Hard Core Category A?
Join Date: Aug 2004
Location: UK
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Helmet Fire said:
“The point was that the fuel dump is not effective on the rejected take off, nor after the TDP, but it is useful for the other 99.64% by giving you a much improved power margin for your subsequent actions.”
You brought up the issue of “brainspace” now read what I have been talking about in all of my post.
WE WANT TO REDUCE/ELIMINATE RTOD
The aircraft that I am familiar with that has fuel dump prohibits its use below 40Kts, regulations in the UK prohibit its use below 1000’, no gear operation during use and must be closed 1 minute before landing. As I said in a previous post, “If one is able to take off Cat A then, generally, one has Cat A enroute performance in most helicopter operations”. There will always be exceptions. “It would be useful to reduce weight for the OEI landing but the critical power phase is during T/O.” The fuel dump issue is a red herring to this discussion, period.
As previously stated, we are already flying in a 14 seater helicopter that has Cat A performance. Except, we only have 8 seats fitted! And still we find the performance marginal for onshore corporate/charter operations. What are you suggesting now…… a 22 seater for 6 pax? Again, as previously stated, the heavy helicopters are too big for most public use heli pads. We have already moved up one class in order to get some performance.
Nick, the points that I have been trying to get across are that the corporate customer, ‘he who actually pays for the machine’ has a perception, maybe carried from the fixed wing world, that a Cat A certification will ensure that if an engine should fail he and his family will be in no danger. My issue is that the performance on many machines with Cat A certification is so weak that we are not able to operate to full Cat A for most of the time. I am not talking about “Hard Core Cat A” at this time. Many times we have to operate to Cat A (Restricted). Most Corporate owners will not accept “limited exposure” as a concept, though that is what they have been exposed to, for a long time now, when operating to Cat A (R). I know that there are some operations that operate to Cat A all of the time but they have the luxury of site recce personnel, on site personnel and, normally, weeks of forward planning. For most operators this is not the case.
The UK Authority regulate for ‘full Cat A’ when operating in a congested area (a large proportion of England). The short field Cat A profiles for most helicopters still require a substantial reduction in payload and a RTOD. With temperatures regularly in the high 20’s during the summer, the penalty is even greater.
Now, I have no statistics to prove 2 engines are safer than one but I know that I couldn’t convince my customers that just 1 engine would be better! (It is a failing that most of us have if the number of twins is counted!) I haven’t been able to convince the CAA either! The manufacturers have not been convinced either or they would be promoting their medium singles a bit harder than they are!
Manufacturers, as suppliers to the industry, need to be aware of their customers needs. When asked, I will always say more power for my twin so that one day I can fly away OEI.
That day appears to be getting near, thankfully.
“The point was that the fuel dump is not effective on the rejected take off, nor after the TDP, but it is useful for the other 99.64% by giving you a much improved power margin for your subsequent actions.”
You brought up the issue of “brainspace” now read what I have been talking about in all of my post.
WE WANT TO REDUCE/ELIMINATE RTOD
The aircraft that I am familiar with that has fuel dump prohibits its use below 40Kts, regulations in the UK prohibit its use below 1000’, no gear operation during use and must be closed 1 minute before landing. As I said in a previous post, “If one is able to take off Cat A then, generally, one has Cat A enroute performance in most helicopter operations”. There will always be exceptions. “It would be useful to reduce weight for the OEI landing but the critical power phase is during T/O.” The fuel dump issue is a red herring to this discussion, period.
As previously stated, we are already flying in a 14 seater helicopter that has Cat A performance. Except, we only have 8 seats fitted! And still we find the performance marginal for onshore corporate/charter operations. What are you suggesting now…… a 22 seater for 6 pax? Again, as previously stated, the heavy helicopters are too big for most public use heli pads. We have already moved up one class in order to get some performance.
Nick, the points that I have been trying to get across are that the corporate customer, ‘he who actually pays for the machine’ has a perception, maybe carried from the fixed wing world, that a Cat A certification will ensure that if an engine should fail he and his family will be in no danger. My issue is that the performance on many machines with Cat A certification is so weak that we are not able to operate to full Cat A for most of the time. I am not talking about “Hard Core Cat A” at this time. Many times we have to operate to Cat A (Restricted). Most Corporate owners will not accept “limited exposure” as a concept, though that is what they have been exposed to, for a long time now, when operating to Cat A (R). I know that there are some operations that operate to Cat A all of the time but they have the luxury of site recce personnel, on site personnel and, normally, weeks of forward planning. For most operators this is not the case.
The UK Authority regulate for ‘full Cat A’ when operating in a congested area (a large proportion of England). The short field Cat A profiles for most helicopters still require a substantial reduction in payload and a RTOD. With temperatures regularly in the high 20’s during the summer, the penalty is even greater.
Now, I have no statistics to prove 2 engines are safer than one but I know that I couldn’t convince my customers that just 1 engine would be better! (It is a failing that most of us have if the number of twins is counted!) I haven’t been able to convince the CAA either! The manufacturers have not been convinced either or they would be promoting their medium singles a bit harder than they are!
Manufacturers, as suppliers to the industry, need to be aware of their customers needs. When asked, I will always say more power for my twin so that one day I can fly away OEI.
That day appears to be getting near, thankfully.
FLI,
you just dont get the risk management/risk exposure bits do you?
Or risk exposure V cost.
And I think you missed the brainspace bit too.
Oh and the bit about using fuel dump in an emergency. You know you are not permitted to crash either!
