True Cat A Performance

[Xnr]

Happy New Year

Just was sitting at work wondering which helicopter types are certified for True Cat A Performance.

By that I mean a helo that is "certified" to take off vertically from a helipad, lose an stove, and either safely reject to the helipad below or safely fly away.

Also it must be "certified" to approach that same helipad, lose a stove on the approach, and either safely fly away or land zero speed (no roll).

[Helinut]

Most twins will fulfil that requirement, the only difference will be that most will not do what you want at MAUM - or have I missed something??

[Xnr]

I feel that most twins are only "certified" for a rolling landing Cat A.

Not much good if your helipad dimensions are 100'x 100' or smaller.

[Nick Lappos]

One can argue the real necessity for the capability, but most Part 29 twins have ground level heliport or elevated helideck Cat A procedures, usually as suppliments to the basic RFM. These procedures by definition allow no ground roll. They are generally at considerable reduction in gross weight because the performance penalty for the Cat A landback is severe.
The next generation of helos will meet JAR Ops 3, which will get them much closer to max gross weight with helideck Cat A capability. The S-92 will perform a Cat A takeoff from an elevated helideck with a full passenger load and at zero wind at 35 degrees C with enough gas to fly about 300 NM with IFR reserves.

[donut king]

Happy New Year to all!!!

I don't think it's fair to say our present choice of twin powered helo's cannot meet Cat A performance.

I would suggest that the engines alone cannot provide the juice for true Cat A.

Give me an Allison/ Arriel/ Pratt/ or whatever, in my '76, with 1500shp per side and then we'll talk.

Maybe we should be challenging the engine manufacturers instead of the a/c builders????

As a famous man said,
" We need more power Scotty"
J.T Kirk

D.K

[Nick Lappos]

Donut King,

Were it only that easy! Note that the transmission is filled by the engine for moderate climates, so a bigger engine wouldn't help, at least until you get to altitude.

[idle stop]

Sorry, but it's a bit simplistic just to want more pwerful engines. There are a lot of powerplants out there that will produce more than rated power. Generally, the other important limitation is the power that can be transmitted by the main gearbox, particularly when the power input is assymetric: ie, one engine input no power and the other megawatts of it!
So the answer is to build beefier gearboxes, you say. But hang on! The whole darn airframe just got heavier, so we're back where we started.
On a more optimistic note, if a powerplant may deliver more than rated power in a tight spot this may perhaps be at the cost of an engine and gearbox after the successful forced landing. Still less expensive than crumpling the whole aircraft.
Going back to the original point, and reinforcing what Nick says, when aircraft are certificated for Cat A (or equivalent) the test pilots and engineers will develop the best profiles (capable of being flown by an average pilot) for different take-off and landing circumstances and these will be certificated, subject to the associated and defined WAT limits. Stick to the graphs and the profiles and you should be OK. There are quite a few twins around that can operate to CAT A conditions at MAUW from/into restricted areas using the approved techniques on more days than not, in temperate UK-type climates.

[donut king]

Nick L. and Idle Stop,

Yes, I was intentionally being simplistic!

Twin a/c we have are good strong machines. Designed well and tested extensively.

It's very easy to find the weak links in the machine if we just concentrate on specific performance criteria...ie.. perfect Cat A flight at all flight envelopes and weights.

Sure, you guys can put extremely powerful engines in the a/c, but at what cost?...... no payload and minimum fuel!!

However, I do see a time when some 12year old, Playstation addicted, geeky kid, turns out to design lighter, more powerful, smaller engines.

You guys, as engineers, must acknowledge that is possible in the future.

[212man]

The other consideration when looking at more powerful engines is that when in twin mode they will be a long way off their design point and consequently very inefficient. The result is horrendous fuel consumption. Look at the 76-B (sorry Nick, no offence!). In some areas that isn't a problem, but it certainly is in others.

[SASless]

212man......

Must be the EC-155 you drive must fit your description of the perfect machine....engines that get the best fuel consumption on two.....although probably not the best on one donk. How long is your takeoff distance required now....still on the order of 1700 feet for the Shell Machines?

[Thomas coupling]

EC135 helipad to MAUM @ISA+5 @SL.

[Steve76]

Who cares really?
When was the last time anyone needed Cat A performance?

Solution to perceived problem: new engines with enhanced durability and reliability. We are flying the sky with 1960's engine design.

[Jack S.]

