police incident [Archive]

SASless

9th Oct 2002, 04:19

Lets go back and see how many twin engine UK police aircraft have crashed ....seems like a couple within the past year or am I mistaken? The Two engine smartass remarks we hear from the eastern end of the saltwater divide everytime a single engine helicopter winds up in the scrap yard following a forced landing does get old......at least we don't say things just as silly when the UK Po-leece stuff one into the ground for some other reason.

I swear by two engines but also understand that with most of these light twins....the good engine is only going to take us to the scene of the crash.....and before you start on the CAT A bovine feces.....no we don't operate at those weights. At some point.....reality has to take over and determine what we do in flying.....the point about a single tail rotor....heck...just lose one part of a tail rotor blade.....and you will find yourself in a much worse predicament than a mere engine failure (be it on a single or multiengine helicopter). It was not so long ago.....during the search for the two young girls that were murdered....that I observed live and on international television.....a UK police helicopter hovering along with a picture taker stood outside the cabin......an engine failure there would have been most exciting....definitely not Cat A profiles being used then.

The Police have a dangerous job to do....and my hat is off to them....especially the US Cops that fly around in the singles....I am much too old for that but that doesn't mean it cannot be done just as safely as with a twin. The majority of the engine failures on singles in the Gulf of Mexico have been due to contaminated fuel.....and that would kill two engines just as quickly as one.

Think back to the North Sea fatal crashes....just how many of those were due to an engine failure? We have seen tail rotor failures, main rotor failures, pilots stuffing the aircraft into the water....but I personally cannot recall a fatal accident stemming from an engine failure though there very well might have been one.

GLSNightPilot

9th Oct 2002, 06:43

Single-engine aircraft aren't killing people offshore, anywhere. According to the International Association of Oil & Gas Producers, for the period from 1994-1998, the number of fatalities worldwide due to engine failure in helicopters was exactly zero. For airplanes, the number is much higher, & engine failure is the biggest cause of fatalities. For helicopters, it's FITWO (Flight into Terrain, Water, or Obstacles, what the US calls CFIT), midair collisions, & other mechanical failures. I don't recall a single fatality in the Gulf of Mexico in the last 20 years due to engine failure, & there are far more single-engine aircraft flying than twins. Fatalities yes, but not from engine failure.

See for yourself: Safety performance of helicopter operations in the oil & gas industry (http://www.ogp.org.uk/publications/_summaries/300.html)

I like twins, but the economics don't show the necessity, & don't kid yourself, it's always economics. The only bearing safety has for corporations is economic - if they make more money (or lose less) by being safe, they will, but it's purely economic. Money talks, & everything else walks. It's wrong, but that's the way it is.

John Eacott

9th Oct 2002, 07:04

Widgeon,

To answer your original query, S(ouls) O(n) B(oard) was (IIRC) the normal abbreviation in some parts of the world before POB became the 'standard'.

Ascend Charlie

9th Oct 2002, 09:45

The NSW Police have been operating singles since 1979, and have only lost one , coming from an N2 bleed air problem running the engine down to idle. They plopped into the sea and all OK. They have also operated several twins - a new BK117 A4, which was operating for only 6 months when an engine cowl went through the rotor resulting in a semi-controlled ditching. Machine written off, but crew OK.
Next twin was a used twin Squirrel. Lasted a bit longer, but also had a swim when the same pilot as in the BK was swamped by a wave while rescuing a fisherman off rocks.

So, 2 spectacular accidents for twins, which made zero difference by having 2 engines, just made the crashes more expensive. The single accident would not have happened if it was a twin, but our skinflint government wouldn't come up with the money for more twins, even if they could be justified.

neverinbalance

9th Oct 2002, 11:33

The British Army have been operating single engine helicopters over Belfast since 1970. Could someone enlighten us as to the number of engine failures? (Zero me thinks).

Q max

9th Oct 2002, 12:47

The arguement for twins is (almost always bogus).

The increased risk of running (and carrying) two engines needs to be less than the probability of an event occuring where having two engines might help.

The small slivers of time when having two engines might help rarely justify the risks.

Just curious - but what does happen when all power fails in a twin ( fuel, drive system etc )?
How do people expect the driver to land this heavy brick - the pilots are not trained for it (no EOL in twins) and the machine does not do it very well !! In a single (generally more reliable) the pilot can land uneventfully in most cases.

1 minute per hour certainly would not justify having a twin!

