Mosquito Type F Transmitter Switch - What is it?

[Charly_Owl]

Hi folks,

I have yet another question regarding the Mosquito. There's a "Type F" transmitter power switch next to the navigator seat. When set to ON (AFT), there is a warning light that keeps blinking, but I couldn't find any information about what this switch does exactly. Some speculate that it's some sort of IFF system, while others say it transmits a constant signal that can be homed on by other planes. So far, I couldn't find any information about what this switch is and what it does. Can the Eagle Dynamics team or any Mosquito expert give us an explanation for what this strange "Type F" switch is?

[Rockrend]

Hi Chuck,

Ive found this on a kit modellers forum. The discussion explains what it could be and the associated hardware. https://rnzaf.proboards.com/post/275572/thread

BTW…thanks for all of your work, it is an excellent resource. 

Edited October 15, 2021 by Rockrend

[Bozon]

4 hours ago, Charly_Owl said:

Hi folks,

I have yet another question regarding the Mosquito. There's a "Type F" transmitter power switch next to the navigator seat. When set to ON (AFT), there is a warning light that keeps blinking, but I couldn't find any information about what this switch does exactly. Some speculate that it's some sort of IFF system, while others say it transmits a constant signal that can be homed on by other planes. So far, I couldn't find any information about what this switch is and what it does. Can the Eagle Dynamics team or any Mosquito expert give us an explanation for what this strange "Type F" switch is?

This switch is obviously used to turn on the little yellow light.

[Reflected]

It's an IR lamp for IFF

 

Quote

FIGHTER COMMAND OPERATIONAL INSTRUCTION NO.4A/1945
OPERATIONAL USE OF TYPE 'F' AND TYPE 'Z' EQUIPMENT
BY NIGHT FIGHTER SQUADRONS OF FIGHTER COMMAND

INFORMATION

1.    Type 'F' equipment consists of two separate installations, a simple lamp fitted in the tail of the

aircraft which transmits an infra-red beam, and a specially designed telescope fitted in the pilot's cockpit.      

 It is now fitted to all Night Fighter aircraft of this Command, and a considerable number of aircraft of other

Commands, as an additional aid for air to air identification at night.

2.    Type  'Z' equipment consists of a similar lamp which also transmits an infra-red beam, but which is fitted

in the leading edge of the wing of the aircraft.      This equipment is designed to identify the aircraft fitted

with it to an air-gunner in Bomber aircraft equipped with A.G.L.T. and Type 'Z' Receiver.

3.    Type  'F' and Type 'Z' equipment will be used in all Night Fighter aircraft of Fighter Command operating

over the Continent as well as this Country.

4.    Signals from Type  'F'  transmissions will normally be received up to a range of 1.5 to 2 miles,   the

cone of reception being 12 1/2° either side of this line of flight of the aircraft.      Type 'Z' transmissions

have a similar performance to that of Type 'F'.

 

[Reflected]

Let me know if anyone finds the lamp itself, because I can't.

[Holbeach]

The IR source and lamp is in the tail cone, but I believe you need a detector in the sight to see it.

 

..

Edited October 15, 2021 by Holbeach

[Reflected]

Just now, Holbeach said:

The IR source and lamp is in the tail cone.

 

..

I only see 1 lamp and that is the tail light. Can you please post a screenshot?

[Holbeach]

It would be directly below the nav light. If that's the nav light, then no we havn't got it.

There should also be a IR detector telescope in the cockpit, maybe NF only.

Second extract:

"I am directed to refer to your communication dated 29th January, 1945, reference 452.05 regarding the above

subject.  The following is the fitting programme for British aircraft with details of the progress which has been

made:-

(a) Type 'F'

(i) The programme is to fit all Mosquito night fighter squadrons in Bomber Command, Fighter Command and 2nd T.A.F.

with Receivers and Transmitters, and this programme has now been completed.

(ii) It is also intended to fit all Bomber Command aircraft and the Mitchell and Mosquito bomber squadrons of 2nd

T.A.F. with Transmitters.  The fitting of Bomber Command aircraft has not yet started as the necessary

modification sets are not yet available.  The modification sets for some of the Mitchells of 2nd T.A.F. are now

being issued."

Looking at NFII HJ 711 in Lincolnshire, which does have the transmitter fitted, then we don't have it and Bozon answer is probably correct.

33 is the lamp bracket.

There should also be a flasher coder in the cockpit.

We don't have it.

 

..

 

 

 

Edited October 16, 2021 by Holbeach

[Holbeach]

Here's another picture of the IR source, (W), if you don't already have it.