Already did it a few minutes ago. I took the 1883 item (800 kg GP Bomb), gave it 255 accuracy and set it to upgrade to itself. Equipped 24 P1Ys with 10 each (load limit multiplied by ten as well).
Then I switched out all bomber group pilots for pilots through the veteran reserve system (all NavB in the seventies).
With mixed weather and attack altitude of 15,000 ft I got the results of
1/150
3/150
1/150
3/150
8 hits with 600 bombs released. Even worse than with the missiles.
Remarkably, at times the crews use a few 250 and 60 kg bombs when I forbid them torpedoes and they don't want to use my missile from the second loadout. These 250 and 60 kg bombs hit more often, even with crews which have poor NavB (40s).
Maybe a higher accuracy value means less accuracy, not more?
Don't have the motivation left to test this now.
Missiles
Moderators: wdolson, MOD_War-in-the-Pacific-Admirals-Edition
RE: Missiles
Don't have the motivation left to test this now.
Changed my mind.
Accuracy of GP bomb set to 1. Crews in their 70er skill-wise (NavB).
2 hits among 440 bombs released.
This is ridiculous. I don't see a much of a difference between accuracy 255 and accuracy 1!
RE: Missiles
Run the tests at 6k feet and see what happens. That seems to be a sweet spot for it. 15k is a bit high.
Distant Worlds Fan
'When in doubt...attack!'
'When in doubt...attack!'
RE: Missiles
6k feet is pointless. 40mm Bofors reaches up to 9,800 ft, so 10,000 ft is the minimum altitude.
RE: Missiles
GP bomb accuracy set to 255, 10,000ft altitude, crews with NavB in their 70s, P1Y bombers with each 10 of the "high accuracy" bombs.
5/150
2/150
3/150
That's still only 10/450, about 2%. Vastly inadequate.
In fact, historical tests have shown 0.5% accuracy for dumb bombs under such conditions!
My guided bomb should have about 25% hits after accounting for 25% duds (~Fritz-X statistics).
5/150
2/150
3/150
That's still only 10/450, about 2%. Vastly inadequate.
In fact, historical tests have shown 0.5% accuracy for dumb bombs under such conditions!
My guided bomb should have about 25% hits after accounting for 25% duds (~Fritz-X statistics).
RE: Missiles
Now then, load them onto a dive bomber and try it, I bet the results will be far more accurate.
Distant Worlds Fan
'When in doubt...attack!'
'When in doubt...attack!'
RE: Missiles
I suppose dive bombers will get into range of 40 mm AAA...the point of the exercise is to give the Japanese bombers a chance to score hits after overcoming the CAP without facing the excessive light AAA of the USN.
Guided bombs (the Japanese even had some projects about them) are guided munition technology that Germany could have supplied during 1943 (in fact, such weapons were under development by< 1917!).
Guided bombs (the Japanese even had some projects about them) are guided munition technology that Germany could have supplied during 1943 (in fact, such weapons were under development by< 1917!).
RE: Missiles
Actually, put them on the dive bombers for testing purposes. The reason is that by using different airframes and setting at the same altitude is that you can determine if it is the device settings or the airframe settings that are affecting accuracy. Basically you need a control and an experiment...by using DB or TB airframes as well as the LB airframes you can help determine what is the contributing factor to the low accuracy numbers.
Pilots will have an effect on the result as well, but you don't have as much control over that (IE you can't set the naval bombing skill to all 75 etc).
Pilots will have an effect on the result as well, but you don't have as much control over that (IE you can't set the naval bombing skill to all 75 etc).
Distant Worlds Fan
'When in doubt...attack!'
'When in doubt...attack!'
RE: Missiles
??
Would the aircraft having a air to surface radar help?
Something has to guide the missile.
Equally I would trial heavy bombers, you never know what hidden switches are in there.
??
Would the aircraft having a air to surface radar help?
Something has to guide the missile.
Equally I would trial heavy bombers, you never know what hidden switches are in there.
??
Interdum feror cupidine partium magnarum Europae vincendarum
RE: Missiles
In game, the radar might make a difference. Putting the Fritz-X on G3Ms might help.
As far as real life goes, the Fritz-X was guided via remote control (a lot like flying a remote control airplane), while the JB-2 Loon was also radio guided.
As far as real life goes, the Fritz-X was guided via remote control (a lot like flying a remote control airplane), while the JB-2 Loon was also radio guided.
Distant Worlds Fan
'When in doubt...attack!'
'When in doubt...attack!'
