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Odie
3,702 posts
52 months
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MartG said: Odie said: apasrt from the harriers age, what were the disadvantages of it as a carrier borne aircraft? The USMC don't seem to think it has any issues, as they are quite happy to continue operating it from their carriers ( and buying our old ones for spares ). italy, spain and india seem happy too. What about one of this as a harrier replacement http://en.wikipedia.org/wiki/Bell_XF-109
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Scuffers
10,503 posts
144 months
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MartG said: The USMC don't seem to think it has any issues, as they are quite happy to continue operating it from their carriers ( and buying our old ones for spares ). yes, but they are used in a different role to their 'main' aircraft carriers, as in close support as opposed to long range attack or air defence. Harrier good as it is, is no replacement for Hornet's or the new F35B
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hidetheelephants
5,711 posts
63 months
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Scuffers said: rhinochopig said: If you're talking about the x-32, that too used a lift-fan but powered by the main engine. The big issue with X-32 was the wing design.
A lift fan is certainly not an elegant solution. It serves no purpose beyond being used for small percentage of the flight envelope and yet has a big penalty in terms of weight and space 100% of the time. sorry, the X-32 did not have a lift fan, it used the engines thrust alone (like the Harrier) hence the engine being well forward in the design (I assume your trying to suggest that the inlet 'fan' of the engine is a lift fan?) point is that the lift fan solution means that the design is less compromised by having the engine in a better place for normal flight, if you remember, the X-32 never achieved supersonic flight and was grossly over-weight to the point when it did achieve vertical takeoff, it had to have some 2,000Kg's of stuff stripped off it. this is worth watching: http://www.youtube.com/watch?v=7WnQROVmik4http://www.youtube.com/watch?v=ukbr2UtzH3Y On the other hand, the X32 was a far more conservative design technically and stood a good chance of being on time and within budget; which is better, late and overambitious(F35B still not in service, still overweight and going up in price daily) or in service, on budget and moving mud but plug ugly? That footage is of a prototype lashed together to show politicians something that flies, of course it's overweight compared to the project objectives; F35B is still a porky f  ker and it ought to be in operation by now.
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Ian Lancs
578 posts
36 months
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hidetheelephants said: On the other hand, the X32 was a far more conservative design technically and stood a good chance of being on time and within budget; which is better, late and overambitious(F35B still not in service, still overweight and going up in price daily) or in service, on budget and moving mud but plug ugly? That footage is of a prototype lashed together to show politicians something that flies, of course it's overweight compared to the project objectives; F35B is still a porky f ker and it ought to be in operation by now. X32 was such a conservative design it couldn't meet the fly away tests without having to undergo some cosmetic surgery. Boeing also admitted that they'd need to rewing the aircraft before production - thats not a good thing to have to do during a development prog
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hidetheelephants
5,711 posts
63 months
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Ian Lancs said: X32 was such a conservative design it couldn't meet the fly away tests without having to undergo some cosmetic surgery.
Boeing also admitted that they'd need to rewing the aircraft before production - thats not a good thing to have to do during a development prog The new wing was required because the USN revised the SOR and asked for more agility; it met the original spec.
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Bedazzled
4,306 posts
91 months
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Scuffers said: Very interesting programme, thanks for posting.
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Ian Lancs
578 posts
36 months
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hidetheelephants said: Ian Lancs said: X32 was such a conservative design it couldn't meet the fly away tests without having to undergo some cosmetic surgery.
Boeing also admitted that they'd need to rewing the aircraft before production - thats not a good thing to have to do during a development prog The new wing was required because the USN revised the SOR and asked for more agility; it met the original spec. True (I should really have put that in my original post). But the x-32 still couldn't do STOVL and 1.0M+ on the same flight - that was most def. in the original requirements.
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telecat
6,264 posts
111 months
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Persoanlly I prefer some of Hawker and BAE's later designs Such as the P1205  Then there was the Very advanced P1214  And probably the best of the lot the P1216.  All Used Plenum Chamber Burning to achive Supersonice flight except the 1216 which also a "Vectored thrust Nozzle" like the F35.
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doogz
19,304 posts
57 months
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DamienB said: Construction started on Ship 2 months ago. MartG said: £1B to 'redesign' it for catapults - I thought they were already designed for them, just weren't going to have them fitted ? It had been designed with the option of fitting steam catapults. MOD have now decided they want to use EMALS instead, which is a completely different system.
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MartG
2,794 posts
74 months
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doogz said: It had been designed with the option of fitting steam catapults. MOD have now decided they want to use EMALS instead, which is a completely different system. Ah - customer changes spec at a late stage then wonders why the cost has gone up a lot
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Scuffers
10,503 posts
144 months
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MartG said: doogz said: It had been designed with the option of fitting steam catapults. MOD have now decided they want to use EMALS instead, which is a completely different system. Ah - customer changes spec at a late stage then wonders why the cost has gone up a lot Yes, all well and good, but seriously, £1B change? May I remind you that's 3 times the total bill to build MS Queen Elizabeth (about the same tonnage).
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doogz
19,304 posts
57 months
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Scuffers said: Yes, all well and good, but seriously, £1B change?
May I remind you that's 3 times the total bill to build MS Queen Elizabeth (about the same tonnage).
That's a bit like saying a Ferrari 458 is about the same weight as a VW Golf. It's correct, but not really relevant.