....and many other points (European protectionism, jobs for the boyz etc)

john du'pruyting

9th Oct 2002, 14:04

The benefits or not of 2 donkeys is pretty pointless. Here in the UK, we are stuck with them and that is probably the way it is going to stay. I wouldn't get too wound up by TCs comments I assume they were designed to elicit exactly the response that followed (At least I hope so, I have met the bloke and in the flesh he doesn't seem as pompous and patronising as his comment can sometimes suggest;) ). There are times when I wish we could field a fleet of aircraft as you do across the pond (any pond, east or west) and the only way we could do that is if we were to operate singles. That said, after all this time with a pair of P&Ws finest above (behind!) my head I think I would find it quite nerveracking to go back to a single. Finally, remember we've got a smaller country than you americans (australians,canadians,..., zambians:cool: ) So.. we've had to make all our streets narrower to fit everybody in. Hence, less space to auto into should (a/the) donkey stop.
PS. Two engines...bigger aircraft...more donuts!:D

HeliMark

9th Oct 2002, 17:52

Being a police pilot, guess I'd like to comment on this a little.

First off, for most police departments on the other side of the pond, they do not "patrol" with their helicopters. They do not fly as often, or cover the area that some do over here. An example being, that my department covers 4,000+ sq. miles of area. The only way to provide service is to have as many ships out as possible. Economics dictate singles due to this. We poactively are out looking for "crime" and assisting the ground units. During a shift we average a total of 5 hours in the air.

Our fleet puts on about 10,000 hours a year, 99% of it in singles. The only engine failure in a turbine was about 12 years ago, and the pilot knew the engine had problems, but kept flying it (for several days prior, he admitted it was having compressor stalls) until it quit. We operate from sea level to 9,000 feet with temps from below zero to 40c+. Lots of IGE and OGE hovers also due to search and rescues. Pretty good record for a single.:)

I would love to have a twin, but statistics just do not prove it out in my job. And as far as smaller streets, in the city here, it will not be any better doing an auto onto the street.:(

And our training ship (MD500D) that we practice all of our full touch down auto's has 17,000 hours.:eek:

Draco

9th Oct 2002, 20:48

....is it purely coincidence that the three NSW Police helicopters mentioned above ended up ditching?

And as regards hovering over Belfast in a single, after watching what happened to those two Signals corporals who blundered into an IRA funeral some ten years ago, I would want every safeguard I could get. Hats off to the army pilots.

SASless

9th Oct 2002, 23:39

Draco....

Think about our guys working over Mogadishu with Blackhawks....even sophisticated helicopters can have a very bad day every now and then. It wasn't engines that caused that bit of excitement either....just some minor FOD to a couple of tail rotors. RPG's really are small things right?

There are worse places to have forced landings than in major urban areas.....think of being anywhere in Saudi.....know how far it is to a decent pub from anywhere there?

Besides....did not Bill Clinton bring peace to Northern Ireland or did his spin doctors exaggarate his accomplishments a wee tad?

Notar fan

10th Oct 2002, 01:42

It wasn't engines that caused that bit of excitement either....just some minor FOD to a couple of tail rotors. RPG's really are small things right?

Whatever about that extra engine!!!!!!!
Now a Notar system..................there's a safety feature worth spending the money for.

Nick Lappos

10th Oct 2002, 03:23

Qmax,
All certified helos have to demonstrate full autorotative capability at all altitudes and gross weights, tilt rotor proponent's opinions to the contrary notwithstanding. This assures that the auto in a twin is do-able, and that even though the odds are very low, a dual engine failure will be survivable.

They may be bricks, but they are autorotatable bricks!

Steve76

10th Oct 2002, 03:36

Any helo with an operating engine above 10ft is a brick. 1,2 or 3 engines make no difference to an auto.:cool:

SASless

10th Oct 2002, 04:00

Nick.....you got me cornfused once again....it must be the years of ridiing around in something that couldn't decide which rotor head was supposed to be in front!

When you say the "odds are very low".....to what do you refer please.....the risk of a dual engine failure (and that would include all catagories...dual simultaneous, one followed very closely by the other, and a second engine failure after a previous one some time in the past but subsequent) .....or do you mean the resulting autorotation has a low odds of success?

I think I rightly assume you mean the odds of having to do an engines out autorotation is very low.

