HMS Queen Elizabeth. 3 years, no jets then scrapped.

I see Meerkatz is an expert about Maritime airpower too. Where does he find the time? I wish I'd done all the training and got the operational experience he obviously has.
Meerkatz VC and bar, DCM, DSO and triple bar, MM, MC and bar, DFC and four bars, DSC and eleventy twelve bars. One CMOH.

19 silver stars one brown star, receiving.

6 weeks in colly for a failed power point presentation, upped to 12 weeks due to the piss poor tea and coffee served.

Dishonourable discharge for overstating any military service or awards for gallantry.
 

wafubustard

War Hero
I think a major cause of Merlin being u/s is the lack of spares.
I have been involved with cannibalizing a rotor head which had less than 40 hours in it.
The only way we could get spares was by using the D state routine. Then we would get the item from Westland.

I always thought the spares were sat on the shelf ready for use but not signed as serviceable until we needed it. Once the D state demand had been used Westland could charge more for the spares.
 
PhotEx argues the design is wrong and as such serviceability is low. I suspect lack of ILS support may be an issue. He also suggests if it was not crap we would have ordered more of them....

As NaB concurs, there is an inherent design issue with the gearbox. It’s operating limit is its maximum design limit - it’s like driving your car around flat out in 4th rather than 5th. Same speed, but it flogs the crap out of the helicopter . - quelle surprise, they break down a lot.
We won’t buy any more, not never, coz the gearbox is still crap, and no one at MOD going to invest umpteen million In designing a new one, then invest the cost of fitting more powerful engines and rotors for a one off buy on a helicopter that’s a market flop - no one serious is buying it - and it’s replacement is already being eyed up by MOD.

We are where we are, bought the wrong helicopter, it cost so much, we couldn’t justify the cost and cut the order, and now we ain’t got enough.

The Navy will soldier on with not enough helicopters for a decade until it can buy whatever the Americans decide is their Future Vertical lift programme SH-60 replacement, and buy that.
In the meantime, a buy of MV-22’s will help by freeing up Merlins from non ASW/AEW things they don’t need to be doing.
And counteracting out VETREP on the RFA’s to someone like Bristows as per US Navy practice would help too.
 

Yokel

LE
Reliability of deployed aircraft might be considered the number of sorties completed divided by the number of sorties planned.

R = Ns/Np

Ns = number of sorties achieved.
Np = number of sorties planned.

Do any open source statistics exist for Merlin HM2?

Availability is the proportion of the fleet that can be deployed on any given day:

A = Ad/At

Ad = number of deployable aircraft
At = number of aircraft in total

It follows that a very reliable aircraft (or other system) can have good reliability, due to good design, manufacturing, maintenance, and flying, but low availability due to constraints in terms of spares. I think this is what the FE@R concept is all about.

Conversely an aircraft could have good availability (lots of spares and so on) but low reliability as significant numbers of sorties need to be abandoned or cancelled as the aircraft is stuck on deck or develops fault whilst flying.

I am thinking of the eight RH-53s that took of from USS Nimitz for Operation Eagle Claw. All eight launched - so that was 100% availability. One turned back, another had a fault warning and landed, and a third developed a fault. Hence a reliability of 62.5%. Of course five aircraft was not considered enough to continue the mission, and then there was a tragic accident with a Hercules tanker.

Since the number of aircraft that can be deployed in a single unit will be relatively low (I am thinking of the single aircraft aboard a frigate or RFA, or nine aboard a carrier (in future) it makes sense to make the aircraft as reliable as possible. Redundant systems,belt and braces design, everything checked and double checked, aircrew and maintainers trained as well as possible so that on the day they can deliver. However, this probably means lower availability as spares mean cash.

@jrwlynch over to you!

PS Surely weight limitations due to the gearbox are more of an issue for load carriers? A troop carrier at altitude has greater problems than a Pinger at or near sea level.

PPS When Merlin was ordered, was there any other ASW helicopter with the same endurance on the market?

PPPS Would a Bristows (I thought they got bought out?) cab aboard an RFA be able to legally carry out an ASW, ASuW, ISTAR, or amphibious assault sortie?
 
I think a major cause of Merlin being u/s is the lack of spares.
I have been involved with cannibalizing a rotor head which had less than 40 hours in it.
The only way we could get spares was by using the D state routine. Then we would get the item from Westland.

I always thought the spares were sat on the shelf ready for use but not signed as serviceable until we needed it. Once the D state demand had been used Westland could charge more for the spares.

Yes, cannibalisation of Merlins is so rife, serious questions were asked.
But the problem is, cannibalisation is the effect, not the root cause of U/S cabs.
Keeping enough spares on everyone’s shelves to avoid that would be tres expensive, and would raise eyebrows at the high level of holdings - and you still have the Merlins stubbornly high unreliability, thanks to a very flawed original design process that did stupid things like add an extra engine to an originally twin engined design, purely to save a few quid getting civilian certification on a bigger engine.
‘Needlessly complex’ is probably the kindest thing you can say about it.
 