Regarding new engines....
I read a realy interesting article in Flying magazine the other day.
One of it's contributing writers was going on about the Eclipse and how the project wont work because the project is based on the design of brand new engines. The writer concludes that the design wont work, hence the aircraft will never fly.
I for one hope that the company will provide it's new engine with all the capabilities it promises. It's time engine makers take a step into the future and start making smaller, lighter and better engines.
Idiots like the writer in the article that think it will never happen, should realize that a 100 years ago we weren't even flying and that it's always up to some pioneers to raise the bar.
If the new engine design works, you know every manufacturer will start making a similar model, but now it's easier for them to say it's impossible to make one and just keep on selling the same old 1960's stuff.
Just my opinion though, I could be wrong.
Jack S.

[Xnr]

Steve76

The problem comes when our "friends" at Transport Canada restrict helipads to machines capable Cat A performance.

Can you legally land there with the machine you fly at the weight you carry?

The effect of this restriction is severe and most cannot comply.

[What Limits]

New does not necessarily mean better reliability or durability. Have flown around 2000 hours in various machines with the RR/Allison 250 and never had a failure, but a few precautionary shutdowns for Chips.

Steve76

Do you mean Cat A performance OEI or AEO? If you are doing HEMS then you often need the AEO performance for helipad (elevated) and sub-helipad (exemption) approaches and departures.

Shouldn't we really be talking Cat I, II, III ?

Can of worms opened.......

[Jack S.]

Xnr,

why do you consider the requirement for a 'true cat A' from TC as a problem?
Wouldn't it be nice if you could fly a slightly more potent machine, thus increasing the safety aspect?
I understand it would be hard for any company to upgrade an entire fleet, but I think it will be just a matter of time before TC starts following JAR Op's and starts imposing higher limits.
Yes it will lead to a lot of complaining, but I'm sure the crews actually flying the machines will feel pretty good about it.
Flying to an elevated rooftop less than 100' square, in an A model at +30C weather with 5 on board, some cargo and fuel is just not as safe as it should be. Now you can train all you want for the 'unlikely event' of an engine failure in these conditions, but know that the day an engine quits on the final stage of your approach to a pad in such conditions, you better be right on the numbers, as there will be no margin of error.
Of course some of the aviation gods will dispute this because this will A: never happen to them and B: they can deal with such emergencies at any time.
Of course that's just my opinion, I could be wrong.

[Shawn Coyle]

xnr:
I think I know a bit of the background to this problem as I used to work in TC Aircraft Certification and discussed this a lot with the ops people, and the heliport design folks.
The issue was safe operation in and out of some heliports that weren't ideal. The solution was to either require Cat A, or demonstrated performance to get you into or out of the heliport if an engine failed.
This was the first time that TC had required Cat A in any operations, so I'm not surprised that there were some questions and comments.
But it was done with a lot of discussion and consideration. Any other problems, you can contact me off-line if you want.

[Nick Lappos]

Jack S,
The issues that determine the mix of airframe properties are not as simply stated as "Do you want Cat A or don't you". Given a free choice, I'd take Cat A from cradle to grave, fuel for 1500 NM, and a blonde copilot, thanks. Life, and helicopter design, don't work that way, unfortunately.

The basic problen is that you ask a loaded question - "why do you consider the requirement for a 'true cat A' from TC as a problem? " This question assumes that you just check off a property and it is delivered to you, like Amazon.com without a charge. Not so.

How about if you ask the question the way a designer sees it?

"Which would you rather have, hover to hover Cat A, or a helicopter that costs 10% less?" Or "Which would you rather have, hover to hover Cat A, or a helicopter with 50 NM more range" Or "Which would you rather have, hover to hover Cat A, or a helicopter with full GPS coupled autopilot to a hover"

The cost of taking a regular Cat A twin helicopter to a zero ground roll on a single engine is very real, and not easily hidden. Basically, the second engine is along for the ride, mostly. For a 10,000 pound twin, I would guess the weight penalty would be about 300 pounds of empty weight ("Which would you rather have, hover to hover Cat A, or an extra fare-paying passenger?"). The cost of engine power is the steepest bill we pay, withg the engine, the transmission, shafting and fuel all tolling up bigtime. It would be hard to imagine the cost of the hover to hover Cat A being less than 10% of the purchase price of the aircraft.

