More Gloster VTOL Projects

[Monkeyfume]

I looked farther into the Gloster VTOL project in my last thread and found there were a few more.

Enjoy
Gloster Aircraft Company experimental VTOL designs 1958-1961 - Album on Imgur

My thoughts on it:
The 1958 entry is really an outlier
497, 504, 505, and 507 are all fighters using Rolls-Royce lift engines. Once the Harrier's design proved superior, however, Gloster started drawing up a bunch of odd transport planes, with VTOL tech in them.

I think all of the V/STOL planes in there are a lot more promising than the pure VTOL ones, the Meteor T.7 modification (Gloster P.504) actually ended up being the most outlandish.

My favorite one out of the collection has to be the P.505. It had a strong turbofan engine inside and a comparatively simple system of only four lift engines -- some other ones there that have 10 or more. The shape reminds me of a Gloster Javelin, which was already in successful production by that time. P.517 doesn't look too bad either; looks a bit like a C-130 and would probably function similarly, but with the C-130 already being readily available there wasn't really a point to it...

 

[GregP]

Thanks for that, Monkeyfume. Good find.

 

[nuuumannn]

Most of those were in-house designs, rather than being produced as submissions to any operational requirement, as interesting as they are. The transport ones look like preliminary designs to GOR351, which called for a Beverley/Hastings replacement with a STOL or VTOL capability. Armstrong Whitworth design team as part of the Hawker Siddeley group produced the HS.681 four engined high wing transport: https://en.wikipedia.org/wiki/Armstrong_Whitworth_AW.681, although I suspect Gloster design teams might have had some input. The HS.681 was cancelled on the same date as the P.1154 and TSR.2.

 

[Monkeyfume]

Wow. Never heard of it before, but it does look very similar to the Gloster P.517. And they were related to the C-130 as I assumed.

 

[nuuumannn]

Not really related, the British designs would have been more capable than the turboprop Herc. Ironically, the C-130 was selected to replace the HS.681, which would have been a more capable airframe than the Herc, granted its vectored thrust Medways. It was all political of course, being tied up with the TSR.2 programme; the HS.681 was intended to provide support for the TSR.2 at the front line. With the cancellation of the P.1154, TSR.2 and the transport, the British ordered American equipment to replace the three contentious projects; the Herc for the transport, the F-4 for the P.1154 and the F-111 in place of the TSR.2, but of course, less than three years later the RAF F-111K order was cancelled as it was turning out to be more expensive than the TSR.2.

 

[Monkeyfume]

I always thought the reason was the government didn't have the kind of money to fund all those projects while the USA did.

 

[nuuumannn]

On the face of it, that's the reason behind their cancellation, but that decision was made by a government that also claimed that a developed country needs a thriving aviation industry! Sadly however, that the projects got to a point that they became unaffordable by the nation in the first place is what muddies the waters a little. Politics, bad timing, over engineering, inter-service disputes, money worries, technical issues, overhaul of the aviation industry - all conspired to increase cost and reduce productivity on all the projects. As it was, the British aircraft would have been superior in capability compared to their American substitutes, although the F-4 could carry a bigger load and was faster than what the P.1154 was projected to be, it had its V/STOL capability, which would have proved more versatile as a carrier aircraft - see Sea Harrier carrier operations during the Falklands for evidence of this.

It's also worth remembering that the Brits had a few other aerospace projects on the go at the time, chief of which was the Concorde, although the government wanted to get out of that too, but they had signed a binding contract and couldn't. There was also the European Launcher Development Organisation, or ELDO; https://en.wikipedia.org/wiki/European_Launcher_Development_Organisation

Britain lost interest and withdrew funding and support after the Europa rocket kept failing. On only one occasion was a failure attributed to the British component (the Blue Streak first stage), on one flight, the fuel inside the Blue Streak was sloshing about so much that it destabilised the gyros and the rocket had to be destroyed in flight. https://en.wikipedia.org/wiki/Europa_(rocket)

Britain also had its own indigenous satellite launcher, the Black Arrow; https://en.wikipedia.org/wiki/Black_Arrow although it only ever launched one satellite.

After this, the British realised that space was too expensive and that Britain didn't need a space programme, so stopped building rockets and rocket motors, which it had done so since the end of WW2.

 

[GregP]

Hi Nuuumannn,

How do you state the HS.681 would have outperformed the C-130? I can find an all-up weight but no payload and I have never seen an estimated takeoff or landing distance with a combat payload. Certailly the top speed would have been better, but what about combat support at unimproved strips?

Not saying it would NOT have done so ... I just can't find estimates in a short search of the internet. I assumje you must have a more in-depth analysis of the proposed aircraft somewhere?

If so, could you share some real-world performance numbers with combat payloads and ranges?

It would be nice to know what we didn't get to see ...

 

[nuuumannn]

Greg, I can say that without referencing the figures because it was powered by gas turbines.

