WW2 Aircraft more successful in secondary role

[pbehn]

"The P-51 (NA-73) interred service as an Army coop (close air support) low altitude fighter."

You keep repeating this but it is highly debatable.
It was not designed as such, and while to was assigned to Army co-operation squadrons (at least they were named that) it did a lot more recon/photo recon in it's early operational deployments. Due to a rather notable lack of boots on the ground (Dieppe being a major exception) there was a distinct lack of actual Army Co-operation missions in Europe until 1944.
There were a lot of "tactical" or low altitude strikes against railroads, barges and airfields during 1942 and 1943 but there were no Army ground troops to support no matter what the squadrons were named.
If you are not actually supporting the Army and the majority of planes have 1-3 cameras fitted is the plane really a close air support fighter?

The problem for the P,51 in this respect is that it was put in service first by the R.A.F. they had no bombers to escort in daylight across the channel most objectives were at ground level.

 

[wuzak]

For it's success in not one, but multiple secondary roles, it's hard to beat the P-38. While designed as an "interceptor" it performed a wide variety of roles.
Long range escort fighter
Ground support/fighter bomber role
Dive bomber
Skip bomber
4000 lb bomb load capability
Tested as a torpedo bomber, carrying (2) 2000 lb torpedos
Photo-recon aircraft-one of the most successful of the war
High altitude level bomber with "droop snoot" variants equipped with Norden bombsites
Radar equipped Pathfinder
Night fighter

Did it perform any of those better than its primary role as fighter?

Radar equipped Pathfinder

Really?

Tell me more please. I hadn't heard of this role.

 

[Greg Boeser]

I have a couple of suggestions for contenders:

The Kawasaki Ki 45. In many ways it can be called the Japanese Bf 110, with the reservations that it was later, slower and build in fewer numbers. It never served in it's intended role as long range escort but did fly as a bomber interceptor. It did see much service (and improvements to enhance capability) in the roles of night fighter, ground and sea attack.

Actually, the Ki-45 DID serve as a long range bomber escort in mid '42 over China. And it performed admirably in that role until it encountered AVG interceptors.

 

[gjs238]

Did it perform any of those better than its primary role as fighter?


Really?

Tell me more please. I hadn't heard of this role.

Perhaps he is referring to H2X radar?

Lockheed P-38 Lightning - Wikipedia, the free encyclopedia
The Lightning was modified for other roles. In addition to the F-4 and F-5 reconnaissance variants, a number of P-38Js and P-38Ls were field-modified as formation bombing "pathfinders" or "droopsnoots", fitted with a glazed nose with a Norden bombsight, or a H2X radar "bombing through overcast" nose. A pathfinder would lead a formation of other P-38s, each overloaded with two 2,000 lb (907 kg) bombs; the entire formation releasing when the pathfinder did.

H2X - Wikipedia, the free encyclopedia
In Europe several P-38 fighters were also converted to carrying H2X radar in the nose, along with an operator/navigator in a cramped compartment in the nose behind the radar dish, provided with small side windows and an access/exit hatch in the floor (much like the earlier P-38 "Droop Snoot" bomber-leader variants, but with a radome instead of a glazed nose). These missions were to obtain radar maps of German targets but plans to produce the variant in quantity never materialized.

 

[stona]

I know the quotes are from Wikipedia, but I find it hard to believe that a P-38 (or anything else) could be 'field modified' to carry H2X and associated paraphernalia. Post production? Yes, this was often the case with H2S in British aircraft, but in the field?...

What were they planning to make? A map of H2S images of Germany? Here is an H2S image, taken by the British during testing over the East Midlands. You'll have to take my word for it, but it is a very good image, they were often far more 'confused'.

The solid white line is the bearing the aircraft is flying on. The circle is either ten mile radius or diametre, I can't remember! It was easy for the British too identify Leicester, Loughborough and Melton Mowbray (pork pies!) because they knew where the aircraft was flying. In the absence of any obvious distinguishing feature which would show up on radar, like a river or coastline, it would be impossible for an H2S operator to know what the various areas of reflected energy in his scanner actually represented. They had enough problems doing it visually in daylight.

Cheers

Steve

 

[gjs238]

<SNIP>

What were they planning to make? A map of H2S images of Germany? Here is an H2S image, taken by the British during testing over the East Midlands. You'll have to take my word for it, but it is a very good image, they were often far more 'confused'.

The solid white line is the bearing the aircraft is flying on. The circle is either ten mile radius or diametre, I can't remember! It was easy for the British too identify Leicester, Loughborough and Melton Mowbray (pork pies!) because they knew where the aircraft was flying. In the absence of any obvious distinguishing feature which would show up on radar, like a river or coastline, it would be impossible for an H2S operator to know what the various areas of reflected energy in his scanner actually represented. They had enough problems doing it visually in daylight.

Cheers

Steve

H2X was what was being used, not H2S

H2X - Wikipedia, the free encyclopedia
It differed from the original H2S mainly in its operating frequency which was in the X band rather than H2S' S band. This gave H2X higher resolution than H2S, which had problems over large cities, which appeared as a single mass on the H2S display.

H2X used a shorter 3 cm "centimetric" wavelength (10 GHz frequency) than the H2S, giving a higher angular resolution and thus a sharper picture, which allowed much finer details to be discerned, aiding in target identification.

