Almost made-its: HS1154

[starviking]

Hi,

I've been thinking about the aircraft projects that almost made it into production, but were cancelled before they could prove themselves. Projects like the Douglas Missileer, TSR2, HS1154.

I've seen threads that ask opinions on which project should have been built http://www.secretprojects.co.uk/forum/index.php/topic,32.0.html and lots of general musing, but with this thread I'd like to gather options on what would have happened if one of our favourite projects had been ordered - would it have been successful?; had problems in development?; succeeded in a niche market?; had to be cancelled?; etc.

Looking to one of my favourite planes, the Hawker 1154 - what happens if it is ordered? I'm thinking we should keep things as close to real life as possible, so we're talking about the 1154RAF - the RN have gone for for F4s as they did historically.

They're probably going to have to drop the VTOL and go for V/STOL as in real life. That probably means less problems with hot gas re-ingestion in take-off. For landing there's probably a need to develop a 'rolling-landing' to avoid the re-ingestion problem.

Are there any show-stoppers? Will the Hawker 1154 be successful? Could it feature in 'The sale of the century'? Let me know what you think.

Starviking

 

[starviking]

"Bueller?... Bueller?...Bueller?"

No takers? :'(

Starviking

 

[Jemiba]

Well, you're right, this question deserves an answer, here's my attempt :

The RN needed a supersonic interceptor, with secondary ground attack capability, for the
RAF it was just the other way round. Supersonic capabilities weren’t mandatory for a ground
attack aircraft, so, why pay more money for it, then for a standard Harrier ? The value of a
VTOL/VSTOL aircraft wasn’t regarded that high in NATO in general and in especially not in GB,
I think. It was the USMC, which really opened the door for the Harrier. And as the development
of the AV-8B has shown, the way was towards higher payloads, not higher speeds, so I don’t
think, that the USMC would have jumped the P.1154-waggon.
I like this aircraft, too, but I think, if built, the prototype would have just been an interesting
aircraft on the Farnborough airshow, but not a bestseller. Maybe the maritime version would
have done better, offering a real fighter aircraft to navys, that couldn't afford large carriers,
but this was out of question here ...
The HS.1154 was a good product for too small a market !

 

[avatar]

yup the Indian navy would have lapped it up.

 

[starviking]

The RN needed a supersonic interceptor, with secondary ground attack capability, for the
RAF it was just the other way round. Supersonic capabilities weren’t mandatory for a ground
attack aircraft, so, why pay more money for it, then for a standard Harrier?

While supersonic capability isn't considered vital for ground attack, it is still nice to have. In the Supersonic Sixties it was virtually required. If you look at the aircraft the RAF got or wanted to get we have the Jaguar Attack, Jaguar Trainer, TSR-2, F-111, AFVG, UKVG and Tornado. There was the Buccaneer, but it was more-or-less forced on the RAF.

If the HS1154 did get ordered it'll probably fill the role that the Jaguar did in the Attack stakes.

The other thing is that the HS1154 was the production programme, Kestrel was for trials. If HS1154 goes ahead - the P1127 Harrier as we know it will probably not see the light of day.

The value of a VTOL/VSTOL aircraft wasn’t regarded that high in NATO in general and in especially not in GB,
I think. It was the USMC, which really opened the door for the Harrier. And as the development of the AV-8B has shown, the way was towards higher payloads, not higher speeds, so I don’t think, that the USMC would have jumped the P.1154-waggon.

I don't know about that. At the time of the programme VTOL was all the rage. There was the NATO Programme for a VTOL Strike-Fighter (NMBR-3), to which Dassault, Hawker-Siddley and Fokker-Republic put in bids. Germany was also dabbling with the EWR VJ 101 and the VFW VAK 191. Historically these were inconclusive. A successful or semi-successful HS1154 might have changed things.

Also, I think the UK was pretty proud of it's achievements in VTOL. In the 70's we had a host of RAF adverts on TV touting the unique capabilities of the Harrier.

