Hawker Single Engined Night-Fighters (Hurricane & Typhoon)

[Jemiba]

In Ian Whites "The History of Air Intercept (AI) Radar and the British Night-Fighter 1935-1959",
I stumbled across a description of two Hawker Hurricane IIs (Z2509 and BN 288), that were fitted
with AI Mk. VI radar sets. The location of the antennas are roughly described (in the sketch below:
transmitter: red, receiver azimuth: blue, receiver elevation: green), but no photo or drawing is shown.
Though there are a lot of photos and drawings of Hurricane nightfighters around, still yet I haven't found
any of those two radar equipped test beds. Anybody else ?

 

[CostasTT]

I got curious and, fortunately, my Google-fu was strong today.
Voilà:
http://jsircar.blogspot.gr/2011/09/hawker-hurricane-ii-c-nf-forgotten.html

 

[Jemiba]

Great, many thanks. This antenna installation is different fom the dscription, but, as the article you've found
mentions, the development was done in "incremental steps" and as the mentioned book describes, there were
still many unforeseeable problems then, needing constant changes.

 

[CostasTT]

You are welcome. From what I can see, the configuration of the antennae is rather similar to the experimental installation of the AI Mk IV on a Typhoon.

 

[Arjen]

Side view of Typhoon nightfighter. Source: 'Jachtvliegtuigen W.O. II' by Bart van der Klauw, Uitgeverij De Alk, ~1972

 

[Jemiba]

Side view of Typhoon nightfighter. Source: 'Jachtvliegtuigen W.O. II' by Bart van der Klauw, Uitgeverij De Alk, ~1972

Do you know, if the underwing pod was used for the radar ? This method was proposed for the Huricane, too,
but rejected, as is said in "The History of Air Intercept (AI) Radar and the British Night-Fighter"

 

[CostasTT]

They are standard Hurricane-type underwing drop tanks, the first type cleared for the Typhoon IB. They were carried because the radar equipment necessitated the deletion of fuel tanks from the wings to make space for it.
Photo from the Squadron/Signal Typhoon/Tempest book, showing both the underwing tanks and radar antennae to advantage:

 

[Jemiba]

From the mentioned book, page 105:
".. The requirement for the new night-fighter stated that the AI equipment was to be capable of installation
in a container the same size and shape as a standard 44 gallon (200 litres) under-wing fuel tank. Provided
with two such "tanks" ballasted to represent the operational weight of11,900lbs (5,400kg), R7881 recorded
s maximum speed of 368 mph (590km/hr). .... " ???

 

[CostasTT]

OK, now that's just confusing... ???

 

[Jemiba]

Well, the whole installation in the Typhoon was still a mock-up then, as far as I understand.
Installing the radar components in the aircraft probably was difficult, due to the limited space
available. The Huricane was tested as a stop-gap measure during the end of 1941, when there
was a shortage of twin-engined types with sufficient performances. So, squeezing those black
boxes into the fuselage of the Hurricane probably was regarded as an acceptable and faster
method, but during 1943, when the Typhoon entered the night-fighter scene, the pressing need
for more night-fighters may have had decreased, so that a better solution was looked for. And
one, that probably would have allowed a faster re-modification to a day-fighter. Just my two cents ..
(I've changed the title of this thread somewhat )

 

[CostasTT]

Considering that all sources mention the fitting of full radar, I'd say it was a test installation rather than a mock-up. To further confuse matters, one source mentions the radar as a Mk VI, whereas all others refer to it as a Mk IV...
In addition, the intention might have been to eventually have a podded installation, but the radar components themselves could have been installed internally in the aircraft.
Furthermore, I'd say they'd be better off with an American AN/APS-4 (ASH or AI Mk XV in British parlance) podded radar installation under the wing or an AN/APS-6 leading edge pod. A Firefly-like underfuselage rack for the AI Mk XV would not be outside the realm of possibility either...

 

[Justo Miranda]

Hi

 

[Jemiba]

Furthermore, I'd say they'd be better off with an American AN/APS-4 (ASH or AI Mk XV in British parlance) podded radar installation

Certainly a true podded radar only could be a centrimetric radar like the AN/APS-4, but that wasn't available
before the end of 1943/beginning of 1944, I think.