Repeat: if you want NO exposure you DO have 2 current options:
1. Reduce payload.
2. Buy a more powerful machine.
Do you really land at places in a heavy S76 that you could not squeeze a lightly loaded (reduced downwash) S61, S70, or maybe even B412 or AB139? Really? You land your corprate S76 in such tight areas that a few extra feet make all the difference?
I believe that if you have already moved up one class for your performace reasons then you have really not conducted a thorough analysis of requirements if you are already having problems. Or, if you customer changed their requirements - they must be aware of the extra cost.
Have you considered two light twins lightly loaded, ie 109s or EC135s?
you just dont get the risk management/risk exposure bits do you?
Or risk exposure V cost.
And I think you missed the brainspace bit too.
Oh and the bit about using fuel dump in an emergency. You know you are not permitted to crash either!
Repeat: if you want NO exposure you DO have 2 current options:
1. Reduce payload.
2. Buy a more powerful machine.
Do you really land at places in a heavy S76 that you could not squeeze a lightly loaded (reduced downwash) S61, S70, or maybe even B412 or AB139? Really? You land your corprate S76 in such tight areas that a few extra feet make all the difference?
I believe that if you have already moved up one class for your performace reasons then you have really not conducted a thorough analysis of requirements if you are already having problems. Or, if you customer changed their requirements - they must be aware of the extra cost.
Have you considered two light twins lightly loaded, ie 109s or EC135s?
Join Date: Aug 2004
Location: UK
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Helmet Fire,
I don’t know why I am even replying to you!
If you read my post you will know that I certainly know what risk management/risk exposure/cost are all about.
What you appear to have no knowledge on is VIP Corporate/ Charter operations within UK, Europe and many other parts of the world. The types of customers and the regulations make life very difficult in this environment. Your cr*p about fuel dump for onshore VIP ops just highlights your complete lack of knowledge in this arena.
The type of clients that I am referring to do not buy old second hand aircraft!
They want new or nearly new. Up until now, there has been no aircraft that comprehensively covers all the conditions that I have been referring to. The Sikorsky 76B came close but was dis-continued.
Augusta has now produced an aircraft that will replace it. Watch how corporate clients trade in their 76’s, 155’s, 365's and 412’s to buy the AB139?
Then tell me there isn’t a market for a powerful twin!!
P.S. Not only do you know nothing about corporate aviation you don’t even know how to spell it! Same goes for performance! (See your previous post)
I don’t know why I am even replying to you!
If you read my post you will know that I certainly know what risk management/risk exposure/cost are all about.
What you appear to have no knowledge on is VIP Corporate/ Charter operations within UK, Europe and many other parts of the world. The types of customers and the regulations make life very difficult in this environment. Your cr*p about fuel dump for onshore VIP ops just highlights your complete lack of knowledge in this arena.
The type of clients that I am referring to do not buy old second hand aircraft!
They want new or nearly new. Up until now, there has been no aircraft that comprehensively covers all the conditions that I have been referring to. The Sikorsky 76B came close but was dis-continued.
Augusta has now produced an aircraft that will replace it. Watch how corporate clients trade in their 76’s, 155’s, 365's and 412’s to buy the AB139?
Then tell me there isn’t a market for a powerful twin!!
P.S. Not only do you know nothing about corporate aviation you don’t even know how to spell it! Same goes for performance! (See your previous post)
I hope that readers of this thread are finding it as informative as those of us who have been prepared to post.
Nick, in a previous email warned us to take care with the simple questions about Cat A or not Cat A; I might add my warning to his and use that as justification to clarify the usage of the term Category A. From a close reading of the definition(s) posted on the first page of this thread, it can be seen that the term is restricted to the landing and take-off phases - there is no such thing as en-route Cat A. FAR 29.67 - 'Climb: One Engine Inoperative (OEI)' is confined to establishing the requirement for first (at 200ft) and second (at 1000ft) segment climb requirements and, subsequent to revision 39, the production of data to establish the climb (or descent) data in the complete operating envelope. Whilst on the subject, there is also no such thing as Cat A Restricted (there is Group A - the UK performance standard, and Group A restricted - which was a less precise form of PC2).
It is therefore (quite rightly) left to operating regulations to stipulate what the en-route climb performance should be. In JAR-OPS 3 that requirement (simply stated) is for a 50ft/min climb performance at an altitude which gives obstacles clearance. Drift down is permitted as is fuel dump:
The subtext for fuel dumping was discussed at great length before the words were chosen - in practice it is not as simple or as useful as it first appears; for offshore, if we refer to the previous discussion on one-way-fuel v beach-fuel - with one-way-fuel there is no possibility of use and with beach-fuel there is no need; there are specific onshore cases where fuel dump might be useful but when they exist, they need careful planning.
In FARs in the overwater case, the VFR requirement for en-route climb performance - 50ft /min at 1,000ft - is alleviated if floats are fitted FAR 135,183(d); and for the IFR case: onshore - requires 50ft/min at the MEA or 5,000ft, whichever is the higher; offshore - requires 50ft/min at the MEA or 1,500ft MSL, whichever is the higher.
Performance Classes give a much richer operational vocabulary particularly PC2 which describes exactly the points that Nick and others are making about a limited period when engine failure accountability is not provided on take-off and landing. The terms are written objectively and permit any number of methods of compliance.
