Glad to’ve been of help Denys!    The publication I was referring to is +500 pages and describes the development history of RAF armament.    I don’t think that the turret related content will be of much help in any restoration project but it’s an interesting read nonetheless.    Being quite a thick book scanning pages won’t be easy but if you’re interested I can always give it a try.   Just PM me your e-mail address and I’ll see what I can do for you.

If you google pics of Boulton Paul Defiant turrets (the “A” turret if I’m not mistaken you should be able to find some where you can actually see the solenoids).

Cheers,

Walter

Hi again,  the explanatory text in my above post relates to the Solenoid Switches, not the solenoids themselves!

This is the right bit of text :

Q

Firing Solenoids

Type “A” and “B”.  These are very similar and their action is as follows: 

When the coil is energised the plunger is pulled down the magnet pole plate or core, and the ball end of the plunger oscillates the rear sear release lever which in turn raises the tappet.  The tappet will engage the rear sear lever on the gun and in turn the rear sear releasing the breech block.

As there is no return spring in the unit the tappet remains up until the circuit is broken when the rear sear spring on the gun returns all the parts to their normal positions.

It is possible to operate the gun manually if required by lifting one end of the lever, forcing the tappet up and holding it in this position.

UQ

Cheers,

Walter

Hi Denys,   as suggested by powerandpassion these are indeed MG firing solenoids, for the Browning .303 to be precise.   See attached illustrations for more info.

This is the explanatory text that goes with the illustrations :

Q

Type “A” – When the coil is energised the armature and plunger are attracted toward the coil, and the plunger moving causes the contact to bridge two fixed contacts completing the circuit to the firing solenoids.

When the firing switch is opened the magnetic field of the solenoid collapses and the spring returns the plunger and contact, so breaking the circuit.

Type “B” – The action of this type is practically similar to the Type “A” except no armature is incorporated with the plunger and the contact arrangements differ.

UQ

Looks like the ones you have are the type “B”.    

Any chance of sharing a few more pics and giving some dimensions like the diameter of the magnet tube please?

Cheers,

Walter

Fascinating James, thanks for sharing.

Cheers,

Walter

Hi Laurence,

Always good to see Blenheim related questions – my all time favourite aircraft!

In the Blenheim the Wop/AG only had the turret seat to perform both his AG and Wop duties.    The radio installation is located in the back of the fuselage, just behind the gun turret an the poor Wop/AG had to operate the radio (wireless installation in contemporary language  :)) reaching through all the bits and pieces that comprised the turret.   Poor ergonomics to say the least but we know that crew ergonomics were not ranking high on the aircraft designers priority list in those days.

I suppose he could have traversed the turret to the beam position to have somewhat better access to the radio controls but still…    Note the turret only traversed over 180° so it could not be completely “turned around”.

In its initial form the Blenheim’s turret was equipped with the Vickers “K” Gun, also know as the Vickers Gas Operated gun or VGO, a drum fed machine gun with a high rate of fire, similar in appearance to the much older Lewis gun.    In fact, it was possible to fit a Lewis gun to the turret as I have seen in some photos.

Next step was a twin VGO installation but this appears to have been quite rare and so far I’ve only seen a single photo of a Blenheim so equipped.   And after that we go to the final turret version (on the Mk I and Mk IV Blenheims that is, the Mk V sported a completely different mid-upper turret) equipped with twin belt fed Browning .303 guns.

Finally, the Blenheim did have a single .303 Browning in the port wing, aimed and fired by the pilot. 

Feel free to send me a PM for more details.

Cheers,

Walter

Hi Alan, yes, still here, unlike many others, sadly.    I can understand people’s frustration about the new look forum, not happy with it myself but there is so much information to be found in all those past threads and it would be a shame for that to be lost.

Back to the bomb winch – Aerohistorian, if you’re reading this, could you next to a few extra photos perhaps also give some dimensions please?   I’m very curious as to how big this piece of kit actually is!   

TIA & cheers,

Walter