 

[alfakilo]

hi

The last sentence in that picture really gets to the heart of the matter.

 

[Jemiba]

The earlier radar sets probably were harder to handle, than later ones, but from what I know,
principally the idea of a radar equiped single seat night fighter wasn't that bad. The Grumman
F6F-5N and Vought F4U5N proved it later, I think. And, as mentioned in "The History of Air Intercept
(AI) Radar ...", at least in 1941 there still was the problem of the available twin-/multi seat night
fighters being to slow in comparison to their prey, so that often even those bombers already located
with radar couldn't be reached and shot down. The single seater was regarded as a measure against
those failures and during the night the Hurricane pilot at least hadn't to bother about Bf 109.

 

[CostasTT]

Furthermore, I'd say they'd be better off with an American AN/APS-4 (ASH or AI Mk XV in British parlance) podded radar installation

Certainly a true podded radar only could be a centrimetric radar like the AN/APS-4, but that wasn't available
before the end of 1943/beginning of 1944, I think.

Had the requirement for a single-seat night fighter persisted, these would have been the viable options and thus worth mentioning. While researching the subject, I found this blog, which includes several mentions of ASH-equipped Mosquitoes, which reinforces my point.

 

[Jemiba]

..., which includes several mentions of ASH-equipped Mosquitoes, which reinforces my point.

Not sure, that we aren't running into a misunderstanding. No doubt, that the Mosquito used
such a radar installation in a thimble nose (the first was the NF Mk.XII, converted NF Mk.II,
brought into service in 1943). But the Mosquito had enough internal space (although the machine
guns had to be removed). The radar sets used in 1941 would probably have needed at least two
podds and even then, the antennas (still dipole antennas) needed to be placed somewhere else on
the aircraft.
A crew of two is certainly preferable for a night-fighter, handling the radar is done by one of them,
flying the aircraft by the other, not to mention the worthwhile "second pair of eyes", especially in the
darkness and with a radar having a minimal range of still several hundred meters. But the US Navy
proved, that a single seat night-fighter was possible, using a radar, that, with regards to handling
probably wasn't way ahead of the radars in 1941/42.

 

[CostasTT]

OK, maybe it was a bad choice to use a twin engined, multi-seater aircraft as an exampl, but it illustrates the use of this type of radar in air-to-air combat by the RAF.

 

[Jemiba]

Ah, ok, get your point now, I think.
The ASH (AN/APS-4) was a kind of multi-mode radar, that could be used for surface search (giving it
its name Air-Surface-Homing), navigation and air intercept. Quite a good description here:
http://www.ibiblio.org/hyperwar/USN/ref/RADTWOA/RADTWOA-2.html#an/aps4

 

[Petrus]

Here is a link to a British "Introductory Survey of Radar. Part II" in which there is a chapter on the AI Mk. VI radar for single-seat fighters (namely night fighter versions of the Hurricane):

http://www.vmarsmanuals.co.uk/archive/632_AP1093D_Pt2_Introductory_Survey_of_Radar_screenread.pdf

Piotr

 

[Jemiba]

A very interesting report, especially as it wasn't written with too much hindsight, thank you for pointing us
to it.
A point actually against the single seater I had forgotten before, is the deterioration of the pilots night vision,
that should be expected, when regularly looking onto the indicator tube.
But the USN seems to have been quite happy with theirs ...?

 

[Petrus]

A very interesting report, especially as it wasn't written with too much hindsight, thank you for pointing us
to it.
A point actually against the single seater I had forgotten before, is the deterioration of the pilots night vision,
that should be expected, when regularly looking onto the indicator tube.
But the USN seems to have been quite happy with theirs ...?

If I am not mistaken, the US Navy issued red-glass spectacles for their night fighter pilots.

 

[Jemiba]

Red spectacles ? Wouldn't it have been a kind of "sunglasses at night" ?
Have searched on my own and it was written on one site, that the instrumentation lighting
was changed to red, similar to the lighting in submarines, I think.