Reliability of deployed aircraft might be considered the number of sorties completed divided by the number of sorties planned.

R = Ns/Np

Ns = number of sorties achieved.
Np = number of sorties planned.

Do any open source statistics exist for Merlin HM2?

Availability is the proportion of the fleet that can be deployed on any given day:

A = Ad/At

Ad = number of deployable aircraft
At = number of aircraft in total

It follows that a very reliable aircraft (or other system) can have good reliability, due to good design, manufacturing, maintenance, and flying, but low availability due to constraints in terms of spares. I think this is what the FE@R concept is all about.

Conversely an aircraft could have good availability (lots of spares and so on) but low reliability as significant numbers of sorties need to be abandoned or cancelled as the aircraft is stuck on deck or develops fault whilst flying.

I am thinking of the eight RH-53s that took of from USS Nimitz for Operation Eagle Claw. All eight launched - so that was 100% availability. One turned back, another had a fault warning and landed, and a third developed a fault. Hence a reliability of 62.5%. Of course five aircraft was not considered enough to continue the mission, and then there was a tragic accident with a Hercules tanker.

Since the number of aircraft that can be deployed in a single unit will be relatively low (I am thinking of the single aircraft aboard a frigate or RFA, or nine aboard a carrier (in future) it makes sense to make the aircraft as reliable as possible. Redundant systems,belt and braces design, everything checked and double checked, aircrew and maintainers trained as well as possible so that on the day they can deliver. However, this probably means lower availability as spares mean cash.

@jrwlynch over to you!

PS Surely weight limitations due to the gearbox are more of an issue for load carriers? A troop carrier at altitude has greater problems than a Pinger at or near sea level.

PPS When Merlin was ordered, was there any other ASW helicopter with the same endurance on the market?

PPPS Would a Bristows (I thought they got bought out?) cab aboard an RFA be able to legally carry out an ASW, ASuW, ISTAR, or amphibious assault sortie?
How does that work if you've got say 10 '53s, you really want 9 on the op, but two are long term tits, so you only planned the op with 8. 9 would have been ideal, but you knew those two were hangar queens. Of the 8 you think you have for the op, all are generated and launch, so is that 100% availability, or 80%?
 

Yokel

LE
I suspect someone else can explain it better. In the case of Eagle Claw (or was it Eagle's Claw?) the planners asked for eight RH-53Ds. This could be achieved which is why I said the availability was 100%. the Delta Force planners had determined the a minimum number of six was needed to determine the operation. The reliability was poor - a combination of maintenance crews not fully up to speed with aircraft type, problems due to unexpected sandstorms, and so on.

I cannot remember the equations relating mean time to fail and mean time to repair, and number of units, but yes a safety margin is built in. Without a huge amount of statistical evidence the amount is hard to predict, hence you make every effort to prevent failures.

Example: ten missiles each have a 95% probabilty of successful launching. What is the probability they will all launch? 0.95^10 = 0.59 approx.
 

Yokel

LE
I suspect someone else can explain it better. In the case of Eagle Claw (or was it Eagle's Claw?) the planners asked for eight RH-53Ds. This could be achieved which is why I said the availability was 100%. the Delta Force planners had determined the a minimum number of six was needed to determine the operation. The reliability was poor - a combination of maintenance crews not fully up to speed with aircraft type, problems due to unexpected sandstorms, and so on.

I cannot remember the equations relating mean time to fail and mean time to repair, and number of units, but yes a safety margin is built in. Without a huge amount of statistical evidence the amount is hard to predict, hence you make every effort to prevent failures.

Example: ten missiles each have a 95% probabilty of successful launching. What is the probability they will all launch? 0.95^10 = 0.59 approx.
This talk of probability reminds me of the dictum Kill the Archers, Not the Arrows. The navies that have opted to have carrier based fighters have this in mind. Not everyone agrees such as Easy Street on PPRuNe:

With modern technology the best way is to ignore the launch aircraft and deploy an effective, sustainable counter-missile capability.

Kill the Arrows not the Archer? He talks about speed/time/distance with respect to the F-35B but then thinks it is more effective not to splash the missile armed aircraft but wait until the missiles are in range of ship based missiles? @jrwlynch

Also @Magic_Mushroom might not be impressed by: i

investing so much in a capability inevitably creates political pressure for it to be used for something. See also: fast jets doing 'drone' work in the Middle East.

He also seems to have missed my point about ASW (on the same page).

Sort him out! I would, but I have to shoot off to meet someone. I will return later to try to educate said person.
 
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jrwlynch

LE
Book Reviewer
With modern technology the best way is to ignore the launch aircraft and deploy an effective, sustainable counter-missile capability.

