Thread by @TrentTelenko

@smooreBofB1940,@Bis18marck70, @NavalHistWar, @MilHiVisualized,
@CBI_PTO_History, @marinemuseum_nl, @WorldofWarships, @JamesTTHalstead, @Balloons2Drones, @crusaderproject, @AirPowerHistory

This is a thread on UK Night Fighter C3I and comparing various WW2 military power's...

..."Fighter-Searchlight teams" with the UK's lack of
same.

Steven Moore did a comparison of UK Fighter Command's four night fighters of the 'Blitz' that followed the Battle of Britain and particularly that of the radar equipped Beaufighter's evolution from meter to centimeter band radars.

See:

https://twitter.com/smooreBofB1940/status/1181289445590523911

While Mr. Moore has a point regards the Beaufighter.
I think his thread is lacking the context of the command control communications and intelligence (C3I) system that was growing from near nothing in 1940 to a huge and complex organism by 1943.

AI radars are the least of it.

In addition to the network of GCI radars Mr. Moore mentions. There were networks of radio, radar and visual navigation beacons on the ground, generations of IFF transponders, a lot of technique between the GCI radar controllers and air crews, plus between pilots
and RIO crews.

See USMC LTC Edward Montgomery at link & text screen shots

researcheratlarge.com/Aircraft/USMC_…

The USN's NavAir Bureau did not like RAF style night fighters.

And there was the integration of intelligence in the form of both "Y-Service" intercept of Luftwaffe signals and Bletchley Park Ultra decodings.

I cannot recommend Aileen Clayton's "The Enemy is Listening" more in understanding the "I" in the UK's night fighter C3I system.

Amazon link to "The Enemy is Listening"

amazon.com/ENEMY-LISTENIN…

The multi-redundant C3I system LTC Montgomery described in 6/43 was not there in 1940.

The thread bare nature of RAF 1939-1940 high tech was well laid out in the first episode of late 1970's BBC "The Secret War"

Link:
dailymotion.com/video/x123i1g_…

And it was not just matters of the RAF stealing medical diathermy sets for beam jamming or telephone lines from junior officers.

The D/F gear used to "home" night fighters was the same gear used RAF "Y-Service" intelligence to locate enemy emitters.

---

Ed Drea's essay "A Signal Intercept Site at War" in his "In The Service of the Emperor" has a passage (pg 119) on the turf fight between Australian Army "55 Wireless Intercept" unit and the RAAF Fighter Sector commander at Port Morsby in 1942...

... over the use D/F gear for "homing" versus intelligence that would have shown up in the 1940-41 period in the UK.

See:
nebraskapress.unl.edu/university-of-…

Neither the Fighter Command radar or visual beacons originated inside Fighter Command.

The radar beacons used for the Mark IV AI radar originated with Sqdn. Ldr. Lugg of RAF Coastal Command.

See:
British ASV radars
by Emmanuel Gustin
uboat.net/allies/technic…

Henry Guerlac's "Radar in World War II" has this passage on the RAF's development of radar beacons or "Racons" in the night fighter role.

As best I have been able to determine, the coded visual light beacons LTC Montgomery spoke of in June 1943 seems to have originated as a Luftwaffe Nachtjad navigation technique that Fighter Command copied as soon as they learned about it through intelligence channels.

When it comes to the UK GCI radar system and associated IFF gear. The period of Dec 1940 to late 1942 saw the crash developed, kit-bash, 200mhz AMES Type 8 developed from the British Army GL Mk II...

...followed by the "clean slate" AMES Type 7 GCI radar design at the same frequency.

See:
en.wikipedia.org/wiki/AMES_Type…

That period also saw, count them seven different IFF systems -- "Pip-squeak", Mark I IFF, _THREE_ generations of Mark II IFF and two kinds of Mark III IFF transponders.

See Guerlac screen shot & links:
qsl.net/vk2dym/radio/i…
en.wikipedia.org/wiki/IFF_Mark_…

All that technological change, that rapidly, require a whole lot of "Learning by doing. Learning by dying."

And the biggest cause of "Learning by dying" was the UK identification friend or foe (IFF) systems.

While "Pip-squeak" was replaced. The proliferation of newer IFF systems and increased UK & US aircraft production rates meant there were not enough of the newer IFF systems to retrofit older planes.

Screen shot of pg 429 of "Development of IFF in the Period up to 1945"

Until full transition to the Mark III IFF in late 1943 in Europe. Every single Mark I thru III IFF could and did show up in battle.

During the July 1943 invasion of Sicily, RN light AA cruiser HMS Dehli saw Mark III, Mark IIN, Mark IIG, Mark II, Mark I IFF or nothing at all.

Which bring's up the point that Allied IFF training and maintenance left much to be desired.

See the various attached American military IFF posters.

These UK Night fighter C3I problems above bring up a very important point.

Radar was the beating heart of the Dowding System. It was RAF Fighter Command's hammer looking for a nail.

This and other UK technology limits precluded the "Fighter-Searchlight Team" other powers used.

Most readers familiar with UK night fighters are aware of the two German Nachtjad radar-less fighter and radar guided searchlight tactics the Luftwaffe used over Europe.

Himmelbett and Wilde Sau.

FYI -- Michaël SES Svejgaard's web site is a must see for Luftwaffe night fighter control methods

See:

Helle Nachtjagd Verfahren
gyges.dk/Himmelbett.htm

Wilde Sau.
gyges.dk/Wilde%20&%20Za…

But almost no one who knows of European night fighter operations knows anything at all of the "Fighter-Searchlight teams" used by the USAAF or IJNAF in the South Pacific.

