings
False fire warning
Although sombody startet a separate tread on the fire warning incident yesterday, I still believe it belongs here with the other experiences, good and bad, with the S92.
A press statement from the operator confirms that this was no fire, i.e. a false fire warning. It indicates that once the fault was corrected and the firebottles replaced, the aircraft returned to the main base at Sola/Stavanger.
It also states that the single engine portion of the flight back to shore was 1 hour 44 min.
A press statement from the operator confirms that this was no fire, i.e. a false fire warning. It indicates that once the fault was corrected and the firebottles replaced, the aircraft returned to the main base at Sola/Stavanger.
It also states that the single engine portion of the flight back to shore was 1 hour 44 min.
Surely the most important issue here is not why there appears to be a higher than expected in-flight shut down rate, but that having lost an engine the crews were able to fly the helicopter and its passengers safely to a location often several hours away without any further incident on single engine performance.
Is this not what you would want from any modern helicopter whoever the manufacturer?
Is this not what you would want from any modern helicopter whoever the manufacturer?
Thanks bpaggi, I was also involved in the AW 139 thread.
That is the crux of the discussion; who gets penalised? Should the high DA rigs be penalised for the low DA ones, or the low DA for the high?
The advantage of using the low DA rig as the benchmark is that all operations can be run economically, but advantaging the high DA requires too much excess power for the low DA and thus creates a loser.
Look at it this way: 10 pax CAT A power to a high DA rig can be achieved by a 10 pax capacity full CAT A machine, or by a 15 pax capacity limited CAT A machine carrying only 10 pax. When that same machine is now used on low DA rigs, the 15 pax machine now carries 15, but the 10 pax can still only carry 10 pax! And to achieve the 10 pax high DA CAT A, both machines would need comparable engine and drivetrain weights and fuel consumptions wouldn't they? When they move to the low DA rig, the 10 pax machine is carrying that higher consumption and drivetrain weight without getting any return, but the 15 pax machine gets to carry 5 more pigs.
So if you work in an area with large DA variations, it pays much larger dividends to use the 15 pax limited CAT A machine doesn't it? And everyone else who gets the 15 pax machine and can accept the 0.17% exposure can save money on the high DA days too.
That saving should be then invested in anti CFIT measures rather than full CAT A over all rig types - especially given CFIT is the more prevalent of the dangers.
Spot on. It is fantastic and I certainly dont wish for anything else for my christmas present this year!!!! But pretty soon, they will be expanding the weight upwards and out of the full CAT A capability and it will also become an economical one across risk profiles. Same way the A109E is now not a "Full CAT A" machine post 3000kg upgrade - but you can still operate it full CAT A if you want to restrict it to 2850kg. At least Eagle 86 told me so!
Are these [high DA] rigs penalized and therefore do not deserve a Cat A operations in order to allow a decent payload or range?
The advantage of using the low DA rig as the benchmark is that all operations can be run economically, but advantaging the high DA requires too much excess power for the low DA and thus creates a loser.
Look at it this way: 10 pax CAT A power to a high DA rig can be achieved by a 10 pax capacity full CAT A machine, or by a 15 pax capacity limited CAT A machine carrying only 10 pax. When that same machine is now used on low DA rigs, the 15 pax machine now carries 15, but the 10 pax can still only carry 10 pax! And to achieve the 10 pax high DA CAT A, both machines would need comparable engine and drivetrain weights and fuel consumptions wouldn't they? When they move to the low DA rig, the 10 pax machine is carrying that higher consumption and drivetrain weight without getting any return, but the 15 pax machine gets to carry 5 more pigs.
So if you work in an area with large DA variations, it pays much larger dividends to use the 15 pax limited CAT A machine doesn't it? And everyone else who gets the 15 pax machine and can accept the 0.17% exposure can save money on the high DA days too.
That saving should be then invested in anti CFIT measures rather than full CAT A over all rig types - especially given CFIT is the more prevalent of the dangers.
I do think the AW139 is a terrific helicopter
Hilife
Surely all twins are able to fly you home on one engine if loaded correctly? Its just that I would rather fly a helicopter that doesn't routinely put this to the test.
helmet fire
- just picking up on your last point, for protection against flying into the sea I agree that some sort of TAWS is a very good idea.
But I am not a fan of EGPWS for offshore ops because its derived from fixed-wing and currently doesn't really do the job well, but is nevertheless relatively expensive. For a fraction of the price you can have AVAD linked to your radalt which has served well in Europe for many years. The problem is that since the USA didn't invent AVAD, they prefer to pretend it doesn't exist and create a new and very complicated way of achieving the same thing (though not as well).
