Hello "Oscar Charlie"

[sheepshagger]

having worked in the offshore industry most of my life I have had great faith in the S61 helicopters over the years they are comfortable roomy if a little noisy, but above all they were reliable.

While in Denmark last month where they operate 4 S92s for the rigs all of them were out of service due to various mechanical faults, while this caused a delay to me getting home and the misfortune of having to fly on a super puma (cramped, uncomfortable and very noisy) not too much of a problem.

But with so many mechanical problems I have to wonder at the wisdom of using these S92s in a search and rescue roll, where lives are at stake I would be much happier knowing a 61 was sitting on the ramp ready to go than a 92 that may or may not be ready to go.

Maybe it would be a good idea to keep one of the 61s on standby for a while, just until all the teathing problems with the 92s have been sorted out.

 

This is not a dig at the crews who do an outstanding job but the beurocrats who only give a turd about money

[Njugle]

The Good

http://www.sikorsky.com/details/0,,CLI1_DIV69_ETI1548,00.html

 

The Bad

http://www.ainonline.com/ain-and-ainalerts/aviation-international-news/single-publication-story/browse/0/article/s-92-operator-addressing-a-vibration-issue/?no_cache=1&tx_ttnews%5Bmode%5D=1&tx_ttnews%5Bstory_pointer%5D=8

 

& The Ugly.......

http://www.pprune.org/forums/showthread.php?t=163206

 

.....prospect of trawling through 44 pages of discussion on the subject.

[Sudden Stop]

Ah well, you see it is already happening...

 

The coastguard 92 in Stornoway reportedly returned to base today suffering an emergency of it's own. I assume it was only out training to start with but could easily have been a real shout.

 

Helicopters are most likely to break down when they are either brand new or at the end of their life span. What would you prefer an old unserviceable aircraft or a new shiny one? I know the old oscar charlie was the 'devil you know' and had a good record but that couldn't continue forever.

 

It's anyone's guess how these machines are going to work out, but the alternatives are few and far between.

[sheepshagger]

The denmark incedent wasn't the first time I've been delayed due to problems with the 92 just the first time that all the 92s were out of service at the same time.

since writing the post earlier I started disscussing this with a few of the lads out here and every one of us has had at least 2 delays due to mechanical problems with the 92 (some of the guys that work in Norway a lot have had a hell of a lot more) not a very good record for a chopper that has only been in service for a couple of years, only once in 20 years have I been delayed due to mechanical problems with the 61.

and the super pumas dont get me started about that bloody sardine tins I hate them with a passion.

After all that though when they (the 92s) work they are comfortable and a pleasure to fly in (on the way home at least).

[penfold]

Every aircraft has such problems when first introduced into commercial service to a varying degree, you stated that in over the 20 years since you started flying in helicopters to get you to the rigs you were only delayed by a technical fault on the s61 once, fact is they had been in service in the north sea/offshore industry for at least 15 years prior to you starting offshore sheepshagger so most of the teething problems and faults had been ironed out by then, usually by changes in maintenance schedules or improved parts and design practices.

 

Suddenstop I read that on pprune about the Stornoway S92 something about turning back after a engine fire warning light coming on, I seem to remember that there was a Coastguard S61 lost to an engine fire a while back down at one of the southern bases?

[sheepshagger]

My point being that the teething troubles should be ironed out before it is put into service as a rescue helicopter.

A delay in me getting ofshore is great a days pay for sitting in the pub and a night in the hotel, a delay getting me ashore is a pain in the ass, a delay in the chopper coming to the aid of a sinking boat, burning rig, someone trapped by the tide does not bare thinking about.

[Njugle]

^ as featured on the BBC TV docu-thingy about the southern Coastguard services, and if i recall correctly the pilot stated he'd had 7(?) engine failures due to fire or otherwise in the course of his career, poor chap.

[Trønder]

Why hasn't the British coast guard procured the Merlin?

[penfold]

Good god Tronder havn't you noticed we never buy British

[penfold]

I agree with your sentiment sheepshagger but unfortunately the fact is that Im not sure what the options would be for a "shinny new Helicopter" for SAR would be? one that is tried and tested and has been in service in commercial conditions for the length of time needed to have the niggly things ironed out?

 

MKII Super Puma? EC 225? Merlin/EH101?

