Announcement

Collapse
No announcement yet.

Wreckage Of Lancaster ED908 (60-Z)

Collapse
X
Collapse
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
  • Filter
  • Time
  • Show
Clear All
new posts
  • BobKat
    Rank 5 Registered User
    • Nov 2012
    • 886

    Thanks Peter. Looking again at our fabric, I agree that it has much more the appearance of lagging than curtain material, although AP2062A&C does say the curtains were made from canvas! I have found a few pictures which suggest that lagging may well be what we have. Many thanks.

    Your thought for our black tubes seems a much more likely explanation than mine. I wonder whether this could be as you suggest or possibly be from one of the whip aerials on the forward fuselage? I am no electronics expert, but we appear to have a hollow tube which Laurent describes as being a plastic compound, not metal. Would this be a protective covering for an aerial? Laurent says that the tube's external diameter is 25mm (or I inch), and the internal diameter is 17mm (about 11/16ths inch). I have found a few pictures, but they do not provide conclusive evidence that this is what we have. Unless anyone can provide more information, we will probably be unable to pursue this further.

    To complete the photographs of the recent finds, the remaining batches are 115B, D and E. 115B comprises miscellaneous fragments of fuselage, 115D shows pieces of the H2S blister and 115E shows Perspex fragments, probably from the bomb aimer's canopy, and call for no further comment.

    All pictures are now annotated in the Photo-gallery.

    We are now looking at the remains of ammunition found. There may be something to post on this in due course.


    Photo-gallery:
    https://onedrive.live.com/redir?resi...t=folder%2cjpg

    Index to parts found and annotated illustrations:
    https://onedrive.live.com/redir?resi...t=folder%2cjpg

    Attached Files

    Comment

    • BobKat
      Rank 5 Registered User
      • Nov 2012
      • 886

      Peter, not for the first time, you have pointed me in the right direction!

      I think I may have solved the identification of our black plastic tubes (post #1272). The diagram from the Canadian Mk.X Parts List below shows the rear radar installation which has been subject to post-war Canadian modifications. The dipole aerial on the port side is shown without any protective cladding. Its position is highlighted in blue.

      The British MK.III Parts List, AP2062A&C, shows that the beam approach equipment had a shield around the dipole aerial with material specification DTD.315 (see the extract in the illustration below). After a bit of research I discovered that this is an opaque cellulose acetate known as "Black Bexoid" manufactured by BX Plastics Ltd. DTD is the Department for Technical Development.

      This description fits the plastic tubing that has been found. So, it appears that that is what we have – part of the fragmented insulation cladding around the dipole aerial, just as you suggested, Peter. Many thanks once again.


      Photo-gallery:
      https://onedrive.live.com/redir?resi...t=folder%2cjpg

      Index to parts found and annotated illustrations:
      https://onedrive.live.com/redir?resi...t=folder%2cjpg

      Attached Files

      Comment

      • Peter
        Moderator
        • Jan 2000
        • 12518

        Pretty sure thats what you have there Bob.. great job with the diagram
        Cheers,Peter
        "Merlins always drip oil, when they don't....worry!"

        Comment

        • jamesinnewcastl
          Rank 5 Registered User
          • Nov 2010
          • 426

          Hi Bobkat

          I have a particular interest in the SBA system and the arrangement shown is a little unusual. Can you put up the description for items 1 to 5 please?

          Cheers
          James

          Comment

          • BobKat
            Rank 5 Registered User
            • Nov 2012
            • 886

            Hi James, good to hear from you.

            I attach an extract from the Canadian-built Mk.X Lancaster parts list. Peter and I have put a complete version of this together from two different incomplete versions of the list. The original list was dated 1954 and was produced to facilitate the post-war maintenance of the Mk.X Lancaster. The list may have been updated, but it is probably reasonable to assume that this was the configuration in 1954.

            I hope this helps.


            Photo-gallery:
            https://onedrive.live.com/redir?resi...t=folder%2cjpg

            Index to parts found and annotated illustrations:
            https://onedrive.live.com/redir?resi...t=folder%2cjpg

            Attached Files

            Comment

            • jamesinnewcastl
              Rank 5 Registered User
              • Nov 2010
              • 426

              Hi BobKat

              The drawing is a little odd - parts 2 and 3 are exactly the same thing for a start. I assume then that part 4 has 2 stuck on top of it to make the mast longer. But why? There seems to be no reason for it. EDIT - Ah, it could be that parts 2 and 3 have been shown cut to length and the adaptor 4 is just wrapped around the mast. Even so the aerodynamic end part of 1 which is actually intended to take the antenna is now sticking out into space somewhat pointlessly?

