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View Full Version : Single Engine Ops: Who's Responsibility?


Yellow & Blue Baron
27th Jun 2010, 18:16
Oil and gas companies, some large corporations and most government departments either have policy or guidelines addressing flight in single engine aircraft. Presumably the insurers of celebrities also issue terms covering the use of charter flights by their policy holders?

What obligation do you think charter companies have to ensure their passengers understand that they are chartering a single engine aircraft?

http://bauergriffinonline.com/bfm_gallery/2008/08/katie%20holmes%20081108/post_image/post_image-80810D8_HOLMES_K_B-GR_01.JPG

Mrs Cruise (Katie Holmes) boards an Astar at Wall Street Heliport with daughter Suri Cruise in arms.

Hell Man
27th Jun 2010, 18:30
In America's litigous society charter operators might do well to check that their client's understand this, especially given that they have the resources to take action in the event of an incident but then the firm would have to make sure that such information was equally shared with non-celebrity pax.

Small firms running only single engine ships just want the money and publicity so they probably don't mind.

Two questions if anyone can respond!

1. Can anyone provide me with a first hand incident of a total engine loss in a twin as a result of mechanical failure (no external influences such as water/foreign object ingestion)ie: a 100% pure mechanical failure.

2. Does anyone know where US helo pilots hang out online? There are a few on pprune but not as many as I'd like. Any info welcome.

Hasta la vista!

Gordy
27th Jun 2010, 18:50
Yellow and Blue...

Oil and gas companies, some large corporations and most government departments either have policy or guidelines addressing flight in single engine aircraft.

Why do you care? Or are you just stirring the proverbial sh1t. You are by your own admission a military pilot in Sweden.

And you are wrong---the GOM is full of single engine helicopters. Most government contracted helicopters are also single engine, certainly for DOI, USFS, BLM etc....

You will find that the vast majority of celebrities know what they are flying in---a fair bunch of them own their own aircraft.

Hell man:

Small firms running only single engine ships just want the money and publicity so they probably don't mind.

Not so---I work for one of the "small firms" that does a fair amount of celebrity charters, and we are extremely discrete...due to their privacy concerns, we never disclose who, when, or where we fly. So no publicity there....

Most US helicopter pilots hang out on JH.

Shell Management
27th Jun 2010, 18:56
Typical pig-headed US attitude there Gordy that nicely explains the poor US safety record.

Too often people who can afford to fly safely don't due to their igonrance of the risks (including the hostile environment risks).

I'm glad to see that BP are sticking to their principles and limiting SE helicopters to shore patrols in the GOM.

JimBall
27th Jun 2010, 18:56
Sorry, I read the UK CAA reports & MORs - have I missed a load of failures in the donkey dept of SEHs ?

I see a lot of chip lights, hydraulics and other bits failing in twins - which leads to a forced landing and the inevitable report - but I see far great reliability and less stress in SEH.

Insurance companies would prefer that we all stay on the ground in a cottonball and never go anywhere - hence some of the ridiculous "keyman" requirements which sometimes include mandatory multi-engines for any flying.

As ever, it's a way to ramp the premium by creating a risk far greater than it really is.

Hell Man
27th Jun 2010, 19:05
Was actually wanting to know about first hand 100% mechanical engine failures because I've never actually met anyone who's had one!

The stats show than singles are pretty much as safe (if not safer) but I guess its the 'what if factor'.

Here is something I've always wanted to know ... In a fixed wing you have (to a larger extent) seperate systems as a result of individually mounted engines but in helos (aside from the engines) the majority of other systems are shared.

Does this represent a lower safety threashold for twin helos vs. twin fixed wings?

Gordy
27th Jun 2010, 19:06
Shell Management

Typical pig-headed US attitude there Gordy that nicely explains the poor US safety record.

I did not state an opinion as to which is better...I merely stated that the GOM is full of single engine aircraft. Therefore, no comment to you.

Yellow & Blue Baron
27th Jun 2010, 19:16
I wish to publicly apologize to Gordy (and anyone else) if I am causing the cr*p to curdle! It is not my intention.

I am genuinely interested because one day I expect I will leave the Swedish Defence Forces and maybe I will have to join a small company which is operating single engine aircraft and these issue will become relevant to me.

I feel that singles are perfectly safe because of the helicopter's ability to auto-rotate. If the aircraft is flown along safe single engine routes (open spaces below) and at the right height with the right visibility then it is perfectly safe.

hostile
27th Jun 2010, 19:59
It would be nice to go and look long term records of accidents and compare them between singles and twins. What I would like say is that helicopters have a lot of single parts, which will broke also. Major parts are at least: tail rotor, Gearbox(es), rotor system itself etc.
First thing is go and look where to work and how the company manage all services. Also pilots have a responsibility to operate aircraft's by the manuals as well. All limit exceeds are bad news and if you do not have any kind of flight monitoring systems (like most older single engine helicopters don't have) will reduce your safety. That's why you need to be honest, if it happened accidentally. I don't believe anybody exceed limits for in purpose anyways. Single engines are very reliable nowadays, if you look flight time records. That's imaze me, but it is true. All big sight-seeing companies basically use singles and they flies a lot. Offshore is the other operation for singles. Reason for using singles in some part of areas are small platforms where you cannot build a big helideck for twins. Well' you can use EC135's or other same size aircrafts, but operational costs are total different then. Money might be the only reason to use singles, but they can be safe.

Hostile

Hell Man
27th Jun 2010, 21:18
I do feel that there are some very important factors relating to twin engine helo ops, especially the shared dynamic systems. I realize its very similar for fixed wings but multi engine fw do have the advantage of largely separate propulsion/thrust units and which I believe offers an added level of safety.

One solution, from a cost perspective, would be an engine technology which allows for very high short term power demands of say up to 10-20 mins (for emergency single engine operations) from smaller engines which would offer more economic operating costs for twins.

But, the way things are going in the H&S world we live in I am sure singles will end up as trainers and private use only.

Here's a single op that recently had the hangar door closed on them: Rescue copter loses out | Stuff.co.nz (http://www.stuff.co.nz/taranaki-daily-news/news/3860226/Rescue-copter-loses-out)

500e
27th Jun 2010, 22:10
The letter claims that since January 1999 there have been 17 incidents in which helicopters either needed to shut down engines due to warnings, or made precautionary landings because of mechanical failures or warnings. All these incidents were during air ambulance operations.
Do others think this is a high No, of problems ? for Air ambulance work

ricksheli
28th Jun 2010, 06:44
500e Heli Man

Some of those 17 reports will have been filled by myself, both in singles and twins. This is a sad case of the Civil Aviation Authority using "incident" reporting to try and justify their stance - many of those reports (I'm assuming) will have been for "chip lights", 'fluctuating oil pressure" etc, pilots responded to the "warnings" and carried out a precautionary landing, or shut a second engine down. Many of these reports, most probably, where cleared quickly by an engineer, then an incident report was generated. This is good practice, but now our CAA are trying to suggest that these 17 reports indicate that engines are not reliable, and this is how the media will take it! Yes I accept, engine failures do happen, but the overall risk needs to be assessed against the added cost of operating 2 engines.

jellycopter
28th Jun 2010, 07:37
Hell Man

I had the Compressor Drive shaft shear in an Agusta A109C, total power loss from that engine with TOT off the clock.