 

The coastguard were not going to allow the S61 to fly ad infinitum for whatever reason, and they are not willing to pay for a shadow crew to sit at every Marine Coastguard Agency SAR base with a S61 just in case the new toy breaks down when it gets stuck outside to go flying for the next 5 years?

 

We all would like a service that covers every eventuality but when it comes to paying for it then people start looking for a cheaper way a "more cost effective solution" I think the number crunchers call it

[sheepshagger]

please god not the super puma I might find myself willing to go down with my ship rather than get on one of them

[Guest Anonymous]

Ah well, you see it is already happening...

 

....... I know the old oscar charlie was the 'devil you know' and had a good record but that couldn't continue forever.

 

Maybe not, but "Oscar Charlie S61" has no doubt been rebuilt many times in her career. Not just replacement engines, gearbox, etc,. But many parts of the airframe would have been replaced as well. And given the stringent controls placed on aircraft of this type, there is no doubt that OC could have continued in the role for many years to come, and no doubt she will continue to fly for many more years doing good work elsewhere.

But, and sadly it is a big BUT, technology advances. The S92 has a greater range and speed than the S61. It has better technology on board. And should be the aircraft which will see the service through the next 20 - 30 years.

That's the aviation, and commercial point of view.

NOW!

To put a Shetland point of view on this change.

Everybody complained when the very reliable HS748 (Budgie) was replaced by the ATP... And well,,,,,

Everybody was right....

[penfold]

Ahh the BAE ATP aka as the "scud" because you never knew where it was going to land, I used to watch them taking off on warm days and struggle to get into the sky, by the time you had reached cruising height it was time to descend again!, In seriousness though Auld rasmie every aircraft has its problems and good points but you tend to find the longer they have been in service the less "niggly" things there are as the engineering staff have had experiance of dealing with them and have had to solve most technical breakdowns at one time or another,

 

Sheepshagger yep compared to the S61 the super Puma is cramped inside, but its one of those anomalies the S61 has the room to take 18/19 bears and their baggage but doesn't normally have the legs to carry them any distance, and the Puma has the legs to carry the 18/19 bears and their baggage but nowhere to put it all!

[Para Handy]

ATP or Another technical problem?

[Infiltrator]

Did someone mention the ATP?

 

Regarding ATP reliability, the following should just about cover it.

Undaunted by technical realities, the design team at British Aerospace has announced plans for the ATP-XL, promising more noise, reduced payload, a lower cruise speed, and increased pilot workload.

We spoke to Fred, a former British Rail boilermaker, and now Chief Project Engineer. Fred was responsible for developing many original and creative design flaws in the service of his former employer,

and will be incorporating these in the new ATP-XL technology under a licensing agreement. Fred reassured ATP pilots, however, that all fundamental design flaws of the original model had been retained. Further good news is that the XL version is available as a retrofit.

Among the new measures is that of locking the ailerons in the central position, following airborne and simulator tests which showed that whilst pilots of average strength were able to achieve up to 30 degrees of control wheel deflection, this produced no appreciable variation in the net flight path of the aircraft. Thus the removal of costly and unnecessary linkages has been possible, and the rudder has been nominated as the primary directional control.

In keeping with this new philosophy, but to retain commonality for crews transitioning to the XL, additional resistance to foot pressure has been built in to the rudder bias system to prevent over-controlling in gusty conditions (defined as those in which wind velocity exceeds 3 knots).

An outstanding feature of ATP technology has always been the adaptation of the PW100 engine, which mounted in any other aircraft in the free world is known for its low vibration levels. The ATP adaptations cause it to shake and batter the airframe, gradually crystallising the main spar, lock the port maingear after retraction, desynchronise the accompanying engine, and simulate the sound of fifty skeletons fornicating in an aluminium dustbin. BAe will not disclose the technology they applied in preserving this effect in the XL but Fred assures us it will be perpetrated in later models and sees it as a strong selling point. "After all, the Concorde makes a lot of noise" he said, "and look how fast that goes."