RE: Missiles
Hi. Fritzerini with same specs as Ohka in a Betty. 18.5% hits. Not bad. [:)]
- Attachments
-
- Fritzi Betty.jpg (87.65 KiB) Viewed 104 times
RE: Missiles
And …
Fritzerini PGM on a Ki-21-II Sally. 16.7% hits. Not so good but maybe it was the smoke of burning tankers. [:D][:D]
Fritzerini PGM on a Ki-21-II Sally. 16.7% hits. Not so good but maybe it was the smoke of burning tankers. [:D][:D]
- Attachments
-
- Fritzi Sally.jpg (91.36 KiB) Viewed 103 times
RE: Missiles
1,000 feet attacks exploit that missile attacks are immune to AAA. This means immunity against heavy AAA which they shouldn't have with guided bombs and it distorts the escorts/CAP issue. I'm trying to avoid that. I suppose I couldn't stand this for hundreds of turns, doesn't feel right (= rather gamey).
I wouldn't even like it for Ohka, for Ohka was a glide weapon that required a fine launch altitude for range.
@Shark: More importantly, Ohkas were human-guided and the engine was meant for them.
I'll later check some things. I have a suspicion the engine probably treats AP and GP bombs differently.
The "accuracy" variable of the GP bombs reminds me more of "blast radius" than accuracy, for sure (that would still be redundant to soft rating, of course). The "accuracy" value grows a lot with bomb size.
I wouldn't even like it for Ohka, for Ohka was a glide weapon that required a fine launch altitude for range.
@Shark: More importantly, Ohkas were human-guided and the engine was meant for them.
I'll later check some things. I have a suspicion the engine probably treats AP and GP bombs differently.
The "accuracy" variable of the GP bombs reminds me more of "blast radius" than accuracy, for sure (that would still be redundant to soft rating, of course). The "accuracy" value grows a lot with bomb size.
RE: Missiles
I tested 255 acc SAP bombs on B7A2 Ryusei with 70s crews, 15k feet set altitude (release at 1k to 3k feet).
The results are still underwhelming, not much better than used from D3As early in he war.
I score on average only 3-4 800 kg hits on targets for every Ryusei lost, some pilots decide to kamikaze (I don't like that for low priority targets) and the targets were mere AKs and DDs.
I suppose this level of performance is inadequate against an Air or Surface Combat TF and falls well short of Fritz-X-like performance.
Maybe I'll test next how a torpedo fares if range is increased. Several technologies (torpedo glider, Bombentorpedos with up to 3 km range, torpedoes with guidance, rolling bombs) could justify such a device as not too gamey.
I suppose I'm not going to be able to build a non-gamey model of the Fritz-X in WITPAE.
The results are still underwhelming, not much better than used from D3As early in he war.
I score on average only 3-4 800 kg hits on targets for every Ryusei lost, some pilots decide to kamikaze (I don't like that for low priority targets) and the targets were mere AKs and DDs.
I suppose this level of performance is inadequate against an Air or Surface Combat TF and falls well short of Fritz-X-like performance.
Maybe I'll test next how a torpedo fares if range is increased. Several technologies (torpedo glider, Bombentorpedos with up to 3 km range, torpedoes with guidance, rolling bombs) could justify such a device as not too gamey.
I suppose I'm not going to be able to build a non-gamey model of the Fritz-X in WITPAE.
RE: Missiles
Fritz X need to be launched at 20000ft to have the claimed penetrating power. The range was not much more than 1km...
There were many failures despite the high profile successes.
There should also simultaneous release limits, i don't have data for Fritz but 18 Hs293 was the maximum number in air due to radio frequency limitations.
There were many failures despite the high profile successes.
There should also simultaneous release limits, i don't have data for Fritz but 18 Hs293 was the maximum number in air due to radio frequency limitations.
RE: Missiles
Actually, Fritz-X was found to work fine at altitudes 4,000 to 9,000 metres. That's about 13,000 to 27,000 ft and operational drops from up to 8,000 m. Only ships such as King George V class did really necessitate more than 3/4 of the maximum penetration possible. Fritz-X had air brakes because of controllability issues at very high speeds, so it did not need the full maximum drop altitude for maximum impact velocity.
Command limit for Fritz-X was 18 at a time (S 203 "Kehl"), but they did at times fly radio recce missions in advance to see which channels are not jammed.
CEP was 7 m with all non-malfunctioning bombs impacting in a radius of 13 m (40 test drops from 4,000 to 7,000 m).
Fritz X:
22 missions
108 PC 1400 X were onboard
60 dropped on target
44 functioned
16 malfunctioned
of the 44 which functioned:
14 direct hits
7 effective near misses (effect expected because of underwater explosion similar to a mine hit)
13 misses
10 times impact not observed
14/108 ~ 13%
21/108 ~ 19%
Improvements of dud rate were to be expected if the munition had been in use more often, for a longer time. It did obviously still have teething problems.
A hit on BB Littorio penetrated from top to bottom, detonated below and caused a flooding by 900 tons of water. Warspite took in 5,000 tons after three hits. Such floodings mean that even without secondary effects (fires, explosions), a battleship couldn't take more than about 5-6 such hits without sinking (~one slightly understrength bomber group attack).