That said, I also had the turbine let go in an AB205, total and instant power loss.

No pre-determined cause in either instance, just the 'sh1t happens' category.

So that's one all in the single / twin argument in my personal experience.

JJ

bolkow
28th Jun 2010, 08:21
Last year I lost a friend in a single engine eurocopter, he was inspecting electricity lines somewhere on the west coast of Ireland when the chopper (EI-IHL) sufferred a mechanical failure, main gear wheel disintegrated. Pilot survived the resulting crash but he did'nt.

Coconutty
28th Jun 2010, 08:32
Speculating :

Perhaps the most likely cause of a double engine failure would not be a mechanical fault with the engines,
but loss of fuel - i.e running out of ( useable ) fuel, causing them go very quiet.

This could be attributed to pilot error, poor maintenance, or possibly even mechanical failure of some sort,
perhaps even a multiple bird strike in the right ( wrong ) place, but none of these are restricted to twin engine aircraft,
and are just as likely / unlikely in a single - probably even more so in some cases.

I can ony think of a couple of examples of twin failures -

The Dyfed-Powys 109 G-DPPH that ran out of useable fuel in 2001 following maintenance to fuel pumps,
and I seem to recall there was an incident back in the '80's / 90's ( I think ) where a Police twin squirrel
( or maybe even a 902 ) lost fuel supply because of detached fuel line(s) -
resulting in an auto and run on landing into a field. Can't find any details on that one though.

http://i34.photobucket.com/albums/d129/coconut11/Coconutty.jpg

SuperF
28th Jun 2010, 08:36
Hi Rick.

Unfortunately, the rule is the rule, and the current director of CAA is going to the letter of the law, rather than the intent, and churing through all the laws to see what we are doing wrong. Apart from the BK running into trees a few years ago, i'm struggling to think of any serious incidents that have been on EMS ops in NZ... somehow there are 17 in 10 yrs. Last major one was a JR flying into a white out, and the army wrecking an Iroquois on Mt Cook, both in the 80's.:rolleyes:

like you said chip lights and pressure fluctuations, which wouldn't have been reported 20 yrs ago, just talked to the engineers, check it out, watch it, fix it...

Hell Man
28th Jun 2010, 09:11
Was not asking about engine failure in singles (even I had a flame out in an Iroquois in Nam) nor about 'double' engine failure in twins but ... a single engine failure in a twin.

Jellycopter has had it in a 109C. Congrats! You're the flirst helo jock I've 'met' to whom this has happened!

The thing is, and the reason for my asking, is that these incidents of mechanical engine failure must be very rare. I'm trying to establish how frequently a second engine keeps an aircraft from calamity vs. single engine. I guess Jelly landed pretty smartly after the failure but some twin ops (over water at night) etc. may require sustained flight.

What are the stats? Are twins statistically safer than singles?

thecontroller
28th Jun 2010, 11:09
http://www.pprune.org/rotorheads/291055-where-does-uk-jar-twin-only-mentality-come.html

JimBall
28th Jun 2010, 11:18
Are twins statistically safer than singles?

The unanswerable question. You seem to have strayed from "engine failures" to a wider view of incidents. Even "bolkow" above hasn't stuck to engine failure as a cause - but was the gear failure caused by too much torque from 2 engines ?

The only facts I know are that 2 engines cause more stress for related systems, and that the advances made in engine reliability over the past 40 years have still not made it through the system with a decent set of regulations for SEH. (In the UK & Europe). There is still a heavy bias against SEH when the stats and the reality don't demand it.

Can all twins at all weights operating at, say, 750ft AGL safely depart the area when a power unit fails ? No. Can the same machines safely auto to the ground from that height ? No.

Hell Man
28th Jun 2010, 11:52
I've read thru the thread posted by thecontroller and it is interesting.

I can understand the reg bodies pushing for better safety (that's good) but don't know whether twins = better safety period?

I seem to remember the UK going through a period of fatal TwinStar crashes flying VIP/Corporates - the extra engines didn't help then!

I think the answer in the long run may simply be to produce really reliable, well powered and highly fuel efficient turbines so that twin safety, performance and economy is beyond question.

Yellow & Blue Baron
28th Jun 2010, 12:12
Hell Man!

I think the answer in the long run may simply be to produce really reliable, well powered and highly fuel efficient turbines so that twin safety, performance and economy is beyond question.

And I think I have the answer ...

A Stark Industries Arc Reactor powered turbine!!! :E

http://t1.gstatic.com/images?q=tbn:NT2FpM913bKjXM:http://i108.photobucket.com/albums/n25/tehachapi_2006/ARC_Reactor_by_minimamente.jpg (http://i108.photobucket.com/albums/n25/tehachapi_2006/ARC_Reactor_by_minimamente.jpg)

rick1128
28th Jun 2010, 13:51
From what I have seen, read and heard, the major reason why IMO the US seems to have more accidents than the JAA countries is that a larger percentage of what we do with helicopters is deeper within the 'Money' Curve, aka HV Curve. I haven't seen any heli-logging or rappelling in Europe, except the rappelling done by police or special ops people.

As for the age old question of a twin being safer than a single. The accident records here in the US, show almost no difference between twin and single. If an actual engine failure does occur in a turbine engine it is usually fuel related. If it is a mechanical failure (quite rare, considering the number of hours flown) with the engines side by side in most installations, parts quite often end up in the 'good' engine. As for the containment ring, all that seems to do is ensure that the parts go into the good engine, not through it. I can say that I speak with some experience. In my flying career I have had 9 engine failure events. Surprisingly, only four were in piston engines. One was caused by a system failure that filled the oil tank with avgas and burned out the engine. It was traced to an AD note that wasn't complied with. Another was caused by a shop that didn't overhaul a fuel control unit that they claimed they did and the engine flooded out. The other two were caused by cylinder failures. Which is always a weak point in turbocharged engines. Two of the turbine engines had T wheels come apart due to improper overhaul (by the outside vendor). One was caused by an oil pump failure and another was a FCU failure. And the last, was a FOD failure. These were ALL multi engine aircraft. IMO the more engines you add the more your risk of an engine failure increases exponentially. Further more, except for the piston fuel control unit failure, which happened in cruise flight, all happened on takeoff. From what information I have gotten, a majority of actual engine failures happen right after a major power change and most often when the power has been increased.

The engines feed from the same fuel tank, so any fuel issues, lack of or contamination will affect both engines. And the engines are connected to the same transmissions, with a few exceptions. Many of the mechanical failures over here are not engine issues, but component issues like transmissions.

On top of that many twins have a minimum single engine speed, which would make landing on a hospital heliport difficult if not impossible. Personally, I feel just as safe in a single engine helicopter as I do in a twin. As for a single engine airplane, that really depends.

perfrej
28th Jun 2010, 18:45
I think I recall something about combining gear box failures being a main issue in the North Sea operations. Is this true? If so, then that would be a definate factor against twin engined "reliability".

thecontroller
28th Jun 2010, 18:52
Two pilots will ALWAYS be safer than two engines. 'Pilot error' accounts for th vast majority of crashes.