The single seat USN & USMC F6F-3(N), F6F-5(N) and F4U-2 Corsair eat all the Pacific night fighter O2.

And if there is any O2 left in the room, the early SCR-540 radar equipped twin engine USAAF P-70 of the 6th Night Fighter Squadron and USMC PV-1 of VMF(N)-531 take it.

Two good examples -

U.S. Night Fighter Radars of WWII
by Thomas Wildenberg
ibiblio.org/hyperwar/USN/r…

MARINE NIGHT FIGHTERS
April 20, 2012
by Mitch Williamson
weaponsandwarfare.com/d5777-vvvvghj/

This is a shame as the 3rd version of the USAAF "Fighter-Searchlight Team" Doctrine is on-line for down load.

See:
Fighter-Searchlight Team, The; Instruction Text
mobileradar.org/documents.html

This doctrine was originally written by "Project X" AKA the 6th Night Fighter Squadron on Guadalcanal when they found their P-70 could not get up to 20,000 feet or higher where most Japanese night attackers were.

The pie chart came from the following on-line US Army document:

Antiaircraft Artillery Activities in the Pacific war.

cgsc.contentdm.oclc.org/cdm/compoundob…

So the 6th Night Fighter Squadron got several P-38's and teamed them with SCR-268 searchlight radars.

The P-38 circled at 30,000 feet and were given vectors from the SCR-268's to pounce on the Japanese night raiders.

The 6th Night Fighter Squadron later field converted a couple of either P-38F or P-38G fighters with twin seats and SCR-540 radars in early 1943.

See:
modelingmadness.com/review/allies/…

The attempt to follow up these field modifications with a production line P-38 night fighter fell into USAAF procurement bureacracy hell.

The single seat P-38 Night fighter with an AN/APS-4 "ASH" radar "failed."

The competing, early model, SCR-720 radar equipped, P-61 arrived in the Pacific, but had the same 20,000 plus feet altitude problems as the P-70.

So the "Fighter-Searchlight Team" was dusted off by the 13th Air Force to defend Morotai with P-38's and RAAF Spitfires.

The altitude failures of the P-61 at Morotai and Leyte had General Kenney of FEAF again request a two seat P-38 night fighter. This revived night fighter was the P-38M and it missed the war.

The story of the last "Fighter-Searchlight Team" involves the redoubtable Commander Yasuna Kozono (left) of the IJNAF's 251st Kōkūtai (formally Tainan Air Group) in Rabaul.

In early 1943 he came up with the idea of installing pairs of upward and downward firing 20 mm cannon...

... in a Nakajima J1N1-C as a night fighter.

This was independent of and pre-date the German Schräge Musik upward firing cannon system.

en.wikipedia.org/wiki/Schr%C3%A…

By this time in 1943 Rabaul was surrounded by an extensive radar network and had deployed a "Heavy Flak Grand Battery" with many search lights.

Like the Germans in 1944, the Japanese in 1943 "Grand Flak Battery" lacked enough gun directors for the heavy cannon deployed.

The Allied 4-engine B-17's, B-24 and 2-engine Hudson bombers attacking Rabaul in 1943 were at extreme range, had predictable routes and radar informed times of arrival.

In three months from May - July 1943, the two Nakajima J1N1-C Gekko (Allied code name Irving) night...

...fighters and search lights at Rabaul killed seven USAAF B-17, one RNZAF Hudson, and one USN PB4Y (B-24), probably killed another USAAF B-24 and damaged another B-24.

See:
pacificwrecks.com/people/veteran…
pacificwrecks.com/people/veteran…

Why the RAF never developed the "Fighter-Searchlight Team" boils down to the absolute worse military procurement decision made by the government of Great Britainof the 1930's not to pursue a tachymetric anti-aircraft fire control systems.

This despite the US Navy deploying the Mark 19 director in the early 1930's which did.

See:
The British High Angle Control System (HACS)
By Tony DiGiulian
navweaps.com/index_tech/tec…

A tachymetric anti-aircraft fire control is an analogue mechanical computer -- also called a "director" -- that generates target position, speed, direction, and rate of target range change, by computing these parameters directly from measured data.

See:
en.wikipedia.org/wiki/Tachymetr…

The target's range, height and observed bearing data -- from optical, sound or radar instruments -- are fed into analog mechanical computer. Which then uses the measured change in range, height and bearing from successive observations of the target to compute the true range,...

..direction, speed and rate of climb or descent of the target.

These computers required some amount of time - 10 seconds to up to a minute - for a stream of steady electrically transmitted data to compute a proper fire control solution for aiming the guns and fusing time shells.

While the High Angle Control System (HACS) was bad for the Royal Navy. It was worse for the British Army, whose Vicker's heavy anti-aircraft gun directors were not capable of receiving electrically transmitted range, height & bearing measurements.

The upshot was the UK had the worse directors of any major power going into WW2 with Japan very slightly better in that some of the IJN's best directors took electrical data.

The Germans and Americans both had tachymetric mechanical analogue directors going into WW2.

The important thing for the Fighter-Searchlight team story was their directors could automatically aim seachlights as well as guns while Britain's could not.

That meant no Fighter-Searchlight team for the RAF in the Blitz.

The bottom line was all four WW2 military powers did things their own way because they had a different technological tool sets.

Understanding what those tool sets were and how they affected the decisions of the major powers are still very much unexplored historical territory.

Whoops...these didn't attach where they needed too