Other hits demonstrated that gunners could aim for and take out main ammunition magazines onboard of battleships and cruisers and sink even battleships with 1-2 hits this way.
source: Almost all from
"Die deutsche Luftfahrt"
Volume 10: "Flugkörper und Lenkraketen",
first edition (new edition is overdue)
Command limit for Fritz-X was 18 at a time (S 203 "Kehl"), but they did at times fly radio recce missions in advance to see which channels are not jammed.
CEP was 7 m with all non-malfunctioning bombs impacting in a radius of 13 m (40 test drops from 4,000 to 7,000 m).
Fritz X:
22 missions
108 PC 1400 X were onboard
60 dropped on target
44 functioned
16 malfunctioned
of the 44 which functioned:
14 direct hits
7 effective near misses (effect expected because of underwater explosion similar to a mine hit)
13 misses
10 times impact not observed
14/108 ~ 13%
21/108 ~ 19%
Improvements of dud rate were to be expected if the munition had been in use more often, for a longer time. It did obviously still have teething problems.
A hit on BB Littorio penetrated from top to bottom, detonated below and caused a flooding by 900 tons of water. Warspite took in 5,000 tons after three hits. Such floodings mean that even without secondary effects (fires, explosions), a battleship couldn't take more than about 5-6 such hits without sinking (~one slightly understrength bomber group attack).
Other hits demonstrated that gunners could aim for and take out main ammunition magazines onboard of battleships and cruisers and sink even battleships with 1-2 hits this way.
source: Almost all from
"Die deutsche Luftfahrt"
Volume 10: "Flugkörper und Lenkraketen",
first edition (new edition is overdue)
RE: Missiles
ORIGINAL: JSG
1,000 feet attacks exploit that missile attacks are immune to AAA. This means immunity against heavy AAA which they shouldn't have with guided bombs and it distorts the escorts/CAP issue. I'm trying to avoid that. I suppose I couldn't stand this for hundreds of turns, doesn't feel right (= rather gamey).
I wouldn't even like it for Ohka, for Ohka was a glide weapon that required a fine launch altitude for range.
@Shark: More importantly, Ohkas were human-guided and the engine was meant for them.
I'll later check some things. I have a suspicion the engine probably treats AP and GP bombs differently.
The "accuracy" variable of the GP bombs reminds me more of "blast radius" than accuracy, for sure (that would still be redundant to soft rating, of course). The "accuracy" value grows a lot with bomb size.
Yep, Okha was most definitely human guided, and as such was just as susceptible to the limits of any aircraft. IE the pilot could be incapacitated.
In all truth, the Fritz X was a glide bomb (not at all unlike glide bombs in use today, though the guidance system was more primitive). So I'm wondering how Fritz X works as a bomb with higher accuracy as opposed to being treated more like an Okha?
Distant Worlds Fan
'When in doubt...attack!'
'When in doubt...attack!'
RE: Missiles
As a "Fritz" type was, as you say, more a PGM thasn an ASM I think your premise works OK.
I've been trying to get something to fire from outside of the target hex, I'll be happy with the adjaecent hex but lots of trials didnt work.
Even though you can set the range as 200 miles + they only work within the same hex, reasonable as you cant set another hex as the target.
This might be OK for an Okha but not for the "Loon" types with longer range unless you make it a kamikaze type aircraft, not sure this setting works for the Allies.
I've been trying to get something to fire from outside of the target hex, I'll be happy with the adjaecent hex but lots of trials didnt work.
Even though you can set the range as 200 miles + they only work within the same hex, reasonable as you cant set another hex as the target.
This might be OK for an Okha but not for the "Loon" types with longer range unless you make it a kamikaze type aircraft, not sure this setting works for the Allies.
Interdum feror cupidine partium magnarum Europae vincendarum
-
el cid again
- Posts: 16980
- Joined: Mon Oct 10, 2005 4:40 pm
RE: Missiles
I too am trying to get something to work outside the hex - particularly in view of the USAAF and USN programs based on the V-1.
aka V-1
Republic-Ford JB-2From Wikipedia, the free encyclopediaJump to: navigation, search JB-2/KGW Loon
Republic/Ford JB-2 at the National Museum of the United States Air Force.