EGPWS is bandied around as being the best thing since whatever only by people who don't understand how it actually works (and NL)
Only for operations over land does EGPWS have any advantage over AVAD.
HC
Surely all twins are able to fly you home on one engine if loaded correctly? Its just that I would rather fly a helicopter that doesn't routinely put this to the test.
helmet fire
- just picking up on your last point, for protection against flying into the sea I agree that some sort of TAWS is a very good idea.
But I am not a fan of EGPWS for offshore ops because its derived from fixed-wing and currently doesn't really do the job well, but is nevertheless relatively expensive. For a fraction of the price you can have AVAD linked to your radalt which has served well in Europe for many years. The problem is that since the USA didn't invent AVAD, they prefer to pretend it doesn't exist and create a new and very complicated way of achieving the same thing (though not as well).
EGPWS is bandied around as being the best thing since whatever only by people who don't understand how it actually works (and NL)
Only for operations over land does EGPWS have any advantage over AVAD.
HC
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HC
The 'loaded correctly' is a good point as its perfectly possible to drop a performance class (in JAR OPS-3 terms) by poor planning.
PHI managed this with a Bolkow in 2003. A certain customer had wanted PC2 and selected a twin for their contract, yet it was so heavily loaded it drifted down and into the sea after an engine oil seal leaked tiggering an shutdown of one engine i.e. PC3 but twice the chance of a shutdown.
EGPWS has been marketed for the offshore community with stunning disconnection from logic. What next? Will the salesmen have a go at the onshore community and sell floats for flying over the Sahara? The campaign should be for a cheap but effective AVAD on EVERY offshore helicopter NOW!
The 'loaded correctly' is a good point as its perfectly possible to drop a performance class (in JAR OPS-3 terms) by poor planning.
PHI managed this with a Bolkow in 2003. A certain customer had wanted PC2 and selected a twin for their contract, yet it was so heavily loaded it drifted down and into the sea after an engine oil seal leaked tiggering an shutdown of one engine i.e. PC3 but twice the chance of a shutdown.
EGPWS has been marketed for the offshore community with stunning disconnection from logic. What next? Will the salesmen have a go at the onshore community and sell floats for flying over the Sahara? The campaign should be for a cheap but effective AVAD on EVERY offshore helicopter NOW!
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helicomparitor proves yet again that ignorance is still rampant in the region between his ears, and unfortunately sox6 eats hc's porrage.
An EGPWS is not just a map terrain model, in spite of hc's errant beliefs. It has ALL of the functions of AVAD, and additionally provides many other modes. It is very effective over water in many ways, as its protection schemes include over 30 different sets of rules that protect over water operations. I would't expect hc to bother to learn this before he makes his foolish recommendations. I also wouldn't expect hc to know that I was the developer of the helicopter EGPWS, working in conjunction with the FAA and the Allied-Honeywell folks who know more about this game than hc will ever even conceive. Nor would I expect sox6 to know that the EGPWS functions in helicopter mode are exclusive to helos, and the FW mode functions are germain to the forward flight modes that helos share.
A sample of the modes:
Mode 1 Excessive sink rate
Mode 2 Excessive terrain closure rate (also to rig/obstructions)
Mode 3 Sink after takeoff
Mode 4 Too close to terrain/water
Mode 5 Excessive deviation below glide slope
Mode 6 Autorotation callouts (altitude, bank)
From what I have read of the PHI accident (I have read a detailed personal account by the pilot) that accident would have been entirely announced by the EGPWS.
Here is the SB that added avad callouts to the EGPWS:
http://www.egpws.com/engineering_sup...2-0714-121.pdf
I guess hc also believes that no offshore helo could possibly fly over land, thus his erudite decision that no offshore helo needs over land protection. As stunning a conclusion as his decision that window size is more important than crashworthiness or crack prevention of critical parts! Attaboy, hc, you've done it again!
An EGPWS is not just a map terrain model, in spite of hc's errant beliefs. It has ALL of the functions of AVAD, and additionally provides many other modes. It is very effective over water in many ways, as its protection schemes include over 30 different sets of rules that protect over water operations. I would't expect hc to bother to learn this before he makes his foolish recommendations. I also wouldn't expect hc to know that I was the developer of the helicopter EGPWS, working in conjunction with the FAA and the Allied-Honeywell folks who know more about this game than hc will ever even conceive. Nor would I expect sox6 to know that the EGPWS functions in helicopter mode are exclusive to helos, and the FW mode functions are germain to the forward flight modes that helos share.
