Carson Blades

[Compressorstall]

Does anyone know what is happening with the SK4 and Carson Blades saga?

[Safeware]

They are still flying trials

sw

[[email protected]]

It was rumoured that there might be a conflict of interest between the Design Authority (Westlands) who must approve the modification and some guys that want to sell us their latest BERP 4 blades instead....oh that'll be Westlands again:{

[Deathbychocolate]

Now I wouldn't normally defend Wastelands, but on this occasion I have to stand up and let people know they are actually doing their bit to make the Carson and five bladed tail rotor work. It can't be easy for them, when they really want to sell their own blades, but they're being grown up and helping.

As for the Carson and new tail rotor, they all appear to be working as advertised, but that's all i'll say!

[strek]

SK4 and Carson Blades saga
There is no saga. What are you fishing for?

[Compressorstall]

Poor choice of words since I normally associate saga with the holidays my Mum goes on and fishing bores me anyway. I was simply interested to see where things were with the SK4 - you can get out of touch stuck at a desk and at my great age all the sqn chums I had have headed off elsewhere - retirement mostly. It just seems we have talked about potential and then it's all gone quiet - I simply thought of it when the media were wheeling out the shortage of SH in Afghanistan the other evening whilst I was drinking my Horlicks. It must be Friday afternoon as I'm being defensive - roll on Happy Hour.

[AdLib]

Now ... SK4 and Gilbert Blades. THAT'S a saga. :}












Sorry, it's been a long week. I'll get my coat.

[Compressorstall]

See you in Happy Hour then...

[forwardassist]

Compressorstall

Give the Junglie Tac Dev bloke at the MWC a ring. He should be up to speed on the "saga".:)

[Cyclic Climb]

He is a Saga unto himself....nice bloke, Scottish i believe:rolleyes:. Also try Bosc' Down (the test blokes) and 846 NAS. The latter being the first Junglie Sqn to receive the blades...the Saga continues....

[Green Flash]

'scuse ignorance - what's the difference between BERP4 and Carson blades, then?

[strek]

One is made by Carson and is fitted and flying on a Sea King with plenty more available at short notice.
The other is designed by Westlands :E

[Green Flash]

Ah, nuff said!:ok:

[Mr-AEO]

British Experimental Rotor Profile 4 blades have very clever profiles that do not just include the tip. The profile alters from about 1/3 chord to the swept tip. Usual aim is to reduce effect of retreating blade stall and choreolis type wake interaction with the following blade. Downside is higher low speed vibration and potential 'cobble stoning'. That's off the top of my head - I'm sure Google will put me straight. BERP4 is planned for the recently acquired Danish Merlin in lieu of the BERP blades currently fitted to Merlin Mk3.

From what I've seen, the Carson blades look much simpler and do not alter the blade camber with chord length; the main difference appears to be the tips.

Would be interested to know a more 'expert' opinion.

[Green Flash]

AEO - thanks.

I'm surprised in this day and age of everything being designed down to the nth degree that you can just stick a new design of blade (a fairly fundamental structure of a helo) onto an existing cab (Merlin) and it will work. I'm not doubting it will work. Presume it's down to developments in computer technology although I'd love to believe someone's being tinkering in a musty old wooden shed for months and produced a revolutionary design!

[Razor61]

According to QinetiQ, the programme to trial the Carson blades on the Seaking Mk4 at Boscombe will finish in November.
20hrs of flight testing is required going by the info, at the time of the info going to press, 4.5hrs were completed. So i gather they should be into the latter stages of the trial now?

See HERE (http://www.qinetiq.com/home/defence/sitrep/rotor_blades_given.html)

[strek]

The link you have added was last years feasibility study that has completed.

[Razor61]

Had a feeling after i posted it actually :(

I'll walk off into the sunset... :\

[Mr-AEO]

Don't forget that the Carson blades are just one part of the upgrade. The 'Indian' Tail Rotor is another part, I would be interested to see if that has gone seamlessley or not:8

[Two_Squirrels]

From what I've seen, the Carson blades look much simpler and do not alter the blade camber with chord length; the main difference appears to be the tips.


The Carson blades have different aerofoils as well as a different tip, and have also more twist. The only thing in common with the older blades is the chord length and radius.