All this also must be weighed against the need, since we have lots of data to show that the few seconds of exposure during takeoff and landing are almost insignificant in terms of measurable safety improvement. ("Which would you rather have, hover to hover Cat A, or a full enhanced ground proximity warning device?")

[SASless]

Nick,

In yer opening you suggest a liberal leftist "cradle to grave" Cat A welfare system....but then digress to suggest a more conservative "cost vs risk " scenario. Perhaps you are hanging around the oil company management types a bit too much? If you see the advantage of the full Cat A, much as the S-92 will provide (per your earlier post), why the contrary statements. I know you will hit me up with the 0.0000008 chance of an engine failure number....as in earlier posts....but why remind us of the wonderful improvement in performance the 92 brings over previous designs if that in fact becomes an expensive overkill situation for commercial operators? Per chance, you Sikorsky types are really designing a new airframe for military applications and will do a transfer of technology bit at some time in the near future and provide the Coast Guard or some other operation an improved airframe for their mission?

[Xnr]

Sorry boys...I have to agree with Nick.

If you want true Cat A then you have to be able to do everything on one donkey.....how about two 1300 shp donks for an S76A......she'd be a little hard on fuel I think.

The problem in Canada is some of our helipads are restricted to helicopters that are not yet off the drawing board. Pilots are thinking that their Cat A birds are certified to land there.....IMHO they are not.

Until the operators buy the new generation aircraft just close these restricted helipads.....that's about what the restriction accomplishes.

[Nick Lappos]

Sasless and Xnr,
I really don't advocate a full Cat A capability, personally, but I also recognize that we are here to give you what you want to buy.
The S-92 has it because that's what the JAR Ops operating rules will require. It comes at a cost, of course.

[widgeon]

Well at least you have a blonde flight test engineer Nick, give Phil a poke from me next time you see him.

[GLSNightPilot]

Nick, I don't find blonde copilots to be any better at flying than brunettes or redheads. I do find that female copilots generally smell & look better than males, though. :p

Personally, I'll take range & speed over Cat A every day. If the fuel gets used up before you finish the ILS, Cat A means nothing, & if you can't load on enough fuel to get to the destination, Cat A means nothing. I'll take range, speed, EGPWS, TCAS, etc and take my chances with OEI ops.

[Nick Lappos]

widgeon,

Phil fits the basic description, but somehow I was hoping for more.....

[Xnr]

NightPilot

Would you take your chances landing in a built up area on a pad that is restricted to Cat A performance helicopters knowing full well that your bird is not certified to land there.

Its all about legal liability.

[Nick Lappos]

I just re-readthe thread, and Steve76 says it all.

What we want is improved safety, not necessarily redundant engines. Let's all try to remember that safety does not come from mere redundancy.

I would wage that were it possible to magically make all helicopters full Cat A twins, the accident rates would rise, since most accidents have nothing to do with engines quitting on their own, accidents usually depend on pilots running out of fuel, or into the ground, or some such thing. If we improve the Cat A performance, we make the helo have less range, and you will probably increase the acident rate, when the aircraft hits the ground/wire/trees with two big engines.

I advocate no hard rule on improving aircraft, except to work constantly to fix what goes wrong with the whole system, of which the airframe is actually a small part. Examples:
Fix the airway infrastructure and operating rules, so we have good helo IFR procedures and routes (No more CFIT). Fix the helo flying so we can control the thing at night and in cloud (No more brownout or mis-orientation accidents).

Can we think of other things to fix so that we actually raise safety?

[SASless]

Nick,

I would re-write FAR Part 91 so that it incorporates the exact same visual light reference for night flight that FAR Part 135 does for VFR Flight. (and then enforce that rule....)

As the rule is written now....and as is often ignored by commercial operators....allows for VFR/VMC flight without any requirement for surface light reference by which to control the aircraft visually thus generating "instrument" flight conditions for crews that may not be equipped or trained for IMC flight.

[Steve76]

"Fix the helo flying"
Good comment from Nick.
Sure you can have full Cat A requirements but it is all very redundant if the operator at the time is well out of the parameters for the Cat A approach. I'm seeing that it is difficult enough at the moment for a new guy who flys 1 helipad approach every 3 days to get it right with sky blue, 20kts on the nose and only 600lbs in the aircraft. :rolleyes:

Perhaps a little lateral thinking is required and those certified helipad should be decertified. Its amazing that so much beauracracy can be generated for the .00008hrs of flight time spent in the "danger" zone on approach or finals.

