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-   -   Shipboard Rolling Vertical Landing - The saviour of Dave-B? (https://www.pprune.org/military-aviation/340021-shipboard-rolling-vertical-landing-saviour-dave-b.html)

WhiteOvies 30th Aug 2008 11:15

Not to mention the Osprey landing on CVS just to prove a point last year.

Probably discussed before but what would happen if you fitted Carson blades, 5 blade TR and new engines (all proven in SK HC4+) to an ASAC7? Not that we could afford it of course!

Not_a_boffin 30th Aug 2008 11:37

The bag is actually doing a role more akin to ASTOR / MRA than the original AEW intent - and no bad thing either! However, a significant and important part of the MASC role involves not just AEW, but C2 of offensive force packages, which means better performance than you'll ever get from a pure helo, both in terms of ceiling but more importantly speed and endurance.

Hawkeye can provide the required platform performance, but the mission system performance is reputedly poor and doesn't do the things that the bag does well at the minute.

Sticking the Searchwater on the V22 would go some way towards a compromise between the two extremes, but at what cost? Development, design modification, production of (say) a dozen airframes for the RN and logistic support of same would be far from cheap. Would the current "bag radome" need streamlining to deal with the higher Vmax, and or strengthening the support structure? All allied with an ingenious but fiendishly complex power tx system between the engines that would also have to have generators modded to supply the watts to the mission system.

Nice thought, but unless someone stumps up serious wedge very soon, it ain't going to happen.

Engines 30th Aug 2008 19:48

A few years ago, Westlands put forward a proposal for a 'compound 101' with stub wings, augmented exhausts and a combined power/flight controls system to provide better speed/height/endurance for an 'AEW/MASC' solution. Anyone know anything more about this one?

In the meantime, Carson blades and uprated engines for the ASACS 7 might very well need to be the stop gap. Just money, right?

The V-22 solution described earlier was designed to be palletized and allow a standard V-22 to take the radar fit fairly quickly, using the ramp aperture to deploy the dome. Not sure that the comms and power requirements wouldn't have led to a special airframe in any case, though.

That said, the Osprey really could offer a very neat solution in terms of speed and endurance. Costly, though.

best Regards as ever,

Engines

Squirrel 41 30th Aug 2008 20:57

Engines, N-a-B;

As ever, very interesting. The V-22 idea was debated here sometime ago, and IIRC there was also an issue with the lack of pressurisation and, cost. Which was reputedly massive. (Mahoosive, in fact). For a maximum of 12 aircraft, getting the altitude performance and radar integration work done seemed to provide a range of numbers from the shockingly high to the truly absurd. However, if we could expand the customer base, then at least the engineering amortisation would be spread further - which leaves Spain, Italy, Thailand and India as possibles with little carriers and a potential MASC requirement.

(Though I heard a rumour that the Spanish Armada have probably permanently binned their Bagged Sea Kings; sad, if true).

Presume that discussions are on-going with these, and other - USMC? - air arms about a joint programme? This is a rumour site after all....:E

S41

Jetex Jim 2nd Sep 2008 10:03

Before this thread drifts right off the radar, maybe its worth one more bump.

The UK's commitment to STOVL, which ensures high level industry participation in JSF-B, neccesitates a ski-jump carrier. A ski jump carrier, neccesitates a rotary wing 'AEW/MASC' solution. Both STOVL aircraft and rotary wing 'AEW/MASC' will have less capability and be more expensive than non STOVL aircraft and fixed wing 'AEW/MASC'. The new carriers, unlike the RN current boats, are large enough to support CAT/TRAP operations.

STOVL can apparently be justified, though not with any figures in the public domain, on the grounds that STOVL training/currency is much easier than cat trap operations.

Interesting to read, in
Navy Matters | Future Aircraft Carrier Part 12
That back at the time of the Phantom/Bucc; cat trap ops were considered no big deal, in fact the 1964 Defence White paper assumed that RAF Phantoms would operate from the carriers too!

At the time, the 'High price help' were arguing the opposite case, in order to support the Spey Phantom, as their succesors are now arguing to justify JSF-B.

Interesting or what?

John Farley 2nd Sep 2008 11:56

Jetex Jim


That back at the time of the Phantom/Bucc; cat trap ops were considered no big deal, in fact the 1964 Defence White paper assumed that RAF Phantoms would operate from the carriers too!
I don't feel that attitudes (and indeed facts) from the past can be used as simply as that to justify actions today.

For example below are the fatalities suffered by the RAF in the early 50s when their only war ops were Sunderlands in Korea. They are therefore effectively peacetime figures. At that time to use your phrase these losses were "no big deal" and certainly coroners and lawyers were not involved.