As to the USMC - would they be interested in it for Vietnam. I remember reading that they went for the Harrier as it could be operated close to the battlefront. Would that hold for the HS1154? Also, could the Iwo Jimas operate them?

I like this aircraft, too, but I think, if built, the prototype would have just been an interesting
aircraft on the Farnborough airshow, but not a bestseller. Maybe the maritime version would
have done better, offering a real fighter aircraft to navys, that couldn't afford large carriers,
but this was out of question here ...
The HS.1154 was a good product for too small a market !

Well, there's no stopping the HS1154 RAF being used from carriers, the USMC did use their Harriers from their flat-tops after all

Perhaps the HS1154 could have lead the way to an earlier AV-16 in the 70's?

Starviking

 

[Rickshaw]

The utility of the 1154 would have been more limited than the Harrier. It would have needed to operate from hard standings. The advantage of the Harrier was that its exhausts were relatively cool and so it was possible to operate from PSP runways and pads (although the preference was always to operate in STOL rather than VTOL mode because of the fuel that was used up in hovering with full load). The 1154's exhaust was appreciably hotter, particularly with plenum chamber burning (reheat effectively). It was hot enough to melt runways and ship's decks and if you were going to try and take off at full load, you would have needed PCB. As the load for the 1154 wasn't that appreciably greater than the Harrier, the Harrier was always IMO a better choice over the 1154 in the long run. Just one of those odd counter-intuitive points which sometimes pops up in military weapons systems.

What I've always though was a bad design aspect of the Harrier was the relatively small size of the airframe and in particular the nose. If they'd built in a larger nose and cockpit from the start, even if it was empty, it could always have been filled at a later date when more powerful Pegasus engines came along. Instead, we've had successive attempts to try and shoehorn in more and more equipment into a much too small a space.

 

[avatar]

What I've always though was a bad design aspect of the Harrier was the relatively small size of the airframe and in particular the nose. If they'd built in a larger nose and cockpit from the start, even if it was empty, it could always have been filled at a later date when more powerful Pegasus engines came along. Instead, we've had successive attempts to try and shoehorn in more and more equipment into a much too small a space.

we can't have everything now, can we. VTOL necessarily meant that you had to keep the *weight* down. Now in those days they didn't really have composites .. so there's your trade off right there. even with the more powerful pegasus engines .... radar weight and power requirements would have been constraints. That is precisely why the IN retrofitted a ski jump on the Viraat . VTOL increasingly became difficult to use as an operational capability as the shoe horning progressed.

 

[Weaver]

Wonder what would have happened if they'd dumped PCB and just used the dry BS100 to build a bigger, subsonic Harrier...........

 

[avatar]

in all likelihood ... you would have got an even more "subsonic" harrier.

 

[zen]

IF HS1154....

Well the issues of PCB where already becoming aparent during testing the BS100 which is why there is reference to a "rolling VL" to escape the hot exhaust gases. Compromise is the name of the game, swapping aluminium planking for steel for example.
No F4 for the RAF or Jaguar under this scenario.

The RN will be in a very curious position, the 1154 can operate from carriers and can operate quite well if their modified to its requirements (pierced landing grids and a ski-ramp), but this runs counter to the requirements of CTOL aircraft.

Lord Carringtons CV proposal comes to mind of course.

 

[Weaver]

in all likelihood ... you would have got an even more "subsonic" harrier.

Why?

The Pegasus in the first Harrier GR.1 produced 19,000lb.

The Pegasus in the current Harrier GR.9 produces 23,400lb, an increase of 23%. This is the most powerful in-service version, but there have been much higher-thrust Pegasus variants, both built and projected, available much earlier.


The first BS100 produced 35,900lb with PCB, 26,200lb dry; that is to say, the first BS100 produced 2,800lb more dry thrust that the last Pegasus.

Bristol Siddeley projected that they would be able to get 39,250lb with PCB from the BS100 by 1972. It's hard to say how much of this increase would have applied to the dry thrust rating, but it would surely have gone up significantly. If they only achieved the 23% increase possible with the Pegasus then the BS100 would be giving at least 32,200lb by now: not far off the PCB thrust of the original engine.