I must state the thrill one gets doing those is quite significant......and note for all and sundry gathered here.....never...never....trust a student to move any switches without watching him oh so very closely! The fuel valves are clearly marked in a Chinook...and oddly enough are placed on the correct sides of the panel....#1 on the left....#2 on the right....just like all sorts of other switches.....the dislexic rascal promptly shut off the wrong fuel valve....and with a Chinook...that quite promptly results in a deathly silence save the IP's blubbering!

The second occasion was when one engine wound down with a governoring failure.......on approach to a hover only mountain top LZ....Gia Re mountain near Xuan Loc....and the other one went into compressor stall just as we were in the very last stages of the approach to a hover with a sling load.....earned the callsign "Brown Shorts" that morning! It is amazing what the ol' Hook can do when you really need some help! Bleed the rotor rpm low enough and the gennies drop off line.....and even door gunners will swear off hard drink as part of their negotiation with the Almighty!

[email protected]

10th Oct 2002, 08:27

SASless, I think the Mogadishu episode had less to do with engine performance than putting themselves firmly in the threat band without actually assessing the threat. Strangely the funny little black guys had something slightly more dangerous than a piece of sharpened fruit (sorry Blackadder) to throw at them.
'They can't hurt us, we're Americans' hut!hut!hut!

Thomas coupling

11th Oct 2002, 11:37

sorry I spoke..............:p

Got the juices running though:D

That's more like it.

Up & Away

11th Oct 2002, 12:08

The point, I think, you were making was correct.

If engine failure was the cause.... then a second engine running would have eased the situation..

I don't think you were argueing for of against single/twin operations. Each are correct for the different situations.

Well feel better now.

Hoverman

11th Oct 2002, 12:26

TC
Does that mean all that cr*p you wrote on the EMS htread about always keeping rigidly to the rules on EMS ops was also a windup to get the juices going?:confused:

StevieTerrier

11th Oct 2002, 12:43

I think you are all missing the point about one engine vs two. The extra engine is included purely to make the pilot appear even more god-like than he is. Two engines = two lots of dials in the pointy bit at the front.

When I show people round my twin they dont say "wow its got two engines", but "wow - look at all those dials". (It has a full set of co-pilots instruments too).

All Rotorheads know that what they are really saying is "wow you must be some kind of brilliant guy to be able to fly that".
;)

Now where can I get my hands on an EH101?

PS Tip for all you R22 jocks out there. Halfords do a three-instrument pod with velcro backing that you can pop on top of the console. You can then have an ammeter, voltmeter and standby manifold pressure gauge up there instead of that useless Garmin 150 box. Looks the business. Alright!!!

Thomas coupling

12th Oct 2002, 01:12

Hoverman: Sorry you see it that way re the EMS thread. Thought you were someone who had a mature head on those shoulders of yours. Never mind, takes all sorts eh?

I don't see the problem with this 2 engine situation: I didn't mention common drive train malfunctions, or any other systems malfunction. I simply said that this guy had a problem with his frigging block! It wouldn't have been a problem if it had happened to a Uk frigging police frigging helo...would it?

General question for all those S.E. drivers out there:

What do your crash cards say when you get a chip light?

Why is it that in all light twins you are required to shut the engine down, or atleast to F.I.

I have had two engine shut downs (surge and turbine blade disintegrate) in the last 6 years both of which were over a built up area. My predecessor had an engine flame out in heavy rain at night. How different it would have been with only one donk on board.....................

john du'pruyting

12th Oct 2002, 13:43

You never know TC, you could have been lucky...maybe your single would have had the working engine not the knackered one ;)

Thomas coupling

12th Oct 2002, 13:47

Q max

12th Oct 2002, 14:14

TC: "What do your crash cards say when you get a chip light?"

They say: "find the nearest convienient pub and make a normal landing."

Landowners permission NOT REQUIRED under these circumstances:p

How far are you supposed to fly with OEI ?

...and TC you are lucky you weren't over open land with no power wishing you were in a single and that someone had at least shown you how to make an EOL in your BRICK.

Nick L : How many pilots could actually perform an EOL in a twin? ... I am right that they are not actually practised/shown/taught? (quite rightly too)

GLSNightPilot

12th Oct 2002, 18:16

I've always assumed that the reason for shutting down an engine with a chip light was to save the engine from further damage - it's an economic, not a safety, issue. If you only have one, you keep running it until you can land, which is usually not that long in a helicopter. I don't know if this is universal, but I did autorotations in both the 412 & S76 while being checked out, & do them regularly in the sim in recurrent training. Lots of fun in the sim, since you don't get hurt when you prang it really hard. :D It's nice to be able to intentionally do something wrong & see what happens, without getting fired for it.