[[email protected]]

Not unlike the BERP blades then - a higher camber section on the outboard end to provide more lift at slower speeds on the retreating side and a cambered section with a reflex trailing edge to compensate for the twisting moments on the outboard section caused by movement of centre of pressure as AoA varies. The tip will deal with the high speed problems on the advancing side - compressibility and critical mach No - probably the same way as the BERP blades too - a thin, swept tip like a supersonic wing.

[Razor61]

Please explain the concept behind the "Indian Tail" rotor...i haven't heard of this before.

a thin, swept tip like a supersonic wing.
Not knowing much about the rotors, is this the bit where it takes form similar to a concorde wing, infact nearly exactly the same form?
I was being explained too about the blades on the Lynx HMA8 by an 815NAS pilot, he went through the various features including the kink in the blade half way down, the tips (i assume are BERPs?) and the supersonic wing like shape right on the tip of each blade.

[3D CAM]

Five bladed tail rotor???
That is what the Sea King started with in 1969! Six blades fitted in the mid 70's. Am I missing something?? :hmm:
(Besides a few vino induced braincells!)

[[email protected]]

Razor - correct, the thin section allows higher speeds before reaching Mcrit and the sweep effectively gives a longer chord and forces any mach waves to propagate at 90 degrees to the leading edge.
The kink in the trailing edge of the BERP blade is where the 2 different aerofoil sections meet and ckearly shows the reflex trailing edge of the inboard section.
3D - I don't comprehend the wisdom of returning to a 5 bladed TR either unless they have improved its lifting capability by cambering the aerofoils.

[steve_oc]

As far as I recall the "Indian" tail rotor was 5 blades but better design including cambered blades giving more thrust (long time ago now). The Carson blades add roughly 10 kt and 1500 lbs lift capability on an S61 for the same power.
Quote from a colleague who did an evaluation flight test of the Carson blades in Canada: "Send money now".

[Mr-AEO]

That's all very well, but what happens when all the cabs have shaken themselves to pieces in 4 years?:} That will put a fly in the ointment of Sea King 4 life extension to 2017.

[HEDP]

Sorry Chaps,

The BERP being no longer 'experimental', I thought the correct term for the Westlands blade was the Advanced Surface and Planform (ASP) blade, or am I mistaken?

Secondly, I believed increases in max speed in the order of 140kts for SK had been mentioned on these forums with the new blade. This would seem to be in conflict with a mere 10kt increases also mentioned by Steve. Without compomising opsec, is there an increase quantified as if the IRT is to be taken on by SK then speed of response may well be compromised by a somewhat slower cruise speed than the venerable Chinook?

Always willing to be educated,

HEDP

[BossEyed]

... the Westlands blade ...

Westlands build the thing, having resolved some tricky production engineering issues to do so, and so can be considered the mother of BERP. But the father was RAE, who did the tricky aerodynamic design.

ASP was a term bandied about in the past, but WHL press releases nowadays refer to BERP IV (http://www.agustawestland.com/communication_det.asp?id_news=309&yy=2007).

[[email protected]]

I heard a rumour that Carson are buying S61's and Sea Kings to give them the full Carson modification - MR, TR and lifting frames with the promise of 160kt cruise, 25,000lbs AUM and no cracking.

Then they will probably sell them to the MoD who still won't have done anything about addressing the shortfall in heli lift capability and who will then have to pay twice as much for them as they would if they just got Carson in to modify our existing fleet.

If they could just stop them leaking when it rains............:)

[Mr-AEO]

Stop Sea Kings leaking???:ooh:

You must be off your noddle matey:}

We all know that the best place to put the gobbby booty is underneath the drip tray after a heavy rainfall. Gloop! And he's covered with OM15 and water mix after the first banked turn!:ok:

Anyways - MOD has done something about adressing the lift shortfall - the Danish Merlin and also Chinook Mk3 reversion....

[John Eacott]

I heard a rumour that Carson are buying S61's and Sea Kings to give them the full Carson modification - MR, TR and lifting frames with the promise of 160kt cruise, 25,000lbs AUM and no cracking.


No cracking? 160kt? Mate, the current Carson S61's just about run out of forward cyclic at 130kias :p

The blade performance is truly remarkable, but your mooted higher cruise speed is a recipe for disaster unless some serious re-rigging of the flight controls is achieved. As for the stress on the airframe, I'm not at all sure the old girl would take much in the way of significantly higher cruise speed?

