Bristol 173 service trial dates

GT6Boy

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Good afternoon folks- I'm trying to establish when and where, the Bristol 173 carried out service trials; might anyone be able to assist?
It is well documented in the written form and online(uh oh. ..) that the 173 mk1 under the Service registration XH379 carried out trials on HMS Eagle in late November 1953.
It is either implied or mentioned as fact that 'the 173' then carried out further trials with the RN and indeed, trials with the RAF.
I cannot however, find detail of the kind evident from the HMS Eagle trials, that either the 2nd RN or RAF trials actually took place?

Are the 2nd RN and RAF trials apocryphal?

For those interested- I've put together my understanding of a Spotters Guide to 173 timeline identification. I've only attempted this as a lot of the on-line and even written sources are inaccurate regarding dating the aircraft depicted :)

The 173 mk1 initial flights were made without doors etc. and no oleo balance pipe hoops above the unfaired undercarriage sponson struts.
The 173 mk2 was never fitted with undercarriage sponson struts.
Both the 173 mk1 (G-ALBN/XF785) and the 173 mk2 (G-AMJI/XH379) were initially displayed, post 1st flights, in painted form:
The 173 mk1 in white over silver with Blue cheat line.
The 173 mk2 in the 1st of 2 BEA schemes(with winglets briefly)
Thereafter, for a period of time, they both operated in natural metal finish, with service markings and there are photos of the 2 in-flight together( a date would be great to know).
I presume it was at this stage that one or other of the airframes would have been involved in the trials under question. ..
The 173 mk2 was fitted with the new 4 bladed rotors on 11/02/55, still in natural finish.
The 173 mk2 was painted in a different BEA paint scheme for trials with the airline in July 1956- seemingly initially with the conventional Dihedral tailplane.
The 173 mk2 crashed at Filton families day on September 16th 1956.
The 173 mk1 then received the trial flat tailplane at that time fitted to the crashed 173 mk2 and was then painted in a new scheme of white over silver with red cheat line, by the end of September 1956. The same scheme it still wears.

There are many examples of photographs being misrepresented- the 173 mk2 taken from above is a Bristol Aeroplane Official photograph that is printed to the rear: Bristol 192 Belvedere!
The Aeroplane illustrative cover shows the 173 mk2 overflying HMS Eagle, when in fact it was the 173 mk1 which carried out the November 1953 trials on HMS Eagle.
XH379, Bristol 173 Mk.2, RAF Mks. 2 JAN.56 smallest.jpg
 

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The trials using G-ALBN (serialled as XF785) aboard HMS Eagle took place on Monday 9th to Friday13th November 1953 (did not actually land on the carrier until 08:30 Tuesday 10th, Monday was spent flying from Filton to Gosport).

The pilot was Bristol's Mr C. T. D. Hosegood with three crewmen; Langfield, Coles and Francombe. A team from Britsol including Hafner, Turner and Howarth were flown aboard by an S.55 and later further Bristol team arrived; Sibley, Prater and Ashman. So the trials were largely a company affair to get design data for the Type 191 programme rather than an official RN evaluation. There was a party from the RAE present too, they photographed the landings to measure the vertical velocities at touchdown.

Photographs during the trials show a natural metal finish. An RAF roundel was added aft plus the serial number.

I don't have any other details of further flight tests with the RN. It seems the majority of the test points were achieved during those four days (except for the full deck motion landing assessment as HMS Eagle was so steady she didn't roll that much in moderate seas), so its not likely that further shipboard trials would have been necessary.

That is a handy guide, properly identifying each prototype is sometimes tricky.
 
Bristol Type 173 Mk.1
The diameter of the propeller, m 14.81
Length, m 23.83
Height, m 5.26
Weight, kg
Empty 3537
Maximum takeoff 4808
Engine type 2 PD Alvis Leonides 73
Power, hp 2 x 550
Cruise speed, km/h 137
Practical range, km 450
Speed, m/min 360
Service ceiling, m 5975
Static ceiling, m
Crew, 2
Payload: up to 14 passengers
http://www.airwar.ru/enc/ch/b173.html
http://aviadejavu.ru/Site/Crafts/Craft20764.htm
 

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The pilot was Bristol's Mr C. T. D. Hosegood with three crewmen; Langfield, Coles and Francombe. A team from Britsol including Hafner, Turner and Howarth were flown aboard by an S.55 and later further Bristol team arrived; Sibley, Prater and Ashman. So the trials were largely a company affair to get design data for the Type 191 programme rather than an official RN evaluation.



I don't have any other details of further flight tests with the RN.

That is a handy guide, properly identifying each prototype is sometimes tricky.
My father used to play skittles with Mr Sibley! :)

Edit- erroneous question removed.

I wonder if the Bristol Collection have the Logbook for G-ALBN- that would make for interesting reading. I will enquire :)

Yes- identifying them can be a trap for the unwary.
 
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Great photos thanks.
The 2 airfield shots are both Filton.
The Bristol car image is the Mk1 in its initial paint scheme(white over silver & blue cheat line).
The 2nd airfield shot is the same aircraft in its 2nd and final paint scheme (white over silver & ref cheat line. This can be dated to post-end of September 1956 when the flat tail plane was fitted, and its grounding in 1959-ish :)
 
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there are photos of the 2 in-flight together( a date would be great to know).
I have a photograph of the two flying together (XF785 in foreground with open doors) dated 27 August 1954.

Mk.1 G-ALBN XF785 was assessed by A&AEE Boscombe Down from December 1954 to July 1955. It was assessed again in the summer of 1958 when fitted with the ‘H’ tail from the damaged Mk.2 and four blade heads.
 
there are photos of the 2 in-flight together( a date would be great to know).
I have a photograph of the two flying together (XF785 in foreground with open doors) dated 27 August 1954.

Mk.1 G-ALBN XF785 was assessed by A&AEE Boscombe Down from December 1954 to July 1955. It was assessed again in the summer of 1958 when fitted with the ‘H’ tail from the damaged Mk.2 and four blade heads.
Is that an 'official' press release type photograph do you know? Like this image perhaps.
 

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Is that an 'official' press release type photograph do you know?
Hi, it would be a copy of a Bristol photograph, not the same as the one you show but probably taken a minute or two before or after. It is only a hand written date, unfortunately nothing official, but I believe it to be correct.
 

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