Bristol 173 Helicopter and the Bristol Janus Gas Turbine

GT6Boy

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My late father worked in Raoul Hafner’s Team as part of the Bristol Aeroplane Company Helicopter Design Office. The Bristol 173/191/192 etc. are mentioned in a number of threads here but nothing linking these aircraft to Bristol’s ‘paper engine’, the Janus turbo prop.

I was made aware of this engine, in conversation some 6 or 7 years ago with Reg Austin, who worked very closely under Raoul Hafner throughout this time and indeed until after Westland took over the Bristol Helicopter interests.
IIRC Reg was of the opinion the Janus project(such as it was), was a victim of the Superpriority production initiative, resultant to the Korean War.
It would be fair to say Reg was disappointed with the historical narrative usually applied to the Bristol Helicopters.
Whilst the 173 mk1 & 2 performance did suffer with the (relatively) low power available from the reciprocating Leonides engine, he was not surprised as the Bristol 173 was intended to be a recipient of the Bristol Janus, which with its relatively lightweight and high power output, would have made the 173 a more successful endeavour.

My question here is: can anyone here shed any further detail on the potential matching of this engine to the Bristol 173?

The only mention on this site for the Janus is here:
https://www.secretprojects.co.uk/threads/early-british-gas-turbine-development.1016/page-5#post-157138

Reg did contribute to the email updates on this thread here:
http://www.aviastar.org/helicopters_eng/bristol_belvedere.php


I have copies of the very excellent Blue Envoy Helicopter books and am avidly awaiting publication of The General Staff and the Helicopter in due course. Perhaps research for these books might have dug up further detail on this which may not have been thought relevant to their final publication?
 
All I can add to this is that in all of my rummaging through Kew for Bristol 173 and 191 papers I have never found any reference to the Janus.
Kew does hold a file on the Janus though: AVIA 28/945 https://discovery.nationalarchives.gov.uk/details/r/C4645298

Given the link you have posted to Tartle's post in 2012 and other sources (sadly the Flight archive is down but they have a 1949 article on it) it seems the Janus was circa 1946-49, so right at the very beginning of the 173's development. The scaled 500shp version Tartle mentions the MoS wanted would indeed have been right in the correct power range for the 173. Sadly it seems that the Janus petered out before the 173's development really got underway as the 191 and 192, so its conjecture what impact the engine may of had, certainly it might of saved a lot of wasted effort with the Leonidies Major and trying to keep the weight down.
 
Thank you Hood- much appreciated :)
I recall Reg was absolutely effervescent with enthusiasm for the 173/191 and it was marvellous to hear his thoughts. Less enthusiastic about MoS hamstringing development along the way. ..
It really was a ground breaking time for British aviation.
 
Here's the excerpt from the Flight 1949 volume with the mentions of the Bristol Janus.
Not really many data, sorry ...
 

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Here's the excerpt from the Flight 1949 volume with the mentions of the Bristol Janus.
Not really many data, sorry ...
Thanks Jemiba- it made for scintillating reading: all those engine types in development. Easy to see the potential for duplication in so doing though.
 

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