Anyway XNR me ol' china, I have adequately proven that you can land on of these things on the numbers without Cat A and only one engine.... Just set up for a zero speed auto each time and "bobs your aunty mate!"

And another thing. I know b@ggar all about JAR ops but the little I do appreciate leads me to the conclusion that I hope to never have to operate under those rules.
No offence to the lads in the old country; but JAR sounds a little anal retentive. North America and Australasian aviation is surviving well without all the hassle that would be incurred by adopting this system.

Nick: My input for safety.....EFIS with the radar, GPS etc all integrated and fed into that lovely little 6 inch screen. Without a doubt the best tool for situational IFR awareness and reduction of workload in the cockpit. Making GPS screens about twice the size would be a good idea as well. :D

[Xnr]

Steve

I think you are missing the point. Transport Canada has restricted certain helipads in Canada to Cat A performance. The aircraft you fly is not certified to land there. If you land there you are illegal.

Flying your approach like you are doing a zero speed auto scares me and will end up increasing the controlled flight into terrain statistics. Even though an excellent pilot like yourself could put the aircraft on the spot from 500' with both donkeys gone I am sure that the average bloke can't. When you train with your fellow pilots how many guys can put the aircraft on the numbers zero speed OEI. We are trying to make this aircraft do something that it wasn't designed to do.

The point of this thread was to find out which "new generation" birds have this capability. Not that many by the sound of it.

Lets talk specifics. The S76A cannot land at these helipads legally, nor can a 222A, the S76C is only certified to land at these restricted helipads "day only".

Pilots and operators don't understand the effect of the restriction.

Shawn

I don't feel that the regulators understand the effect of the restriction also. How could they? The pilots that are supposed to be current on type don't understand.

As we all agree we would rather have such things as range, reliability, and payload in our Xmas stockings long before we ask for Cat A helipad performance.

Maybe the restriction should be by "type" depending on the reliability of the engines installed.

[Shawn Coyle]

xnr:
It may come as a bit of a surprise, but there are a lot of helicopters out there flying that are Category A certified. The S-76A is one of them, because, unless I'm really wrong, the UK CAA certified it, albeit with a performance penalty.
I'm also pretty sure that the helipads in Canada had a 'let' for something like 'demonstrated engine out performance' - at least that's what I tried to get put in, as we had an interesting situation with the S-76A doing vertical takeoff profiles that were not permitted by the basic flight manua.
NickLappos, I might add, was extremely helpful in getting this situation remedied to the satisfaction of nearly all concerned. Long story.
Category A is not normally required in operations in North America, which is a bit of pity- the requirement does a lot to teach helicopter pilots about performance. This increase in knowledge drives up the safety levels, just by virtue of being there.
One of my friends at a large helicopter manufacturer said there was a different level of operation and safety between the operators of single engine helicopters and twin engine operators, and he couldn't pin it down to anything other than having to consider a lot more when operating the machines.

[donut king]

XNR,

Does your operation mandate Cat A performance as per SOP's/ customer requirements/ air reg's/ etc....??

In fact, anyone out there, does your job mandate Cat A op's at all flight regimes????

D.K

[Steve76]

As an operator under Canadian 703 regs, we need to be able to maintain MOCA under IFR conditions. (True XNR?)
Therefore Cat A in those situations.
Makes good sense to plan to be able to maintain MOCA regardless of Cat A restriction or not while IFR I think :rolleyes:
(ps: I was only joking about the zero speed thingy.... you living legend :D )

[Xnr]

Boys

Transport Canada has restricted some helipads (usually rooftops) to Cat A performance helos.....I am very doubtful if any of the aircraft you are flying are capable of landing at these helipads Cat A. Our aircraft have not been certified for zero speed helipad landings.

As Nick says very few have been certified for this (except the S92) and if your aircraft is.....it will be at a highly reduced gross weight.

The problem is two fold. First many pilots believe that if in the front of the AFM it says Category A they can land at these restricted helipads. Second Transport Canada has no idea what a certified Category A bird is capable of. Most helipad inspectors believe (and some pilots too) that Category A certification in the AFM is for zero speed helipad landings. It is not. It is for a rolling landing at a heliport where there is room for a run on of some sort.

Transport Canadas mandate is public safety. With this I can't argue.....but to place a performance restrictions on a helipad that very few present day helicopters are capable makes me wonder.

Do they want all operators to buy new aircraft or did they really know what they were doing when they imposed this restriction.