[[email protected]]

John - this is a rumour network and I heard the rumour but couldn't validate its veracity. 160kts does sound a bit unlikely though:)

[22/7 Master]

Trials in US going well. Performance is in excess of expectation. I wouldn't bank on the Sea King getting BERP IV now as I don't think the Sea king can take a paddle tip, only a swept tip so BERP IV performance increase over Carson will be marginal at best.

Serves wastelands right for not pulling finger out and developing sooner.

Bring on the life extention programme.

[[email protected]]

The irony is that MoD were offered BERP blades for the SK when they were first being developed and some genius decided that it would be better (cheaper) to go for plastic blades exactly the same shape as the metal ones.

[Sven Sixtoo]

You sure on that, crab?

I thought the SK was a sort of production-level test of the technology for making composite blades in industrial quantities. Once Westlands had cracked the production process they then went on to exploit it to produce complex shapes (for other types).

I could be wrong of course, and it is a memory from a long time back.

Sven

[MaroonMan4]

Sorry guys, this is all semantics to me - why on earth are we trying to patch up an aircraft that is long past its sell by date. All of this money and effort for what real benefit.

She has been a superb aircraft (and still is in certain roles) but as an SH in a JPR or lift role - sorry I think that we are chasing rainbows when you look at the threat, temperatures and height together.

I fail to realise why we dont just cut our losses and sort out the shortage of lift problem once and for all. Whether we like it or not the Freaks are doing a pretty good job and satisfies the medium side of the market, the twin bladed torque monster is doing admirably with the larger end - and soon, f we really do need a small battlefield taxi to ferry Melchett and Darling around we will have Future Lynx (or whatever it is called today!).

My point being - we have already brought some more Merlins, lets buy some more CH 47 - give them to the Junglies and let the Junglie boys crack on with what they are good at, but with proper aircraft - not trying to bluff politicians, press, military top brass not in the know and in some cases the aircrew that carson blades makes the NAO report all go away and help the commanders/guys on the ground.

And what makes it worst, that heaven forbid if something happens for whatever reason there is absolutely no way that the future BoI will record that the aincident/accident was actually caused by inadequate funding or low resources - nope it will mention the authorisation or supervision or mis handling hot n high or whatever - but it will not say ' hey fellas, dont worry we knew that we were expecting alot from you but we didn't have anything else so sorry someone/something had to go!

Now if I am wrong and the Junglie bunch think that the Carson blades are the silver bullet then I will 'suck back' (you see I am Joint - I know some fishead lingo!) - but with Boeing/Westlands already in bed with Apache, current CH 47, Presedential 101 then surely under a US Foreign Military Sales agreement some CH 47s can come from somewhere (as the 101s came from the Danes?)

[RumourMonger]

Surley patching the RAF`s Pumas and the Fleet Air Arms Seaking 4 is just going to create a bottle kneck further down the line as will they not need replacing round about the same time as the Bulk of the RAF`s Chinook Fleet. This is probally thread creep but to me we seem to have two problems to contend with an immediate shortage of capabiltiy, and a need to replace those types with new to maintain and maximise future roatry wing capability in the future. Rather than sending you guys to war in the equivalent of a Ford Cortina (Sorry for you youngsters who might only have vague recollections of your Dads pride and joy-If I recal the Seaking Mk 4 entered service the same time as Fords produced their Mk 4 Cortinas - now how many Cortinas do you see on the road today). OK here`s an idea The Forward Active Fleet for the RAF Chinook Fleet acording to the DASA is 25 the total Chinook Fleet is 40 that leaves fifteen airframes in Reserve and if I recall the Merlin Forward Active Fleet is 15 again According to DASA which leaves Seven. So why can these not be brought into use to satisfy the immediate need and acquire new airframes as attrition replacements. Or is it a case that those aircraft from the reserve fleet have been canablised that much that they will not be flying in a month of Sundays? The UK already owns these aircraft, would not have to go shopping for new and they are of a type already deployed into Afghanistan and Iraq

[Not_a_boffin]

MM4

One minor problem. The Junglies are supposed to go to sea - not all the time and obviously not exclusively, but they must be able to do so for extended periods. Without folding heads that just isn't a practical proposition for the Wokka despite the sterling efforts put in by the Odiham lads (and the Air and AE departments of Ocean & Ark). Just ask them about the problems they have with blade sailing and relative wod.
Ditto Merlin 3 & 3A although with less of the blade-sail issues.