Type Cruise missile
Place of origin United States
Service history
In service 1945-1950
Used by United States Army Air Forces
United States Air Force
United States Navy
Production history
Manufacturer Republic Aircraft
Willys-Overland
Ford Motor Company
Produced 1944-1945
Number built 1,391
Specifications
Weight 5,000 pounds (2,300 kg)
Length 27 feet 1 inch (8.26 m)
Diameter 34 inches (860 mm)
--------------------------------------------------------------------------------
Warhead High explosive
Warhead weight 2,000 pounds (910 kg)
--------------------------------------------------------------------------------
Engine Ford PJ31 pulsejet
660 lbf (2.9 kN)
Wingspan 17 feet 8 inches (5.38 m)
Operational
range 150 miles (240 km)
Speed 425 miles per hour (684 km/h)
Guidance
system Radio command
Accuracy 0.25 miles (0.40 km) at 100 miles (160 km)
JB-2 Loon being inspected by USAAF personnel at Wendover AAF, 1944.
JB-2 being air launched for flight test by B-17 bomber during testing of weapon at Eglin Field, 1944
In flight after air launch, 1944
Ground preparation prior to air launch, 1944
JB-2 Loon being prepared for a test launch at Holloman AFB about 1948.
A Loon being fired from USS Cusk in 1951The Republic-Ford JB-2 Loon was a United States copy of the German V-1 flying bomb. Developed in 1944, and planned to be used in the United States invasion of Japan (Operation Downfall), the JB-2 was never used in combat. It was the most successful of the United States Army Air Forces Jet Bomb (JB) projects (JB-1 through JB-10) during World War II. Postwar, the JB-2 played a significant role in the development of more advanced surface-to-surface tactical missile systems such as the MGM-1 Matador and later MGM-13 Mace.
Contents [hide]
1 Wartime development
2 Postwar testing
3 JB-2 survivors
4 See also
5 References
6 External links
[edit] Wartime developmentThe United States had known of the existence of a new German secret weapon since 22 August 1942 when a Danish Naval Officer discovered an early test version of the V-1 that had crashed on the island of Bornholm; in the Baltic Sea between Germany and Sweden. A photograph and a detailed sketch of the V-1 test unit V83 was sent to Britain. This led to months of intelligence-gathering and intelligence-sifting which traced the weapon to Peenemünde, on Germany's Baltic Coast, the top-secret German missile test and development site.[1]
As more intelligence data was obtained though aerial photography and sources inside Germany, it was decided in 1943 for the United States to develop a jet-powered bomb as well. The United States Army Air Forces gave Northrop Aircraft a contract in July 1944 to develop the JB-1 (Jet Bomb 1) turbojet-powered flying bomb under project MX-543. Northrop designed a flying-wing aircraft with two General Electric B1 turbojets in the center section, and two 900 kg (2000 lb) general purpose bombs in enclosed "bomb containers" in the wing roots. To test the aerodynamics of the design, one JB-1 was completed as a manned unpowered glider, which was first flown in August 1944.[1]
However, in July 1944, three weeks after German V-1 "Buzz Bombs" first struck England on June 12 and 13, American engineers at Wright Field, fired a working copy of the German Argus As 014 pulse-jet engine, "reverse-engineered" from crashed German V-1s that were brought to the United States from England for analysis. The reverse engineering provided the design of America's first mass-produced guided missile, the JB-2.[2]
By 8 September, the first of thirteen complete JB-2s, reverse engineered from the material received at Wright Field in July was assembled at Republic Aviation. The United States JB-2 was different from the German V-1 in only the smallest of dimensions. The wing span was only 2½ inches wider and the length was extended less than 2 feet (0.61 m). The difference gave the JB-2 60.7 square feet of wing area versus 55 for the V-1.[1]
This was the first unmanned guided missile in America's arsenal. The first launch of a JB-2 took place at Eglin Army Air Field in Florida by the 1st Proving Ground Group on 12 October 1944. In addition to the Eglin group, a detachment of the Special Weapons Branch, Wright Field, Ohio, arrived at Wendover Field, Utah, in 1944 with the mission of evaluating captured & experimental systems, including the JB-2. Testing was from a launch structure just south of Wendover's technical site. The launch area is visible in aerial imagery ( WikiMiniAtlas
40°41′53″N 114°02′29″W / 40.69806°N 114.04139°W / 40.69806; -114.04139). Parts of crashed JB-2s are occasionally found by Wendover Airport personnel.[1]
In December 1944, the first JB-1 was ready for launch. The missile was launched by a rocket-propelled sled along a 150 m (500 ft) long track, but seconds after release the JB-1 pitched up into a stall and crashed. This was caused by an incorrectly calculated elevon setting for take-off, but the JB-1 program was subsequently stopped, mainly because the performance and reliability of the GE B1 turbojet engines were far below expectations. In addition, the cost to produce the Ford copy of the Argus pulse-jet engine of the JB-2 was much less than the GE turbojets. Subsequently work proceeded on the JB-2 for final development and production.[1][3]