Agaricus bisporus
28th Jun 2010, 23:02
Exactamundo, controller.

Clearly it is a "given" that twins are safer than singles, "everyone knows that", its "obvious".

Isn't it?

If the complxity of an aircraft increases as the exponential of the number of engines and the vast majority of accidents are primarily or largely down to errors in flying/handling the problem is it any wonder that twins are little different to singles in the stats? I'm pretty sure that the minor safety advantage of the second engine is negated not only by the added complexity and variety of potential faults, but also the likelihood of mishandling them.

Two pilots, well, if they're trained as a crew maybe better, but two single-pilot pilots flying together because a charter client demanded it? Hmm...Sometimes a little knowledge is not so clever after all.

As to the "responsibility" of telling a client what he's flying in - why? Caveat Emptor. If he's concerned he'll ask. We'll be finding reasons to provide them type-related accident statistics next!

Earl of Rochester
29th Jun 2010, 10:57
Well put Agaricus.

Te_Kahu
30th Jun 2010, 12:17
ricksheli

You make a valid point! However, the CAA has been backed into a corner by the rescue trusts which have been deliberately misinterpreting the rule for years, and then using their massive public sympathy card every time they are challenged. Combine that with a Minister of Transport who has been warning them behind the scenes for quite some time that they need to up their game. This week he said it very publically.

Super F

The Director is interpreting the rule as it was intended. The exemption that is allowed to the performance criteria is for life or death situations. Broken legs or even backs usually aren't. Most medical cases, whilst often serious, aren't life or death situations.

A key issue is that of inter-hospital transfers! To use the exemption to justify using a single egined helicopter for an inter-hospital transfer is simply not credible. In the time that it takes to prep a patient, even a critically ill/injured patient, for a flight and arrange everything at the receiving hospitals end a suitable machine could be sourced.

The event which has alarmed many people in the corridors of power happened last September - well after this issue became public.

It was a Longranger suffering a main bearing failure shortly after landing at Taranaki Base Hospital. It had just bought a patient back from Wellington Hospital.

Both of those hospital pads are deemed to require Category A, Performance Class 1 aircraft to operate to and fro because of how built out they are.

TK

ricksheli
1st Jul 2010, 01:27
TK

Your information about the LongRanger into Taranaki Base Hospital is totally wrong. Sounds like the CAA/ ministers changing information to suit their argument. The facts: Helicopter was on a positioning flight from port, engine oil pressure began "fluctuating", helicopter landed at Base Hospital with full power, shut down normally. Fault traced to engine oil scavenge pump failure, but the point is, didn't result in engine failure, the fault allowed plenty of time for a safe powered landing, the pilot did exactly what the flight manual required.
As for medical transfer from Wellington - no. I can tell you the next flight after repair and air test was a flight to Wellington Hospital and the flight nurse signed to allow use of 13a.

snotcicles
1st Jul 2010, 04:54
Very well put Agaricus bisporus. It seems that far too many clients (and pilots sometimes...) believe that engines are the only failures that can possibly occur in helicopters. :ugh:

SuperF
1st Jul 2010, 09:28
Te Kahu
i agree about the trusts going at it and using sympathy to not have to comply. re the intent, i was referring to LIB4 which is the biggest foul up anyone has ever seen.

interesting seeing a LR land in Carisbrook at the end of the test match, took off striaght out over the crowd, didn't even try to gain any altitude. Waiting for CAA to jump on that one... Can't see it as being a sec13 excuise, and they are rescue heli operators and should know better...

you should google Taranaki Base, you should be able to do a steep turning descent and take off in most singles, and keep the grass below you, not like some of the other hospitals.

Interesting that Tom Cruise lets his wife and kid in a single and he flys around in twins???

Te_Kahu
1st Jul 2010, 10:23
Ricksheli.

Far cop. One is always willing to put one's hand up and call wrong if the facts dictate so. You appear to have intimate detail about this incident which I'm hoping means you might be able to answer a question or two!

How long did the Longranger sit on the hospital pad until the engine was swapped out?

Also, the fact that it had to shutdown and stay on the hospital pad for XXX days/weeks/months while the engine was swapped out means it complied with Cat A, Performance Class 1 how?

How long can a Longranger/C30 keep performing at full power with a failed oil scavenge pump before it's performance degrades and becomes a problem?

And, Port of Taranaki to Taranaki Base Hospital is how many metres?

I am sitting with a former senior manager of one of New Zealand's biggest hospitals and he just bout fell of his chair laughing at your suggestion that the flights out of New Plymouth are signed off by a flight nurse.

"That's a sad joke...Tell that guy not to say that to loudly in case the hospital's insurers hear," were his comments!

By the way, what was the nature of the injury/illness of that flight which was signed off by a flight nurse? Do tell?

SuperF

I think you will find that the owner of that Longranger simply doesn't agree with that rule and is just ignoring it! As well as the department I do wonder if his insurers were watching the test?

TK

Thomas coupling
1st Jul 2010, 12:08
Coconutty: The Dyfed Powys helo ran out of fuel because of pilot error, on Christmas Day 2001. He mis read the FRC's. No mechanical issues.

I have flown 3000hrs on Gazelles in my time. Probably approximates to 2500 -3000 flights in one. Not one power failure. In fact up until then there was not one recorded engine failure of a gazelle in the military until CB had one on finals to Predannack! I have flown approx 4000hrs in twins and I have experienced half a dozen 'forced landings' because of the complexities of flying twins.

Statistically the odds of a SEH experiencing total power loss are something like 14,000,000 : 1.
I have to say (apart from some helos requiring 2 engines to carry all the weight around), I suspect the 1 engine Vs 2 engine argument is all about perceived theoretical permutations and that 'pucker factor' flying over hostile terrain on 1 engine.
People can't grasp the odds. You would have to fly every day for 112 years before you died in a plane crash - yet thousands of people will never fly through fear of flying.
Interesting topic of conversation.

VeeAny
1st Jul 2010, 12:21
Had a compressor blade come off and destroy the rest of the compressor in a 109Aii.

ricksheli
2nd Jul 2010, 02:35
TK

Quite happy to answer some questions

you asked: "How long did the Longranger sit on the hospital pad until the engine was swapped out?"
It was only on the helipad until the ground handling wheels where attached and a/c pushed into hanger! The heliport is big enough for several helicopters, if thats your point? SuperF has a very valid point, I believe Taranaki Base Hospital is suitable for certain singles (B206, B206L, R44, AS350 etc) all helicopters have differing auto performance and I think in some singles you could plan an approach / departure for at Taranaki Base Hospital. Unfortunately the Taranaki Rescue Trust operate a A119 and that won't comply, the shame of it is that its new, and has a PT6 engine, probably the best turbine engine out there.