If we were to buy a Junglie Merlin, then the IT navy amphib version would probably be it, although at less payload than the 3/3A for obvious reasons. If we don't, then Mr Sikorsky has an option at the heavier end of the market, but that's a new fleet.

There is NO easy way forward for what was FASH before it became SABR and FRC. But a way forward has to be found - as you say patching up the SK4 is just storing up trouble for the future.

[WE Branch Fanatic]

Not_a_boffin

Jane's Fighting Ships listed the Merlin HC3 as a "shipborne aircraft". Has it ever been to sea?

It also mentions a marinised Chinook study.

MM4 isn't there a case for JHC having several diferent sized aircraft?

Also will the Sea King ASaC 7 get the new blades? Could the new blade enhance the performance of the Merlin as a potential MASC platform (as discussed on the Future Carrier (http://www.pprune.org/forums/showthread.php?t=221116) thread)?

I would like to say sorry for asking this very daft question, since I know Merlin blades are very different from Sea King ones. Unless of course Sea King ASaC 7 + new blades = MASC:eek:

[Tourist]

WEBF.

"Could the new blade enhance the performance of the Merlin as a potential MASC platform (as discussed on the Future Carrier thread)? "

Since the new rules pertinent to the discussion of military matters on the web prohibit me from explaining just how stupid a question that is, I will have to satisfy myself with this.

:rolleyes:

[Not_a_boffin]

WEBF mate, never, I say again never, take what is in Jane's as fact! For years they perpetrated a myth that USS Independence (I think it was) had had her port lift moved aft as part of a SLEP.

I don't think 28 have ever been to sea with HC3 and certainly would struggle given non-folding head, non-folding tail and all sorts of other weight-saving measures.....never mind the airframe, which is dissolving away even on the HM1!

[[email protected]]

Boffin - surely not......something made by Westlands not doing what it was procured for (rotting airframes in a shipborne helicopter):ugh:

[Evalu8ter]

Unfortunately despite having CH47s & Merlins in the "reserve fleet" you can't just give them to the front line, as the reserve fleet contains all the ac undergoing essential Major servicing, accident/battle damage repair and modification programmes. Hence, they are mostly in bits...
We can't just buy CH47s off the shelf..I think we would have done if we could source any. This is probably the rationale behind the Merlin Mk3A and the Chinook Mk3-to-SH decisions.
Taking Mk3 Merlin to sea is pointless; same deck space as a CH47, doesn't fold and half the payload. Folding Italian Merlin, with uprated engines and transmissions would be a player. Boeing are unlikely to support a marinised CH47 (unless you pay them a LOT of money)- the market is too small as the USMC have chosen a MV-22/CH-53F mix.
WEBF, yes JHC should have different size aircraft for different roles. The SK4/Puma replacement will possibly be the same airframe to fulfill the medium-sized helo roles; the FLynx is the small Colonel's taxi - the only (slightly hackneyed) snag is the CH47/Merlin issue.
But as NaB points out, the CH47 is far from optimised for the LitM role. But, in calm waters and as part of a TAG, it will always be there as it does things that other JHC assets simply can't.

[dangermouse]

The Mk3 had always had a capability to operate off ships if required (it is in the basic specification of the aircraft), this should not be interpreted as being a naval aircraft, it's in the same kind of capability as Ch47 on a ship (ie on CVS, LHD etc not FF or DD)

No SHOL trial for a Mk3 has been carried out yet but there won't be any problems as the basic airframe should be OK as all EH101s are structurally and materially virtually the same. Deck handling has proven OK with the MMI aircraft (same U/C configuration).

The aircraft talked about is already flying, check out the DMRH and JSDAF variants, RTM322 powered folding aircraft. BTW the danes kept their folding ones, the Mk3As will not have folding heads (commonality with Mk3?)

DM

[Not_a_boffin]

DM

No argument that Mk3/3A will be able to launch and recover from a ship - clearly it must or you can't even do SHOLs. As ever, the problem is what you do with them if they're not airborne on an operational ship. No head or tail fold on an a/c with a 19m rotor diameter and 23m length = no useful maritime capability - hence the comments re the MMI variant.

[dangermouse]

what the civil basis of certification for the Carson MRB is?

ie is it certified to FAR/FAR 29 (allowing passenger carriage) or what?

