wyvernhawk
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which could tell me something about the supersonic buccaneer?
PMN1 said:From Spitfire to Eurofighter by Roy Boot.
'In 1959 serious attempts had been made to sell the NA.39 in its original configuration to the West German Navy'
Does anyone know what the West German Navy thought of the design?
PMN1 said:Later on he also says that there were hopes that the US would adopt the Buccaneer in the same way the USAF adopted the Canberra to make the Martin B-57.
What were the chances of this?
zen said:It would certainly have been possible with Avons, Spey is more a unkown quantity and depends on how much is spent to push out a military variant.
Hammer Birchgrove said:Would it have been possible to have a Buccaneer with RR Speys earlier than 1965?
In another thread, about a DH Sea Vixen with Speys, it was told that the particular aircraft would have flown as "early" as 1960 if RAF had bought it. However, Wikipedia says that the RR Spey wasn't until 1964, but that may be because the Buccaneer Mk 2 first flew then.
Thanks in advance.
I read on Wikipedia that British engineers had worked on what would become turbofans as early the 1930's.TinWing said:Hammer Birchgrove said:Would it have been possible to have a Buccaneer with RR Speys earlier than 1965?
In another thread, about a DH Sea Vixen with Speys, it was told that the particular aircraft would have flown as "early" as 1960 if RAF had bought it. However, Wikipedia says that the RR Spey wasn't first used until 1964, but that may be because the Buccaneer Mk 2 (prototype) first flew then.
Thanks in advance.
The RR Spey came about when the aircraft that became the DeHavilland Trident was scaled down due to a short sighted request by BEA. Consequently, since the Trident was no longer the size of the later 727, it didn't need an engine as large as the JT8D, so the Conway was scaled down to what we know as the Spey.
Needless to say, Rolls Royce was left without a JT8D competitor, and the Trident was very obviously outsold by the 727.
The Spey indeed entered commercial service in 1964, although, arguably, it could have been available somewhat earlier and it is quite obvious that the Conway itself would have been available earlier still.
Development
[edit] Background
In early jet engines the exhaust was much faster and hotter than it had to be for efficient thrust; capturing some of that energy would improve the fuel economy of the engine. The turboprop is an obvious example, which uses a series of additional turbine stages to capture this energy to power a propeller. However there is a tradeoff in propeller efficiency compared to forward speed, so while the turboprops are efficient engines, they are only efficient at speeds of up to 500 mph (800 km/h; 430 kn). This meant there was a sweet spot between the high efficiencies of the turboprop at low speeds and the jet at high speeds that was not being directly addressed. This spot, between about 450 mph (720 km/h; 390 kn) and 700 mph (1,100 km/h; 610 kn), was precisely where the vast majority of commercial jet aircraft spent most of their time.
The basic concept of bypass had been studied from the earliest days of jet engine design. Alan Arnold Griffith had proposed a number of different bypass engine designs as early as the 1930s while he and Haine Constant were trying to get their axial-flow jet engines working at the Royal Aircraft Establishment. Frank Whittle's Power Jets also studied a number of bypass configurations. However, the need to get jet engines into service during the war meant this work had to be put aside in favor of simpler designs with shorter introduction times. The ending of the war changed priorities dramatically, and by 1946 Rolls-Royce agreed that existing engines like the Rolls-Royce Avon were advanced enough that it was time to start work on new concepts like bypass.
Griffith suggested building a purely experimental design using parts of the Avon and another experimental jet engine, the Tweed. In April 1947 a 5,000 pounds-force (22,000 N) design was proposed, but over the next few months it was modified to evolve into a larger 9,250 pounds-force (41,100 N) design in response to a need for a new engine to power the Mk.2 low-level version of the Vickers Valiant bomber. A go-ahead to start construction of this larger design was given in October, under the RB.80 name.
the Conway was scaled down to what we know as the Spey
According to Gunston's 'Rolls-Royce Aero Engines', page 148, the Spey was a scaled-down RB.141 Medway, not Conway.
Engines in the Sapphire/Avon class were specifically rejected early on due to weight and fuel consumption concerns.