TK You asked:"Also, the fact that it had to shutdown and stay on the hospital pad for XXX days/weeks/months while the engine was swapped out means it complied with Cat A, Performance Class 1 how?"
Its a single so can not comply with Cat A, Performance Class 1, but if the hospital has suitable approach / departure routes and the helicopter has suitable auto performance this may not be a problem.

TK you asked: "How long can a Longranger/C30 keep performing at full power with a failed oil scavenge pump before it's performance degrades and becomes a problem? "
It would seem long enough to make a safe landing, but perhaps RR could answer that one?

TK you asked:"Port of Taranaki to Taranaki Base Hospital is how many metres?"
Just over 1nm, a park and school playing fields in between, the helicopter had been flying for the previous half hour, why the question?

TK stated:"I am sitting with a former senior manager of one of New Zealand's biggest hospitals and he just bout fell of his chair laughing at your suggestion that the flights out of New Plymouth are signed off by a flight nurse.
"That's a sad joke...Tell that guy not to say that to loudly in case the hospital's insurers hear," were his comments!"

If you are an EMS helicopter, the best people on board to assess the patient would be a doctor, paramedic or flight nurse, not flight crew. I wouldn't land at an elevated helipad in a single with a patient on board unless the medical crew expressed a critical requirement to do so. This was the case, and the flight nurse had no problem making a statement to the effect. Certainly no "joke" or "laughing matter".

Te_Kahu
3rd Jul 2010, 20:59
Ricksheli. Thanks for that. No one could argue that they are not perfectly reasonable answers. But, isn't the point that at the present point in time the department deems the Taranaki Base Hospital pad to be a Cat A, Performance Class 1 pad and really everything else is irrelevant?

What work have the local operators done with the department to convince them that there is a safe approach/departure path for singles?

In regard to a flight nurse signing off the 13A exemption! I would be interested to see what the insurance companies of the aircraft owner and the DHB would say. It is clearly outside the intent of the rule and the exemption.

For example! Last year the Palmerston North rescue squirrel brought a man into Wellington Hospital who had an angle grinder embedded in this forehead. That certainly met the intent of of the exemption. It is highly dubious that many of the accident cases and certainly most of the inter-hospital transfer cases come anywhere near meeting the intent of the exemption.

If the comment of Mr Wickham from the Phillips Trust typifies the attitude the rescue trusts, then the public should be concerned about how their money is being spent and the level of service they are being provided. It is my understanding that the Director's letter IS the response to their request for exemption.

The Square Trust rescue helicopter is "flying in the face" of air safety rules that ban single-engine craft from helipads in congested areas, and could be grounded within weeks.

The Civil Aviation Authority (CAA) has told operators and district health boards that from the end of August it will enforce rules governing the ability of helicopters to make emergency landings in populated areas in the case of engine failure.

The Square Trust rescue helicopter is based at Palmerston North Hospital.

In the case of any breaches brought to the CAA's attention after that date, 10 days' grace would be granted to comply with the regulations before the authority ordered operators to stop flying, said director Steve Douglas.

The Central Regions Emergency Services Trust (CREST), which uses Helipro's BK 117 twin-engine helicopters, has offered to come to the rescue of the service.

But the Philips Search and Rescue Trust, which manages the Square Trust's operations, said it is not breaking the rules.

Chief executive David Wickham said the safety rules were more complex than a single-versus-twin engine debate, and the trust was operating professionally and responsibly.

Helipro pilot Rick Lucas said the rules were clear. He said there was no doubt the approaches to the Palmerston North Hospital helipad meant flying over a congested area.

"An engine failure would have absolutely catastrophic consequences, yet they are still flying."

Mr Wickham said the prospect of having to invest in twin-engine helicopters was far from inevitable.

"The wheels aren't going to fall off the service in Palmerston North, with or without CREST."

Compliance with safety rules had to be professionally assessed, flight by flight, depending on variables such as the weight of the load, wind conditions, and whether there was medical advice that it was a life-and-death situation for the patient on board, Mr Wickham said.

"The degree to which you expose people on the ground to risk has to be considered against the danger to the person on board if you don't make the landing."

He said the Civil Aviation Authority had spelt out its time line for enforcing the rules, but it was still unclear whether changes would have to be made to comply with those rules.

Just in case, the trust had applied for an exemption, "what we thought was the best, most robust case", but hadn't had a formal response. In the meantime, it had lined up options for sourcing twin-engine helicopters.

Mr Wickham said twin-engine helicopters cost twice as much to run but were not twice as safe.

"But we can't crystallise any of that until we know more."

MidCentral Health group manager for support services Jeff Small said he couldn't comment at present on whether the single-engine helicopter service could continue to operate.

Talks with the Philips Trust, which holds a contract to provide air transport services until the middle of next year, were continuing.

ricksheli
3rd Jul 2010, 21:20
TK

With regard to your comment "...... But, isn't the point that at the present point in time the department deems the Taranaki Base Hospital pad to be a Cat A, Performance Class 1 pad and really everything else is irrelevant?"

Do you know that the department has deemed the pad to be Cat A, Performance Class 1? I only know that the operator has decided that the A119 cannot comply, so is now operating elsewhere. Every helicopter has differing performance, which will be affected by AUW, some twin engine helicopters at a high AUW will not comply either. The press, and non helicopter pilots (Trust managers etc), have really been struggling to understand the issue.

Te_Kahu
6th Jul 2010, 10:29
ricksheli. Good point squire. No I don't know that the department has deemed that as an absolute fact. I strayed into the dead man's curve equivalent - the assumption.

I assumed that as Mr Mark Marsters, the chair of the local trust, has been in the media several times recently saying they had asked CAA for an exemption to keep operating from the hospital; then the department had told him/his trust that singles do not comply in and out of that pad.

Why else would they feel the need to apply for an exemption?

Also, as much Hugh Jones is not always the most pleasant of human beings; one has to think quite hard as to why he would refuse, as operator of the A119 for the Taranaki trust, to continue to operate out of the hospital pad following the Director of CAA delivering his letter.

But, you are right I have made an assumption, not stated a fact.

However, I agree whole heartedly with you about the level of knowledge - or lack there of - about these matters of both the media and some trust managers/boards/chairs.

The level of their ignorance is a mix of sad, scary and funny all at the same time.

TK
(edited for typo)

Te_Kahu
11th Jul 2010, 10:18
Kiwis raise $1.5m for rescue helicopter

Despite tough economic times, New Zealanders have set a record with donations to this year's Westpac Rescue Helicopter Appeal.

Almost $1.5 million was donated, and organisers of the appeal say every cent will go to the 16 rescue helicopter trusts nationwide.

Rescue helicopters undertook almost 5,000 missions last year, each costing thousands of dollars.

- NEWSTALK ZB


One can't help but wonder if the public would have been quite so generous if they knew what sort of amateur hour some of these trusts are.

TK

Te_Kahu
28th Aug 2010, 21:15
The increasing farce which is the operation of the Phillips Rescue Trust has gone to a new level.