Whether PC1 is used is a matter of policy for a number of interested parties: society will decide whether ‘exposure’ is permitted in a congested hostile environment (congested area) and customers (oil companies - and some cases like Norway - States) will decide whether zero exposure (PC1 or PC2e) is the standard for operations to helidecks. Provided that a large enough customer base exists for operations in PC1, the manufacturers will provide the equipment and the appropriate procedures. That these zero exposure options come at a cost is not in doubt; for some customers/States the prospect of not specifying zero exposure when it is possible (and it is) and then suffering a failure leading to death or injury is not a justifiable option.
If PC1 is not used (or is too costly in terms of loss of payload/range), PC2 provides the ability to establish the cost of exposure in a number of currencies. When the calculations are performed, the key elements will be the probability of failure, the consequence of failure and most important of all, whether the subsequent calculation is within the safety target chosen. The calculation for each aircraft type can be standard as the maximum exposure is, as Mars stated above, finite.
Nick, in a previous email warned us to take care with the simple questions about Cat A or not Cat A; I might add my warning to his and use that as justification to clarify the usage of the term Category A. From a close reading of the definition(s) posted on the first page of this thread, it can be seen that the term is restricted to the landing and take-off phases - there is no such thing as en-route Cat A. FAR 29.67 - 'Climb: One Engine Inoperative (OEI)' is confined to establishing the requirement for first (at 200ft) and second (at 1000ft) segment climb requirements and, subsequent to revision 39, the production of data to establish the climb (or descent) data in the complete operating envelope. Whilst on the subject, there is also no such thing as Cat A Restricted (there is Group A - the UK performance standard, and Group A restricted - which was a less precise form of PC2).
It is therefore (quite rightly) left to operating regulations to stipulate what the en-route climb performance should be. In JAR-OPS 3 that requirement (simply stated) is for a 50ft/min climb performance at an altitude which gives obstacles clearance. Drift down is permitted as is fuel dump:
Fuel jettison is planned to take place only to extent consistent with reaching the heliport with the required fuel reserves and using a safe procedure.
In FARs in the overwater case, the VFR requirement for en-route climb performance - 50ft /min at 1,000ft - is alleviated if floats are fitted FAR 135,183(d); and for the IFR case: onshore - requires 50ft/min at the MEA or 5,000ft, whichever is the higher; offshore - requires 50ft/min at the MEA or 1,500ft MSL, whichever is the higher.
Performance Classes give a much richer operational vocabulary particularly PC2 which describes exactly the points that Nick and others are making about a limited period when engine failure accountability is not provided on take-off and landing. The terms are written objectively and permit any number of methods of compliance.
Whether PC1 is used is a matter of policy for a number of interested parties: society will decide whether ‘exposure’ is permitted in a congested hostile environment (congested area) and customers (oil companies - and some cases like Norway - States) will decide whether zero exposure (PC1 or PC2e) is the standard for operations to helidecks. Provided that a large enough customer base exists for operations in PC1, the manufacturers will provide the equipment and the appropriate procedures. That these zero exposure options come at a cost is not in doubt; for some customers/States the prospect of not specifying zero exposure when it is possible (and it is) and then suffering a failure leading to death or injury is not a justifiable option.
If PC1 is not used (or is too costly in terms of loss of payload/range), PC2 provides the ability to establish the cost of exposure in a number of currencies. When the calculations are performed, the key elements will be the probability of failure, the consequence of failure and most important of all, whether the subsequent calculation is within the safety target chosen. The calculation for each aircraft type can be standard as the maximum exposure is, as Mars stated above, finite.
Last edited by JimL; 17th Aug 2004 at 14:31.
meow.
I hope I spelled it write.
Oh, and the AB139 - so you are going to buy a more powerful machine after all that?
Helmut.
JimL: Here in Oz we have a slightly different enroute climb requirement OEI, and that is dependant upon category (airwork, charter, & VFR or IFR, etc) but it is essentially the same aim. You are right about the fuel dump not being so straight forward - it requires forethought and calculation prior to enroute use for the reasons you allude to: though I would contend that it is not rocket science. But at the take off and landing areas, it is very straight forward, simple to use, and of benefit. I also agree that it's use is of smaller benefit for offshore ops - but it is still of benefit. Overland, there are occaisions when our drift down requirement prevents me carrying preferred fuel loads in my current EMS job, let alone the take off and landing phases. And in the charter situation, it would greatly benefit our higher DA operations by allowing more fuel on take offs.
BTW, Does you fuel dump plan regulation actually say "the" heliport, or any heliport? In other words, is a diversion acceptable for fuel dumping purposes? Can "heliport" be met by a field, road or paddock, or does it mean a permanent helicopter landing site?
I hope I spelled it write.
Oh, and the AB139 - so you are going to buy a more powerful machine after all that?
Helmut.
JimL: Here in Oz we have a slightly different enroute climb requirement OEI, and that is dependant upon category (airwork, charter, & VFR or IFR, etc) but it is essentially the same aim. You are right about the fuel dump not being so straight forward - it requires forethought and calculation prior to enroute use for the reasons you allude to: though I would contend that it is not rocket science. But at the take off and landing areas, it is very straight forward, simple to use, and of benefit. I also agree that it's use is of smaller benefit for offshore ops - but it is still of benefit. Overland, there are occaisions when our drift down requirement prevents me carrying preferred fuel loads in my current EMS job, let alone the take off and landing phases. And in the charter situation, it would greatly benefit our higher DA operations by allowing more fuel on take offs.
