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-   -   Supersonic Harrier (https://www.pprune.org/flight-testing/486335-supersonic-harrier.html)

GR3a 25th May 2012 11:56

Supersonic Harrier
 
Was the demise of this project technical or political?

Genghis the Engineer 25th May 2012 15:10

I thought that the SHAR would do around 1.2 clean?

G

Fitter2 25th May 2012 16:30

I believe the OP is referring to the P1154, under construction in 1965.

The Labour Government (not implying that another colour of politician would have been any better) could afford one out of Concorde, TSR2 and P1154, and cancelling Concorde was impossible given the treaty with France.

GR3a 25th May 2012 17:50

I'm sorry my initial post was pretty lazy as distracted with work.

Yes I was referring to the P1154.

I was reading through this site as a point of reference

[URL="http://www.harrier.org.uk/history/history_p1154.htm"]http://www.harrier.org.uk/history/history_p1154.htm[

I guess asking if it was political or technological question isn't entirely asking it correctly.

With this project cancelled yet the continuation of the subsonic version I had wondered beyond the technological challenge of V/STOL how/why achieving a high Mach number was not pursued. Being simplistic about it, if you are going to have a jump jet why not have one that would also do Mach 2?

Milo Minderbinder 25th May 2012 19:12

GR3a
the history books suggest that the spec of the RAF and RN requirements became so diverse that one aircraft couldn't do both roles, so the project died as developing both would have been too expensive

However read John Farley's posts on this page
Maybe there was a practical engineering problem as well
http://www.pprune.org/military-aircr...ml#post7144134

sandiego89 29th May 2012 13:06

Supersonic V/STOL is possible, but not very practical. Any jet design is a comromise, and V/STOL even much more so. So why it might seem logical to "want" Mach 2 in your design, getting there is quite tough and will come at a cost. The P1154 was to have a complex engine with plenum chamber burning (basically afterburners on the "cold" front nozzles). Other higher speed V/STOL designs were to use multiple engines, or lift engines and other complex arrangements. All of these lead to extra weight, compexity, cost and high fuel consumption. When it comes down to it, most have concluded that they do no "need" MACH 2, especially with the costs/compromises it brings, and you do not need MACH 2 for close air support. If you really need a MACH 2 interceptor, better to have a conventional (non-V/STOL) design.

As proven with the Harrier, the best arrangement for a V/STOL aircraft to date has been a single engine design with a large, vectored, turbofan engine. The size of the fan, the thrust coming out of the engine (a huge volume but at a relatively low velocity) and the intakes limit the top speed of the harrier family.

GR3a 31st May 2012 13:31

I can seereally only one other design study that attempted to mate supersonic and VTOLcapability, the Rockwell XFV-12.

Given itcame some time after the abandonment of the P1154 these barriers were seen assomething that could have been over come?

Harley Quinn 2nd Jun 2012 17:47

The XFV-12 didn't have sufficient vertical thrust to justify the V in VTOL. The EWR VJ 101 achieved Mach 1.04, but like the Mirage IIIV (which achieved M1.3) needed specialised lift engines.
Strangely it seems the Europeans had a better hit rate than the US, they just didn't have the ability to go into series production of the prototypes that actually flew, with one spectacular exception.

GR3a 9th Jun 2012 09:51

Given the pretty large time gaps in all these projects, successful or otherwise, it is incredible the differences in layouts to achieve the same end point and actually the successful harrier design seems not to have been copied.

Is it a reflection upon constant learning or a simple stubborn - ness and desire to be different?

GR3a 9th Jun 2012 16:57

Thank you for that link it pretty much covers my initial question.

Is the conclusion to be drawn from it all that its taken pretty much 50 years to make a production reality of an aircraft that was conceived with the P1154?

Pugilistic Animus 8th Jul 2012 17:36

pboyall
I remember that thread loved it :ok:


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