Picture of the Day - Miscellaneous (2 Viewers)

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

I have found the Komainu (Korean dog) at Utou Shrine :)

20221125-042849_jWkUMAxmD6.jpg

Source: 善知鳥神社(青森県青森駅)の投稿(1回目)。現在の青森市が善知鳥村と呼ばれていた頃、この地を…[ホトカミ]

Korean dog (Pug).
Origin China.
Komainu.jpg

Source: 狛犬ポーズ(youtubeも宜しく) - パグ犬の、ガングロビクとおかまチビのお話し
 
Last edited:
IJA 15cm AA gun.

On August 1, 1945, this gun shot down 2 B-29s flying 33,000 feet over Tokyo.
A former IJA staff Masahide Hotta testifies "According to GHQ's explanation in the postwar when I was interviewed there, they stopped bombing the southern area of Tokyo until they confirmed if it was by new rocket or plane."

IJA_15cm_AA_gun.jpg

Source: KAIKOU magazine for veterans(Mar.1990)
 
Last edited:
Develpment code
IJA Mark TA kai model 4 radar

Formal designation
Kai model 4 radar

Frequency: 200 MHz
Output: 10KW
Detective distance: 40km
Distance accuracy: +/- 100meters
Angle accuracy: +/- 1 degree
Altitude accuracy: +/- 1 degree

Kai_model_4_radar_a.JPG
Kai_model_4_radar_b.JPG

Source: KAIKOU magazine for veterans(May 1990)
 
Develpment code
IJA Mark TA kai model 4 radar

Formal designation
Kai model 4 radar

Frequency: 200 MHz
Output: 10KW
Detective distance: 40km
Distance accuracy: +/- 100meters
Angle accuracy: +/- 1 degree
Altitude accuracy: +/- 1 degree

View attachment 709137View attachment 709138
Source: KAIKOU magazine for veterans(May 1990)
I wonder what year this radar was deployed? A VHF system, and only 200MHz at that, is a primitive system that has very poor resolution compared with X-band systems that were in the field late in the War. Development of the cavity magnetron by the British was a MONUMENTAL advance that, in my opinion, has not received enough credit. Our 1960 Corporal Missile system employed a WW II radar system- SCR584- that was an X-band system for tracking the missile trajectory..
 
I wonder what year this radar was deployed? A VHF system, and only 200MHz at that, is a primitive system that has very poor resolution compared with X-band systems that were in the field late in the War. Development of the cavity magnetron by the British was a MONUMENTAL advance that, in my opinion, has not received enough credit. Our 1960 Corporal Missile system employed a WW II radar system- SCR584- that was an X-band system for tracking the missile trajectory..
Probably in 1945 as the next model of 600Mhz was not in time for the war.
 
The radar the British used to help win the BoB was an HF radar, designed that way because it was easier to generate high power at the lower frequencies and the RAF figured that bombers were the main threat and thus used the bomber wingspan as guidance for radar wavelength rather than the fuselage diameter.

In the book on skip bombing (which it was not, by the way) they say that the B-17's operating on anti-ship missions at night added ECM and found that the Japanese fighters seeking to intercept them were emitting radar signals as early as late 1942.

I was doing a study for NASA and was surprised to find out how early the highly sophisticated Nike Ajax SAM system was deployed in the US, only about 10 years after the end of WWII. Considering how many of those missiles were deployed the safety record was good; there were only a couple of serious mishaps. A Nike Ajax missile at Ft Meade was fired accidentally at airliner and a Nike Ajax site in NJ suffered a massive explosion that led to one missile launching.
 
The radar the British used to help win the BoB was an HF radar, designed that way because it was easier to generate high power at the lower frequencies and the RAF figured that bombers were the main threat and thus used the bomber wingspan as guidance for radar wavelength rather than the fuselage diameter.

In the book on skip bombing (which it was not, by the way) they say that the B-17's operating on anti-ship missions at night added ECM and found that the Japanese fighters seeking to intercept them were emitting radar signals as early as late 1942.

I was doing a study for NASA and was surprised to find out how early the highly sophisticated Nike Ajax SAM system was deployed in the US, only about 10 years after the end of WWII. Considering how many of those missiles were deployed the safety record was good; there were only a couple of serious mishaps. A Nike Ajax missile at Ft Meade was fired accidentally at airliner and a Nike Ajax site in NJ suffered a massive explosion that led to one missile launching.
The Battle of Britain was early in the War and HF/VHF radar was the best they had at that time. After the cavity magnetron was invented (I think it was in the Cavendish Laboratory, UK), microwave systems with orders of magnitude better performance were rapidly developed by the US & Britain. These were notable for the destruction of the U-boats when they were installed in ASW aircraft. No longer could U-boats surface during the cover of darkness to charge their batteries without being detected on airborn radar. Schnorkel development helped but did not completely solve this problem. AA guns were developed with gun-laying radar as well.
Two main characteristics of a good early radar were range and angular resolution. Range depended on antenna gain, receiver sensitivity, and transmitter output power. Receiver sensitivity did not undergo any really marked advances throughout the war so that was a relative constant. A parabolic (dish) antenna's gain was a function of how many wavelengths it was in diameter, so going to microwave frequencies allowed huge gains to be achieved in moderate antenna sizes. Correspondingly, as antenna size increased, beamwidths also shrunk, allowing better angular resolution. The cavity magnetron produced 10s of kilowatts or even more of peak power, a far higher output than previously possible. In addition it produced short pulses with fast rise times, essential for accurate range measurements. Other advances such as Autotracking, helical scan feeds, PPI, etc put the Allies far ahead of Japan and even the Germans (Wurtzburg, Giant Wurtzburg, etc.). WW II technology was a move/countermove chess game.

BTW, I bought a Nike Ajax rocket engine in the salvage yard at Redstone Arsenal years ago with the thought of maybe doing something dramatic with it. Then I found out that it burned 2,000 lbs per SECOND of fuel/oxidizer. I sold it to a collector back east a few years ago. :)
 
All of the props on the 29s are lined up for the photo. The cars appear to have fat fenders except for the station wagon inside the fence at the left. That one could be a 49-52 Ford.
 
Walker AFB was at Roswell, NM, and it does not appear to be there. I agree that it looks like the Midwest, but it could be just about anywhere East of the Rockies. That ramp looks like it could hold at least a hundred PT-17's which appear to be the biplanes, but if they wanted to crank up those B-29's they are going to have some problems keeping out of each other's way. The hanger looks to be well sized to handle PT-17's but certainly not B-29's. That is an impressive and neat facility but it's much larger than a Base HQ would ever have to be, so I assume it was built for primary instruction ground school.

As for timeframe, the insignia does not have the red bars, so it likely would predate the creation of the USAF and the fact that PT-17's are still in service to some degree shows it to be not long after the end of WWII. I don't know how long they kept PT-17's in service but I'd guess it was less than a year after VJ Day. The fact that the road runs between the buildings and the flight line with minimal barriers indicates to me that limiting access to classified aircraft and other hardware was not a consideration.

And I think all the props are in that position because of Gravity.
 

Users who are viewing this thread

Back