Bristol Blenheim Mk I L1348

[DaveCromie]

Evening all

I have a question for the assembled cognoscenti regarding the above aircraft. I searched Britmodeller and came up with the following two threads which mention the aircraft in some detail.

PDU Aircraft Thread and Another PDU Aircraft Thread

Between them they contain the only 3 pictures of the aircraft that I can find anywhere on-line. My limited selection of reference books contain several mentions of the aircraft but all have the same 2 pictures in them that make up 66% of the on-line images (2 and 3 below).

(I have taken these images from the above threads but I have no knowledge of whom to credit for their use. If I am in breach of copyright or impinging on someone elses ownership I will delete them - first time posting images on BM)

I am aware that the changes involved in converting a Mk I Blenheim into this particular airframe include:

1. Clipping the wingspan by 3' and re-profiling the wing tips

2. Remove the turret, fill in the gap and smooth the fuselage profile back

3. Remove the lower, front glazing panels and scratchbuild a new nose fairing

4. Fit Rotol Constant Speed propellors (I think I might have to modify the kit ones, slightly rounder tips but what else am I missing?)

5. Build a fairing for the Venturi

Apart from the propellors, my question is what colours and markings did this airframe wear? The above threads come with a variety of suggestions including EDSG/DSG over Sky, EDSG/DSG over Aluminium and DE/DG over Aluminium.

My "interpretation" of the images are that the upper surface is in the standard Temperate Land Scheme of DE/DG, supported by the fact that the serial number is still visible on the rudder. The underside appears to me to be Aluminium based on the apparently high reflectivity of the surface. Both of the underwing serials are in black and appear to be very neat which (IMHO) implies that the original undersurface paint finish hasn't just been stripped off or painted over so is it possible that it is in bare metal?

Markings wise, it looks like standard sized underwing serials, fuselage Roundel and no fin flash. That just leaves the upper wing Roundel, my guess (and it is just a guess based on other Blenheim's of similar vintage) is a standard sized 4 colour roundel, similar to the fuselage one i.e. equal sized colour bands.

Finish wise, I assume (dangerous I know!) that the dark, very straight areas on the wing leading edges and the similar strips at the forward wing roots are some sort of high gloss dope (or similar) over filling/smoothing material and that the paler area at the rear of the wing root is something similar?

I have already put razor saw to plastic and trimmed the wing tips and removed the lower forward glazing so any and all assistance will be very gratefully received!

All the best

Dave Cromie

[Graham Boak]

The RAF did not have aircraft in bare metal for reasons of corrosion - I believe that this has Aluminium undersides but Sky is a distinct possibility. The nose cone may be (as yet) unpainted. The light appearance of the Blue in the roundel, and the dark appearance of the red, explains the low contrast between DG and DE uppersurface colours. This is because of the use of orthochromatic film: the EDSG/DSG combination has much more contrast using this film, although much less than DG/DE on panchromatic.

[rossm]

I would suggest Aluminium for the undersides because of the presence of the underwing serials. It's only an informed guess but I think if the conversion had included repainting with Sky undersides then the serials would have been overpainted. I don't know the exact date but underwing serials were removed around the start of the war. looking at the other threads the photos are dated Sept 1939 so that would tie up.

Ross

[ben_m]

The front-on photo (that I found being sold on eBay a few years ago) shows camera fairings, I think these were mentioned in the threads above.

I think the under surfaces were aluminium paint, and I share the opinion that the upper wing rounds would have been equal 4 colour (type A1).

[Ivor Ramsden]

Are the tailplanes narrower on this aircraft? They look to be in the head-on view but it could just be perspective and I don't have a built model to hand so that I can do a comparison.

[DaveCromie]

Morning all, thank you for your responses.

Graham, I thought that the use of Ortho film might explain the roundel but didn’t know about the effect on DE/DG, thanks for the heads up on that! Score 1 for DE/DG. As to the bare metal being effected by corrosion, that is an excellent point given our somewhat moist climate!