An initial production order was 1,000 units, with subsequent production of 1,000 per month. That figure was not anticipated to be attainable until April 1945. Republic had its production lines at capacity for producing P-47 Thunderbolts, so it sub-contracted airframe manufacturing to Willys-Overland. Ford Motor Co built the engine, designated IJ-15-1, which was a copy of the V-1's 900-lb. thrust Argus-Schmidt pulse-jet. Guidance and flight controls were manufactured by Jack and Heintz Company of Cleveland, Ohio, and Monsanto took on the task of designing a better launching system, with Northrop supplying the launch sleds. Production delivery began in January 1945.[1]
An envisioned 75,000 JB-2s were planned for production. A USAAF launching squadron was formed in anticipation for using the weapons both against Nazi Germany and Japan. However, the end of the European War in May 1945 meant a reduction of the number of JB-2s to be produced, but not the end of the program. Army commanders in Europe had dismissed it as a weapon against Nazi Germany, as the strategic bombing concept was implemented and by 1945 the number of strategic targets in Germany was becoming limited. However, the JB-2 was envisioned as a weapon to attack Japan. A 180-day massive bombardment of the Japanese Home Islands was being planned prior to the amphibious landing "by the most powerful and sustained pre-invasion bombardment of the war". Included in the assault were the usual naval bombardment and air strikes augmented by rocket-firing aircraft and JB-2s.[1]
A navalized version, designated KGW-1, was planned to be used against Japan from LSTs (Landing Ship, Tank) as well as escort carriers (CVEs). In addition, launches from PB4Y-2 Privateers were foreseen and techniques developed. The official U.S. Air Force Fact Sheet on the JB-2 states just before the end of the war, an aircraft carrier en route to the Pacific took on a load of JB-2s for possible use in the planned invasion of the Japanese home islands, however the name of the carrier has never been identified. In addition, according to one Eglin AFB history, an unidentified USAAF unit in the Philippines was preparing to launch JB-2s against Japan.[1] The war's end led to the cancellation of Operation Downfall and the production of JB-2s was terminated on 15 September. A total of 1,391 units were manufactured.[1]
[edit] Postwar testingThe U.S. Army Air Force continued development of the JB-2 as Project MX-544, with two versions — one with preset internal guidance and another with radar control. Several launch platforms were developed, including permanent and portable ramps, and mobile launching from beneath the wings of Boeing B-17G or Boeing B-29 bombers, much as the Heinkel He 111H-22 had actually done late in the war for the Luftwaffe. Testing continued from 1944 to 1947 at Eglin to improve launch and guidance.
The U.S. Navy's version, the KGW-1, later redesignated LTV-N-2, was developed to be carried on the aft deck of submarines in watertight containers. The first submarine to employ them was the SS-348 Cusk which successfully launched its first Loon on February 12, 1947, off Point Mugu, California.
After the United States Air Force became a fully independent arm of the National Military Establishment 18 September 1947, research continued with the development of unmanned aircraft and pilotless bombers, including the already available JB-2.
The USAF Air Materiel Command reactivated the JB-2 as Project EO-727-12 on 23 April 1948, at Holloman AFB, New Mexico, the former Alamogordo Army Air Field. The JB-2 was used for development of missile guidance control and seeker systems, testing of telemetering and optical tracking facilities, and as a target for new surface-to-air and air-to-air missiles (ironically fulfilling the former V1's covername, Flakzielgerät — anti-aircraft target device). The JB-2 project used the North American Aviation NATIV (North American Test Instrument Vehicle) Blockhouse and two launch ramps at Holloman: a 400 ft (120 m), two-rail ramp on a 3° earth-filled slope, and a 40 ft (12 m) trailer ramp. The 40-foot trailer ramp was the first step toward a system which would eventually be adapted for the forthcoming Martin MGM-1 Matador, first operational surface-to-surface cruise missile built by the United States. The program at Holloman was terminated on 10 January 1949 after successful development of a radio guidance and control system that could control and even skid-land a JB-2 under the control of an airborne or ground transmitter.[1]
The 1st Experimental Guided Missiles Group used JB-2s in a series of tests in the late 1940s at Eglin Air Force Base, Florida. In the spring of 1949, the 3200th Proof Test Group tested launching JB-2s from the under the wings of B-36 Peacemaker bombers at Eglin AFB.[4] About a year later, JB-2s were tested as aerial targets for experimental infrared gunsights at Eglin.[5]
In the summer of 1992, military crews uncovered the well-preserved wreckage of a JB-2 at a site on an Air Force-owned section of Santa Rosa Island. Most crash sites on the barrier island were little more than flaky rust, but after the find, officials were planning further searches.[6]
[edit] JB-2 survivorsNational Museum of the United States Air Force, Dayton, Ohio
U.S. Air Force Armament Museum, Eglin AFB, Florida
Evergreen Aviation & Space Museum, McMinnville, Oregon
(Engine only, operational) Planes of Fame air museum, Chino, California[1]
A JB-2 is on open-air display at the Museum of Alaska Transportation and Industry in Wasilla, Alaska.