At the time, it was thought that a scaled down version of the Gyron was the low risk solution, although it obviously wasn't.
zen said:No they where'nt, as Shorts tender to NA.39 shows and was not rejected due to the choice of engine. Rejected perhaps by Blackburn in their design process for the B.103 perhaps.
zen said:I do wonder why Shorts never proposed a fighter for the RN based on their wing.
Engines in the Sapphire/Avon class were specifically rejected early on due to weight and fuel consumption concerns.
robunos said:the Conway was scaled down to what we know as the Spey
According to Gunston's 'Rolls-Royce Aero Engines', page 148, the Spey was a scaled-down RB.141 Medway, not Conway.
Only five prototype Medways were built, although a lot of parts were used unchanged in the Spey.
cheers,
Robin.
alertken said:HB's Q was: Would it have been possible to have a Buccaneer with RR Speys earlier than 1965? Spey's conception was March,1958, BEAC's DH.121 order. NA.39 first flight was 30/4/58 and Duncan Sandys order for 50 (became 40) was 10/9/58. MoA funding for RB168 (to be Buccaneer S.2's Spey Mk.101) was released in 1959, when payload/range limitations became apparent in Gyron Jr...and RR had little else to do, military or civil. Sloth prior to deployment of Mk.101/Bucc S.2 was a matter of junior priority everywhere, as RR tried for higher volume business (Twin Spey P.1154, all those weird German V/STOL things) and HSAL digested Blackburn. The weapons for Bucc. S.2 were to be WE.177A(N) and Martel, neither of which would be available before 1966.
So: Yes, a couple of years earlier S.2 would have been technically do-able...but there was no champion to fund it.
TinWing said:zen said:It would certainly have been possible with Avons, Spey is more a unkown quantity and depends on how much is spent to push out a military variant.
Engines in the Sapphire/Avon class were specifically rejected early on due to weight and fuel consumption concerns. The entire point of the Buccaneer was to produce an airframe with a balance between range and an acceptable landing weight/approach speed for very marginally sized carriers.
The Gyron Junior was chosen because it best fit the specification, despite marginal thrust. At the time, it was thought that a scaled down version of the Gyron was the low risk solution, although it obviously wasn't.
zen said:Well 800 degrees a second is likely a lethal rotation speed for a human being, and they'd have to put in some sort of limiter. But the Shorts design is a very attractive option if more risky.
That the Gyron Jr was picked for that aircraft is more puzzling for me. Since the engines aren't inside the "body" but on the wings, it must have been relatively easy to give stronger engines more space, may it be RR Avon, Armstrong/Bristol Siddeley Sapphire or even RR Thames or DH Gyron (the full-size version, not sure if the original version had problems like Junior).starviking said:TinWing said:zen said:It would certainly have been possible with Avons, Spey is more a unkown quantity and depends on how much is spent to push out a military variant.
Engines in the Sapphire/Avon class were specifically rejected early on due to weight and fuel consumption concerns. The entire point of the Buccaneer was to produce an airframe with a balance between range and an acceptable landing weight/approach speed for very marginally sized carriers.
The Gyron Junior was chosen because it best fit the specification, despite marginal thrust. At the time, it was thought that a scaled down version of the Gyron was the low risk solution, although it obviously wasn't.
The Gyron Junior's also doomed the Bristol 188 programme, as it hadn't enough time or thrust available to 'soak' at high mach .
overscan said:The Gyron was also the first British engine designed for highly supersonic (Mach 2) flight. Its low pressure ratio was optimised for high speeds. When the Bristol 188 was conceived, Gyron and Gyron Junior were the only engines designed for the high speed flight regime that were likely to be available quickly. It wasn't at all clear then whether existing designs like the Avon, Sapphire etc were suitable for Mach 2+ speeds.
The 188 was seriously overweight due to problems with the steel construction. Progress with it was glacially slow; it was supposed to help research technologies for the F155T fighter but arrived years too late to be of any use. It consumed £20 million (a substantial sum of money at the time) to no great purpose.