Rossm, your informed guess uses the same logic as mine, so score 1 for painted aluminium undersides.

Ben, the threads do mention camera fairings but I can only see the two blisters that are seen on the bomb bay of all Blenheim undersides. Can you elaborate on this?

Ivor, I see what you mean in the head on image, I hadn’t noticed it before! However, it looks to me though it may be an effect of perspective rather than metal mangling. The wing tips were shortened at a convenient panel line (assuming they were both shortened by 18”!) and the squared tips faired in whereas the tail planes seem to have retained their distinct curvature. I think I’ll leave mine as they are….for now

Regards

Dave Cromie

[SleeperService]

Showing that old threads never become useless. My good friend Richard has found two more images to share.

 

 

This seems to prove that the propellers were fitted BEFORE the metal nose piece or the teardrop windows were fitted. Possibly one item changed then tested before the next bit?

 

 

Looking carefully at the 'bulges' in the top photo and comparing to the head on view I think there are two rectangular windows running fore/aft on each outer edge of the belly. The lower photo shows an abrupt change in underside finish forward of the wing trailing edge. With such a neat job of plating the turret opening I suggest that the bomb bay area was stripped and a new belly piece with the windows fitted. What think you?

 

Final question has anybody any suggestions for suitable propellers for a 1/48 build?

[woody37]

I think that change in underside colour is just the lowered flap

 

[Graham Boak]

I thought that, but there's also a little step-up in the demarcation aft of that.

[dogsbody]

It may not be that easy to make a regular Blenheim prop look like that Rotol unit.

 

 

 

 

Chris

[mhaselden]

Interesting that the first image in Post #7 shows the aircraft with standard black undersides.  Perhaps it was a case of the underside paint being stripped back to the natural metal. 

[SleeperService]

On 9/18/2019 at 6:55 PM, woody37 said:

I think that change in underside colour is just the lowered flap

 

 

On 9/18/2019 at 7:27 PM, Graham Boak said:

I thought that, but there's also a little step-up in the demarcation aft of that.

I kept quiet just in case it was my fevered imagination at work. However if those are rectangular windows on the underside, replating as with the rear turret would make sense.

18 minutes ago, mhaselden said:

Interesting that the first image in Post #7 shows the aircraft with standard black undersides.  Perhaps it was a case of the underside paint being stripped back to the natural metal. 

L1348 has certainly got a tale to tell. Tomorrow we'll be going through Richard's vast pile of Blenheim books to see what turns up.

 

@dogsbody They are rather tricky things aren't they? Sometimes finding an answer just leads to two or more further questions....

 

 

[dogsbody]

3 hours ago, SleeperService said:

 

I kept quiet just in case it was my fevered imagination at work. However if those are rectangular windows on the underside, replating as with the rear turret would make sense.

L1348 has certainly got a tale to tell. Tomorrow we'll be going through Richard's vast pile of Blenheim books to see what turns up.

 

@dogsbody They are rather tricky things aren't they? Sometimes finding an answer just leads to two or more further questions....

 

 

 

The only other aircraft I can think of with a prop like that is this Miles Master.

 

 

 

Chris

[ben_m]

Just posting an update:

 

there are scans at higher resolution of most of the photos shown above at Air-Britain (all from same time, after full mods):

https://abpic.co.uk/pictures/registration/L1348

 

I think these solve the mystery of the underside camera location(s): the bulges on either side of the belly that I interpretted as camera window fairings are just doped-over protrusions (like the left side of the cockpit where the venturi tube for the instruments is)- and I think the cameras were in fact mounted in the nose where a big new window is installed on the right side (see this brightened image):

 

[V Line]

The props are Rotol internal cylinder types of 10ft 9ins diameter with magnesium blades. The diameter is the same as the dH prop.

 

There were two different blade drawings and I do not know which is fitted in this photo. 

 

The photo of the Miles Master (above) also has a Rotol internal cylinder prop although the blades are of wood.