Museum of Transport and Technology (MOTAT), Auckland, New Zealand
Hill Aerospace Museum, Hill AFB, Utah has an original JB-2, "Wendover Willie" [2]
Point Mugu Missile Park, on open-air display at Naval Air Station Point Mugu, California.
Cradle of Aviation Museum, Garden City, New York.
National Air and Space Museum at the Steven F. Udvar-Hazy Center, Washington, D.C.
Milford Township Park at Milford, IL [7].
A JB-2 is on open-air display at the American Legion post in Wheaton, Minnesota.
aka V-1
Republic-Ford JB-2From Wikipedia, the free encyclopediaJump to: navigation, search JB-2/KGW Loon
Republic/Ford JB-2 at the National Museum of the United States Air Force.
Type Cruise missile
Place of origin United States
Service history
In service 1945-1950
Used by United States Army Air Forces
United States Air Force
United States Navy
Production history
Manufacturer Republic Aircraft
Willys-Overland
Ford Motor Company
Produced 1944-1945
Number built 1,391
Specifications
Weight 5,000 pounds (2,300 kg)
Length 27 feet 1 inch (8.26 m)
Diameter 34 inches (860 mm)
--------------------------------------------------------------------------------
Warhead High explosive
Warhead weight 2,000 pounds (910 kg)
--------------------------------------------------------------------------------
Engine Ford PJ31 pulsejet
660 lbf (2.9 kN)
Wingspan 17 feet 8 inches (5.38 m)
Operational
range 150 miles (240 km)
Speed 425 miles per hour (684 km/h)
Guidance
system Radio command
Accuracy 0.25 miles (0.40 km) at 100 miles (160 km)
JB-2 Loon being inspected by USAAF personnel at Wendover AAF, 1944.
JB-2 being air launched for flight test by B-17 bomber during testing of weapon at Eglin Field, 1944
In flight after air launch, 1944
Ground preparation prior to air launch, 1944
JB-2 Loon being prepared for a test launch at Holloman AFB about 1948.
A Loon being fired from USS Cusk in 1951The Republic-Ford JB-2 Loon was a United States copy of the German V-1 flying bomb. Developed in 1944, and planned to be used in the United States invasion of Japan (Operation Downfall), the JB-2 was never used in combat. It was the most successful of the United States Army Air Forces Jet Bomb (JB) projects (JB-1 through JB-10) during World War II. Postwar, the JB-2 played a significant role in the development of more advanced surface-to-surface tactical missile systems such as the MGM-1 Matador and later MGM-13 Mace.
Contents [hide]
1 Wartime development
2 Postwar testing
3 JB-2 survivors
4 See also
5 References
6 External links
[edit] Wartime developmentThe United States had known of the existence of a new German secret weapon since 22 August 1942 when a Danish Naval Officer discovered an early test version of the V-1 that had crashed on the island of Bornholm; in the Baltic Sea between Germany and Sweden. A photograph and a detailed sketch of the V-1 test unit V83 was sent to Britain. This led to months of intelligence-gathering and intelligence-sifting which traced the weapon to Peenemünde, on Germany's Baltic Coast, the top-secret German missile test and development site.[1]
As more intelligence data was obtained though aerial photography and sources inside Germany, it was decided in 1943 for the United States to develop a jet-powered bomb as well. The United States Army Air Forces gave Northrop Aircraft a contract in July 1944 to develop the JB-1 (Jet Bomb 1) turbojet-powered flying bomb under project MX-543. Northrop designed a flying-wing aircraft with two General Electric B1 turbojets in the center section, and two 900 kg (2000 lb) general purpose bombs in enclosed "bomb containers" in the wing roots. To test the aerodynamics of the design, one JB-1 was completed as a manned unpowered glider, which was first flown in August 1944.[1]
However, in July 1944, three weeks after German V-1 "Buzz Bombs" first struck England on June 12 and 13, American engineers at Wright Field, fired a working copy of the German Argus As 014 pulse-jet engine, "reverse-engineered" from crashed German V-1s that were brought to the United States from England for analysis. The reverse engineering provided the design of America's first mass-produced guided missile, the JB-2.[2]
By 8 September, the first of thirteen complete JB-2s, reverse engineered from the material received at Wright Field in July was assembled at Republic Aviation. The United States JB-2 was different from the German V-1 in only the smallest of dimensions. The wing span was only 2½ inches wider and the length was extended less than 2 feet (0.61 m). The difference gave the JB-2 60.7 square feet of wing area versus 55 for the V-1.[1]