BTW, Does you fuel dump plan regulation actually say "the" heliport, or any heliport? In other words, is a diversion acceptable for fuel dumping purposes? Can "heliport" be met by a field, road or paddock, or does it mean a permanent helicopter landing site?
Last edited by helmet fire; 17th Aug 2004 at 21:22.
Helmet Fire,
The wording was specifically chosen so as not to constrain the operator; however, if use of fuel dump is planned (in the sense that it is known that an engine failure at some point will result in a lack of obstacle clearance) the resulting diversion must be know in order to ensure sufficient fuel reserves - this can include en-route alternates. The rules that have been quoted are, as with Australian regulations, aimed only at Commercial Air Transport (CAT). (T'was a time when fuel dump was used in the S61 to permit CAT B take-off from Aberdeen so that benefit could be taken for the overland portion; en-route climb performance had to be obtained before crossing the coast.)
You might have to accept that, for the purpose of this discussion (which is about take-off and landing performance), fuel dump has no real relevance.
None of what we are discussing is rocket science but there are a number of strongly held views that are somewhat related to the societal ethic of the State of Operation. For my own selfish motives, this thread does provide a platform to broadcast and discuss a number of concepts that we in Europe have been developing for a number of years.
Informed wisdom has it that the AB139 will only have one Category A procedure, a vertical profile with a (variable) TDP of 10ft or higher if an obstacle has to be cleared in the continued take-off; this will not require a Rejected Take-Off Distance (RTOD) larger than the pad (providing that visual cues can be maintained). One benefit will be the reduction of training (and training accidents) required for operations in PC1, and unconstrained PC1 offshore (until someone wishes to grow the aircraft).
The wording was specifically chosen so as not to constrain the operator; however, if use of fuel dump is planned (in the sense that it is known that an engine failure at some point will result in a lack of obstacle clearance) the resulting diversion must be know in order to ensure sufficient fuel reserves - this can include en-route alternates. The rules that have been quoted are, as with Australian regulations, aimed only at Commercial Air Transport (CAT). (T'was a time when fuel dump was used in the S61 to permit CAT B take-off from Aberdeen so that benefit could be taken for the overland portion; en-route climb performance had to be obtained before crossing the coast.)
You might have to accept that, for the purpose of this discussion (which is about take-off and landing performance), fuel dump has no real relevance.
None of what we are discussing is rocket science but there are a number of strongly held views that are somewhat related to the societal ethic of the State of Operation. For my own selfish motives, this thread does provide a platform to broadcast and discuss a number of concepts that we in Europe have been developing for a number of years.
Informed wisdom has it that the AB139 will only have one Category A procedure, a vertical profile with a (variable) TDP of 10ft or higher if an obstacle has to be cleared in the continued take-off; this will not require a Rejected Take-Off Distance (RTOD) larger than the pad (providing that visual cues can be maintained). One benefit will be the reduction of training (and training accidents) required for operations in PC1, and unconstrained PC1 offshore (until someone wishes to grow the aircraft).
Last edited by JimL; 17th Aug 2004 at 14:29.
Thanks JimL.
Could you touch on the last question I asked in relation to a heliport please?
Please keep at it with your "own selfish motives" so we can all continue to peer into the European intent of some of these rules and procedures. Thanks for the patience - it makes good reading.
Could you touch on the last question I asked in relation to a heliport please?
Please keep at it with your "own selfish motives" so we can all continue to peer into the European intent of some of these rules and procedures. Thanks for the patience - it makes good reading.
Helmet Fire,
It was that question I was alluding to in the first paragraph of my response; yes you could have a fuel dump alternate which could be any landing area qualifying as a heliport.
Note that this definition comes directly from Annex 6 Part III and should therefore be usable in any Contracting State - unless it is 'masked' by a local requirement. It has been adopted and used in JARs.
It was that question I was alluding to in the first paragraph of my response; yes you could have a fuel dump alternate which could be any landing area qualifying as a heliport.
Heliport. An aerodrome or a defined area of land, water or a structure used or intended to be used wholly or in part for the arrival, departure and surface movement of helicopters.
Last edited by JimL; 18th Aug 2004 at 07:31.
I think the reason the fuel dump issue is becoming talked about at slightly crossed purposes is that the rules in Australia are different than Europe regarding max take off weight. I do not have the regulations to hand, but know from discussion with Australian colleagues, that because of the high temperatures routinely encountered it is not viable to operate to what we would consider normal PC1 or PC2 criteria. Allowable take off weight is more like a 0 rate of climb OEI weight or similar; is that right helmet? This may therefore be above the en-route weight.
Therefore, in that instance it may be of benefit to dump fuel on departure in the event of a failure. However, if operating to PC2 or PC1, the second segment climb requirement will be more limiting than the en-route weight restriction, unless there is a very restrictive MSA along the track, and so it is not normally of any benefit to have fuel dumping as an option.
The reference to the S-61 ops from Aberdeen is historical and relates to a regulatory regime long past that allowed Group B take off weights as long as fuel dump could ensure Group A en-route weight. This is a similar situation to the current Australian regulatory position, I think but stand to be corrected!
None of which is of any consolation to FLI and his passengers as they wrap themselves round a tree!
Helmet et al, don't be so quick to jump down others throats; generally if somone is quoting a sensible set of facts and concerns, they are probably grounded in some reality! I could go into some detail about client expectations in a new aircraft and how they relate to the actual delivered product, but it would be totally innapropriate in this context. However, the result highlights many of the concerns discussed above.