A friend of mine was at Palmerston North Hospital the other day and witnessed their AS350fx depart the pad using a Cat A profile i.e. backing up and then flying away. Hard to fathom the rationale of that anywhere, let alone out of a built up urban environment.

chopjock
28th Aug 2010, 23:59
A friend of mine was at Palmerston North Hospital the other day and witnessed their AS350fx depart the pad using a Cat A profile i.e. backing up and then flying away. Hard to fathom the rationale of that anywhere, let alone out of a built up urban environment.

Perhaps the pilot considered the engine and transmission would be at it's greatest risk at max power (during take off with no wind) and a Cat A profile gives you somewhere to crash back into if the engine fails. It will also give a 40kts departure speed(assuming no engine failure) from the pad which would be better than a towering take off with little or no airspeed.
In other words he might be trying to keep his max risk to the pad area.

JimL
29th Aug 2010, 10:30
Oh dear chopjock - that is really amusing even for you.

What exactly is a CAT A procedure for a single?

A twin with a failure on the back-up and with the second engine running struggles to get back to the pad. How on earth could a single do it with negative airspeed.

If you are taking off over a built-up area in a single, that's where you are going if the engine fails.

Jim

chopjock
29th Aug 2010, 11:06
A twin with a failure on the back-up and with the second engine running struggles to get back to the pad. How on earth could a single do it with negative airspeed.

If you are taking off over a built-up area in a single, that's where you are going if the engine fails.


Obviously, but if you fly a Cat A departure profile in a single,assuming no engine failure and you don't back out beyond the perimeter, you will be departing the pad area with translational lift, much better than leaving the pad at below translational speed with a towering take off.

That's the rationale behind why I would do it anyway.

Is it any more dangerous to fly out this way?

JimL
29th Aug 2010, 15:08
I have no knowledge of the operating site or its obstacle environment but, if the NZ CAA requires it to be flown in PC1, we might make the assumption that it is contained within a congested hostile environment.

Flying out of any operating site in a congested hostile environment (in a single) puts the helicopter into the exposure area - there is no way to sweeten the pill.

A helicopter certificated in Category A may or may not have a helipad procedure; if it has, it could be vertical, back-up or sideways but it will be exclusively provided by that manufacturer for that helicopter along with the profile, obstacle clearance criteria and mass limitations - all of which have to meet the requirements specified in the certification or operational rules.

If there is any wind at all; flying backwards in a single would be the equivalent of a transition downwind (and backwards), followed by a further transition from downwind, through a zero-wind condition and eventually into wind - all undertaken inside the HV curve.

This would require more power than a normal transition or a towering take-off and might take the helicopter outside of its control envelope. On a risk assessment basis, there appear to be few gains but it does introduce number of unquantified (by the manufacturer) hazards - including an extended period within the HV curve.

Jim

Shawn Coyle
29th Aug 2010, 19:23
JimL:
I recently had my helicopter education improved by an old-timer - the subject was departures from confined areas. Liked what he said so much that I wrote it up for Vertical magazine.
Basically, it involved backing up from the front of a confined area in order to keep the barrier in sight, and allow a known flight path back to the ground in the event of an engine failure (or lack power available).
Same logic might be used here - backing up will put you in the HV curve, but with a known landing spot in sight that's ahead of you. And evidently there is very little cyclic movement needed to get back to the spot - just lowering the collective will also move you forward towards the spot.
Interesting technique!

The Nr Fairy
29th Aug 2010, 20:29
Not quite a single engine failure, but I know of a a freewheel unit failure in a popular twin type some years ago, which killed three.

ricksheli
14th Nov 2010, 07:05
Comments on the following Video, single engine doing joy rides ( flight every 5min over 4hr period), within a built-up area.

Hl5k3Uz02HI

Earl of Rochester
14th Nov 2010, 08:59
Not entirely uncommon in high wind conditions when translational lift can sometimes be achieved in the hover and when wishing to build height in order to transit terrain inhospitable to autos.

Its really about power. If its there, that's a good sign (ie: a/c not operating at MUAW) and the procedure would be to clear the h/v curve asap!

Earl

DennisK
15th Nov 2010, 23:19
As a stiff-arsed Brit ... can I put in my two pennorth! When teaching the UK's CAA Ex 26, I teach as SOP the twin engine rearward lift technique, keeping the ELG nicely below til sufficient height is available to secure translational lift before climbing away ... so at least some manoeuvreability and choice of ELG becomes available in the event of an engine malfunction. I also never forget that when flying two engines, the chances of an engine malfunction are doubled!! Multi engines are fine and absolutely necessary for utility ops but we shouldn't forget that the power plant is just one component that keeps us airborne. We also really need two M/R hubs, two MRGBs, ditto T/R transmission & blades and swashplates ... but not likely to happen. PS. I'm still waiting for my first EOL after 1 year & 7 months in the air!

Festive good wishes to all Pruners. Dennis Kenyon.

Savoia
21st Apr 2011, 12:03
.
I sometimes wonder just how many incidents have ocurred where a twin has suffered the failure of one of its engines and subsequently gone on to perform a safe landing.

Twins certainly seem like the sensible/responsible thing to do and are now well established in the commercial domain but, like Dennis, I also wonder about ..


.. we shouldn't forget that the power plant is just one component that keeps us airborne. We also really need two M/R hubs, two MRGBs, ditto T/R transmission & blades and swashplates ...


Thinking of North Sea incidents I seem to recall remarkably few directly attributed to powerplant failure whereas there were numerous involving 'other' component failures!

Sav

AnFI
27th Jun 2014, 11:01
er - the point is they do have engine failures sometimes but the consequences are rarely terminal. The consequences need to be bad to justify 2 engines. Another piece of evidence in favor of singles.

"No one was hurt."

SilsoeSid
27th Jun 2014, 13:56
AnFI
Another piece of evidence in favor of singles.

"No one was hurt."


... unlike the other single engine related crash that has happened this month, recently posted about on rotor heads, where significant injuries were sustained and where everyone on board was injured to some degree! :ugh:

hueyracer
27th Jun 2014, 15:07
Shall we now pull out all the crashes with the S-92´s, the 332´s, the AW139´s and all the other multi-engine aircraft that went down in the past 2 years, killing everybody on board?

An aircraft is as good as the engineer that maintains it, and as good as the pilot that operates it in its limits-no matter how many engines it has...

jayteeto
27th Jun 2014, 16:01
I was only looking for a bite, wow! That worked.
In reply to AnFi, yep, no one injured this time. A twin would of course have just flown home.
To Hueyracer, were all those caused by single engine failure?
Thought not.

hueyracer
27th Jun 2014, 16:04
Exactly-that´s the point…

jayteeto
27th Jun 2014, 16:42
It's a helicopter, when they go wrong it can be exciting. However you should give yourself every chance you can.
In 7000 hours, I have had one crash and two engine failures, all in Pumas. The crash was mechanical drive shaft failure (not engine) into the jungle. The engine failures were both in truely appaling weather, one was in 65kt surface wind 20 miles out over the northern English Channel and one over NI with a 300' cloudbase and 45kt wind. That would have been splash and crash in a single. Nobody will EVER convince me that a single is just as safe....... EVER!!