This was the first unmanned guided missile in America's arsenal. The first launch of a JB-2 took place at Eglin Army Air Field in Florida by the 1st Proving Ground Group on 12 October 1944. In addition to the Eglin group, a detachment of the Special Weapons Branch, Wright Field, Ohio, arrived at Wendover Field, Utah, in 1944 with the mission of evaluating captured & experimental systems, including the JB-2. Testing was from a launch structure just south of Wendover's technical site. The launch area is visible in aerial imagery ( WikiMiniAtlas
40°41′53″N 114°02′29″W / 40.69806°N 114.04139°W / 40.69806; -114.04139). Parts of crashed JB-2s are occasionally found by Wendover Airport personnel.[1]
In December 1944, the first JB-1 was ready for launch. The missile was launched by a rocket-propelled sled along a 150 m (500 ft) long track, but seconds after release the JB-1 pitched up into a stall and crashed. This was caused by an incorrectly calculated elevon setting for take-off, but the JB-1 program was subsequently stopped, mainly because the performance and reliability of the GE B1 turbojet engines were far below expectations. In addition, the cost to produce the Ford copy of the Argus pulse-jet engine of the JB-2 was much less than the GE turbojets. Subsequently work proceeded on the JB-2 for final development and production.[1][3]
An initial production order was 1,000 units, with subsequent production of 1,000 per month. That figure was not anticipated to be attainable until April 1945. Republic had its production lines at capacity for producing P-47 Thunderbolts, so it sub-contracted airframe manufacturing to Willys-Overland. Ford Motor Co built the engine, designated IJ-15-1, which was a copy of the V-1's 900-lb. thrust Argus-Schmidt pulse-jet. Guidance and flight controls were manufactured by Jack and Heintz Company of Cleveland, Ohio, and Monsanto took on the task of designing a better launching system, with Northrop supplying the launch sleds. Production delivery began in January 1945.[1]
An envisioned 75,000 JB-2s were planned for production. A USAAF launching squadron was formed in anticipation for using the weapons both against Nazi Germany and Japan. However, the end of the European War in May 1945 meant a reduction of the number of JB-2s to be produced, but not the end of the program. Army commanders in Europe had dismissed it as a weapon against Nazi Germany, as the strategic bombing concept was implemented and by 1945 the number of strategic targets in Germany was becoming limited. However, the JB-2 was envisioned as a weapon to attack Japan. A 180-day massive bombardment of the Japanese Home Islands was being planned prior to the amphibious landing "by the most powerful and sustained pre-invasion bombardment of the war". Included in the assault were the usual naval bombardment and air strikes augmented by rocket-firing aircraft and JB-2s.[1]
A navalized version, designated KGW-1, was planned to be used against Japan from LSTs (Landing Ship, Tank) as well as escort carriers (CVEs). In addition, launches from PB4Y-2 Privateers were foreseen and techniques developed. The official U.S. Air Force Fact Sheet on the JB-2 states just before the end of the war, an aircraft carrier en route to the Pacific took on a load of JB-2s for possible use in the planned invasion of the Japanese home islands, however the name of the carrier has never been identified. In addition, according to one Eglin AFB history, an unidentified USAAF unit in the Philippines was preparing to launch JB-2s against Japan.[1] The war's end led to the cancellation of Operation Downfall and the production of JB-2s was terminated on 15 September. A total of 1,391 units were manufactured.[1]
[edit] Postwar testingThe U.S. Army Air Force continued development of the JB-2 as Project MX-544, with two versions — one with preset internal guidance and another with radar control. Several launch platforms were developed, including permanent and portable ramps, and mobile launching from beneath the wings of Boeing B-17G or Boeing B-29 bombers, much as the Heinkel He 111H-22 had actually done late in the war for the Luftwaffe. Testing continued from 1944 to 1947 at Eglin to improve launch and guidance.
The U.S. Navy's version, the KGW-1, later redesignated LTV-N-2, was developed to be carried on the aft deck of submarines in watertight containers. The first submarine to employ them was the SS-348 Cusk which successfully launched its first Loon on February 12, 1947, off Point Mugu, California.
After the United States Air Force became a fully independent arm of the National Military Establishment 18 September 1947, research continued with the development of unmanned aircraft and pilotless bombers, including the already available JB-2.