[Shawn Coyle]

Steve76:
Category A has nothing to do with being able to maintain MOCA in IFR, at least not that I'm aware of.
xnr:
You can pretty sure that the folks in Ottawa who made the decisions are aware of what Category A is. To refresh your memory there are normally four different situations for Category A - long runway, short runway, ground level helipad, and elevated helipad. For example, at least one helicopter has a limitation in the elevated helipad performance relating to the helipad size. You can't use Category A performance and limitations if the helipad is smaller than that size because of touchdown dispersion.
Read the Advisory Circular for Part 29 helicopters, found in the FAA web site - it's pretty illuminating on how the testing is done, and what the performance figures look like. I know the Bell 430 Category A Flight Manual Supplement (FMS) is nearly as thick as the 'normal' manual, and it is not easy to work out - not because Bell or Transport Canada are trying to be difficult, but because this is now as complex as calculating takeoff distance and V1 speeds in big fixed wing airplanes.
Remember this is all about trying to ensure a level of safety for helicopters with the capability to carry a lot of people. Life ain't simple anymore!

[helmet fire]

XNR,

I believe you may have misunderstood CAT A as a certification. Most twins that have been certified to CAT A have a supplement that specifically details those procedures. Typically (but not always) there is four chatrts to decipher when planning CAT A depending upon the helipad dimensions:

1. Full runway
2. Short landing strip where the "roll on" landing can be achieved.
3. Elevated helipad (helipad above surrounding terrain or obstacles, ie oil platform or building top).
4. Helipad at ground level (no room for roll ons).

To give you an idea about performance, in a fictional twin of say 10,000 lbs MAUW it might claim to be "certified CAT A". When you go to the supplement, you find that it is CAT A at 10,000lbs for runways, but only CAT A when operated at less than 9000 lbs for short strips, less than 8000 lbs for elevated helipads, and less than 7000 lbs for ground level pads.

Thus in your Canadian Example where the pad is restricted to CAT A ops (lets say it is an elevated helipad) we can operate there legally as long as our take off / landing weight is less than 8000 lbs.

Despite your inferences, most twins I have flown have CAT A supplements - including even the AS355 F1 !! - and therefore they can be operated "CAT A" if required. "Full CAT A Certification" is usually meant to infer that the aircraft is capable of CAT A to a ground level helipad at MAUW under reasonable OAT/DA situations, but these are very few and far between and the label is ill defined. So whilst the AS 355 F1 is not a "full CAT A machine" per se, it can legally use your CAT A helipads when operated in accordance with the CAT A supplement.

Hope that helps.

[donut king]

As a Canadian colleague of mine pointed out, TC requires some helipads .... Cat A helicopters only or equivalent certified Op's specification... or some wording like that. Correct us if we're wrong.

Secondly, flying offshore, we limit a/c weights off the rigs to maintain some kind of " Cat A/ Cat 1" performance.

D.K

P.S. Good discussion!!

[Xnr]

Thanks Shawn

I picked up some very useful info from the FAA site.

I will be looking for the Transport Canada equivalent.

This brings me back to my initial question.....maybe we can talk specifics. I will accept ballpark figures.

Can we list some twins which are certified for Cat A ground level helipad (vertical) operations and their corresponding gross weights on a standard day?

[Xnr]

I'll start.

S76A not certifed to Cat A for vertical operations from ground level helipads.

222A ditto.

This is to the best of my knowledge....please correct me if I am wrong.

[offshoreigor]

Hey guys, Happy New Years and sorry I'm late (as usual).

Cat A???????Cat B????? Hey, I thought we went Class I, Class II? Anyways, how about the 212 and 61? Both have a published CAT A Profile.

I love the concept, but when do we use it? Hmmm? How about any time we go off a helideck? Enhanced Class II sound familiar to anyone?

Well thats all for now.

Cheers, :rolleyes: :eek: OffshoreIgor:eek: :rolleyes:

[keepin it in trim]

The EC135 with turbomeca 2B1A1 engines, and the right software mod, is Class 1/old Cat A for helipad at Max AUW (2835KG). It is also single pilot IFR... and very nice to fly thank you!