Kill the Arrows not the Archer? He talks about speed/time/distance with respect to the F-35B but then thinks it is more effective not to splash the missile armed aircraft but wait until the missiles are in range of ship based missiles? @jrwlynch
The earlier you can break the "kill chain" the better. What's often overlooked is the value of shipborne fighters for taking out enemy recce: when all they know is "there's a carrier out there somewhere, and our scouts don't come back from this general areas so it's probably around there..." it's not easy to launch a co-ordinated strike when you've got only a vague idea of where your target might be.

Similarly, a co-ordinated strike with scouts, SEAD, and strikers is a nasty threat - but if the scheduling's been spoiled because different groups were dodging Meteors on the way in, that helps the ships defending (and extra warning time means more chance to optimise ASMD stationing, course and speed, and to get confusion and distraction measures in place.)

Then, there's the point that (for instance) a Su-35 can handily carry four AS-17 missiles; I'd rather splash one aircraft than have four supersonic missiles to deal with (not that we can't, but it burns through the magazine faster than you'd like). Even a failed engagement where the enemy evades and escapes, means they've jettisoned their expensive ordnance and that's four fewer missiles reaching the MEZ.

The fighters aren't likely to obliterate the entire raid, but they can make it a lot easier to survive.
 
Apart from the fact the Russians had a dastardly way of getting around that: multiple Regiments of aircraft per carrier, and an avowed "kamikaze" strike package whose entire reason d'etre was to find the carrier via the medium of being shot down.

And then they developed a whole host of methods of automating over the horizon targeting so that it was genuinely useful.

Bastards - didn't they know they were supposed to lose by 1400 on a Thursday?
 
Apart from the fact the Russians had a dastardly way of getting around that: multiple Regiments of aircraft per carrier, and an avowed "kamikaze" strike package whose entire reason d'etre was to find the carrier via the medium of being shot down.

And then they developed a whole host of methods of automating over the horizon targeting so that it was genuinely useful.

Bastards - didn't they know they were supposed to lose by 1400 on a Thursday?
Dashed unsporting. It's almost as though the Russians have never played Cricket!
 
Dashed unsporting. It's almost as though the Russians have never played Cricket!
One of the big Russian shipkillers is designed to fly in a data linked salvo to help defeat the missile umbrella. Point missile pops up to find the target and the others stay low following its targeting, if the lead missile gets hit, next one steps up as point man.
 
Death to the Heronians!!!!
 
One of the big Russian shipkillers is designed to fly in a data linked salvo to help defeat the missile umbrella. Point missile pops up to find the target and the others stay low following its targeting, if the lead missile gets hit, next one steps up as point man.
So what happens if all the missiles get splashed do the usn et al get to splice the mainbrace or prepare for the next wave of incoming…...
 
So what happens if all the missiles get splashed do the usn et al get to splice the mainbrace or prepare for the next wave of incoming…...
In the RN:
Much wiping and re-writing of stateboards, ‘one all round’ and then channel night. Any mess afterwards can be cleaned up by a link-16’d to the max Merlin, that can do everything from flying uncomfortable for rear facing crew flight profiles to...doing the dishes via DL :)
 

Yokel

LE
The earlier you can break the "kill chain" the better. What's often overlooked is the value of shipborne fighters for taking out enemy recce: when all they know is "there's a carrier out there somewhere, and our scouts don't come back from this general areas so it's probably around there..." it's not easy to launch a co-ordinated strike when you've got only a vague idea of where your target might be.

Similarly, a co-ordinated strike with scouts, SEAD, and strikers is a nasty threat - but if the scheduling's been spoiled because different groups were dodging Meteors on the way in, that helps the ships defending (and extra warning time means more chance to optimise ASMD stationing, course and speed, and to get confusion and distraction measures in place.)

Then, there's the point that (for instance) a Su-35 can handily carry four AS-17 missiles; I'd rather splash one aircraft than have four supersonic missiles to deal with (not that we can't, but it burns through the magazine faster than you'd like). Even a failed engagement where the enemy evades and escapes, means they've jettisoned their expensive ordnance and that's four fewer missiles reaching the MEZ.

The fighters aren't likely to obliterate the entire raid, but they can make it a lot easier to survive.
I know. The poster I quoted does not have defence in depth imprinted in his brain as much as some of us. Why does he qiote Boyd and the OODA loop regarding F-35B not having enough range, but then says ships are better fighting at close range? Muddled think - the sort that got ships sunk and sailors killed in 1982.

Why does everyone seem to think the next hot war will be against Russia or China? There are lots of potentially hostile nations buying their kit...
 
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So what happens if all the missiles get splashed do the usn et al get to splice the mainbrace or prepare for the next wave of incoming…...
Incoming in close salvos of up to 8 at Mach 2+ are a rather tough ask for older fire control systems and semi active missiles.
 
Incoming in close salvos of up to 8 at Mach 2+ are a rather tough ask for older fire control systems and semi active missiles.
Come on SOI you’ve won mastermind every year since Jim Bowen splashed his Tabbac cologne on you.
 

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