Year
1950 380 238
1951 490 280
1952 507 318
1953 483 333
1954 452 283
1955 305 182

The first column is aircraft lost and the second total fatalities

I would not expect to argue today that such figures show (for example) the current discussion about a single Nimrod accident is unreasonable. Times really do change and with them people's attitudes and reasons for what they do.

JF

Simmbob 2nd Sep 2008 16:21

Year
1950 380 238
1951 490 280
1952 507 318
1953 483 333
1954 452 283
1955 305 182

The first column is aircraft lost and the second total fatalities

Rather sobering statistics!

Engines 2nd Sep 2008 19:05

JJ,

One more bump then -

The UK has not 'committed to' STOVL - we are still officially in 'wait and see' mode', although STOVL is stated as our 'preferred option' - clear as mud, right? Basically, my view is that we are hedging our bets in case the F-35B falls over big time. My view is that it won't. I might be wrong and others will differ.

Assertions and facts - 'high level industry participation in JSF' is not a direct link to UK buying STOVL. Yes, RR get lift fan work, but they have a good stake in the F136, which could go in all variants. BAES are building bits of all three variants, MB are supplying all the seats.

Cost of F-35B against F-35C, for the same capability, just isn't known with certainty. We do know that C will be the most expensive variant. 'Capability' of a CVF with its air group is not easy to quantify, but there have been studies by respected organizations (actually quoted in the link you provided) that point to very good 'bang per buck' for advanced ASTOVL equipped ships. And one thing is certain - we are going to have less bucks to play with than the USN.

As ever, John Farley is bang on the mark - current requirements for safety and public attention to loss rates would make a move to the very skill intensive world of cat and trap an expensive business (and don't forget the costs of training the deck crews and ships company as well)

This has been a really enjoyable thread,

Best regards

Engines

Jetex Jim 2nd Sep 2008 20:43

Engines

The UK has not 'committed to' STOVL - we are still officially in 'wait and see' mode', although STOVL is stated as our 'preferred option' - clear as mud, right? ...Assertions and facts - 'high level industry participation in JSF' is not a direct link to UK buying STOVL.
Well that's clear enough, but the CRS report to congress; dated October 25 2007 puts a rather different slant on it.
http://www.fas.org/sgp/crs/weapons/RL30563.pdf explicitly says

..The costs and complications of pursuing the STOVL variant (including reducing weight growth) are leading some to suggest that the JSF program would be more feasible and more affordable if the F-35B were cancelled. In this case, the Marine Corps would buy the CV JSF instead of the STOVL variant. ...Others point out that cancelling the STOVL version of JSF is complicated by the United Kingdom’s investment in the program and its requirement for a STOVL aircraft...The United Kingdom needs the STOVL design to operate off their aircraft carriers and only plans on purchasing the STOVL design for both their Air Force and Navy.
In addition the UK is identified as the only 'Tier 1' participant, with a 2 Billion investment in the project.

JF
Yes indeed, things have changed since the 50s, and a good thing to. However, it would be interesting to see what actual Ark Royal F4 Bucc losses were in the 1970s.

cheers JJ

airborne_artist 2nd Sep 2008 21:22

According to NAVAL-HISTORY.NET there was only one fatal loss of an embarked (probable) two-seat aircraft from the Ark in the 70s;

Sunday, 3 May 1970

Ark Royal, air crash in English Channel
COOMBES, Phillip J, Lieutenant
STEWART, Alexander, Lieutenant

Schiller 3rd Sep 2008 12:21

Deck landing isn't that difficult (after all, quite a few Crab pilots were taught how to do it), or dangerous, even without intensive practice. During the 60-70's, although the loss rate was high-ish, very few accidents were directly due to carrier landings or launches.

Brain Potter 3rd Sep 2008 14:24

To reduce the shipborne training burden could the routine deck-landing of F-35C be left to automation?

If manual deck-landings were regarded as a reversionary mode then perhaps line pilots would then only practice them in a simulator, with a recurrent dual-check from a small cadre of instructors qualified in live deck-landings.

Pilots are going to have get used to the idea of automatic ejection on the F-35B so perhaps reliance on automatic landings doesn't seem so radical.

LowObservable 3rd Sep 2008 16:30

CV autoland is a huge part of the Navy's X-47B unmanned combat aircraft program, but won't be demonstrated until 2011.

If the program survives, and if it works, the effect on CV aviation is vast. Why so? Because the requirement is that automatic landing should be at least as safe as a piloted landing at all times.

And if the GPS and computers do as well as the pilot on a clear, calm day, they will inevitably do better on a rainy, windy night, because they sense deviations and make corrections at a much higher cycle rate, and because the system uses GPS and neither knows nor cares that it can't see the lights.

It's also a system that is not hard to retrofit to any fly-by-wire airplane.

However, the RN has to make its decision before we know whether it works...