Therefore, in that instance it may be of benefit to dump fuel on departure in the event of a failure. However, if operating to PC2 or PC1, the second segment climb requirement will be more limiting than the en-route weight restriction, unless there is a very restrictive MSA along the track, and so it is not normally of any benefit to have fuel dumping as an option.
The reference to the S-61 ops from Aberdeen is historical and relates to a regulatory regime long past that allowed Group B take off weights as long as fuel dump could ensure Group A en-route weight. This is a similar situation to the current Australian regulatory position, I think but stand to be corrected!
None of which is of any consolation to FLI and his passengers as they wrap themselves round a tree!
Helmet et al, don't be so quick to jump down others throats; generally if somone is quoting a sensible set of facts and concerns, they are probably grounded in some reality! I could go into some detail about client expectations in a new aircraft and how they relate to the actual delivered product, but it would be totally innapropriate in this context. However, the result highlights many of the concerns discussed above.
Join Date: Aug 2004
Location: UK
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
JimL,
My apologies for mixing up the various operating standards. I switched to Cat A instead of Group A so that a larger audience would understand what I was referring to.
Of course, Cat A (Restricted) should have been referred to as Group A (Restricted). Or PC2.
The reference to Cat A enroute was used, simplistically, to indicate sufficient single engine power to sustain level flight clear of all obstacles whilst flying to a landing site after segment 2 on the Group A T/O.
Thank you, for the very precise wording and explanations on PC1 and PC2.
My apologies for mixing up the various operating standards. I switched to Cat A instead of Group A so that a larger audience would understand what I was referring to.
Of course, Cat A (Restricted) should have been referred to as Group A (Restricted). Or PC2.
The reference to Cat A enroute was used, simplistically, to indicate sufficient single engine power to sustain level flight clear of all obstacles whilst flying to a landing site after segment 2 on the Group A T/O.
Thank you, for the very precise wording and explanations on PC1 and PC2.
Last edited by FLI; 18th Aug 2004 at 12:43.
Join Date: Dec 2001
Location: Philadelphia PA
Age: 73
Posts: 1,835
Likes: 0
Received 2 Likes
on
2 Posts
Regarding fuel dump - you can't use it to reduce weight until after you've got Vtoss and the initial climb going. Check Part 29 and the Advisory Circular - it's a secondary control, and as such can't be used for performance purposes for determining all the necessary things until after you're safely climbing.
Also probably not a good idea to be trying to do it in what will be a pretty busy time anyway.
Also probably not a good idea to be trying to do it in what will be a pretty busy time anyway.
Join Date: Jun 2003
Location: Off the Planet
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Even though this thread has slowed, it is not clear that we should be letting this subject go. Whilst there is a lull in proceedings and to allow time for all to draw a second breath here for your amusement and delectation are a couple of quotes. A bottle of champagne to the first guru who can tell us where they appeared and the year:
Concerns relating to powerplants appeared to top the lists of all the users. A true one-engine-inoperative capability was referred to repeatedly and in a variety of ways. The operators were unanimous in their endorsement of twin engine helicopters, but less happy with available single engine performance. Ideally, an out-of-ground-effect hover capability with one-engine-inoperative was desired.
FAA is encouraged by the increases in power-to-weight which have resulted from technological changes over the last 15 years in transport category rotorcraft, and it is hoped that increased technology will ultimately lead to full category A performance capability for these transport category designs.
Join Date: Jun 2003
Location: Off the Planet
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Well done GLSNightPilot! The document can be found at the following location
http://www.airweb.faa.gov/Regulatory...2568f600663576
The text that was quoted was indeed in the Final Rule text of Amdt. 29-21, Eff. 3/2/83.
Interestingly, NPRM 80-25 was issued on 12/15/80 and contained a proposal that would have required Category A for all helicopters certificated with 10 or more seats:
In the event, the proposal to meet an operational requirement of PC1 for helicopters with 10 or more seats was not carried and, with one exception, the applicability of FAR 29.1 was downgraded to a requirement to meet PC2. The exception; helicopters with Maximum Gross Weight greater than 20,000 pounds and certificated with more than 9 passenger seats, for which the requirement remained… hang on! Doesn’t the S92 fit into that category? In Europe, FAR 29.1 appears to be seen only as a certification requirement.
The results of the FAA deliberations can be seen in a modified form in the JAR-OPS applicability for the Performance Classes:
well, considering that statement was probably drafted between 1980 and 1982, it is difficult to estimate what time scale ultimately was meant to encompass (did they consider that we would still be discussing this 24 years later?). Isn’t it interesting though that, for a number of good reasons, the FAR 27 twins have arrived at that destination already but, as they are limited to 9 passenger seats, were never intended even to make the journey.
My contention would be that we have also arrived for the FAR 29 helicopters that were designed after the application of this NPRM; that this cannot be done for all sites, under all operating conditions and at the maximum mass, is a feature of the flexibility of the helicopter not one of lack of intent or engineering skills. It is therefore for operational regulations to establish the conditions under which any necessary gap might be bridged. Risk Assessment provides the tools to establish what that gap might be under a particular circumstance, and whether to use PC2 (with exposure) to bridge that gap - or reduce payload and operate in PC1. For offshore operations, we now have the added tool of performance modelling to virtually reduce that performance gap to nil - operating in accordance with PC2e but without compromising the pilot’s discretion.
