Mosquito "Resin Lamps"

[zotbox]

Cliffnemo:
thank you for your quick response, it was your detailled drawing of the instrument panel on your thread that made me think that you would remember such a system if it existed.

The thread that started my research in this area is over on Britmodeller; Post 11 contains pictures of the lamps in question on the trailing edge of a Mosquito aircraft in the De havilland museum. perhaps you might take a look and see if they ring any bells.

Mosquito Resin or IR Lights - Britmodeller.com

thanks again,

Zotbox

[stepwilk]

The IR technology that "first appeared" during the Vietnam War was an attempt to use IR as guidance for weapons--glideable bombs and the like. It would come to fruition much later, in the Gulf Wars, but Vietnam saw the first baby steps.

One of the types that carried this primitive stuff was the Schweizer sailplane-based Quietplanes that flew near-silently--actually you could hear them but they sounded more like a large flock of birds than an airplane--at night, but it was never really employed for its design purpose.

[forget]

I've been trying to figure out what possible acronyms could come from RESIN. It seems that, before IFF Transponders, an IFF system used two separate units. A RESponsor (?) and an INterrogator.

'Could be onto something Holmes'.

US Radar: Operational Characteristics of Radar Classified by Tactical Application [FTP 217]

[Bushfiva]

The use of blue lights is interesting. The eye can focus on red very well, almost as well on green, but not very well on blue: you can tell a blue light is there, but typically you can't focus on it in the dark. Does blue have a meaning in aeronautics, akin to the colours for port and starboard? If not, why was blue used? Solely because it's readily distinguished from red and green?

[deltayankee]

I've been trying to figure out what possible acronyms could come from RESIN. It seems that, before IFF Transponders, an IFF system used two separate units. A RESponsor (?) and an INterrogator.

Good guess, but in those days codewords were usually selected at random from a list and codewords that might hint at their meaning were discouraged.

[Aerials]

Here's my guess at the reason for blue lights. At the height that the bomber streams operated, the lights would have appeared to be quite small and perhaps indistinguishable from the background stars.

Aerials

[handsfree]

Reference to small lavender-coloured resin lights

Description of build up to Sicily landing in WWII mentions the resin lamp

HyperWar: US Army in WWII: Sicily and the Surrender of Italy [Chapter 5]

Relevant bit is:-

Arriving in North Africa in April 1943, the 52d Troop Carrier Wing was considered fully qualified in dropping parachutists and towing gliders, but only on daylight missions. Accordingly, the troop carrier units concentrated on night formation and navigational flying, using both normal navigation lights and, later, as proficiency increased, small and lavender-colored resin lights, which would be the only aids available during the Sicily operation. But no real effort was made by the wing to check the location of pinpoint drop zones at night. A night joint training program with airborne troops and carriers fared poorly

[forget]

deltayankee;

Good guess, but in those days codewords were usually selected at random from a list and codewords that might hint at their meaning were discouraged.

Not entirely correct. In fact, entirely wrong. Rainbow codes were not introduced until after the war so RESponsor (?) and INterrogator may well be valid.

The Rainbow Codes were a series of code names used to disguise the nature of various British military research projects from after the Second World War until 1958 when they were replaced by an alphanumeric code system. The Ministry of Supply (MoS) initiated the idea since during the war some German secret projects could be inferred from their code names; for example, that a radio navigation device "Wotan" used a single beam because the Germanic god Wotan was one-eyed.

Wiki

[deltayankee]

The Rainbow Codes were...

Maybe practice varied according to department because RV Jones mentions the choice of meaningless codenames in his wartime memoirs.

Our friend The Wikipedia also says:

In the Second World War, code names common to the Allies referring to nations, cities, geographical features, military units, military operations, diplomatic meetings, places, and individual persons were agreed upon adapting pre-war naming procedures in use by the governments concerned. Random lists of code names were issued to users in alphabetical blocks of ten words and were selected as required. Capricious selection from the available allocation could result in clever meanings and result in an aptronym or backronym although policy was to select words that had no obviously deducible connection with what they were supposed to be concealing.

It is also possible, though, that the name resin just referred to the material used for some lamps.

[HighTow]

Just to add something on the matter of the use of IR in wartime.

A friend of mine had a few original copies of proposal documents liberated from the drawing office of G.A.L post war and one was for an assault glider. What was noticeable was that the specification specifically detailed that the instruments were to use IR reflective markings to be illuminated by and IR lamp in the cockpit and the cockpit interior painted matt black.

My interpretation is that this was to allow them to fly with the cockpit in total darkness as no visible lights shone but that the pilots would wear some sort of goggles that allowed them to read the dials. One wonders if this would also allowed them to see IR emitting formation lights fitted to the tug as well.