The USAF Air Materiel Command reactivated the JB-2 as Project EO-727-12 on 23 April 1948, at Holloman AFB, New Mexico, the former Alamogordo Army Air Field. The JB-2 was used for development of missile guidance control and seeker systems, testing of telemetering and optical tracking facilities, and as a target for new surface-to-air and air-to-air missiles (ironically fulfilling the former V1's covername, Flakzielgerät — anti-aircraft target device). The JB-2 project used the North American Aviation NATIV (North American Test Instrument Vehicle) Blockhouse and two launch ramps at Holloman: a 400 ft (120 m), two-rail ramp on a 3° earth-filled slope, and a 40 ft (12 m) trailer ramp. The 40-foot trailer ramp was the first step toward a system which would eventually be adapted for the forthcoming Martin MGM-1 Matador, first operational surface-to-surface cruise missile built by the United States. The program at Holloman was terminated on 10 January 1949 after successful development of a radio guidance and control system that could control and even skid-land a JB-2 under the control of an airborne or ground transmitter.[1]
The 1st Experimental Guided Missiles Group used JB-2s in a series of tests in the late 1940s at Eglin Air Force Base, Florida. In the spring of 1949, the 3200th Proof Test Group tested launching JB-2s from the under the wings of B-36 Peacemaker bombers at Eglin AFB.[4] About a year later, JB-2s were tested as aerial targets for experimental infrared gunsights at Eglin.[5]
In the summer of 1992, military crews uncovered the well-preserved wreckage of a JB-2 at a site on an Air Force-owned section of Santa Rosa Island. Most crash sites on the barrier island were little more than flaky rust, but after the find, officials were planning further searches.[6]
[edit] JB-2 survivorsNational Museum of the United States Air Force, Dayton, Ohio
U.S. Air Force Armament Museum, Eglin AFB, Florida
Evergreen Aviation & Space Museum, McMinnville, Oregon
(Engine only, operational) Planes of Fame air museum, Chino, California[1]
A JB-2 is on open-air display at the Museum of Alaska Transportation and Industry in Wasilla, Alaska.
Museum of Transport and Technology (MOTAT), Auckland, New Zealand
Hill Aerospace Museum, Hill AFB, Utah has an original JB-2, "Wendover Willie" [2]
Point Mugu Missile Park, on open-air display at Naval Air Station Point Mugu, California.
Cradle of Aviation Museum, Garden City, New York.
National Air and Space Museum at the Steven F. Udvar-Hazy Center, Washington, D.C.
Milford Township Park at Milford, IL [7].
A JB-2 is on open-air display at the American Legion post in Wheaton, Minnesota.
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el cid again
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RE: Missiles
While an Okha was human guided, Japan had mastered R/C technology for aircraft and had R/C aircraft as targets well before the war.
During the war it got a good deal farther than the US did in terms of missile guidance [The Bumblebee program took until the 1950s
to produce test vehicles and was still unreliable in the early 1960s - and it barely got past definition during WWII]. Admittedly the
best systems were based on German technology - so was our first mass produced missile system (in spite of many USAAF designs
in competition to be first). There is no reason an Okha might not be designed for pilotless flight - and I won't use them except on that
assumption - because (like Adm Yamamoto) I oppose suicide tactics on military efficiency grounds alone. They are still subject to
countermeasures - as is Fritz X - the radio can be jammed - and the control or launch aircraft can be shot down. In game terms,
we cannot tell the actual guidance system - it simply doesn't matter. We are limited to things like range, and effect, etc. Fritz X was
definitely a fine idea and was either the foundation or the inspiration for many weapons since.
During the war it got a good deal farther than the US did in terms of missile guidance [The Bumblebee program took until the 1950s
to produce test vehicles and was still unreliable in the early 1960s - and it barely got past definition during WWII]. Admittedly the
best systems were based on German technology - so was our first mass produced missile system (in spite of many USAAF designs
in competition to be first). There is no reason an Okha might not be designed for pilotless flight - and I won't use them except on that
assumption - because (like Adm Yamamoto) I oppose suicide tactics on military efficiency grounds alone. They are still subject to
countermeasures - as is Fritz X - the radio can be jammed - and the control or launch aircraft can be shot down. In game terms,
we cannot tell the actual guidance system - it simply doesn't matter. We are limited to things like range, and effect, etc. Fritz X was
definitely a fine idea and was either the foundation or the inspiration for many weapons since.
ORIGINAL: Shark7
ORIGINAL: JSG
1,000 feet attacks exploit that missile attacks are immune to AAA. This means immunity against heavy AAA which they shouldn't have with guided bombs and it distorts the escorts/CAP issue. I'm trying to avoid that. I suppose I couldn't stand this for hundreds of turns, doesn't feel right (= rather gamey).
I wouldn't even like it for Ohka, for Ohka was a glide weapon that required a fine launch altitude for range.
@Shark: More importantly, Ohkas were human-guided and the engine was meant for them.
I'll later check some things. I have a suspicion the engine probably treats AP and GP bombs differently.
The "accuracy" variable of the GP bombs reminds me more of "blast radius" than accuracy, for sure (that would still be redundant to soft rating, of course). The "accuracy" value grows a lot with bomb size.
Yep, Okha was most definitely human guided, and as such was just as susceptible to the limits of any aircraft. IE the pilot could be incapacitated.
In all truth, the Fritz X was a glide bomb (not at all unlike glide bombs in use today, though the guidance system was more primitive). So I'm wondering how Fritz X works as a bomb with higher accuracy as opposed to being treated more like an Okha?