Every day it is possible to make the last minute tweaks - the introduction of the CT7-8A will add another 5% to the available performance with the same geometry and without modification to the airframe; how, by clever engineering and by using different materials to improve the 30 second rating by about 140hp. This appears to be something for nothing as the 30 second rating should never be used and does not have any operational cost.
http://www.airweb.faa.gov/Regulatory...2568f600663576
The text that was quoted was indeed in the Final Rule text of Amdt. 29-21, Eff. 3/2/83.
Interestingly, NPRM 80-25 was issued on 12/15/80 and contained a proposal that would have required Category A for all helicopters certificated with 10 or more seats:
Rotorcraft are projected to be carrying more and more passengers in business, commuter, and air carrier roles. This proposal would provide a clear and consistent 10 passenger division point for continued takeoff capability with engine failure for all fixed or rotary wing aircraft. The weight penalty to rotor craft for operation under the improved safety level of category A is parallel to that already experienced by fixed wing aircraft operating at the 10 passenger level and above. The tradeoffs between performance and weight are essentially the same in fixed and rotary wing aircraft. This proposal upgrades rotorcraft performance standards to those of their fixed wing counterparts. The economic and safety considerations of the continued takeoff philosophy for 10 or more passengers are discussed in considerable detail in NPRMS 67-11 (32 FR 5698; April 7, 1967) and 68-37 (34 FR 210; January 7, 1969) and in the preamble to Amendment 135-18 (35 FR 10098; June 19, 1970). Pertinent rulemaking philosophy and FAA's response to industry comments contained therein apply equally to this notice. In spite of dire predictions to the contrary, the current fixed wing air taxi industry is thriving under the 10 passenger
The results of the FAA deliberations can be seen in a modified form in the JAR-OPS applicability for the Performance Classes:
FAA is encouraged by the increases in power-to-weight which have resulted from technological changes over the last 15 years in transport category rotorcraft, and it is hoped that increased technology will ultimately lead to full category A performance capability for these transport category designs.
My contention would be that we have also arrived for the FAR 29 helicopters that were designed after the application of this NPRM; that this cannot be done for all sites, under all operating conditions and at the maximum mass, is a feature of the flexibility of the helicopter not one of lack of intent or engineering skills. It is therefore for operational regulations to establish the conditions under which any necessary gap might be bridged. Risk Assessment provides the tools to establish what that gap might be under a particular circumstance, and whether to use PC2 (with exposure) to bridge that gap - or reduce payload and operate in PC1. For offshore operations, we now have the added tool of performance modelling to virtually reduce that performance gap to nil - operating in accordance with PC2e but without compromising the pilot’s discretion.
Every day it is possible to make the last minute tweaks - the introduction of the CT7-8A will add another 5% to the available performance with the same geometry and without modification to the airframe; how, by clever engineering and by using different materials to improve the 30 second rating by about 140hp. This appears to be something for nothing as the 30 second rating should never be used and does not have any operational cost.
Nick opened this thread describing the dilemma:
It has been the belief of a number of us for some considerable time that performance, as with all aviation matters, is not an ‘either or’ choice. What we should be debating is the management of safety - which is not measured in absolute terms but expressed as safety targets.
That two views are expressed already indicates that any manufacturer who wishes to maximise its market, has to position its product so that it can meet both aspirations. The one that cannot be satisfied is that which demands PC1 for all sizes of sites at all density altitudes.
Recent developments have increased the number of risk management tools; performance modelling has shown that, for offshore operations, the margin of exposure (due to performance) can be reduced to a theoretical zero. Why the conditional statement? Because those of us who have been in offshore operations for a number of years will know that, on occasions, the environmental conditions and the obstacle environment, prevents us from flying the optimum profile.
For the uninitiated, there are three (theoretical) subdivisions of PC2 that an operator can take advantage of; these range from nil exposure (without using Category A procedures) to limited exposure - and are as follows (not in that order):
What we have to hope for (because we have no information on which to base any assumptions) is that Eurocopter will take note of the enlightened attitude of Sikorsky, and also position their products (the EC225, EC155 and AS332L2) to meet both sets of aspirations.
One side says that the engine is prone enough to failure that it is wise to design a helicopter that has complete coverage of its flight path so that engine failure can occur without probability of a mishap. Let's call this hover to hover or "full Cat A".
The other side says that a limited exposure where an engine failure can result in a hard landing is acceptable, as long as it can be shown that the probability of an engine failure in that exposure time is as slight as the other kinds of failures that can happen to a helicopter. Let’s call that "limited exposure."
The other side says that a limited exposure where an engine failure can result in a hard landing is acceptable, as long as it can be shown that the probability of an engine failure in that exposure time is as slight as the other kinds of failures that can happen to a helicopter. Let’s call that "limited exposure."
That two views are expressed already indicates that any manufacturer who wishes to maximise its market, has to position its product so that it can meet both aspirations. The one that cannot be satisfied is that which demands PC1 for all sizes of sites at all density altitudes.
Recent developments have increased the number of risk management tools; performance modelling has shown that, for offshore operations, the margin of exposure (due to performance) can be reduced to a theoretical zero. Why the conditional statement? Because those of us who have been in offshore operations for a number of years will know that, on occasions, the environmental conditions and the obstacle environment, prevents us from flying the optimum profile.
For the uninitiated, there are three (theoretical) subdivisions of PC2 that an operator can take advantage of; these range from nil exposure (without using Category A procedures) to limited exposure - and are as follows (not in that order):
What we have to hope for (because we have no information on which to base any assumptions) is that Eurocopter will take note of the enlightened attitude of Sikorsky, and also position their products (the EC225, EC155 and AS332L2) to meet both sets of aspirations.