Jetex Jim 4th Sep 2008 05:35

CV autoland

Originally Posted by LowObservable
...if it works, the effect on CV aviation is vast. ...However, the RN has to make its decision before we know whether it works...

Yes, dashed bad timing that.

I keep forgetting that the RN hasn't, officially, decided between Dave B or Dave C yet. Must be that darn Congressional Research Service report, cited above, that insists that the UK has already commited to JSF-B...

LowObservable 4th Sep 2008 16:21

Right you are, JJ...

All the apparently knowledgeable froods here insist that the UK's position is officially undecided and that there is an exit ramp from STOVL, maintained in place on the far side of STOVL flight testing. As far as I can tell it would mean extending Big Lizzie's phase of Harrier GR9 operations, incorporating cats on Chucky from the get-go, and building cats into the first carrier at the first refit.

On the other hand, the JSF program foams at the mouth at the very suggestion of such treachery, because there is no alternative to Dave B for the Marines. Take away the UK's B order, and the Marine jets start to look very expensive.

Engines 4th Sep 2008 18:16

LO,

The UK position on STOVL vs. CV is, I absolutely agree, less clear than it could, or should, be. I'd expect a more positive posture soon in response to the JSFPO's request for firm commitments to production numbers.

The UK's B order is important, but the fact is that if it doesn't technically work for the UK, it wouldn't for the USMC. If the UK cancelled for another reason, the USMC would still, in my view, get their Bs. They are absolutely committed to the project, and their track record shows that when they want a piece of kit, they usually get it.

Auto landings - I'll repeat my thoughts. The USN are developing, testing and qualifying F-35C to fit in with their recovery CONOPS, which call for a primary ability to land the thing manually, with JPALS (Joint Precision Approach and Landing System) as a 'recovery aid'. USN is using existing ACLS more than it did before as amount of night flying goes up, but mostly as an aid to glide slope acquisition and initial lineup - I am told almost all landings are still manual to allow pilots to retain their deck proficiency ratings.

In my view, the chances of JSF going to auto-land as a primary recovery mode to the deck are slim. Chances of the USN drawing down on landing training and relying on it are almost nil. If the UK wanted to go against that policy, there would be big money involved.

Still a good thread, this one....

Best regards as ever

Engines

Mr-AEO 4th Sep 2008 21:53

Engines,

In addition to the ability for an increased bringback which is good, is it also the case that we are avoiding burning a sodding big hole in the deck each time we land (as might be the case from a pure Vertical Landing??).

If so, which one is the real driver for the SRVL?

Also, I don't believe that we can ever 'hand on heart' say that an SRVL is as safe as the purely VL recovery. As has been said, if you hit one wheel on that single oily patch at night, massive brakes or not, you risk 'kerbing' your shiny jet down the flight line or worse if aircraft laden with weapons are involved!

As for bolter, I think that a V22 with a fat tank sat in the circuit would be quite useful for that situation; the rest of the embarked V22 flight could have a radar/mission system and fulfil the MASC role. Not to mention a big space for returning the u/s 'Lightning' powerplants.

Jetex Jim 5th Sep 2008 12:35

I suppose one could say that regardless of any 'hidden' costs of JSF B, the payback to BAE and RR will still be huge. These companies, thanks to that 2 Billion dollar tier 1 buy in, and what seems to be a commitment to support the case for the STOVL version, come what may, now get to manufacture about 1/3 of all JSF types, at the very least 2000 planes.

So UK armed forces get a couple of big ships, some new aircraft. And maybe they are not exactly optimum but look how much good it does industry! And what's good for BAE and Rolls Royce has got to be good for the UK exchequer – the jobs created, trickle back income tax and other taxes, right ? So stop gripping and just 'Rejoice Rejoice'.

Well maybe. Back in the day, such a deal would have been an unqualified success. Now we have globalised industry and both BAE and RR have production facilities in the USA. RR employ over 8000 people in North America, and BAE 43000. Couple that with the Buy America Act and we have to start wondering just how much of that 1/3 of 2000 will actually get manufactured in the UK?

Well, the UK plans to acquire about 140…

LowObservable 5th Sep 2008 15:15

I believe that BAE's biggest piece of JSF will be made in USA: the EW system.

LowObservable 5th Sep 2008 15:22

I too would be surprised if the USN committed to automatic landing for its carrier aircraft, even if the conservatives don't succeed in killing UCAS-D and the program demonstrates autoland successfully.

But it's a pity, because the USN spends a lot of money replacing aircraft that have been flogged to death practicing carrier landings - the lifetime of a Super Hornet seems to be about 17 years, with the type headed for a OSD in 2030 (is that why the export market's not excited?), which doesn't compare too well with the EPAF F-16AMs.

I'd never be too surprised if France, or India, were the first to go autoland for their carrier operations.


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