(edited 21apr08 to put thee words in the right places but not change any of them....)

 

[Rickshaw]

IF HS1154....

Well the issues of PCB where already becoming aparent during testing the BS100 which is why there is reference to a "rolling VL" to escape the hot exhaust gases. Compromise is the name of the game, swapping aluminium planking for steel for example.
No F4 for the RAF or Jaguar under this scenario.

The RN will be in a very curious position, the 1154 can operate from carriers and can operate quite well if their modified to its requirements (pierced landing grids and a ski-ramp), but this runs counter to the requirements of CTOL aircraft.

Lord Carringtons CV proposal comes to mind of course.

CTOL aircraft we know now, can indeed use ski-jumps. You don't think that would have been found out a lot earlier? It would be quite possible to create a retracting ski-jump BTW.

 

[Jemiba]

"It would be quite possible to create a retracting ski-jump BTW"
Well, but would there still be benefits with regards to weight, internal volume
and complexity against a catapult ? ???

 

[Rickshaw]

The point I was attempting to make was that there will always be compromises in any design. If you want a ski-jump but also want a catapult, its possible to have both, if you're willing to accept the compromises.

 

[zen]

Compromises indeed. Mixing CTOL with STOVL in carrier design is no easy task, since the ideal VL location is right slap bang in the way of the angled deck run, and the run up to the ski-ramp also is longer than a catapult run and gets in the way of the angled deck, so the question has to be which has more priority in operations, the CTOL aircraft or the STOVL aircraft.

Mixing the two is the worst of all worlds.

For the RN at the time even if they had considered the use of Ski-ramps and landing grids for the HS1154 their offensive power is still in the Buccaneers, which are CTOL and far more capable of the ranges and payloads the RN desires.

Retracting ski-ramps sound fine, but its more moving parts and thus more maintanence, countering one of the advantages of STOVL.

 

[Rickshaw]

Why not have a wider flightdeck and have both, side by side? Alternatively, if you increase the length of the flight deck, you overcome most of your objections to the use of a ski-ramp. I also find it interesting that you believe its impossible to alternate landings and take-offs so that it would be possible to utilise both the angled flight deck and the ski-ramp.

Out of a matter of interest, what happens if you combine a ski-jump with a catapult?

 

[zen]

Side by side as in a Parallel deck?
Shades of CVA-01 perhaps or some of those US studies and artwork I've seen (some here I think).
The whole point of an angled deck is that you clear the forward part of the carriers flightdeck for aircraft to be parked or even free to launch as you land aircraft. Simultaniously launching and landing.
For a parallel deck assuming you are landing on one side and launching on the other you will need quite a width of deck to fit the two on for the same thing.

Increasing length is indeed the other way forward, but why do that for STOVL? Your driving up the length or the width of the carrier to try to fit STOVL and CTOL on the same deck, but the bigger your CV the more capable it is as a pure CTOL carrier.

Alternating landings VL and conventional is fine in theory, but precise timing it likely required, and it pushes the STOVL aircraft further away from the CV to stay safe while CTOL aircraft are landed. Interleaving these types of landings seem a receipe for disaster IMO, better to have distinct phases of landing a number of CTOL aircraft and then switching to landing STOVL aircraft. But it still seems a very complex way of doing something.

STOBAR (Short take off and arrested landings) is the worst layout of a carrier deck, taking more area away from the deck and restricting deck parking area than any other other option.

 

[Rickshaw]

You misunderstood me. When I spoke of "parallel" things I meant launchers. Why not place a ski-jump beside the catapult?

However my main point is better yet - why not place the catapult on the ski-jump?

Oh, and in fact the main reason why angled carrier decks were introduced was to allow the carrier to land on aircraft without any danger of them crashing into the parked aircraft forward - something quite important when memories of the Seafire and Corsair were still fresh in the minds of the designers.