A sample of the modes:
Mode 1 Excessive sink rate
Mode 2 Excessive terrain closure rate (also to rig/obstructions)
Mode 3 Sink after takeoff
Mode 4 Too close to terrain/water
Mode 5 Excessive deviation below glide slope
Mode 6 Autorotation callouts (altitude, bank)
From what I have read of the PHI accident (I have read a detailed personal account by the pilot) that accident would have been entirely announced by the EGPWS.
Here is the SB that added avad callouts to the EGPWS:
http://www.egpws.com/engineering_sup...2-0714-121.pdf
I guess hc also believes that no offshore helo could possibly fly over land, thus his erudite decision that no offshore helo needs over land protection. As stunning a conclusion as his decision that window size is more important than crashworthiness or crack prevention of critical parts! Attaboy, hc, you've done it again!
Last edited by NickLappos; 4th Nov 2006 at 15:01.
Sox - hear hear!
Nick's post is interesting in that he confirms my suspicions that he helped develop the helicopter version of the EGPWS (the MkXXII) by tweaking the software from the fixed-wing version (which is why in my post I had to exclude NL in the group of people who didn't know how it works).
But Nick you did a very poor job and if it were me I certainly wouldn't want anyone to know I was responsible, or at least that I did some of the test flying (I doubt you single-handedly wrote the software though I am sure you would like to imply that). You also picked the wrong guy to try to bull**** because I am very familiar with all the modes you mention.
Nick is correct that, excluding the E part of EGPWS which relates to the terrain database, there are a number of basic GPWS modes. He is incorrect when he says various other things including that it has all the functions of AVAD.
With version 24 of the software, to which the SB he links to refers, the Mk XXII became compliant with the letter of the JAR-OPS 3.660 which is the requirement for radalt voice alerting. When originally introduced into Europe on the S92 (pre v24) it did not, though there was a work-around which was not fail safe but which the JOEB reluctanly had to accept or ground the aircraft. But even with v24, AVAD is not well replicated. Yes there is now the uncancellable 100' callout but there is no satisfactory substitute for "check height".
There are a couple of Mode 6 callouts that could be considered but neither the "altitude" nor the "minimums" callouts are acceptable - one only works with the gear up and the other only gives one warning - you will not get a second warning unless you either climb 200' or land, so its by no means safe for use with ARAs etc.
AVAD uses attenson tones to attact attention to the messages. These attensons were the result of substantial research carried out in the UK into voice messages - but of course not invented in the USA so not in EGPWS
These is the primary reasons why one of the larger oil companies has decided to delay implementation of EGPWS until the software is improved, and why Eurocopter's offering has to revert to the basic aircraft tones when you descend throught he bugged radalt height.
So now lets look at some of these wonderful modes that Nick mentions. He denies they are hang-overs from fixed wing but I will let you be the judge of that:
Mode 1 - this must be really useful because its permanently inhibited on the S92! Its "excessive sinkrate" but to trigger it you have to enter a sinkrate / height zone bordered by a line joining 10' and 900'/min, 20' and 1200'/min, 500' and 3000'/min. So you could be at 1199'/min descent rate and 21' - one second from impact - and not get a warning. Very useful! Its clearly aimed at not giving a warning to large fixed wing who come hurtling down the ILS to roundout height.
Mode 2 - this is inhibited when the terrain awareness data has high integrity, which is likely to be most of the time so not much use then. Even if it is working its sub-mode 2A (gear up in the cruise) has a high trigger threshold eg 1300'/min at 30' as does mode 2B (takeoff and landing - gear down) eg 3625'/min at 300' and 2375'/min at 100' and its not operative below 100'.
Mode 3 - descent after takeoff. This actually might have some value for night rig takeoffs, though nothing a PNF monitoring doesn't give you. And unfortunately it doesn't become active until you reach 50kts IAS or put the gear up.
Mode 4 seems to be more to do with high speed level flight with the gear up ( mode 4A) or gear down (4B). The former seems to be a reminder to put the gear down and the latter to give you a ticking-off for that fast low pass! Its boundaries are 120kts at 100' reducing to 80kts at 10'. Protection against inadvertant entry into these zones is better given by AVAD, but I suppose if you are stuck with EGPWS this mode might help a bit.
Mode 5 monitors ILS approaches and lets you know you are below glideslope. We carry PNF for that and with modern fully coupled aircraft it doesn't have much value. It may cause nuisance warnings as you might be doing a visual approach with the ILS tuned in. Yes there is an inhibit button but that's another cockpit action required.