SASless

12th Oct 2002, 19:58

GLS...I know of a place where training captains appear to be above the law when it comes to tearing things up as a result of being boneheaded.....and at the Sim...they don't give you a two week holiday and airfare back to yer home as a way of punishing you either!:rolleyes:

Cyclic Hotline

12th Oct 2002, 20:33

Of course the greatest danger of saying never in classifying anything is that you have to consider every potential future event and occurence - not something that many operators or manufacturers (or individuals for that matter) would care to do!

If my memory serves correctly, I believe that the Met lost a Bell 222 following an engine failure.

With respect, perhaps we might discuss that incident from the past - long before any JAR mandated ops were ever in place?

TwinHueyMan

12th Oct 2002, 21:27

Ahh, Twins VS Singles. I've talked on this subject before, but everything always ends up the same - some people say "A second engine is an aid, and I'll take any aid I can get" (my stance), while the others say "Singles have less to go wrong, engine failures aren't that bad, twins cost more, and I'd rather have xxx and xxx than double whiners above".

So, I've got an analogy (gotta love em). Having a second engine is like side-impact airbags. They cost more, yeah, they add more complexity and more to go wrong, yeah, they won't help you if you get hit head on or go under a semi truck, yeah, but they might just save your life if you get t-boned. All accidents aren't t-boning, but some are. They aren't wonder devices, but they just might save me if the situation permits. Kind of like "If we save one life, then everything has been worth it".

Twins can't take over the market, but I'll always prefer two over one going above me. And I'll be ordering side-impact airbags when I land a nice job flying suits around for the big bucks, but until then, my Volvo tank will just have to do :)

Mike

John Eacott

12th Oct 2002, 22:46

"Twins can't take over the market, but I'll always prefer two over one going above me. And I'll be ordering side-impact airbags when I land a nice job flying suits around for the big bucks, but until then, my Volvo tank will just have to do "

THM,

Quite agree, and the overriding factor: Money!! Clients who can be made to appreciate the added safety of a twin will pay for it, those who can't/won't accept the cost of a twin, get what they pay for. My 117 operates, carrying paying passengers, in the sort of conditions that I wouldn't even contemplate putting a single, and would rather walk away from than expose myself and my company to the possible risk of litigation. Fortunately, my clients agree and accept the cost.

Against that, it is a moot point to be operating over built up areas on a regular basis in a single, but the risk isn't seen as such a factor by many, even those professionals amongst us who are posting in this thread. Why? Because everyone does it? Because the clients have been convinced by all the operators offering cut throat rates on 25 year old machines that it is acceptable?

I don't have the answer, and I suspect none of us do. Market forces are driving our industry, from the antiquated offshore support aircraft to the 15,000 hour JetRangers flogging around on general charter. In an ideal world we would get new airframes at least every 10 years, and our choice of single or twin to suit the job and the risk factor. Until then, I'll have to put up with having side impact airbags in my car to drive to work, but providing the client with the machinery that he is willing to pay for, along with every other operator in the business.

GLSNightPilot

12th Oct 2002, 23:22

SASless, we all know that place, it's where we live. But so far, the first day of VFR emergency procedures has been a freebie, to play with. I'll let you know if it's still there in a month or so.

TwinHueyMan, I agree with you, I'll take a twin if I can get it, but I won't hold my breath until singles are made illegal. Money (& short-term money at that) drives everything. As long as the customers take singles at lower prices, singles will be out there, safety be damned. And at least in the US, the guv'mint ain't going to do a thing about it.

Red Wine

13th Oct 2002, 00:37

The other way to think of shutting down your engine, is that it won't get any worse and cause collateral damage when a wheel or bearing lets go....

Heaven forbid.....and you won't see this in any RFM, but you could always start it again for your landing, or if something worse happens to your "Good" engine......so shut it down whilst it is still of some use.
I realise that this idea is not supported in the various RFM's........but hey...its your bum in the seat.
Much the same as running short of fuel and shutting down a perfectly good engine.........better fuel flow / nm traveled [up to the critical headwind component that is]....once again its your bum

:rolleyes: :rolleyes: :rolleyes:

Q max

13th Oct 2002, 17:20

... Since the twin is more dangerous in circumstances where a twin is not necessary and (probably) safer when it could be of use (hovering over the sea for instance) then it all comes down to the :

RATIO of EXPOSURE

.... and clearly becomes mission specific.

exposed time / non exposed will determine the logical choice (in this regard)

TwinHueyMan

13th Oct 2002, 19:04

http://www.aviation.fs.fed.us/safecom/psearchone.asp?ID=3433

I wonder if that guy was happy he was in a twin... :)

Try that in a 205!