Last edited by JimL; 21st Aug 2004 at 07:28.
Join Date: Aug 2004
Location: UK
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
JimL,
I am a bit confused with your explanaition on the performance on the S92.
This is an article that I found on the H-92 written last year at the Paris Air show.
I quote just part of the article.
“The civil S-92 aircraft on which the H-92 Superhawk is based has already achieved U.S. certification. Standard S-92 safety features that will be found in the H-92 Superhawk include flaw tolerant components, multiple redundant control systems, bird strike protection, high-intensity radiated field protection and category A (class 1) performance, which allows pilots to continue safe flight in the event of an engine failure at any point in flight”.
Full article can be found here:
http://www.ainonline.com/Publication...d2h92pg14.html
The article implies that the S92 will have, so called, “Hard Core”/ ”Full Cat A”. Is this correct? Are there substantial payload reductions or DA restrictions to achieve this?
I am a bit confused with your explanaition on the performance on the S92.
This is an article that I found on the H-92 written last year at the Paris Air show.
I quote just part of the article.
“The civil S-92 aircraft on which the H-92 Superhawk is based has already achieved U.S. certification. Standard S-92 safety features that will be found in the H-92 Superhawk include flaw tolerant components, multiple redundant control systems, bird strike protection, high-intensity radiated field protection and category A (class 1) performance, which allows pilots to continue safe flight in the event of an engine failure at any point in flight”.
Full article can be found here:
http://www.ainonline.com/Publication...d2h92pg14.html
The article implies that the S92 will have, so called, “Hard Core”/ ”Full Cat A”. Is this correct? Are there substantial payload reductions or DA restrictions to achieve this?
Thread Starter
Join Date: Apr 2003
Location: USA
Age: 75
Posts: 3,012
Likes: 0
Received 0 Likes
on
0 Posts
JimL,
Thanks for clarifying the case with your last post. Note that the performance for Cat A is not a sharp decision, yes or no, as you say. I believe few helicopters will come out where the maximum weight allows full Cat A, because the ability to recoup this extra power as payload for other operations will be so compelling that the aircraft will have two or three operating procedures, one for hard Cat A, and one for lesser OEI but a higher MGW and much better payload/range. Thus one design will serve several possible customer bases.
This debate has unfortunately not driven into the kind of discussion I had hoped, because it became a vote on hard Cat A yes or no, and not a discussion of safer or less safe.
It seems that so many vocal regulators and some customers (FLI out there?) speak as though the solution to helicopter operational safety concerns is more power. This is in spite of the data, and of the real hazards. If the debate does not move off this as a flip switch, yes/no, helicopter safety will suffer for another generation, I believe.
I am struck too at the inability of we who make the machines to express the cost to a design to meet these requirements - the plots I provided that showed a massive penalty for hard Cat A were virtually ignored by all, as if they were not part of the discussion, perhaps because I phrased the discussion so poorly.
So, here is a possibly new way to state the question:
Given that a helicopter will be designed to lose 25% of its range (or the equivilent payload) and this penalty assigned to safety concerns, what concerns should be addressed? A possible sample:
Hover to hover full Instrument procedures to heliports in rural and urban areas, independant of airplane operations
Pilot visionics, where the pilot sees the world through a see-through virtual reality device, with FLIR and CGI mixed so that night/instrument is as if he were in a simulator, and VFR like rules are applied to all traffic.
Hard terrain avoidance, where the machine is not capable of being driven into the ground except as a controlled landing. This includes brown out and zero light available circumstances.
Maintenance free operation for a full year, during which only pilot pre-flight inspection is required, and during which all maintenance activities are diagnosed by the aircraft
Tolerance to accept common corrosion, damage and mishandling so that no unsafe condition is developed for the year.
Ability to Fly in any icing, rain, or wind condition without loss of control.
Fly with the noise signature of a common large car, so that ground observers note no objectionable noise, even in rural areas.
As a helicopter R&D engineer, I can state that all the above are not just possible, they can be certified within 10 years. And none will cost half of what hard Cat A does cost to the design. As someone who wishes the best for all of us (we are one big family in a way) I simply cannot understand why we are not asking for these things to be legislated!
And for FLI, your questions about the Cat A performance of the S-92 have already been answered in this thread. It is my belief that the S-92 is the most capable hard Cat A platform now available, with more payload, range, speed from a hard Cat A operation off a rig or from ground level than any helicopter. However, this thread has nothing to do with any specific helo, in spite of your wish to make my general comments somehow specific to any given helicopter's capabilities. You might just be one of those fellows who just never gets the message, sadly.
Thanks for clarifying the case with your last post. Note that the performance for Cat A is not a sharp decision, yes or no, as you say. I believe few helicopters will come out where the maximum weight allows full Cat A, because the ability to recoup this extra power as payload for other operations will be so compelling that the aircraft will have two or three operating procedures, one for hard Cat A, and one for lesser OEI but a higher MGW and much better payload/range. Thus one design will serve several possible customer bases.
This debate has unfortunately not driven into the kind of discussion I had hoped, because it became a vote on hard Cat A yes or no, and not a discussion of safer or less safe.
It seems that so many vocal regulators and some customers (FLI out there?) speak as though the solution to helicopter operational safety concerns is more power. This is in spite of the data, and of the real hazards. If the debate does not move off this as a flip switch, yes/no, helicopter safety will suffer for another generation, I believe.