 

[Arjen]

The human eye has two kinds of light-receptor cells: three types of colour sensitive cones, one type of colour insensitive rods. Cones allow you to discriminate between colours, rods allow you to perceive really low light levels. The central area of the retina contains only cones. If it's dark, looking slightly askance of what you're hoping to see sometimes helps you to to see it, because its image is projected on a part of the retina that actually contains rods.

The human eye as a whole is most receptive for light in the green part of the spectrum. The theory behind putting on red-coloured spectacles is that they filter out green light, and that night vision is only lost in the red part of the spectrum - which is the part of the spectrum where human eyesight isn't that good anyway. If the theory holds, night-vision should be retained to some degree in the green part of the spectrum. Put on spectacles before looking into the scope, remove spectacles before looking outside.

In practice, the colour insensitive rods will lose night vision by exposure to red light almost as easily as by exposure to green light. Using red spectacles (or a red display) serves to retain some night vision in the colour part of your vision, but your low light level vision will be shot anyway by peering into the scope. It will help slightly to spot things you're directly looking at, the trick of looking at something askance will be much less effective.

I don't know how this has been taken into consideration with present-day cockpit design.

 

[Jemiba]

...Put on spectacles before looking into the scope, remove spectacles before looking outside.

Wouldn't a red filter on the scope do the trick then ?

The human eye has two kinds of light-receptor cells: three types of colour sensitive cones, ...

Quite OT, but some kind of human beings actually and scientifically proven have FOUR types of cones,
giving them truely a better colour vision. Those human beings all are from a species called "women",
just for you to consider, before you'll start a discussion about colours the next time ....

 

[Arjen]

...Put on spectacles before looking into the scope, remove spectacles before looking outside.

Wouldn't a red filter on the scope do the trick then ?

Yes. Or a display that emits red light.

The human eye has two kinds of light-receptor cells: three types of colour sensitive cones, ...

Quite OT, but some kind of human beings actually and scientifically proven have FOUR types of cones,
giving them truely a better colour vision. Those human beings all are from a species called "women",
just for you to consider, before you'll start a discussion about colours the next time ....

I honestly didn't know. Thanks for the heads-up.
From the Pittsburgh Post-Gazette: Some women may see 100 million colors, thanks to their genes

 

[alfakilo]

Wouldn't a red filter on the scope do the trick then ?

Back in the day, that is how it was done.

 

[Justo Miranda]

To combat the German ‘Winter Blitz’ (June-December 1940) there was a proposal to equip the Spitfires, Hurricanes and Typhoons day fighters with a radar set specifically designed to single-seaters operation.

In 1941, the EMI engineering team developed the AI Mk.VI, one 10 Kw Airborne Interception radar, with 500 ft to 3 miles detection range and automatic range strobe, dispensing with the need for an operator.

In April 1942 the new radar was tested in combat by some Defiants Mk.II of the Nº 264 Sqn and the order for twelve Hurricane Mk.IIC (NF), fitted with AI Mk.VI radar, was placed.

The prototype (BN288) flew on June 1942. Early flight trials with the Mk.VI radar set showed an undesirable shortcoming: the night vision of the pilot would be quickly destroyed by the radar screen glare.

Air Military publication, written in September 1943, describes the difficult task of watching the 4-inch diameter cathode-ray tube and looking out in the darkness for the enemy.

The Germans partially solved the problem using anti-glare red filters in the radar screen, anti-glare red pilot goggles and ultra-violet illumination for the instrument panel of their single-seat night fighters.

In November 1942 six Hurricane Mk.IIC (NF), fitted with wing-mounted transmitting dipoles type 69, Azimuth dipoles vertically polarised and elevation antennas type 29, were delivered to the Nº 245 Sqn and another six to the Nº 247 Sqn for operational trials.

The new fighter was found top-heavy and difficult to handle, the drag generated by the antennae and the long-range fuel tanks required to give extended patrol endurance, considerably reducing the top speed and the airplane was unable to catch the new German night intruders Junkers Ju 88 A-4.

Early 1943 all the Mk.IIC (NF) were shipped to India.

On June 1943 were delivered to the Nº 176 (NF) Squadron for the defence of Calcutta from the Ki.21, Ki.48, G4M and H6K Japanese night raiders.