Mike

GLSNightPilot

13th Oct 2002, 23:52

Red Wine, I wasn't advocating not shutting down a bad engine. I was saying, probably unclearly, that it isn't unsafe to shut it down, since you still have a good one (you hope!).

Randy_g

14th Oct 2002, 00:09

There's lot's of conjecture about how much safer a twin is. So does anyone have any real numbers to show how much safer a twin is ?? I'm talking true engine failures that aren't related to fuel starvation, accessories, etc. I believe Rotor & Wing did one, and showed a 4% difference.

I wish people would stop trying to compare helicopter flying and driving a car. When everyone gets an a/c then we can compare them. You are far more likely to need a side impact airbag in your car than a second engine in a helicopter. Yes there are operations where twins do better. I won't go very far from shore in a single, and for constant work over a built up area they are preferred. With proper maintenance, and a good daily inspection a single is as safe as atwin, but if you feel safer in a twin then that's okay. I don't have a problem flying a single engined helicopter. I can count on one hand the number of people I know who've had an engine failure. I had a snow ingestion decel, but the auto re-light worked. I also know a similar number who have had serious problems in a twin.

It all ends up as what costs more, and twins do. We would all love to fly twins in all ops, heck what is an emergency in a single, isn't all that urgent in a twin. But is it worth a 50% premium ?? Only you can make that descision, oh and your client.

Cheers

TwinHueyMan

14th Oct 2002, 02:31

Randy,

I was just trying to say that side-impact bags are additional saftey features that don't help in every situation - just like a second engine. The principal is the same, and that's all I was after.

Engines are still the most complex bits in a helicopter. They do fail. While other things do fail, and a helicopter sans engines is still more complicated than just the engine, having a second one can help. It is more expencive, more complex, and (in some cases) more difficult to operate - but when you think of the price of writing off a helicopter due to a heavy auto, botched auto over a city, or a forced landing into the abyss, the extra money looks like pocket change.

There are places where having a twin is an absolute necissity, such as on a CSAR mission behind enemy lines or when the helicopter gets too big for one engine to suffice, but I doubt there is any situation where having another engine couldn't help given one of numerous possibilities. It was realized that there aren't many places to safley set a jumbo jet down save an airport, so why do you think ALL airliners and commuter planes have at least two engines?

I have no problem when people say "twin engines cost more", cause they do, but it bugs me when people say "twin engines aren't safer". The margin isn't that wide, but there is a situation when an engine fails or must be shut down, and the landing options are pretty slim. In that case, having a second engine could be invaluable.

Mike

Randy_g

14th Oct 2002, 03:36

THM I was agreeing with the statement that twins are safer. My point is that singles aren't as dangerous as many like to think. How does one explain the many operators out there who run singles, and haven't had engine failures ?? Lucky ?? Maybe, but I bet they have great maintenance programs, and pilots who pay attention to limitations. Without those it doesn't matter how many engines you've got. With the reliability of modern engines is a twin really necessary. As I mentioned, there are ops when it is preferrable to use twins, but not for all ops. Do you need a 212 to lift an 350 kg (770 lbs) diesel engine ?? A 206, 500, AS350 will do just nicely for half the price (give or take). If you want to be ridiculous, one could ask why all helicopters don't have 3 (like the EH-101) or 4 engines. Just in case you know.

Oh BTW not all airliners have twin engines. The Pilatus PC-12, and Cessna Caravan have only one, and they are used quite frequently in remote areas. Airliners also have dual, sometimes triple systems redundancy. Something most helicopters do not have. Does your 212/412 collective have a redundant hydraulic system ?? What if you have a #2 hyd failure, and a bad batch of fuel, so that both engines flame-out ?? (I know it's far fetched) What would happen to your RRPM ??

