Mosquito Highball turbine details

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snapdragon

Airman
20
12
Jun 28, 2013
Hi Guys,

I am helping out my old school out and others with a follow on from my hugely successful Operation Chastise project and display which saw my HK 1/32 Dambusters Lancasters (1 suspended at a scale 60ft with two light circles painted on dark paper to represent the water, and one on its legs waiting to go.

I have now turned my attention to the Highball version and thanks to the De Haviland museum and various sources on the net I have managed to figure out the highball cradles etc, but the air turbine is a bit problematic. I have diagrams that show elements of the turbine setup but not how the turbine shaft fits all the way through to the rotating gears for the bombs.

Also I am having difficulty understanding where the air goes after turning the turbine. It is clear from one drawing of the intake on the starboard side that goes each side into the turbine around the bay support but I don't understand the long downward tube's function that seems to fix on the inner wall of the bomb shroud, or where the turbine air vents after passing through.
Highball AP 1.jpg


Highball AP 2.jpg


Highball AP 3.jpg

This is what I have to work with.

Does anyone have a more fuller set of drawings etc they can share or knowledge of just how I can understand and build this.

Aftermarket doesn't seem to have the detail I am looking for and HK's 1/32 Mossie is patiently waiting in its box. Also, if someone has a colour scheme for 618 Squadron and test aircraft that would be very useful too.

Many thanks for any useful information
 
Hi Guys,

I am helping out my old school out and others with a follow on from my hugely successful Operation Chastise project and display which saw my HK 1/32 Dambusters Lancasters (1 suspended at a scale 60ft with two light circles painted on dark paper to represent the water, and one on its legs waiting to go.

I have now turned my attention to the Highball version and thanks to the De Haviland museum and various sources on the net I have managed to figure out the highball cradles etc, but the air turbine is a bit problematic. I have diagrams that show elements of the turbine setup but not how the turbine shaft fits all the way through to the rotating gears for the bombs.

Also I am having difficulty understanding where the air goes after turning the turbine. It is clear from one drawing of the intake on the starboard side that goes each side into the turbine around the bay support but I don't understand the long downward tube's function that seems to fix on the inner wall of the bomb shroud, or where the turbine air vents after passing through.View attachment 844364

View attachment 844367

View attachment 844368
This is what I have to work with.

Does anyone have a more fuller set of drawings etc they can share or knowledge of just how I can understand and build this.

Aftermarket doesn't seem to have the detail I am looking for and HK's 1/32 Mossie is patiently waiting in its box. Also, if someone has a colour scheme for 618 Squadron and test aircraft that would be very useful too.

Many thanks for any useful information
The tube is the air inlet to drive the turbine in the air-driven versions. Looks like three different versions. One hydraulic drive and two by air turbine. Speed in the hydraulic system will be controlled in the hyd system itself. In the middle arrangement the speed of the turbine (Highballs) is controlled by extending or retracting the air inlet. The bottom arrangement is controlled by shutters on the turbine outlet operated by a governor set to the desired speed. The amount of air entering is also controlled by the two-position shutter which probably allows for the system to start at lower load / speed. Exhaust from the turbines is just vented to atmosphere through the bomb-bay

It looks like you need to buy another two kits!
 
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Hi,
I only have limited info about this but, there is a useful article about Highball in the Key Aero online forum.
Just looking at your limited illustrations, I also see THREE different arrangements. The Key Aero article says that the system(s) were difficult in development and were redesigned.
The first illustration, Fig 6, shows a hydraulic motor drive to the gearbox.
The second, Fig 7, shows a similar gearbox and drive pulleys, but with an air turbine fed with ram air from a fixed scoop on the Starboard side.
The third, Fig 9, shows a similar gearbox and drive (but with a jockey pulley), and different air turbine fed with ram air from an extendable scoop on the Port side.

Eng
 
Thanks for the replies, guys. I think the hydraulic one was after the war, intended for the sea Mosquito and Hornet. It's the other two that I am most interested in. The first one with the extendable scoop could be the test phase one while the fixed scoop could be the operational one that was fitted to the 618 Sqn Highball Mossies.

I was chatting to one of my friends in the modelling industry and mentioned my project and the headache it is causing me. They asked me to send them all my research. Building these systems is going to be fun!
 
Hi everyone , Just off the top of my head at the moment . The Highball Mossie [ 618 Sqdn ] Mosquito BMkIV - 4 blade props , 6 stack exhausts , standard " green / grey " topside pattern , under-surface color is P.R. blue or possibly Azure Blue , Blue and white [ Australian ] type roundels [ not SEAC ] and there is a wall [ armour ? ] blocking off the cockpit to the defunct bomb aimers position [ vis Mossie FbVI armour bulkhead ] . Aircraft had an individual code letter , but no Squadron codes evident .
 
Hi everyone , Just off the top of my head at the moment . The Highball Mossie [ 618 Sqdn ] Mosquito BMkIV - 4 blade props , 6 stack exhausts , standard " green / grey " topside pattern , under-surface color is P.R. blue or possibly Azure Blue , Blue and white [ Australian ] type roundels [ not SEAC ] and there is a wall [ armour ? ] blocking off the cockpit to the defunct bomb aimers position [ vis Mossie FbVI armour bulkhead ] . Aircraft had an individual code letter , but no Squadron codes evident .
Level of modification depends on what period we are talking about, and may explain the differing turbine layouts in part.

Operation Servant spec aircraft in 1943; OR
Operation Oxtail spec aircraft in late 1944 / 1945

Most, but not all, of the former were rebuilt by Marshall of Cambridge for the latter with some extra airframes added to the mix.

Long discussion over on Britmodeller a few years ago as to their colour scheme, markings (and other things) which varied over time. PRU blue undersides were ruled out.

And for the Oxtail aircraft, you have missed the most important feature. The arrester hook and fuselage strengthening.
 
Sorry , it was just a quick reply [ " off the top of my head " ] and hopefully markings wise it was a starting point for snapdragon . That's why I mentioned both choices of under-surface colors [ and completely forgot about RAAF Sky Blue being the main huge contender ] .The arrestor hook is visible in respective pictures , and I didn't consider mentioning it . The Britmodeller site is a great site for this topic . But as snapdragon is finding out , the running gear could prove very difficult to work out . I was lucky enough to visit the Narromine Aviation Museum many - many years ago and they had a 1/32 scale Highball Mosquito model [ Revell base kit - H.K. didn't exist ] and a lot of info [ not just Highball ] as Narromine airport actually has a largely forgotten important history in Australian Aviation . One more thing I noticed a while back [ possibly on the Britmodeller site ] was 1 or 2 photos taken at Narromine of a Highball Mosquito with a bomb in place [ taken from front looking back ] . The quality wasn't great but interestingly the bomb seemed to be less spherical than all the other Highball bombs photos we see . Snapdragon - could we see some pictures of your Dambuster Lanc set up , it sounds great .
 
OK , I just went back through the Britmodeller site [ thanks for jogging my memory EwenS ] and found the 2 pictures I mentioned . They are on the Key Aero link and just having a very - very close look at the photos -- I am leaning more towards the bomb bay being empty and the " bomb " is actually the rear wall of the bomb bay ! [ and not a flattened Highball ! ] As I said they are not the best quality photos [ but are great to see ] and the caption reading as a bomb being on board could actually be wrong . The angle of the picture doesn't show any bomb bay interior detail that would be helpful though .
 

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