GoodGrief
27th Jun 2014, 19:08
The engine failures were both in truely appaling weather, one was in 65kt surface wind 20 miles out over the northern English Channel and one over NI with a 300' cloudbase and 45kt wind. That would have been splash and crash in a single

You wouldn't be out there in those conditions in a single...:ugh:

MightyGem
27th Jun 2014, 19:14
You wouldn't be out there in those conditions in a single.
You could have been in the second one. Delete Puma, insert Army Gazelle.

Gemini Twin
27th Jun 2014, 19:37
Wow this developed into a twins v singles real fast!


You are correct in thinking that this would not have happened if it had been a twin because low budget aviation units like Mesa PD would never, ever be able to afford a multi engine helicopter.

Soave_Pilot
27th Jun 2014, 20:11
Let's get all the single engine helicopters and airplanes out of the sky then!! :ugh::ugh::ugh:

jayteeto
27th Jun 2014, 21:26
There is a place for everything, including singles, but operating in the police/ambulance role over urban/hostile territory is foolish. Cheap, but foolish. This is probably why Sid posted in the first place. Accidents will always happen, no matter how many engines, but try to reduce the risk as much as possible. I totally understand those who support the concept, especially if the alternative is nothing at all. My ONLY beef is people coming forward saying that it is just as safe. It isn't, the end.
If you come forward and say that the risk is higher, but acceptable to the authorities, then game on. In the minefield of litigation post accident, the lawyers would tear apart any such statement.
Let's call a shovel a shovel.

diethelm
28th Jun 2014, 18:05
At the end of the day, it is all an economic trade-off. In Maricopa County, where Mesa is located, the City of Mesa has 3 ships (now two going back to three by august), Phoenix has 12 (1 is a twin), Maricopa County Sheriff has 4, Arizona DPS has 4 and all the other cities are talking about getting their own.

So, you take 22 single engine ships in tight budgets and you covert them to twins in acquisition, training and operating costs.

If you look at the total number of accidents/incidents relating to engine failure in the last twenty years resulting in an autorotation, the grand total is one encounter. This one.

If you assume public safety money is fixed, you can cut the ships or hours in the air and do a cost/risk analysis of what happens without a ship in the air. Is an officer shot, do they lose a suspect, is the high speed chase worse? Or, do you cut the number of officers on the ground?

With respect to police air units, the American system has done that analysis and come to the conclusion that factoring in risk versus reward, singles are the way to go.

AnFI
28th Jun 2014, 22:53
when the engine fails in a single you have to land, sometimes messy, very occassionally fatal.

when the engine fails in a twin, sometimes it is non-eventful, sometimes it is an accident and sometimes fatal.

BUT sometimes in a twin you also have a fatal accident that you would not have had in a single, from other causes. the critical components have to work harder to pay for for the occasional imunity. Less engine failure accidents paid for by more gearbox/tailrotor/freewheel units/fuel systems/ performance cost/ tail boom failures/ 'pilot error' (shut down wrong engine, confusion etc) etc

All things will happen in aviation to some extent.

PROPORTIONATE REGULATION does not call for twins.

the sums don't add up, gazelles just did not have an engine failure rate that justified twins FULL STOP

SilsoeSid
29th Jun 2014, 09:09
I'm hearing an argument that suggests that all air ambulance & police helicopters should be Robinsons. :eek:

Now, just where does that line get drawn?

AnFithe sums don't add up, gazelles just did not have an engine failure rate that justified twins FULL STOP

Lol, sometimes AnFI (really!) your posts are really quite laughable.

ShyTorque
29th Jun 2014, 09:43
Trying to convince some exponents of the "single engine is best" theory is pointless. Even though they have little or nil experience of multi engined aircraft, (and probably little prospect of flying them which may explain their stance), they think they know better than folk with a far broader experience .... and better than the regulatory authorities.

Some obviously fail to realise, or choose to ignore, the fact that all pilots now flying twin engined helicopters began their careers flying singles.

jayteeto
29th Jun 2014, 10:20
GoodGrief, why would singles not be flying in those situations? Why the banging head symbol? I just don't understand that one.......

GoodGrief
29th Jun 2014, 10:39
The engine failures were both in truely appaling weather, one was in 65kt surface wind 20 miles out over the northern English Channel and one over NI with a 300' cloudbase and 45kt wind.
GoodGrief, why would singles not be flying in those situations? Why the banging head symbol? I just don't understand that one.......

1. Self preservation.
2. Common sense.
3. 20NM out at 65kts wind. What happened to 'autorotation to shore'? And the sea state in that is ? Floats wouldn't really help now, would they?
4. 300ft cloud base at 45kts. You'd be buzzing around at 200ft or even at tree top level? What happened to the 500ft rule?

Maybe I'm too much of a coward and know to say 'NO'.

C'mon, you want to stir the pot ?

chopjock
29th Jun 2014, 10:48
GoodGrief

What happened to the 500ft rule?

500ft rule? what 500ft rule?

jayteeto
29th Jun 2014, 10:59
Common sense?? When you have to get a job done and it is within the aircraft limits, why not??
Auto to shore, I will accept that, so singles will limit how you operate if there are any areas of water??
Common Sense?? Matey, see above.
What 500ft rule??

Ok then, lets 'stir the pot' whatever that means.

blackdog7
29th Jun 2014, 14:42
Engine failures are debated as theoretical events and dismissed with statistics-except to those of us who have had an engine failure. It then becomes the primary consideration in whatever you do for the rest of your life.

MightyGem
29th Jun 2014, 19:57
What happened to the 500ft rule?
Doesn't apply to the Military, which this was.

AnFI
29th Jun 2014, 21:49
ss:

"AnFi Quote:
the sums don't add up, gazelles just did not have an engine failure rate that justified twins FULL STOP
Lol, sometimes AnFI (really!) your posts are really quite laughable."

Excuse me! Are you actually saying something or just trying to discredit? - the fact of the matter is Gazelle losses through engine failure were negligable - Lynx losses through engine failure have not been - the utility of the gazelle was huge and it's bang per buck for the tax payer was high.

I know of three (UK MIL) Lynx engine related accidents although i know of no (UK MIL) engine failure accidents (not that I'd be surprised if there had been).

Not to mention the extreme downside of performance for 30yrs for lynx caused by carrying spare engines, instead of useful payload.

Substance, not just rudeness. SS!



Huey Racer : "Shall we now pull out all the crashes with the S-92´s, the 332´s, the AW139´s and all the other multi-engine aircraft that went down in the past 2 years, killing everybody on board?" good point , carrying two engines does not seem to have delivered anything like 100,000 times lower loss rate. Irritating when the facts get in the way of a determined ignorant theory.

SilsoeSid
29th Jun 2014, 22:14
Oh AnGi, there you go again!

Are you really suggesting that the Gazelle could have fulfilled the role that the Lynx was brought in for!

As I said before, your posts are laughable.

Instead of saying 'you know of ....' please post links
(Did you see what I did there!)

SilsoeSid
29th Jun 2014, 22:20
and what does;

I know of three (UK MIL) Lynx engine related accidents although i know of no (UK MIL) engine failure accidents (not that I'd be surprised if there had been).

... mean?