My thoughts

Cheers

TwinHueyMan

14th Oct 2002, 06:03

Randy,

I guess we are on the same page then. I agree with you totally - singles aren't as dangerous as many think. However, twins do have a little edge in that one-in-a-million (figurativley) situation. While it's bad for people to forget that there is that advantage with the twins, it's equally bad for people to think that singles are dropping like flies. I apologize if what I said was misinterpreted.

As for that diesel engine, a 212 would indeed be quite overkill. But that's not to say that a 427 or 206LT (if there are any left) couldn't do it and still have that friendly little increase in options if the engine should go south. Say you are floating around about 100m from putting an air conditioner down on a roof when you get an engine chip light - with a twin, you might be able to coast the load down onto the roof in the general vicinity of the insertion point (say right next to the bracket) on 2.5 minute OEI power, rather than either setting the thing down in the mud in the best case or dropping it to it's death in the worst case if you were in a single. Or maybe continuing on the chipping engine while it destroys itself as you gently set the AC down on the roof and prepare to glide down to the parking lot and shut down.

Your comment about the EH's and 4 engined ships brings up a great irony for the pro-twin people. Pro-singles say "a second engine isn't worth the extra money", and I bet pro-twins will say 3 and 4 aren't worth it as well. The chances of an engine failure are out there, but the chances of two or three are down right silly. Plus, loosing 2/3 engines wouldn't be pretty unless you had a HUGE gap between OEI power and MCP AEO power. Going from 1134shp to 1025shp (in the case of my girl) isn't quite as big of a hit as going from 3x to 1x in the case of a double engine failure in a triple. A double failure would put me on the ground ASAP while that EH or 53E might be able to limp along a few miles before it runs out of altitude or 2.5 minute power.

Pilatus PC-12s aren't terribly popular as airliners as far as I know. They are primarily marketed as exec ships, and I don't think they are a smash hit there none the less. The Caravan is a rare specimen that runs along the lines of the Beaver and Otter, but it still has yet to find a place outside of very small scale operations (outside of FEDEX). I doubt the Boeing 787 and 797 will be powered by one mammoth GE90 sibling, nor will the EMB120s and Saabs be replaced by a caravan on steroids. I doubt the MI26's successor will have a single engine either - in the case of that and the airliners, they are too big to be able to auto or glide down into someone's backyard or onto the beach... but that doesn't mean I wouldn't prefer a 427 over 407 just because I can :)

Mike

SASless

14th Oct 2002, 06:14

Randy,

Please flesh out your question....I am flying my trusty Bell 212/412 and my #2 hydraulic system packs its bags and goes home to mother....both engines then fail due to food poisoning.....and you worry I might have main rotor RPM problems? Are you implying...suggesting...stating that the dual engine failure has anything at all to do with the uninterrupted supply of hydraulic power to the collective system? You have me cornfused here laddy.....is my alcohol ravaged memory letting me down here....but from what sticks out from the vapors of last nights gin bottle.....is that both hydraulic pumps on the 212/412 are transmission mounted and as long as the floppy things up above continue to turn....one has "normal" control of both cyclic and collective controls.....depending upon which hydraulic system that fails....then maybe the pedals get kinda cranky but not the collective or cyclic. Now are you per chance confusing the unlikely event that you could simultaneously lose a hydraulic pump and Main Rotor Tacho generator and find yourself with cranky pedals, no rotor rpm showing on the big clock looking thing but with no change in noise or rpm and several lights marked #1 Hyd and a gauge showing zero pressure....and the low rpm audio and other gadgets doing their jobs? The Bell product does sometimes shear the shaft from the transmission to the #1 hydraulic pump with piggyback mounted main rotor Tacho Genny.....very similar concept to the Bell Jetranger....except you only have the one hydraulic system there.....thus revert to no hydraulics and no Main rotor tacho genny. More than one Hero has embarassed himself by ditching a perfectly good Jet Ranger after that has happened.
:rolleyes:

Q max

14th Oct 2002, 18:30

... more noise, buttons, switches, gauges, systems, pilots.

... more importance more PAY! - yup its a money thing!

... more engine sales - more bread extracted from the MOD (lets try and sell THREE engines per helicopter!)

fine enjoy the twin - but just stop pissing on our single bonfire without just cause (15 seconds of takeoff exposure doesn't justify 'banning' singles! )

- extended exposure might (just) justify the twin in some cases sure.

If I were sonar dunking I'd rather be in the machine in which I was less likely to find myself in the water than the machine in which I could have an engine fail and stay dry.

The mil (army particularly) did well with the gazelle - they need more numbers of simply maintainable, reliable, versatile low logistical hassel machines.