[GLSNightPilot]

Xnr, I don't fly in Canada, don't intend to ever get close to Canada, therefore I'm not worried about legalities of Cat A landings. I don't intend to ever again venture north of the Red River (the one our President patrolled during the Vietnam conflict as a member of the Texas Air National Guard, watching for invaders from the north). It just gets too cold for me. :eek:

That said, I know that the S76A++ & 412 can be landed single engine to a platform. I've practiced it both in the sim & in the aircraft. You're likely to get a little movement at high gross weights, but a few feet is normally acceptable, if you planned the approach correctly. The S76C+ has a 'training mode' that allows restricting the power to single-engine levels for practice.

[helmet fire]

XNR,

AS355 F1 (MTOW 2400 kg) Cat A level helipad is 2090kg at SL/30 degC. The N model will do it at 2400 kg.

I see what you are getting at now though (appologies for the above sucking eggs stuff). The supplement in our F1 states "Though the helicopter is not certified to FAR 29 for Category A operation this supplement deals with the procedures and performance allowing the aircraft to be operated in a similar way." In other words, the aircraft can be operated to Cat A but it is not actually "certified" as such. I think that was your point XNR wasn't it?

[Xnr]

From what I can read the criteria for landing on a platform allows you to carry more payload than a ground level helipad.

My point in this discussion is that the Cat A ground level helipad performance restictions turns most twins into aircraft that are operating at not much more than their empty weight. They have very limited payload. I agree that the new generation aircraft are better.

Do you have any such restrictions to helipads in the U.S. and if so how is this restriction worded.

IMHO a restriction of this sort basically disqualifies aircraft with proven reliability from landing at that helipad (i.e. S76A )

I agree with most who say it is better to have reliability that full Cat A performance.

Helmet

So if your aircraft is not certified and the helipad is restricted I guess you can't land there either.

[Steve76]

XNR; Which pads Mate?

Shawn: with regards to the 703. Its my understanding that to hold a 703 approval you must be able to maintain at least MOCA IFR. Thus to maintain MOCA in our op. we should be looking at 30min power at 150ft/min ROC. Thus the same req. as Cat A or Class 1. I have been wrong before thou....

Howdy OffshoreIgor? How are those aussies treating ya?
Kick them where it hurts for me please :D

[Xnr]

Check the roof top pad in your area and any other pad that is in the middle of a built up area without a suitable reject site other than the pad itself. (Check the CFS)

Chances are that they have had this restriction placed on them.

A couple of roof tops out east have a restiction that reads something like "the aicraft must be able to maintain 4.5 metres (15') above all obstacles on the approach and departure path OEI."

Thats a pretty tall order.

The problem is that guys don't realize that the pads have been restricted and are continuing to land and take off at near gross weight.

If there is ever an incident the laywers will have a feeding frenzy. Every finger will be pointing at the pilot.

With regards to our op we must be able to maintain the MOCA OEI (no rate of climb) but this is not a Cat A requirement.

[DeltaFree]

All twins I have flown have have Cat A capability, clearly with restricted weights, some better than others. The AS355F1 is perfectly capable of helipad departures and arrivals, and to be honest the figures given seem quite relaxed ie. it is not too big a deal if an engine does go bang. With newer machines the limits seem to get pushed harder such that if the worst should occur then there is little margin for error. The 355 has very basic graphs giving a fixed profile, the 365 has variable Vtoss and Vy to give more options depending field length. The added complexity increases what we can do legally.
All manufacturers want to get the most out of their machines, which means if they can they will work closer to the limits, so long as we are professional in our approach this is fine, but it does leave a door open to getting caught out if we are not.
Remember Cat A is for the whole flight so guaranteed ground clearance in the cruise is part of it, and during climb out, 3% is 150ft per mile, a 500ft hill 3 miles away gives more than 3% gradient.

[GLSNightPilot]

In the US, there is no requirement that I know of to comply with Cat A anywhere, anytime. I know of no pads which require it. Common sense may dictate otherwise, but there is no regulatory requirement. Some local government entities may have their own requirements, but I don't know of any.

[Xnr]

Thanx GLS

How about you guys across the pond.....any such helipad retrictions on rooftops or ground level helipads in built up areas??

[Shawn Coyle]

Steve76:
I was in the fortunate position to never have to interpret the operational rules (703, etc.). But you can do the MOCA thing in many helicopters that do not have Category A performance. Two completely separate things.

xnr
The wording about demonstrated performance (instead of just Category A) is something I'll take credit for. I suggested that, particulary for the S-76A, there was a supplement for less than 9 passengers (i.e. air ambulance) that had a demonstrated vertical takeoff profile, and that it should be given credit for that. Very long story about that whole thing came about.
Transport Canada uses the same regulatory material as the FAA for certification (i.e. Part 27 and Part 29).
The UK CAA recognized long ago that Part 27 helicopters, specifically the AS-355 series, could demonstrate Category A performance, but may not have had some of the other features needed to get Category A (engine isolations, and other very esoteric, but important things).
This has been a great discussion.

