Lancaster Bomb Aimer's blister

[Jonny]

I thought I knew 'my' aeroplanes, BUT ...

 

Photos of most marks of Lancasters I've seen show a horizontal V shaped bracket protruding either side into the bomb-aiimer's blister.  I've seen internal and external photos showing them.  None seem to have anything attached.  What are they for?  Does anyone know?

 

This has puzzled me for ages, but my own limited research has failed to produce an answer!

 

Jonny

 

,

 

Edited May 14, 2017 by Jonny

[stever219]

I've just done a quick web trawl for R5868 at Hendon and she doesn't appear to have them, nor does the nose of DV372 formerly at IWM South Lambeth.  '868 was overhauled between service with 83 Squadron and 467 Squadron RAAF, losing the fuselage side windows in the process but not receiving "your" brackets.  The brackets are, however, clearly visible in many scenes in "The Dam Busters" which used four airframes from the "RT"-serialled batch of Lancasters built late in the war.  I don't think they were there to hang a bomb sight on or to provide foot rests for the front gunner and the emitters for the "Z"-equipment (infra red IFF) were attached directly to the nose blister above the optically flat bomb-aimer's window.  I'm off to see if PA474 or NX611 has them.

 

'474 has them, '611 doesn't.  Further research required.  (Thinks: '611 was sold to the French for maritime reconnaissance work, so was she built with them and they were deemed surplus to requirements for MR work and removed?  '474 had a service life with the RAF (82 Squadron as a PR/survey platform) but was then used as a flying test bed, so how did she keep hers?  The plot thickens.)

 

KB889 at Duxford has an "N"-shaped bracket port side only supporting her bomb sight.

Edited May 14, 2017 by stever219
Additional ramblings

[warhawk]

Hello,

 

I have recently done a bit of research, since I am building a Lanc in 72nd,

and posted nearly the same question at Bomber Command Forum.

 

Although no definitive conclusion was reached, I believe I can make an educated guess, based on photos:

It seems reasonable to connect early (smaller) blister with MK.II bomb-sight, and later, bigger nose blister with the Mk.XIV bomb-sight (which, IMHO, was probably the reason it needed to be enlarged)

If I understood Your question correctly, these "V"-shaped side frames (visible through the nose-bubble) are mountings for the earlier Mk.II bomb-sight...

    

    img source: Weapons and Warfare

 

... and this smaller frame (present only on the left side) is for the Mk.XIV bomb-sight...

    

    img source: Spitfire Spares

 

But, I came across this photo of a restored bird, which seems to show both mounts (??)

My reasoning leads me to believe that this machine got upgraded to a Mk.XIV sight and larger blister at some point, but nobody bothered to remove the old mounting.

    

    img source: Flickr

 

Regards,

Aleksandar

 

[Jonny]

Thanks, Stever 219 and Warhawk.

 

I guess the brackets have something to do with the old / original bomb sight.  I'm always cautious when looking at a museum or restored airframe.  

 

Fantastic photos, Warhawk.  Thanks again for posting.

 

Jonny