[cliffnemo]

Resin lamps

I had a long phone call with my oppo, he of the Halifax rebuild, and he says he never heard of resin lamps. He is very knowledgeable, and told me that when he was in Italy, he designed an I.R lamp which would transmit a signal via aldis lamp, that was not visible to the human eye, but could be read by a two valve receiver some distance away . A thin sheet of ebonite ? was placed in front of the Aldis lamp, which then only emitted infra red, also known as black light, and was invisible. It was very successful, but when the C.O found out he was told to forget it, and get on with the work he was paid for.

Sorry CLIFFNEMO

[Blacksheep]

I was trained as an aircraft electrician in the early sixties on 1950s aircraft. An aircraft electrician would be required to know about any lamp on the aircraft, secret or not or else how would we test and relamp them? Yet I never encountered an Infra-Red lamp - though we did have Ultra-Violet cockpit lamps. These used a normal filament lamp behind a "U/V" filter and the lamps activated the instrument paint. The result was a dark cockpit with all visible lights turned off and only the instrument markings visible. Naturally, these lamps were referred to as "You-Vees".

The lights on the tail and wingtips were mostly navigation lights. When I worked on PA474 it had rear facing lights on the wingtips and these were referenced as "Formation Lights" They were dimmer than navigation lights and were on a separate circuit. We electricians understood them to be intended for night-time taxying and in the circuit; though for glider towing they might be useful for helping the glider pilot remain in position directly behind and slightly below the tug. The rear facing lamps on the deHavilland Heritage Centre Mossies appear to be these same formation lights.

[stevef]

A couple of UK-registered Dakotas I've worked on had (non-functioning & painted-over) blue formation lamps on the wings. From fading memory, they were about three inches in diameter and possibly two per side. I imagine these would be evidence of their RAF service days.

[Chugalug2]

Well, my old Varsity and Hastings Pilots Notes confirm that both were fitted with resin lights, and Identification Lights. I mention the latter merely to confess that I had no idea of their use either, other than that implicit in their title. The Varsity Notes merely mention where the RL light switch is. The Hastings Notes are more forthcoming; "The three resin lights in each wing tip are controlled by an on/off master switch and a GREEN-CLEAR-RED selector switch.". BTW the Downward ID Lights para says; " The three downward identification lights in the fuselage nose are controlled by a switch on the coaming panel. Red, green or amber can be selected and, by pushing up the small lever on the morsing switchbox, the selected lamp can be used for morsing". It infers that the "colour of the day" and the associated code word could thus be displayed, but such techniques were long abandoned by my time (>1962) together with whatever one used to do with resin lights. Regarding the name, many components were then known by the manufacturers tradename (ie Graviner switches, Decca navigator, etc), though I've never heard of such a company as "Resin".
PS Have just dug out my old AP129 vol2. Under Night Formation it reads; "If dim/bright navigation lights are fitted, the dim setting should be used but,when available, resin lights are much better". So that appears to define their use and their properties, ie they were very dim and thus did not dazzle when in formation at night. It appears that the colours were somewhat variable from the blue of Mossies through to "traffic lights" on Hastings! Could the name be a reference to the dimness of a light shining through resin?
PPS Or how about simply REStricted INtensity lights?

[zotbox]

Thanks for all the replies Gents, I think that we are actually getting somewhere close to the function of these lights, especially with your quote from the AP for the Varsity Mr Chugalug!

Thanks to Clliffnemo for contacting his oppo as well!

[zotbox]

National Archives result?

Gents,

I have found the following tantalising reference in the National Archive catalogue:

AVIA 15/1436 "Aircraft; General- ID and Recognition (code 5/5); Air to air recognition lights, Resin system"

Anyone off to Kew soon?

I have applied fior an estimate to copy this document. I will off course let you know how I get on.

Regards,

Zotbox

[HighTow]

Try the TNA Digital Express service - 10 images from the file sent in JPEG format for £8.50 usually delivered within 24 hrs.

[sooty655]

TNA

Originally Posted by zotbox

Anyone off to Kew soon?

I will be spending several days at TNA Kew in May. If you haven't had a result before that, pm me and I will have a look at the file.

Sooty

[zotbox]

Thank you very much for your kind offer Sooty, I will let you know if I can't get access to the files myself.

Cheers,

Zotbox

[Blacksheep]

Yes, REStricted INtensity would sound about right. The ordinary nav lights had a dim/bright selection and the position lights were on a separate circuit with no dim selection; I can't remember what rating the filaments were.

Edit: On another BB they were discussing Mosquito lights and the Resin Lights on a Mossie in a US museum were mentioned as having a metal cover with a vertical slit that restricted the viewing angle of the light to within a narrow angle directly to the rear of the aircraft. I never saw such covers, but that configuration would be logical in wartime conditions.



REStricted INcidence perhaps?