DM

[dangermouse]

I have tried without success to find the civil cert records for the MRB, I do find it strange that the Carson site doesnt quote which FARs the blade has been certified against.

I have heard a rumour (appropriate for this site) that the blade has not been cleared by the FAA for passenger carrying aircraft i.e its use is limited to cargo/logging operations which begs the question how can we carry troops using them?

DM

[Two_Squirrels]

I have heard a rumour (appropriate for this site) that the blade has not been cleared by the FAA for passenger carrying aircraft i.e its use is limited to cargo/logging operations which begs the question how can we carry troops using them?



Maybe because the FAA do not regulate, certify or qualify, in any way, British military helicopters?

[dangermouse]

of course the FAA don't certify UK aircraft, that is the platform IPTs job

but if the blade has not been designed to do the job we are asking of it (ie carry people) should we really be expecting it to achieve compliance with UK rules? therefore what degree of non compliance will our aircrews be required to accept and what additional risk does that introduce? (there is no slight on Carson meant here, they have a blade designed against a set of rules, I am just trying to find out what rules)

This also suggests that any future procurement would not HAVE to be Def Stan compliant thus the precedent will have been set as to the level of compliance actually needed, which should allow for a faster and cheaper procurement chain. I guess the team at BD won't be happy, they can't now expect to use one set of rules for a QinetiQ led procurement and yet hold everybody else to a higher standard (the end user should be better served in the long run though).

before anybody rips my head off I have no evidence either way regarding FAR29 compliance, as my earlier posts say, if anyone can point me towards exactly what the blade is certified to I would appreciate it.

thanks in advance DM

[Tourist]

dangermouse, you're right!
What if the blades found out they were carrying troops and not logs!?
They might stop spinning out of sheer pique!

[212man]

Well, I know for a fact that Cougar Helicopters (in Canada) use it for public transport, so I assume it's been certificated to an appropriate standard.

[dangermouse]

that clarifies it, they must be FAR29 compliant (or its equivalent)

Tourist you missed the point entirely, the design standards for passenger carrying aircraft and components ARE different to non-pax carrying aircraft so the blade does care. Pax carrying rules (ie FAR29 etc) are very rigorous regarding structural strength, damage tolerance and fatigue life calculation, logging etc has a completely different usage spectrum and flight envelope to pax carrying flights and that is why the rules are different.

read them before making silly comments like that

DM

[forwardassist]

Crumbs, DM! Sense of humour out for repair? :p
But why do you need to know? Are you a Wastelands spy ready to poo-poo any success the Carson blades may have or just an interested outsider? However, I suppose that if you needed to know, you would already know, you know? :}
Oh, it's too early.........

[Tourist]

No dangermouse, I think you missed the point.
If the blade is safe enough for me as a military pilot flying a military registered a/c, then it is safe enough for my cargo, be that a load of potatoes or passengers

[dangermouse]

however I do know people at WHL (who really resent the term Wastelands, all the guys I know always have the best interests of the boys and girls flying the stuff in mind) and am sure that if a WHL designed SK blade had been chosen it would probably beat the Carson design and be fully Def Stan compliant as well, but the UK MoD didnt appear to want that and went for a quick off the shelf solution. I understand the timescales involved but replacing a major component like a blade that the airframe designer has no knowledge of (and isnt leading the testing of) seems a little risky to me, especially if the standards that are now being accepted for service are not those imposed on the original component.

I was interested to know what the blade was certified against as it starts an interesting line of thought regarding compliances for military front line operations, as my previous thread tried to say (poorly I guess), it opens the door for a quicker acquisition route for equipment as full Def Stan compliance no longer appers to be compulsory, which can only help UK industry and the end user.

Actually the fact that a piece of equipment has been determined to be 'safe enough' for one role doesnt read across to others. The IPTs accept levels of risk that change dependant on the mission involved. A cargo carrying sortie may well have more acceptable risk than a passenger carrying one due to the lower potential loss of life in case the worst happens. The civil world is different, there are levels that are just unacceptable regardless of the 'mission', the Military dont work that way.

DM

[forwardassist]

JunglyAEO
Well said. :ok:
The only other point I was going to mention is that this capability was/is needed in a short space of time, and no amount of claims by Wastelands about how good their blade will be compared to a Carson blade would help their case, since it is a "paper" blade, with zero hours airborne time.
Time was, and still is, the pressing factor.