I'm not going to trawl through the relevant reports, but your argument is flawed when your side is looked at sensibly and not restricted within certain parameters to meet your needs;

http://aviation-safety.net/wikibase/wiki.php?id=46173

AnFI
30th Jun 2014, 06:52
"Last edited by SilsoeSid; 29th Jun 2014 at 23:31. Reason: link to end silly irrelevant restrictive side of discussion"

Err too many sherbets?

Your example is of an obscure user, unlicesed to fly, NOT killing themselves!!
It is possible to find a Gazelle fatal due engine, but you have to go a long way back in time and far out in geography.

The reason to use the UK MIL is that the other circustances are controlled, avoiding side issues like whether the people had licenses.

It is not easy to provide a list of UK MIL engine related crashes in LYNX because it seems that the data is obscured. Your friend was killed in one, those nice chaps were killed in Afg, some other nice guys hit the water (both engines shut down, for some odd reason). Many ex-lynx drivers have told me of their accidents and close shaves. They don't appear to be documented:mad:.


SS; "Are you really suggesting that the Gazelle could have fulfilled the role that the Lynx was brought in for!"

Errr, No, obviously not.
The point was the engine related accident rate.
Not whether it could land on ships, or had a sliding door.

Imagine the high performance machine a Lynx could have been as a single.

terminus mos
30th Jun 2014, 07:34
AnFi

I thought that the double ditching, one fatal in the GM had shut you up for a while, evidently not.

The engine argument is one thing. Saying that components on a S-92 or EC225 are more stressed is garbage.

Twins tend to be better equipped and IFR capable. You can't really do that in a single if you actually want to carry anything.

SilsoeSid
30th Jun 2014, 07:55
AnGi;
It is not easy to provide a list of UK MIL engine related crashes in LYNX because it seems that the data is obscured. Your friend was killed in one, those nice chaps were killed in Afg, some other nice guys hit the water (both engines shut down, for some odd reason). Many ex-lynx drivers have told me of their accidents and close shaves. They don't appear to be documented.

As I say, laughable posts!

1.The outcome would have been worse if it was single engined.
"Crashed on emergency landing after cockpit had filled with smoke. Caught fire and burnt."

2. Cause not yet known.

3. The 'for some reason' the engines shut down was because they ran out of fuel having been misdirected on the way back to 'mother'.
"During Exercise Marstrike05 is was misdirected back to HMS Nottingham. It ran out of fuel 41 miles from the ship and made a controlled ditching alongside MV Wilhelm Schulte in Indian Ocean 120 miles off Oman. It sank in 2,800 meters of water but the crew were rescued safely"



Aviation Safety Network > ASN Aviation Safety WikiBase > Lynx (http://aviation-safety.net/wikibase/dblist.php?AcType=LYNX)


It is possible to find a Gazelle fatal due engine, but you have to go a long way back in time and far out in geography.
A long way back (2011 fgs!), but not as far back as your Lynx examples, and with you mentioning Lynx incidents in Afghanistan & the Indian Ocean, how does Geography affect this discussion?

ASN Aircraft accident 20-AUG-2011 Aérospatiale SA 342L1 Gazelle L611 (http://aviation-safety.net/wikibase/wiki.php?id=138065)
ASN Aircraft accident 19-JAN-2010 Aérospatiale SA 342K Gazelle CN-AIP (http://aviation-safety.net/wikibase/wiki.php?id=72156)
Etc

Aviation Safety Network > ASN Aviation Safety WikiBase > Gazelle (http://aviation-safety.net/wikibase/dblist.php?AcType=GAZL)

SilsoeSid
30th Jun 2014, 08:29
AnGi;Imagine the high performance machine a Lynx could have been as a single.

Wow, even more high performance than the Worlds fastest helicopter! :ok:

chopjock
30th Jun 2014, 08:38
Wow, even more high performance than the Worlds fastest helicopter!

Well they took out all the spare seats and made it as light as possible I believe. Imagine how much lighter it would have been if they could have taken out the spare engine and all the fuel required to power it too.:}

OvertHawk
30th Jun 2014, 09:04
In 25 years of flying around in helicopters, i've met numerous people (and i'm one of them myself) who have said "and if that had happened in a single we'd have been stuffed".

I've never met anyone who said "If i'd been in a twin we'd have been stuffed".

Will two engines always save you? No.
Are two engines more expensive? Yes.
Does having two engines increase the statistical likelihood of having one of them fail? Yes, of course.
If you have an engine failure in a twin do you have a chance of flying away from it? Yes
If you have an engine failure in a single can you fly away? No

Thomas coupling
30th Jun 2014, 09:27
I love the comment made about how fast the topic of conversation has changed to Singles Vs Twins.....and then you notice that the gap between posts 49 and 50 is.....4 years!!

Meanwhile back at the ranch....Most here are talking from an insiders perspective (obviously!) because we are all passionate players in some shape or form...but...remember this: two types of people run this world: Lawyers and accountants. It is they who make the final strategic decisions because they are able to stand outside the box and determine if the operation will succeed or collapse.
They have determined that on the whole, in the round, at the end of the day - singles beat twins hands down for cost effectiveness. SAFETY really does come second even though the opposite mantra is shouted from the roof tops (this is so that the industry can be seen to be PC).
Example:
15 years ago the FAA and the (now) NTSB came to the conclusion that the design flaw in the 737's rudder screwjack mechanism was cheaper to resolve by paying out to all the deceased familes of those who crashed or would crash in future; compared to grounding the entire global fleet and replacing said defect.
In the cold light of day, these two organisations determined that the final cost to insurance companies of the death of a US citizen was: (1999) $186.
They did the maths. looked at the probabilities and the dollar won - hands down.
Same goes for modern jets flying over the oceans of the world on ONE engine.
RISK = frequency x outcome.

And so it came to pass that on the whole it is better for the organisation to fly singles because the impact of losing one single and its entire crew is marginal/minimal.
UNLESS you are onboard at the time.
I had the inlet guide vanes on my SeaKing (S61) shut in the hover over a sea state 7.
I had a compressor blade go in my AS355 over the middle of a city.
I have had compressor stall in another AS355 incident.

In any or all of those - I suspect my chances of being here today would have been seriously curtailed if those incidents had been on singles. Thus I am biased but in the big picture, my subjective overview is lost in the noise that is corporate diligence and the bottom line: money.

Try responding to this thread thru the eyes of an accountant or lawyer?

AnFI
30th Jun 2014, 09:32
terminus
much truth in what you say with a little muddled thinking also:

2 ditchings in GoM: 1 was just an ordinary landing due Engine Failure - proving that 2 engines were not required in that case.
The other I don't know the cause of but it appears that it "struck the water" , maybe engine failure but unlikely if you have enough energy to 'strike the water' (and damage the helicopter so badly) then you probably have enough energy to flare and land gently. Was the second one and engine fail? Anyone know yet?


"Saying that components on a S-92 or EC225 are more stressed is garbage."
It is true that it becomes less important at bigger scale. It is very true for the lightest twins and progressively less significant for larger machines where the payload wasted (or invested, depending on how you see it) by carrying spare engines becomes a smaller proportion.

but if you spend payload on something not neccessary then it does cost you margins elswhere.

