The R4/M Orkan wonder weapon, 1945

I´ve written sometimes that the R4/M Orkan was a bomber-killer.
Now I want to present this most potent wonder weapon of all:

German engineers tried to build a useful air-to-ground rocket in the 1930´s. They tried it with spin-stabilized rockets launched
out of a tube. They were most of the time unsuccessful, because the precision and drag problem wasn´t solved.
In 1941, the soviets began to use their RS series fin-stabilized rockets in air-to-ground role (for example, RS82) against the
german army. In germany were tests with spin-stabilized rockets continued until a giant 100mm RZ100 rocket destroyed a
Me210 fuselage during one test shot. (It was fired from, not on the fuselage!).

In 1942, the threat by well-protected B-17F bombers called for a new weapon.
because nothing else was available, WGr21 were used to disrupt the B-17F "combat box" formations from 1943 on.
That was a big and primitive 210mm rocket launched out of a tube and originally designed for ground-to-ground combat.
Its drag was so big that fighter carrying two or four of them had a big problem with the escort fighters.
Further was its precision bad (no proximity fuse) and its 40,8kg warhead by far oversized for its purpose.

At this time fritz Heber (who also built the famous MG-synchronization in 1915 as mechanician for Focker) invented a simple rocket with a propellant chemical (Diglykol) that was in use since many years. Immidiately, 20.000 rockets were ordered, and until war´s end 10.000 or 12.000 built and delivered (Nowarra gives both numbers on one page).

It was tested on Me262A-1a by the infamous elite unit JV44 and contributed a lot to the fame of the JV44 and the Me262A-1a.
Around 60 Me262A-1a recieved each 14 R4M under each outer wing, and the Mk108 gunsight was used for this weapon, too, because of the similar ballistics. In just one sortie, 25 B-17G were killed without losses with the R4M (out of 425). But "conventional" fighters like the Fw190 had also stunning success with this weapon; a group of 24 Fw190 killed without losses 40! B-17G during a strong bomber raid in april, 1945.

Overall, Nowarra (and other authors) wrote that around 500! enemy planes were destroyed
(by just around 10.000 rockets; that´s a ratio of at least around one per sortie because each plane had just 24 rockets!)

R 4/M : R=Rakete, 4=4kg weight, M=Minenkopf (mine warhead)
One hit was usually enough for destroying a B-17G or B-24J.

My comment:
A well-known propellant, a simple fin-stabilization, an old contact fuze, simple ballistics, simple idea, extreme effect.
Sometimes I believe that somebody or something was working hard for protecting the 8th AF against this simple innovation.
Against jet planes were faster rockets necessary than this, but it was in WW2 such a potent bomber-killer that I have to say:
4- and 6-engine-bombers were´nt able to survive against a state-of-the art defense in 1940-1945.
This simple small rocket would have killed all such bombers with ease, even advanced designs like the B-29, Ta400, He177...
The irritating fact is just that it didn´t happen.
Well, after WW2, unguided rockets became the main anti-bomber weapon of US fighters. Some of these fighters didn´t use any
other weapons than HVAR rockets (Lockheed F-94 Starfire, for example).
Invented in 1942, 1943 or early 1944, the R4M would have stopped the 8th Air Force daylight bombing campaign with 100% probability!
I´m just not sure how effective this weapon was against smaller bombers like B-26 and B-25, but I believe that fast and maneuverable
bombers like Mosquito, A-26 and A-20 would have been poor targets for this weapon.

	R4/M Orkan
diameter	5,4cm
length, folded fins	approx. 71cm
propellant	Diglykol
warhead	500g Hexogen
range (shooting distance)	1.500-1.800m
weigth	4kg
max. speed	900km/h
production number	10.000-12.000
fuze	AzRz 2 contact fuze
mode	air-to-air, unguided
inventor	Fritz Heber
operational	at latest march, 1945

the R4/M Orkan and Panzerblitz II(?) (bigger HEAT warhead)

My best sources:
"Die deutsche Luftrüstung 1933-1945" by Heinz J. Nowarra and Luftwaffe Resource Group

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