              Also part 5 seems to be an insulator, is that a seperate item or does it refer to the whole tube? If it is insulating the wire, then that would make one arm of the dipole antenna shorter than the other - not a good move from a radio point of view. But if the whole antenna is inside an insulating tube then why part 5, which would be an insulator part way along an insulated tube?

              The only thing I can think of is that for some reason part 1 could not be located where it would need to be on the fuselage and that part 5 is just holding the end of the tube/antenna and has another section that meets 1 in an adaptor because it wasn't possible to connect readily with the original end mounting. That seems daft as a 1in insulating tube would do the job nicely. Also the drawing would need to be very out of scale?? Not something that happened back then.

              It all seems very strange but no doubt there were reasons or I'm just not interpreting it correctly.


              Cheers
              James
              Last edited by jamesinnewcastl; 10th September 2019, 13:49.

              Comment

              • BobKat
                Rank 5 Registered User
                • Nov 2012
                • 886

                James,

                It seems that no readers of this thread can help with the dipole mast configuration. I am no expert on radar matters, but I have to say, like you, I couldn't understand why there appeared to be an insulator in one of the dipole arms on the diagram, thereby effectively shortening its length.

                I have searched for photos of the two dipole configurations. I have managed to find a picture on a British Mk.I Lancaster (with no H2S blister) showing the dipole quite clearly to the rear of the mid-upper turret. The diagram for the Canadian Mk.X Lancaster in my earlier post shows the dipole aerial in a different position forward of the H2S blister. Curiously, all the pictures I have found of post-war Mk.X Lancasters show no visible dipole aerial. I attach two pictures for comparison. The centre picture shows a heavy line under the aircraft identification letters with the annotation “LIFT HERE” which is a little odd! The lower one shows a clearer view of the underside of the aircraft.

                If the aerial was sited forward of the H2S blister, it would have to have been fitted quite high on the fuselage to be above the bomb bay doors. It doesn't seem likely, but is it possible that the aerial was located inside the aircraft with only the extended mast protruding at the forward end?


                Photo-gallery:
                https://onedrive.live.com/redir?resi...t=folder%2cjpg

                Index to parts found and annotated illustrations:
                https://onedrive.live.com/redir?resi...t=folder%2cjpg

                Attached Files

                Comment

                • jamesinnewcastl
                  Rank 5 Registered User
                  • Nov 2010
                  • 426

                  Hi Bobkat

                  I'm not too mystified about the antenna arrangement - in order to pick up the two approach beacons it will have been a fixed length, it was the mounting arrangement that was odd. The upper one of your pics is a normal SBA antenna arrangement possibly with a fairing at the front, the middle one isn't SBA, it's too long for a start, I suspect that there is a very long flap hiding some thing - hence the LIFT text. The lower pic could be the second version of that particular antenna from late in the war which was just a single wire.

                  Cheers
                  James

                  Comment

                  • Peter
                    Moderator
                    • Jan 2000
                    • 12518

                    Pretty sure that dipole aerial is well aft of the bombdoors
                    Cheers,Peter
                    "Merlins always drip oil, when they don't....worry!"

                    Comment

                    • BobKat
                      Rank 5 Registered User
                      • Nov 2012
                      • 886

                      Peter, you are right. The plastic cladding (or what AP2062A&C calls a dipole aerial shield), which Laurent has found is from the standard beam approach dipole behind the H2S blister on the Mk.III aircraft.

                      The Mk.X parts list diagram shows a different post-war version of the aerial which is positioned in front of the H2S blister. Having looked at some more photos (with acknowledgements to silverhawkauthor.com), the closest I can get to the diagram is a picture of KB973 with the mid-upper gun turret removed but with the H2S blister still fitted. The rearmost aerial is highlighted in yellow, but it is not exactly as illustrated. The old dipole aerial at the rear has been removed.

                      Another post-war picture of FM212 shows two aerials fitted to the port-side bomb bay door. Again, the rearmost is highlighted in yellow.

                      My efforts to show the position of the cladding around the aerial in post #1282 are therefore misleading as the illustration shows a modified aerial located further forward on the aircraft.


                      Photo-gallery:
                      https://onedrive.live.com/redir?resi...t=folder%2cjpg

                      Index to parts found and annotated illustrations:
                      https://onedrive.live.com/redir?resi...t=folder%2cjpg

                      Attached Files

                      Comment

                      Unconfigured Ad Widget

                      Collapse

                       

                      Working...
                      X