For example: If it were mandated to carry 500kgs of Lead (Pb) then clearly this would impact not only the margins of other critical components but also cause more time exposure of tailrotors (etc) per payload.mile, fuel reserve etc etc
If the 500kgs of Lead were useful to the extent that it was worth the downside then it would be an improvement. So it is not garbage , although it may not be highly significant.

terminus mos
30th Jun 2014, 09:42
The other I don't know the cause of but it appears that it "struck the water" , maybe engine failure but unlikely if you have enough energy to 'strike the water' (and damage the helicopter so badly) then you probably have enough energy to flare and land gently. Was the second one and engine fail? Anyone know yet?


Muddled thinking, only in your mind. My thinking is clear.

There are multiple reasons it may have "struck the water" and I agree that engine failure is not necessarily the most likely scenario. Same operator, 2 in 2 days, not good. Even the "successful" ditching is a problem, now you have people floating in a raft requiring rescue, way outside most OGP company risk profiles.

It may have been a mechanical failure, surely unlikely in such an unstressed machine with only one engine? It may have been crew error?

But, had it have been an IFR twin, it would have probably been operated in such a way that contact with the water would be minimized.

pilot and apprentice
30th Jun 2014, 10:43
1. Self preservation.
2. Common sense.
3. 20NM out at 65kts wind. What happened to 'autorotation to shore'? And the sea state in that is ? Floats wouldn't really help now, would they?
4. 300ft cloud base at 45kts. You'd be buzzing around at 200ft or even at tree top level? What happened to the 500ft rule?

Maybe I'm too much of a coward and know to say 'NO'.

C'mon, you want to stir the pot ?

The argument in question (from AnFI and others) is that there is no justification for a single/twin distinction. Therefore, those operations would be equally safe, and acceptable, in a 206 (or 205, 214?, if you need more seats) as a Puma. So yes, regardless of why one was in those situations, they are relevant.

Interestly, as a contractor for a military customer, they were adamant we had 2 pilots to carry pax, but as long as the performance requirements were met the number of engines was unimportant.

Ultimately, all these rules are legacy items. Relics from decades past, fatal accidents not forgotten, and group perception. The fixed wing industry has saddled helicopters with reams of inappropriate legislation (such as the emphasis on numbers of engines as the penultimate measure of a safe design) and we will have to deal with it for some time! But yes, I still prefer to fly a twin. OEI RTB is less stressful than an auto. I've done both, having lost the use of an engine in the 22/500/412/76/332.

Solely for AnFI: if we are mandated to carry 500 lbs of lead by regulation, and the MGW of the type is unchanged, then I lose only payload available and the components are no more stressed. If a design is changed to increase MGW by 500 lbs to compensate then yes, there is more stress (and likely new components). Designers face many hurdles and the number of engines is one tool in the arsenal of compromises.

Finally, all the stats in the world trolled from endless google searches won't change the fact that it is all bu!!$hit. A pilot of a single is flying his aircraft with a different mindset and in a different role than the pilot of a twin, for a multitude of reasons (regulation, cost of operation, environment, sanity) and so the stats are heavily slanted!! Happily [hopefully] the ones who make the real decisions understand this LOL!

Fly safe, make sound decisions, and come home at the end of the day!!

AnFI
1st Jul 2014, 14:59
Hi P&A

good points but the 500lbs of lead does because the payload is cut and so either more trips need to be performed to provide the same transport capacity. OR another way to look at that is: If the 500lbs of lead is removed but the payload is not increased then the critical components are working less hard. a bit perverse true, but true non the less...

They could run Twins with less 2 pax and achieve a similar effect Cat2e could possibly remove the e if only ONE pax were carried - but would it be worth it in extra runs? 10 runs with 1 pax or 1 exposed run with 10 pax?

AnFI
2nd Jul 2014, 22:30
I need two engines in my car - I'm worried about being stuck out on the hard shoulder if the engine stops.... Doh!

terminus mos
3rd Jul 2014, 07:22
I need two engines in my car - I'm worried about being stuck out on the hard shoulder if the engine stops.... Doh!

Wow, AnFI, that has to be the most idiotic comment I have ever seen on Pprune. Obviously the concept of any system redundancy is completely lost on you.

Off to the "ignore" box for you.

aeromys
3rd Jul 2014, 09:39
Interestingly, an armada of 8 French TV helis popped into Redhill yesterday, for a top up on their way from France to Yorkshire for Le Tour, all single Squirrels. Should be fun when the race gets to London !

HeliHenri
3rd Jul 2014, 12:10
.
8 French TV helis /.../ all single Squirrels

That kind of single ? :

All (2) helis with cameras are twin ;)



http://nsa33.casimages.com/img/2014/07/03/140703021149597204.jpg (http://www.casimages.com/img.php?i=140703021149597204.jpg)

Boudreaux Bob
3rd Jul 2014, 12:40
TC suggests the "Almighty Dollar" is behind the FAA and NTSB decision on the 737 Rudder problem.

Have not many here argued that is the exact same calculation the Oil Industry and Helicopter Industry enter into when decisions re Safety are made?

When the Certifying Agencies (FAA, CAA, EASA, MOT, CASA) use a definition of "Most Unlikely" (or whatever the term is for a calculation of an event occurring) that would absolutely and without doubt lead to the destruction of the aircraft (killing the occupants), are they not doing exactly the same?

It goes on everyday in this World wherever Helicopters are flying.

If you climb into your Cab at Aberdeen, a PAS Unit, or in the GOM, you are accepting that concept yourself as you know Helicopters are not a perfect science and never will be. You gamble your Life for that pay check.

So how about all y'all quit the Finger Pointing.

aeromys
3rd Jul 2014, 13:20
Ah, apologies, didn't see those two arrive. So the singles with cameras are.... what? ;)

Redhill (https://twitter.com/NPAS_Redhill/status/484429842591780864)

Edit - I've been corrected, the pods on the singles are Relays for the downlink, ooops

HeliHenri
3rd Jul 2014, 13:54
.

Edit - I've been corrected, the pods on the singles are Relays for the downlink, ooops

;) Yep, and the others single are for VIP flights.

.

AnFI
3rd Jul 2014, 23:05
Fortunately Term Mos can't read this:

He said "Obviously the concept of any system redundancy is completely lost on you."

but he really is an ingnorant fellow .... redundancy is a concept but reliability of a simplex system is better, obviously.

use the weight spent on a 'redundant' (the clue is in the word) system to make the single system unlikely to fail, then the 'redundant' system (that is REDUNDANT and just consuming payload) is not required - doh!

how much 'redundancy' do YOU have in your car? Is it reliable?

ShyTorque
4th Jul 2014, 00:06
but he really is an ingnorant fellow .....

Now that's a schoolboy howler if ever there was one! :D

AnFI
4th Jul 2014, 07:01
hmm that is baad but just a slip of they keybored in this case

that is part of the problem - the world is run by people who can spell at the expense of people who understand Noether's Theorem