I am struck too at the inability of we who make the machines to express the cost to a design to meet these requirements - the plots I provided that showed a massive penalty for hard Cat A were virtually ignored by all, as if they were not part of the discussion, perhaps because I phrased the discussion so poorly.
So, here is a possibly new way to state the question:
Given that a helicopter will be designed to lose 25% of its range (or the equivilent payload) and this penalty assigned to safety concerns, what concerns should be addressed? A possible sample:
Hover to hover full Instrument procedures to heliports in rural and urban areas, independant of airplane operations
Pilot visionics, where the pilot sees the world through a see-through virtual reality device, with FLIR and CGI mixed so that night/instrument is as if he were in a simulator, and VFR like rules are applied to all traffic.
Hard terrain avoidance, where the machine is not capable of being driven into the ground except as a controlled landing. This includes brown out and zero light available circumstances.
Maintenance free operation for a full year, during which only pilot pre-flight inspection is required, and during which all maintenance activities are diagnosed by the aircraft
Tolerance to accept common corrosion, damage and mishandling so that no unsafe condition is developed for the year.
Ability to Fly in any icing, rain, or wind condition without loss of control.
Fly with the noise signature of a common large car, so that ground observers note no objectionable noise, even in rural areas.
As a helicopter R&D engineer, I can state that all the above are not just possible, they can be certified within 10 years. And none will cost half of what hard Cat A does cost to the design. As someone who wishes the best for all of us (we are one big family in a way) I simply cannot understand why we are not asking for these things to be legislated!
And for FLI, your questions about the Cat A performance of the S-92 have already been answered in this thread. It is my belief that the S-92 is the most capable hard Cat A platform now available, with more payload, range, speed from a hard Cat A operation off a rig or from ground level than any helicopter. However, this thread has nothing to do with any specific helo, in spite of your wish to make my general comments somehow specific to any given helicopter's capabilities. You might just be one of those fellows who just never gets the message, sadly.
Well said Nick - for the third or fourth time this thread.
Is it that the operators are really not savvy enough to buy a machine that is capable of flexibility - or is it that the customer really hates to think (or cannot understand) that there is an empty seat next to them in order to reduce their risk exposure? Or can they in no way be educated about this?
I note that FLI said they had adjusted the seating of the aircraft to 6 in order to achieve greater power margin, so why not look at your operating envelope, pick the max DA and range your customer will make you operate to - couple it with the exposure profile they desire - then fit the max number of seats that will be able to be filled? Hey presto: you have achieved what you want: a "hardcore Cat A" machine without penalising other buyers who can accept different risk exposure.
Or maybe the answer to "the customer is always right" thing when education fails, is to give them what they want. How about Sikorsky produce a VIP S76 with only four seats in the back so that it can be considered to have the best PC1 rating known to man, and then a utility version for those who want to adapt to flexible performance/exposure/cost profiles depandant upon missions?
Nick: lets not divert spending into areas that can resolve higher risks to helicopter operations, lets produce machines that never require performance planning.
Is it that the operators are really not savvy enough to buy a machine that is capable of flexibility - or is it that the customer really hates to think (or cannot understand) that there is an empty seat next to them in order to reduce their risk exposure? Or can they in no way be educated about this?
I note that FLI said they had adjusted the seating of the aircraft to 6 in order to achieve greater power margin, so why not look at your operating envelope, pick the max DA and range your customer will make you operate to - couple it with the exposure profile they desire - then fit the max number of seats that will be able to be filled? Hey presto: you have achieved what you want: a "hardcore Cat A" machine without penalising other buyers who can accept different risk exposure.
Or maybe the answer to "the customer is always right" thing when education fails, is to give them what they want. How about Sikorsky produce a VIP S76 with only four seats in the back so that it can be considered to have the best PC1 rating known to man, and then a utility version for those who want to adapt to flexible performance/exposure/cost profiles depandant upon missions?
Nick: lets not divert spending into areas that can resolve higher risks to helicopter operations, lets produce machines that never require performance planning.
Join Date: Apr 2002
Location: Can
Posts: 172
Likes: 0
Received 0 Likes
on
0 Posts
Legislation, particularly operations within congested areas, requires full Cat A. On many of the helicopters today that is nigh on impossible without a very substantial reduction in payload. Perhaps, instead, we should be lobbying for a relaxation of the rules based on the industry statistics? Maybe, even, fly medium singles as they appear to answer a lot of the problems that the manufactures have in providing what we want?
Regulations for Cat A capabilities are in place. The regulatory bodies feel that it IS a safety concern. (Third party liability.....can't have helicopters landing on people in the street below when the aircraft misses the rooftop helipad OEI.)
The problem as I see it is that companies may be ignoring the fact. Hesitant to bring their customers up to date on the Cat A issue for fear of lost contracts or closed flight departments. Regulatory bodies do not enforce the regulations that they have put in place until, as Nick says, once in 55 years, we have an accident.
Whether we feel that money could be better spent elsewhere is a great topic for discussion. This topic really should have been discussed between operators, manufacturers and regulatory bodies before the regulations were put into effect. Now the guy caught in the middle is the pilot. Surprise surprise.
For the record Nick, I think we could spend our money more wisely than having full Cat A capability but the regulatory body in this country doesn't seem to agree.
Cheers
Last edited by Xnr; 25th Aug 2004 at 14:36.