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Scuffers
10,503 posts
144 months
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doogz said: That's a bit like saying a Ferrari 458 is about the same weight as a VW Golf. It's correct, but not really relevant. not really, Golf is a car produced in the millions, 458 in the hundreds, they are also not make from the same materials. these ships are not mass produced, are all made from basically the same materials, using similar build methods. Yes, a carrier has some specific stuff to it just as an ocean liner has, but so what? or are you going to tell me that the carriers are made from un-otainium, and have crew quarters that are better equipped than the liner?
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MartG
2,794 posts
74 months
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And don't forget thst the £1B probably includes the EMALS system itself, as well as the associated support equipment ( e.g. f king huge generators )
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rhinochopig
16,139 posts
68 months
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Scuffers said: doogz said: That's a bit like saying a Ferrari 458 is about the same weight as a VW Golf. It's correct, but not really relevant. not really, Golf is a car produced in the millions, 458 in the hundreds, they are also not make from the same materials. these ships are not mass produced, are all made from basically the same materials, using similar build methods. Yes, a carrier has some specific stuff to it just as an ocean liner has, but so what? or are you going to tell me that the carriers are made from un-otainium, and have crew quarters that are better equipped than the liner? Coming back to your previous point. Apologies you were right WRT to the X-32 not having a lift fan - I was getting the projects confused, although I do still maintain that having a fan purely for lift is an inelegant engineering solution. The vids were interesting though although I've only watched the first part. I can offer some reasons why the costs are very different based on my experiences when we were designing (parts of) Astute. - Defence contractors have massively higher overheads than their civ equivalents. IT costs a bomb due to restricted networks, etc. Security vetting costs lots, wages are higher due to the specialist nature and lack of SQEP people.
- DEFSTANs are much harder to meet than their equivalent civil standards. EMC and g-loading requirements are higher. SIL levels for software are higher. etc. etc.
- The MoD are not averse to changing their mind mid-way through a project which can introduce massive costs if your design is predicated on an agreed assumption that is later changed.
- Much of the kit is not COTS so needs to be developed and tested from scratch by companies who all defence contractors so have the associated costs described above.
- Generally the skills are lost between designs because the workforce does not see the throughput to remain SQEP so each new project has a massive training and learning cost.
And these are just the things I can think of off the top of my head in a two minute post. I'm sure Doogz can add some BAE specific reasons too.
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Scuffers
10,503 posts
144 months
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rhinochopig said: I can offer some reasons why the costs are very different based on my experiences when we were designing (parts of) Astute. - Defence contractors have massively higher overheads than their civ equivalents. IT costs a bomb due to restricted networks, etc. Security vetting costs lots, wages are higher due to the specialist nature and lack of SQEP people.
- DEFSTANs are much harder to meet than their equivalent civil standards. EMC and g-loading requirements are higher. SIL levels for software are higher. etc. etc.
- The MoD are not averse to changing their mind mid-way through a project which can introduce massive costs if your design is predicated on an agreed assumption that is later changed.
- Much of the kit is not COTS so needs to be developed and tested from scratch by companies who all defence contractors so have the associated costs described above.
- Generally the skills are lost between designs because the workforce does not see the throughput to remain SQEP so each new project has a massive training and learning cost.
And these are just the things I can think of off the top of my head in a two minute post. I'm sure Doogz can add some BAE specific reasons too. Having worked on defence projects (for both UK and US interests), I recognise all of the above, and appreciate that there are cost penalties with defence stuff, however, getting back to the land of reality, how can a catapult system (that's already being designed and proven) possibly cost £1Bn? I mean, GET REAL. to put this in context, the Thameslink Cross-rail contract was only £1.4Bn to build and maintain 1,200 carriages. if this was private commercial money you think it would cost that much? (as well as it would have been finished and in service some years ago)
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tank slapper
7,759 posts
153 months
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That's pretty much my view - I can't see how on earth that amount of money is justified. The manufacturers are taking the piss massively and the MOD don't have the guts or negotiating ability to call them on it.
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doogz
19,304 posts
57 months
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Scuffers said: not really, Golf is a car produced in the millions, 458 in the hundreds, they are also not make from the same materials.
these ships are not mass produced, are all made from basically the same materials, using similar build methods.
Yes, a carrier has some specific stuff to it just as an ocean liner has, but so what? or are you going to tell me that the carriers are made from un-otainium, and have crew quarters that are better equipped than the liner? Well for a start, they'll be constructed from different materials. Steel, is not just steel. There are lots of different grades. Secondly, the carrier is jam packed full of incredibly modern, expensive, hi-tech equipment. I'll not go into details, but you'll just have to trust me. Some of the bits of kit i've seen so far are pretty incredible. Even some of the more boring stuff, how much do you think a pair of lifts, that'll carry 2 aircraft each, up 11m on the outside the ship, that'll still work after you've taken a torpedo or two, cost? They're not cheap. It's a ship, but it's also a floating airport, there is a lot more bespoke equipment on there than there is on a cruise liner.
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Gazzas86
764 posts
41 months
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tank slapper said: That's pretty much my view - I can't see how on earth that amount of money is justified. The manufacturers are taking the piss massively and the MOD don't have the guts or negotiating ability to call them on it. This ^^ - The same reason a company can charge the MOD £600 for a simple phone handset, i.e. similar one you could get from argos for a tenner.
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doogz
19,304 posts
57 months
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MartG said: And don't forget thst the £1B probably includes the EMALS system itself, as well as the associated support equipment ( e.g. f king huge generators ) And the fairly huge structural re-design to incorporate it all. It's possible, but unlikely, that the 2 reserved spaces for boiler rooms on 9 deck are going to be much use for the EMALS kit.
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