 

[stona]

H2X was what was being used, not H2S
.

It is effectively the same thing. H2X was the US code for the American 'development' of the British H2S system. Of course the British developed H2S too as the war went one

The early test image I posted was taken using a 10cm wavelength (it's marked on the photograph), later this was reduced to 3cm.

Cheers

Steve

 

[wuzak]

I think Steve was referring to the size of the equipment of H2S/H2X radar.

Here is a picture of a Mosquito experimentally flying with H2S
AIRCRAFT OF THE ROYAL AIR FORCE 1939-1945 DE HAVILLAND DH 98 MOSQUITO (MH 4647)

Here is a B-17 with a retractable radar dome.
http://www.wdnorton.nl/B-17 GSH 42-3486/B-17Gs96thBGwithMickeyRadar-1[1].jpg

Note that the ball turret was removed in this installation.

And an earlier installation
http://www.wdnorton.nl/B-17 GSH 42-3486/EarlyB17H2X Radar an early hand-built .gif

The radar operator's station
https://timeandnavigation.si.edu/si..._radar_-_national_archives_342-fh-3a12719.jpg

 

[stona]

Indeed. Here is the set up of the H2S scanner, as seen from inside the fuselage of a Lancaster looking down into the radome.

Cheers

Steve

 

[wuzak]

Also, it is often said that H2X was an American development (ie better) than H2S. In fact H2X was heavily based on the 3cm ASV radar used by Coastal Command.

 

[wuzak]

A couple of H2S radar scope pictures from 1945

An H2S radar image taken from a cathode-ray tube display monitor on board a Mosquito aircraft of 139 Pathfinder Squadron RAF. The aerial view, from 24000 feet, shows the areas affected by fires ...
An H2S radar image taken from a cathode-ray tube display monitor on board a Mosquito aircraft of 139 Pathfinder Squadron RAF. The aerial view, from 25000 feet, shows the areas affected by fires ...

The second one was taken from a Mosquito. The Mosquito was similar in size to the P-38, but was designed at the outset to be a 2 seater, and the H2S radar was fitted under the fuselage, using space in the bomb bay, going by the picture of the test model earlier.

The 8th AF also used, experimentally, Oboe Mk I. At the time the RAF BC had moved to Oboe Mk II and Gee H, but feared that the Germans would get a hold of the system more easily with US bombers carrying them too, and thus be able to counter the system.

 

[Shortround6]

Last photo was taken in Burbank, CA. The planes carried AN/APS-15 radar.

 

[stona]

Those are much more typical images. It's not hard to see why bombing accurately by such a system was impossible. Sometimes a really good and recognisable image could be achieved.
This is another British test image, clearly showing the River Humber and its estuary. Hull would be just west of the top of the larger bend in the river, but unless you know that you can't see it.

Cheers

Steve

 

[stona]

Nice pictures! They certainly don't look like modifications done in the field.

Cheers

Steve

 

[wuzak]

Well, there you go....

Only thing, the radar seems to be pointing in the wrong direction - forwards, not downwards.

 

[stona]

Also, it is often said that H2X was an American development (ie better) than H2S. In fact H2X was heavily based on the 3cm ASV radar used by Coastal Command.

H2X (operating in the X band) was an Ameican development of H2S. The British too developed H2S operating in this band with a 3cm wavelength. H2S III, the most commonly used type from early 1944 on, did precisely that.
Cheers
Steve

 

[gjs238]

Those are much more typical images. It's not hard to see why bombing accurately by such a system was impossible. Sometimes a really good and recognisable image could be achieved.
This is another British test image, clearly showing the River Humber and its estuary. Hull would be just west of the top of the larger bend in the river, but unless you know that you can't see it.

Cheers

Steve

Is that H2S or H2X?

 

[Shortround6]

A different Wiki article (one on the AN/APS-15 radar) says that the P-38s were being used to make radar maps, much a like a number of mosquitoes were being used. This particular radar seemed to overload the Mosquitoes electrical system (or poor installation?) causing a number of failures and even lost aircraft.
The radar operator sat (squished?) behind the radar under the clear panel shown in the photos. The radar itself weighed about 370lbs and with the removal of the guns/ammo weight was probably not a big issue.

In one spec sheet for the radar it was claimed it could pick a harbour buoy at 15 nautical miles.

The Pacific War Online Encyclopedia: APS-15 Airborne Radar

 

[stona]

Is that H2S or H2X?
H2S

It's the same thing. H2X is just the American code, they chose X because that is the frequency band it operates in (roughly 7-11 GHz), why the British chose H2S is a subject of some debate. R V Jones gives one entertaining explanation. The early H2S worked on a longer, 10cm, wavelength, but the American H2X and later versions of H2S both operated at 3cm.
Wavelength x Frequency = Speed of Light (c), which makes one easy to work out if you know the other (and c of course)

Both were derived from the work of Randall and Boot (at Birmingham University, just up the road from where I'm sitting) on the cavity magnetron, which had been around for several years by the early 1940s.

Cheers

Steve

 

[stona]

Spot the difference.

Here is an H2X image, taken by a US aircraft on 6th June 1944.

The invasion coast runs across the image. The bright spot at about 7 o'clock is Caen.

Cheers

Steve