[dangermouse]

I even acknowledged the timescale constraints, it just seemed to me (and thats why I asked the original question) were we cutting TOO many corners to expedite this acquisition, it would appear not and that is reassuring. It is equally important to recognise however that a quick UOR solution MAY come back and bite later on (Carson MRB effects on the airframe components probably havent been quantified yet)

Again whilst it is fair to say that anybody can bid for work, if a bid process is not used it's kind of difficult to enter the race. I stand to be corrected but wasnt the Carson acquisition a non bidded contract? (again for understandable timescale reasons). Maybe if WHL had bid for a SK re-blade the playing field may not have been level. Would a WHL proposal for a non Def Stan compliant blade been acceptable?, I guess we will never know.

I understand that the Carson blade purchase is a small number for part of the Mk4 fleet only so it might only be an interim acquisition whilst the real 'production' items are sourced which would give Industry in general the chance to bid for the long term solution

I hope that the RM aren't let down in all this

DM

[MaroonMan4]

Jungly AEO,
Oh deary me - so from all accounts you must be one of those earmarked to go and dont want to miss out on the chance of another gong on the chest. All this stuff about 'primitives surviving' and 'truisms of war' and 'going with what you have got' either smack of a swallowed staff college publication or a script from Blackadder.

The sad thing is that I really do hope that your optimism is right and that this post is pure drama queens making a mountain out of mole hill.
My thrust and passion (and very nearly a WEBF obsession) is that if we are as broke as not to equip our aircrew with the best, most technologically advanced, fighting, armed, defended, agile, manoeuvreable aircraft that the Her Majesty can get her hands on, then lets not spend the money on a half hearted attempt.

If at the end of the month I am that broke I dont go shopping - and if I really do need something at the end of the month, when the bank account is empty, I apply for a loan to ensure what I really need is properly done - or I go without.

When people's lives are at stake, this is a situation that requires the Treasury and the bean counters to put their hands in their pockets and stump up. There are CH47s out there and a US Foreign Military Sales will rapidly acquire them for us (that special relationship is not dead).
As to HMS OCEAN, folding heads, lifts - sorry - not convinced. The current 'war' for UK whether we like it or not is Afghanistan and Iraq, both do not need an Amphibious presence.

If those in positions of power were to take any risk it must surely be with the Amphib boys - if it is that strapped that it is piling everything into a committment without a ship in sight, then who cares about folding heads, lifts etc - lets win todays battle and let the procurement boys sort out the right aircraft with all of the bells and whistles when we have extricated ourselves from this 'War On Terror'.

Ironically, the Sea King (by its very name) is ideal at plugging the Amphib role where training must be continued for the wars of tomorrow. But in the interim (for this war - here and now - with troops in contact as we type), if both Canada and Australia are sourcing extra CH47s (and lets be honest this is what is really required in Theatre) then lets wake up, smell the coffee and give the Junglies 6 CH 47 to do the job properly.

I will get off my soap box, and I really do hope that the blades and mods provide what is required and all return home safely - there is no doubt that I will not mind one bit in being proven wrong on this one and if humble pie is required in the years ahead then I will eat it with a smile.

Now, if the CH47 is is too big and it is not lift that the boys on the ground want, but a smaller capability - then give the Junglies the 6 Dane Merlins. Not quite an HH-60 but better than a Sea King, even on steroids!

Fly safe

[Two_Squirrels]

DangerMouse,

I was interested to know what the blade was certified against as it starts an interesting line of thought regarding compliances for military front line operations, as my previous thread tried to say (poorly I guess), it opens the door for a quicker acquisition route for equipment as full Def Stan compliance no longer appers to be compulsory, which can only help UK industry and the end user.

My point is that Def Stan and FAR29 are very different beasts. FAR plays no part whatsoever in Def Stan 'certification'. There are probably no aircraft in the entire inventory that are fully in 'compliance' with Def Stan anyway. The collected skills of the RTSA, IPT, QinetiQ, and Agusta Westland (yes, they ARE involved), will 'certify' the blades in an appropriate and rigorous way that will ensure that the blades are safe for use.

[Razor61]

http://www.mod.uk/DefenceInternet/DefenceNews/EquipmentAndLogistics/NewBladesImproveSeaKingPerformance.htm

The Seaking HC4's out in Afghanistan have had the CARSON blades fitted as an UOR along with the new tail rotor.