And lastly (thank God) Mode 6 which does various callouts - the two I mentioned earlier as poor AVAD sustitutes plus bank angle callout, though with modern quadruplexed-autopilot aircraft I am not sure of the usefullness of this. And there is one for tailrotor strike (excessive pitch attitude at low level). Sounds good until you consider the elevated helideck landing case - as you come in with the tail below deck level the radalt is still seeing the sea etc so no warning until it goes crunch!
So overall I would rather have AVAD!
Nick does point out the blindingly obvious - ie some offshore helicopters fly overland for a bit. This is of course true though in the case of the N Sea, not much and the land is pretty flat. But I can see that the E bit of EGPWS would have some value for some operations - but have we considered the following:
Why would we need the E- bit? On an IFR flight we should of course be above MESA or whatever but sometimes mistakes are made so yes, EGPWS gives protection there without a doubt. On a VFR flight its for when we go inadvertant IMC. But I wonder how tempting it will be to continue a VFR flight you should otherwise have given up on cosy in the knowledge that the EGPWS will keep you right. Will EGPWS bring out the cowboy in us and lead to increased accidents? Only time will tell.
I forgot to mention that yipee the terrain database will show us the oil platforms. But this will definitely suck us into disaster as it will not show semi-subs etc - ie only part of the picture and that renders it dangerous in my opinion.
Well I think that's enough for one post - looking forward to Nick's blusterous response!
HC
ps can't resist a final dig when NL mentions "crack prevention of critical parts". I guess he had temporarily forgotten that, apart from the numerous (non life-threatening) aircrame cracks the 92 experiences, there has recently been a withdrawl from service of a number of S92 gearboxes due to their casings cracking! Now that's what I would call a critical part!
Nick's post is interesting in that he confirms my suspicions that he helped develop the helicopter version of the EGPWS (the MkXXII) by tweaking the software from the fixed-wing version (which is why in my post I had to exclude NL in the group of people who didn't know how it works).
But Nick you did a very poor job and if it were me I certainly wouldn't want anyone to know I was responsible, or at least that I did some of the test flying (I doubt you single-handedly wrote the software though I am sure you would like to imply that). You also picked the wrong guy to try to bull**** because I am very familiar with all the modes you mention.
Nick is correct that, excluding the E part of EGPWS which relates to the terrain database, there are a number of basic GPWS modes. He is incorrect when he says various other things including that it has all the functions of AVAD.
With version 24 of the software, to which the SB he links to refers, the Mk XXII became compliant with the letter of the JAR-OPS 3.660 which is the requirement for radalt voice alerting. When originally introduced into Europe on the S92 (pre v24) it did not, though there was a work-around which was not fail safe but which the JOEB reluctanly had to accept or ground the aircraft. But even with v24, AVAD is not well replicated. Yes there is now the uncancellable 100' callout but there is no satisfactory substitute for "check height".
There are a couple of Mode 6 callouts that could be considered but neither the "altitude" nor the "minimums" callouts are acceptable - one only works with the gear up and the other only gives one warning - you will not get a second warning unless you either climb 200' or land, so its by no means safe for use with ARAs etc.
AVAD uses attenson tones to attact attention to the messages. These attensons were the result of substantial research carried out in the UK into voice messages - but of course not invented in the USA so not in EGPWS
These is the primary reasons why one of the larger oil companies has decided to delay implementation of EGPWS until the software is improved, and why Eurocopter's offering has to revert to the basic aircraft tones when you descend throught he bugged radalt height.
So now lets look at some of these wonderful modes that Nick mentions. He denies they are hang-overs from fixed wing but I will let you be the judge of that:
Mode 1 - this must be really useful because its permanently inhibited on the S92! Its "excessive sinkrate" but to trigger it you have to enter a sinkrate / height zone bordered by a line joining 10' and 900'/min, 20' and 1200'/min, 500' and 3000'/min. So you could be at 1199'/min descent rate and 21' - one second from impact - and not get a warning. Very useful! Its clearly aimed at not giving a warning to large fixed wing who come hurtling down the ILS to roundout height.
Mode 2 - this is inhibited when the terrain awareness data has high integrity, which is likely to be most of the time so not much use then. Even if it is working its sub-mode 2A (gear up in the cruise) has a high trigger threshold eg 1300'/min at 30' as does mode 2B (takeoff and landing - gear down) eg 3625'/min at 300' and 2375'/min at 100' and its not operative below 100'.