[SASless]

Far 91.3 allows an offshore operator to momentarily breach the H-V limitations for Part 29 certified helicopters, from an elevated deck if the water is suitable for an intentional landing and the helicopter is equipped with floats. The reg does not address or specifically talk about land based elevated decks......wonder how all that figures in??? What if you have an elevated deck without adequate forced landing areas below....can you still violate the H-V limits as so stated in the 91.3 reg? This would apply to very many of the EMS Hospital pads that some 412's operate out of....and with the Bell method of putting H-V diagrams in the Limitations section of the RFM.......

Care to address this situation Shawn or Nick ?

[Thomas coupling]

This subject is going to get a lot more heated when/if the annex 14 regs NPA18, come into force. JAR Ops 3 is looking to allow only true Class 1 (old Cat A) into out of hospital landing sites as of 2004/5/8 depending on who you talk to. Either the operator will have to buy a true Class 1 helo or the hospital will have to re-build its landing site to accept Class II ops.
Class I will become more and more the norm for more commercial ops as the european regs bite.

[Steve76]

Went to the roof yesterday champ....
I was thinking of you.... isn't that nice! :D
I think that TC were only considering the departure performance and never considered the arrival aspect when they placed that paragraph in the CFS.

[Xnr]

Shawn

My understanding is that the S76A supplement for Cat B operations for 9 pass or less is just a reprint of the H/V chart in the supplement section.

It does not include a vertical profile procedure.

Some companies have developed vertical procedures and are now allowed to use them Cat B because of this supplement.

It is my understanding that they can now enter the H/V chart because it is no longer a restriction but now an advisory because of the reprint in the supplement section.

It is the first time that I have seen anything in a supplement that is only advisory.

Steve76

I am flattered to hear that you were thinking of me MATE.

[Shawn Coyle]

xnr:
You are not alone in being confused about this. This is what caused the problem in the first place. More than 9 passenger helicopters (all of which would be Part 29 certified) have the HV chart in the limitations section. You are not, repeat not, allowed to operate there.
BK 117, which normally has less than 9 passengers (and the HV chart in the performance section), has a supplement for 10 passenger configuration - the HV chart is moved to the Limitations section in that supplement.
The S-76 is normally configured for more than 10 passengers, so the HV chart is in the Limitations section. The less than 9 passenger supplement allows it to be moved to the performance section.
Because the HV chart is now no longer a limitation, the vertical profile can be used.
If there is a Category A supplement for a helicopter, it will have wording in the supplement to the effect that the HV chart is not a limitation when using the Category A performance charts and profiles.
Supplements have the same authority as the rest of the flight manual, they just supplement it. Normally this is for additional equipment, but for Category A (and less than 9 passengers), this is a normal state of affairs.
All Part 27 helicopters have the HV chart in the performance section - it is not a limitation for those machines.
Look carefully at the wording at the beginning of the limitations section - it will say something to the effect that you must observe these limitations - what many people do not realize is that by exceeding those limitations, or operating outside of them, they have gone outside the area that is certified and in the Type Certificate Data Sheet, and have invalidated their certificate of airworthiness (and therefore their insurance...).
The things I learned at TC about the flight manual that I'm sure most pilots aren't aware of was pretty frightening. You may have seen something in the Aviation Safety Newsletter some time ago about 'what commercial pilots need to know about certification' - I wrote that to try to prevent problems like this. It was considerably cut down from what I wanted to say.
I can send it to you if you contact me off-line.

[Xnr]

Shawn

Yes, that is pretty much how I understand it also. But this brings up a very interesting point.

Lets say that you are operating a S76A in the off shore configuaration....you are on the rig and you have more than 9 passengers on board.....your helideck is 100' above the water.....as you aircraft leaves the deck you are now within the H/V chart.

So from what you said in the above post you are not in compliance with your C of A and your insurance is now void.

[Shawn Coyle]

Interesting point. But I'm sure there is an answer somewhere. The legal point is that your takeoff performance was (probably) based on the helipad. I'll check with the ops people to see what they say.