However design documents clandestinely recovered from the BAe shredder have solved a question that has puzzled aerodynamicists and pilots for many years... how does the ATP actually fly ?? These documents disclose that it is actually noise which causes the ATP to fly - the vibration set up by the engines, and amplified by the airframe, in turn causes the air molecules above the wing to oscillate at atomic frequency, reducing their density and creating lift. This can be demonstrated by sudden closure of the throttles, which causes the aircraft to fall from the sky. As a result, lift is proportional to noise, rather than speed.

Fred was at pains to point out that during the take-off phase, the previous equation is not applicable as the net take-off flight path is completely proportional to the willpower of the flightdeck, cabin crew and passengers combined. "Any single person not willing the aircraft to become airborne could cause a major accident," he commented.

In the driver's cab (as Fred describes it) ergonomic measures will ensure that long-term ATP pilots' deafness does not cause in-flight dozing. Orthopaedic surgeons have designed a cockpit layout and seat to maximise backache, en-route insomnia, chronic irritability and terminal (post-flight) lethargy. Redesigned "bullworker" elastic aileron cables, now disconnected from the control surfaces, increase pilot workload and fitness. Special noise retention cabin lining is an innovation on the XL, and it is hoped in later models to develop cabin noise to a level which will enable pilots to relate ear-pain directly to engine power, eliminating the need for engine instruments altogether.

We were offered an opportunity to fly the XL at British Aerospace's development facility, adjacent to the BritRail tearooms at Little Chortling. (The flight was originally to have been conducted at the Prestwick plant but aircraft of BAe design are now prohibited from operating in Scottish airspace during avalanche season). For our mission profile, the XL was loaded with Benbecula passengers for a standard 100 nm trip with BritRail reserves, carrying three pilots (all Captains, due to crew shortages) and 68+40 passengers (all from the same family) to maximise discomfort.

Passenger loading is unchanged, the normal 'prop rotating in wind of 5 knots, due to slack groundstaff failing to secure it' syndrome, inflicting serious lacerations on 71% of boarding passengers, and there was the usual confusion in selecting a seat appropriate to the nearest emergency exit. The facility for the clothing of embarking passengers to remove oil slicks from engine cowls during loading has been thoughtfully retained.

Start-up is standard, and taxiing, as in the standard ATP is accomplished by brute force. Takeoff calculations called for a 250-decibel power setting, and the rotation force for the (neutral) C of G was calculated at 180 ft/lbs. of backpressure.

Initial warning of an engine failure during takeoff is provided by a reduction in vibration of the flight instrument panel. Complete seizure of one engine is indicated by the momentary illusion that the engines have suddenly and inexplicably become synchronised. Otherwise, identification of the failed engine is achieved by comparing the vibration levels of the windows on either side of the cabin. (Relative passenger pallor has been found to be an unreliable guide on many ATP routes because of ethnic consideration).

Shortly after takeoff the XL's chief test pilot, Capt. Bloggs, demonstrated the extent to whch modern aeronautical design has left the ATP untouched; he simulated pilot incapacitation by slumping forward onto the control column, simultaneously applying full right rudder and bleeding from the ears.

Whilst initially noting nothing out of the ordinary, on discovery that Capt. Bloggs actually was incapacitated, the crew of the XL discovered that, like its predecessor, it demonstrated total control rigidity and continued undisturbed. Power was then reduced to 249 decibels for cruise, and we carried out some comparisons of actual flight performance with graph predictions. At 5000 ft and ISA, we achieved a vibration amplitude of 500 CPS and 240 decibels, for a fuel flow of 700kgs/hr making the ATP-XL the most efficient converter of fuel to noise after the Titan rocket.

Exploring the Constant noise/Variable noise concepts, we found that in a VNE dive, vibration reached its design maximum at 1000 CPS, at which point the limiting factor is the emulsification of human tissue. The catatonic condition of long-term ATP pilots is attributed to this syndrome, which commences in the cerebral cortex and spreads outwards. We asked Capt. Bloggs what he considered the outstanding features of the XL. He cupped his hand behind his ear and shouted "Whazzat?"

We returned to British Aerospace, convinced that the XL model retains the marque's most memorable features, whilst showing some significant and worthwhile regressions.

BAe are not, however, resting on their laurels. Plans are already advanced for the HS748-XL and noise tunnel testing has commenced. The basis of preliminary design and performance specifications is that lift increases as the square of the noise, and as the principle of acoustic lift is further developed, a later five-engined vertical take-off model is also a possibility.