The Mk.IIC (NF) remained operational until January 1944.

 

[cluttonfred]

A pilot flying a single-seat fighter around in the dark and oh, by the way, running the very primitive air intercept radar at the same time. What could go wrong? I'd be curious to hear how the overworked pilots flying the Mk.IIC (NF) fared against those Japanese opponents over India. The H6K would have been easy prey, the G4M less so, and the Ki.21 and Ki.48 were pretty fast for the day.

 

[Arjen]

Not a Hurricane, but a Typhoon with radar. Second image from wiki.

 

[Jason Dykstra (Wyvern)]

Should we merge the other topic (https://www.secretprojects.co.uk/th...gined-night-fighters-hurricane-typhoon.20585/) with this one?

 

[Jason Dykstra (Wyvern)]

Also, does anyone know how the Hurricane Night Fighter faired in the Far East?

 

[EwenS]

I've dug out Vol 3 of "Bloody Shambles". They arrived in May 1943 (with a very blurry photo making it impossible to see details of the aircraft) in B flight and they lacked armour plate.

The only action that they are noted as having taken part in was on 5th Dec 1943, when 4 aircraft were ordered up to intercept an IJAAF raid in daylight, mid-morning, but were back on the ground again half an hour later at 11.00am having been recalled and replaced in the air by Hurricanes of 67 & 146 squadrons. Then at 11.30am a second wave of IJNAF attackers was detected on radar and 176 launched a Beaufighter flight but, as they couldn't gain altitude fast enough, another 5 Hurricanes of 176 were sent off 10 mins later. 3 of 176's Hurricanes were shot down by escorting Zeros, with 2 pilots killed, and at least one other damaged, landing "riddled with bullets". Japanese losses from both waves totalled a single IJAAF Ki 21 bomber, but to what cause is unknown.

The next reference was that by Jan 1944, 176 was reverting to Beaufighters only in view of the losses of 5th Dec, and the last of the experimental AI Hurricanes had gone by 3rd Jan.

 

[overscan (PaulMM)]

Merged topics.

 

[Hood]

Commanding Far Eastern Skies by Peter Preston-Hugh (part of the Wolverhampton Military Studies Series) oddly makes no mention of the NF Hurricanes.
It mentions the raids on Calcutta during 20-27th Dec 1942 and that Pierse requested a flight of night fighters. Preston-Hugh mentions a flight of Beaufighters from 89 Squadron were sent immediately and arrived on 14th Jan 1943 (a mix of Mk.I and Mk.V airframes), being issued to 176 Sqaudron. The author does go into the day-fighter Hurricanes and their effectiveness in some detail but does not mention the night-fighter conversions at all or any impact they made.

He does state various sources that were unhappy with the Hurricane and considered it obsolete by the end of 1943 but ground control and radar control problems had far more impact on the success or failure of interceptions even into early 1944. So its likely a handful of AI Hurricanes would have had little impact and of course Beaufighters were superior anyway. They were probably sent to India for the want of better equipment.

 

[Justo Miranda]

On March 1943 the Typhoon Mk.IB (R7881) was modified by Hawker with the installation, into the starboard wing fuel tank housing, of the AI Mk.IV radar with automatic-range auto-strobing set.

The prototype was fitted with two (fixed) 44 gallon underwing tanks, anti-dazzle exhaust stacks, Type I Mk.II (N) reflector gunsight, wing-mounted Type 69 transmitting dipoles, Azimuth dipoles vertically polarised Type 29 and elevation antennae installed in both wings.

The aircraft with a maximum weight of 11,900 lbs. was redesignated Typhoon Mk.IB (NF) and painted in Dark Green/Medium Sea Grey uppersurfaces and Medium Sea Grey undersurfaces.

On April 1943 the radar was evaluated at the Royal Aircraft Establishment (RAE).

In November the prototype, fitted with a four-bladed Rotol airscrew and underwing identification stripes, was operational tested over London by FIU pilots, reaching 368 mph top speed.

At the end of 1943 the pressing need for faster night fighters may have had decreased with the availability of the Mosquito NF series.

It was considered that flying at night while operating radar would have an excessive workload for the pilot and the project was discontinued.