[sandy helmet]

To XNR

As I understand it, only Performance Class 1 helicopters are permitted to operate from elevated heliports or helidecks across the pond.
These are helicopters which, for take-off purposes
" shall be able, in the event of a critical power unit failing at or before the take-off decision point, to discontinue the take-off, and stop within the rejected take-off area available, ....or if past the take-off decision point, to continue the take-off, and then climb, clearing all obstacles along the flight path by an adequate margin......" (ICAO Annex 6 Part III)

Narrows it down somewhat, eh?

[Xnr]

I believe that the rules have been tightened yet another notch, thus the topic of this thread.

In Canada, my understanding is that Class1 (Cat A) performance helicopters may operate in 2 different categories and the regs for each are not the same.

As Shawn says you can operate with less than 9 passengers or more than 9 passengers.

If you operate with less than 9 you may enter the H/V chart for the purpose of your operation.....if you are operating with 9 or more you may not enter the H/V chart for any reason.

Therefore my question was if you are coming off a rig with 9+ passengers on board, as soon as you leave the deck with low airspeed you are now in the curve.

[Shawn Coyle]

The 9 passenger thing is even more subtle than that. It's not how many passengers you have on board, it's how many you can carry in that configuration.
So, if you're in the 12 passenger configuration, but only have 9 passengers on board, you are still governed by the 12 passenger (i.e. no flight in the HV curve) limitation. If your configuration is for 9 passengers (and for the S-76, this requires a Flight Manual Supplement), then and only then can you use the HV in the performance section.
Conversely if you have a BK117 in the 'normal' (less than 9 passengers) then you can fly into the HV curve because it's in the performance section. Put the high density seating into the machine and the HV curve moves to the limitations section regardless of the number of passengers who actually get into the machine.
Subtle, eh?

[Xnr]

Thanx again Shawn

Did you come up with anything on how an aircraft when configured for more than 9 passenger can lift off a rig or elevated helipad legally.

I have been asking around and the only answer I could get is "they can't ...so everyone just does it illegally"

What do you say?

Cheers

[Shawn Coyle]

Let me check with my contacts....

[4dogs]

Folks,

It has been an excellent thread, perhaps more incidentally than directly.

Despite the generally high level of technical input, the untouched issue seems to be that which gave rise to Xnr's original question: is the regulator, in this case TC, justified in placing operational limits on certain helipad operations?

I will presume that TC is constrained to act within the public policy imperatives of the Canadian Parliament and thus is reflecting the desire of its political master to reduce the risk to the general public, perceived or otherwise, of helicopter operations into these places. Operating rules are designed to protect both the travelling public in aircraft and those on the ground who may be exposed to the post-accident "metal rain". Category A or Class 1 performance rules are simply risk minimisers and that is why the concept exists. It seems quite logical that the certification rules reflect public policy and that the cost/benefit argument has been run and won.

All of the "what I would prefer" stuff is largely irrelevant.

I, too, loved it when I had one big engine and ******-all rules and could carry more further and faster than anyone else, but I also knew that there were a lot of things that could turn all of that fun into disaster and kill lots of people and destroy lots of property. But if I want to run a business in certain transport modes and within certain communities, then I know that the risk of all that fun is not acceptable from either a commercial or a social perspective. And that, folks, is why Nick works so hard to help produce an affordable "true Cat A" machine - the market demands it because certain societies demand it.

As Shawn has clearly identified, the true task of the industry and the regulator is maximise the utility and minimise the cost of the public safety rules. I see in this debate the same misconception that plagues the Australian aviation scene and actively hinders industry progress, so say after me: "The regulator does not exist to satisfy the whims of the industry, it exists to satisfy the whims of the general public!"

It has to be recognised that certain societies are prepared to accept higher transportation costs to pay for higher levels of safety, perceived or otherwise, or, if that transport mode cannot be provided economically, are prepared to find alternative modes.

The danger to all helicopter operations in urban or high value areas is that it will only take one accident to one "redneck" actively flouting the rules, regardless of the reason, to create a public backlash that we will never get over. The solution will not come from civil disobedience - it will come from close and positive engagement with the policy makers, combined with sound risk analysis and identification of the social benefits of helicopter operations that appeal to the masses who overwise see us as noisy, dirty and far outside their financial reach.

As for the HV Diagram and seating configuration (??) argument, that looks like the first target for some serious lobbying and regulatory review....

Stay alive,

[email protected]