Mode 3 - descent after takeoff. This actually might have some value for night rig takeoffs, though nothing a PNF monitoring doesn't give you. And unfortunately it doesn't become active until you reach 50kts IAS or put the gear up.
Mode 4 seems to be more to do with high speed level flight with the gear up ( mode 4A) or gear down (4B). The former seems to be a reminder to put the gear down and the latter to give you a ticking-off for that fast low pass! Its boundaries are 120kts at 100' reducing to 80kts at 10'. Protection against inadvertant entry into these zones is better given by AVAD, but I suppose if you are stuck with EGPWS this mode might help a bit.
Mode 5 monitors ILS approaches and lets you know you are below glideslope. We carry PNF for that and with modern fully coupled aircraft it doesn't have much value. It may cause nuisance warnings as you might be doing a visual approach with the ILS tuned in. Yes there is an inhibit button but that's another cockpit action required.
And lastly (thank God) Mode 6 which does various callouts - the two I mentioned earlier as poor AVAD sustitutes plus bank angle callout, though with modern quadruplexed-autopilot aircraft I am not sure of the usefullness of this. And there is one for tailrotor strike (excessive pitch attitude at low level). Sounds good until you consider the elevated helideck landing case - as you come in with the tail below deck level the radalt is still seeing the sea etc so no warning until it goes crunch!
So overall I would rather have AVAD!
Nick does point out the blindingly obvious - ie some offshore helicopters fly overland for a bit. This is of course true though in the case of the N Sea, not much and the land is pretty flat. But I can see that the E bit of EGPWS would have some value for some operations - but have we considered the following:
Why would we need the E- bit? On an IFR flight we should of course be above MESA or whatever but sometimes mistakes are made so yes, EGPWS gives protection there without a doubt. On a VFR flight its for when we go inadvertant IMC. But I wonder how tempting it will be to continue a VFR flight you should otherwise have given up on cosy in the knowledge that the EGPWS will keep you right. Will EGPWS bring out the cowboy in us and lead to increased accidents? Only time will tell.
I forgot to mention that yipee the terrain database will show us the oil platforms. But this will definitely suck us into disaster as it will not show semi-subs etc - ie only part of the picture and that renders it dangerous in my opinion.
Well I think that's enough for one post - looking forward to Nick's blusterous response!
HC
ps can't resist a final dig when NL mentions "crack prevention of critical parts". I guess he had temporarily forgotten that, apart from the numerous (non life-threatening) aircrame cracks the 92 experiences, there has recently been a withdrawl from service of a number of S92 gearboxes due to their casings cracking! Now that's what I would call a critical part!
Last edited by HeliComparator; 4th Nov 2006 at 21:50.
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Now, now HC, the replacement life of those gearboxes are almost up to the overhaul life of the Rolls-Royce (Blackburn) Nimbus engine. Such is progress.
Now Nick, the tail box is subject to critcal part control is it not....?
Now Nick, the tail box is subject to critcal part control is it not....?
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HC you must be very disappointed now that there is "One Bristow" in the words of your Chairman, and he has decided to buy 2 S92's. Must be a bitter pill for such a frog-lover to swallow!
PS I hear your Super Pumas are being sold off, too bad, huh?
PS I hear your Super Pumas are being sold off, too bad, huh?
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Mike - Thanks, I needed that!
HC, your silly quibbling is just like that drivel you published about window size where you thought the escape windows were more important than the basic safety features of the helo. You slicing and dicing of the EGPWS features- things you have little understanding of - is another example of how your blinded neo-technical judgement is so very off-base. While 40% of helo accidents are caused by impacting water or earth, you quibble about the only system that is certified to prevent them. Typical, you must light candles to the lost Empire, where all those little red leather log books kept many people with clerk's minds like yours very, very busy.
You are a fitting example of why a foreign company swallowed your company, and why a good friend and helicoptering genius, Alan Bristow, must be rolling in his grave when he reads your crap.
HC, your silly quibbling is just like that drivel you published about window size where you thought the escape windows were more important than the basic safety features of the helo. You slicing and dicing of the EGPWS features- things you have little understanding of - is another example of how your blinded neo-technical judgement is so very off-base. While 40% of helo accidents are caused by impacting water or earth, you quibble about the only system that is certified to prevent them. Typical, you must light candles to the lost Empire, where all those little red leather log books kept many people with clerk's minds like yours very, very busy.
You are a fitting example of why a foreign company swallowed your company, and why a good friend and helicoptering genius, Alan Bristow, must be rolling in his grave when he reads your crap.