For your info though: Four 17,300 lb thrust RR RB-142 Medway engines, span 123 ft 4 in, length 101 ft, height 37 ft 3 in, max t-o weight 171,000 lb. The following figures are what was stipulated in the Operational Requirement, obviously the aircraft would have had to meet and/or exceed these figures: payload 35,000 lb, range STOL radius 1,000 nm, normal radius 2,210 nm, ferry range 4,200 nm. T-o and landing distances; STO to 50 ft 1,610 ft (developed engine figure of 1,455 ft), normal take off to 50 ft 4,050 ft, short landing distance from 50 ft 1,520 ft (developed engine), normal landing distance to 50 ft 2,095 ft. No speed figures provided.

To the same OR Bristol provided the BAC.222, which was a boundary layer control RR Tyne engined short take off variant of the C-130; Lockheed apparently lent its full support. Another idea behind a US/British joint tactical transport was the SC5/45 to AST.364. This was a Short Belfast fuselage fitted with the wings and tailplane of a C-141, again with full Lockheed support.

 

[GregP]

Thanks for the specs! I had not seen them. To be technical, the C-130 is powered by gas turbines, too.

The C-130J hauls 72,000 pounds and has a normal TO distance of 3,127 feet when maxed out. I've never seen a spec at 35,000 pounds of payload. Normal range is 3,262 nm.

So on the surface it looks like the C-130 J hauls more, has a longer normal range, and takes off shorter ... but I assume is slower. The C-130J cruises at 348 knots.

 

[nuuumannn]

Yes Greg; I've worked on Hercs.

o on the surface it looks like the C-130 J hauls more, has a longer normal range, and takes off shorter ... but I assume is slower.

Indeed, but the C-130J emerged at least thirty years after the HS.681 and the figures I provided were a target which the manufacturers were to meet. Here are figures from Armstrong Whitworth Aircraft since 1913: General characteristics

Payload: 35,000 lb (15,900 kg)
Length: 104 ft 2 in (31.75)
Wingspan: 134 ft (40.84)
Height: 37 ft 10 in (11.53 m)
Wing area: 2,250 sq ft (209 m²)
Max. takeoff weight: 181,200 lb (82,360 kg)
Powerplant: 4 × Rolls-Royce Medway turbofans with thrust deflection, 13,790 lb (61.3 kN) each

Performance

Maximum speed: Mach 0.71
Range: 4,801 mi (7,725 km)
Service ceiling: 25,000 ft (7,620 m)

Payload remains the same as the earlier figures, but max t-o weight and range have increased and there are tentative performance figures.

 

[GregP]

I bet they would have made a "stretch" version of it, and the stretch would have been a bit faster. Seems like an interesting project and I like the looks. It looks like a big BAE 146 or a short C-141. Likely it could have been a player. On the surface it seems so and I have no reason to doubt it.

Had it generated any interest, the Handley-Page Herald, an obscure plane if ever there was one, had great performance and SHOULD have been a success, and it got BUILT. It's tough to second guess exactly WHY something that looks good and performs well was passed over. Could be politics, could be price, could be any number of things. More than one has failed due to the original choice of engine, and it usually isn't all that hard to change powerplants unless it is in a limiting category such as the only engine available.

I think I like the HS.681 ... another great "obscure" aircraft except thay didn't build one. We can all probably name from 3 - 8 more that probably SHOULD have made it and didn't.

I wasn't knocking this one earlier, I was asking for specs and looking at comparisons. I'd expect a turboprop transport to out-accelerate a pure jet at least on the ground, probably take off shorter, and be slower. Climb rate could be anywhere depending on power-to-weight or thrust-to-weight.

No disrespect to the proposed HS.681 as it looks like a possible player.

 

[nuuumannn]

{quote]It's tough to second guess exactly WHY something that looks good and performs well was passed over.[/quote]

The Herald was competing directly with the Fokker F-27, which already had a toe in the market when the Herald appeared, not to mention gained an advantage when the Herald prototype crashed. Originally the Herald was powered by piston engines and when HP made the decision to fit Darts, the F-27 had already flown and had attracted sales. The Herald was vigorously marketed and, like you stated, Greg, it was a good aeroplane and although in certain conditions it could outperform the F-27, particularly with its short field performance, the latter won more orders. Politics play a part in its dismal sales record; HP was a pariah within the industry because it refused to amalgamate into either Hawker Siddeley or BAC; in the same market was the HS or formerly Avro 748, which sold well (for a British airframe) and eventually HP went into receivership after HS was awarded work to upgrade Victors for the tanker role, a rather controversial decision considering the Victor was an HP product.

We can all probably name from 3 - 8 more that probably SHOULD have made it and didn't.

Sure can; here's another favourite; the P.1121 Hawker P.1121 - PPRuNe Forums

Another one of considerable interest ito this thread in particular is the Fairey Rotodyne: https://en.wikipedia.org/wiki/Fairey_Rotodyne