There's a squared law of .......etc

nonradio

14th Oct 2002, 19:37

two engines but one pilot and one tail rotor, Hmm....
UKCAA, bless 'em: proposed twin engines thro' single gearbox and prop aeroplanes banned because failure of the single drive system ie prop, would lead to a forced landing. Same logic clearly doesn't apply to flying machines with a big propeller (one) on the top ( not to mention the stern propeller,eh?)
Anyway, 2nd engine is for girls.

PANews

14th Oct 2002, 23:09

This is I know an argument - often visited - with no winners, but do not do down the humble plank wing in the process!

'... Pilatus PC-12s aren't terribly popular as airliners as far as I know. They are primarily marketed as exec ships, and I don't think they are a smash hit there none the less. The Caravan is a rare specimen that runs along the lines of the Beaver and Otter, but it still has yet to find a place outside of very small scale operations (outside of FEDEX) ...'

Both these types are replacing twins in law enforcement in the remotest of places - the wastes of Canada and Australia and undertaking sea patrols off Malaysia and others. In addition operators are pushing quite successfully to get such singles lugging passengers on overwater legs. They will go in - about a year ago a long distance PC12 had an unhappy ending after ignoring a rough engine around Russia someplace, but it is rare enough.

The magic formula for their success is that because where they put the 'rotors' most twin airplanes have dire one engine out performance - but I guess a Chinook with one stopped would be pretty much the same!

It is to toss a crooked coin whether it is better to dunk in a airplane or a helicopter ...... perhaps a rotor would be safer in most instances where you have height but at least it shows that in this 'progressive' world at least there is some reversal of the sinking fortunes of the single at the hands of the deskbound legislators!

Cyclic Hotline

18th Oct 2002, 16:35

To expand a little on the comments on the Caravan, as this is an example of a technological advancement creating a complete re-think of the "traditional" operating and regulatory environment. It was ultimately successful in seeing a complete re-write of commercial operation of single engine operating regulations - a pretty significant achievement I think you would agree.

The Caravan is hardly a rare specimen. It has become the backbone of thin commuter services in remote (and some not so remote) areas, due to its excellent safety record, reliability, economics and operability. It is in use Worldwide and has undoubtedly been proven one of the finest commercial aircraft ever manufactured. Perhaps uniquely (?) it has never had a single FAA Airworthiness Directive issued against it, unlike just about everything else that comes from that factory! ;)

Some facts:

CARAVAN TOTAL FLEET HOURS Over 4 Million
CARAVANS DELIVERED Nearly 1,200
DISPATCH RATE RELIABILITY 99.86%
COUNTRIES OPERATING CARAVANS 66+
1,000th CARAVAN DELIVERED November 1998
REPEAT ORDERS FROM OPERATORS 70%+
HIGHEST TIME AIRCRAFT 20,000+ Hours
HIGHEST TIME AMPHIBIAN 20,000+ Landings
HIGHEST UTILISATION 250+ Hours a month
A/C DEDICATED TO FREIGHT USE 450 +
A/C IN SCHEDULED PASSENGER USE 160 +
SCHEDULED PASSENGERS CARRIED IN 1999 4.1 Million
A/C WITH WIPLINE FLOATS 100 +
A/C IN SPECIAL MISSION OPERATIONS 60 +

For example, the number one regional airline in the world, based in Brazil, currently operates 40 Caravans. In Central America, a large conglomerate of regional airlines started with four Caravans and has just purchased eight more.

There are over 1000 Caravans operating in 66 countries today, and the Cessna Caravans have gained over 50% of the world-wide market share in the utility/small commuter category.

Leading the way in safe, single engine technology - According to the Final report On 135 Single engine IFR Operations in IMC by the U.S. F.A.A The C208 Caravan is the only single-engine airplane that has achieved a substantial and extensively documented operating history providing the information necessary to make detailed safety and reliability assessments. This is primarily the result of a computer-based maintenance program developed by the manufacturer and used by most operators. The experience of this airplane serves as a model for others seeking to expand the operating privileges of their aircraft, and its accident record can provide a first approximation of the level of safety that is attainable with current technology single-engine airplanes operating in IMC."*

This is not to say that this machine is perfect for every application or type of operation, simply that in the choice of equipment an unfettered view will let you understand why your competitor is operating a Caravan and why technological advancement needs to be a continually reappraised.