Henschel Hs 293

https://en.wikipedia.org/wiki/Henschel_Hs_293

The Henschel Hs 293 was a World War II German anti-ship guided missile: a radio
controlled glide bomb with a rocket engine slung underneath it. It was designed
by Herbert A. Wagner.

The Hs 293 project was started in 1940, based on the "Gustav Schwartz
Propellerwerke" pure glide bomb that was designed in 1939. The Schwartz design
did not have a terminal guidance system; instead, it used an autopilot to
maintain a straight course. It was intended to be launched from a bomber at
sufficient distance to keep the aircraft out of range of anti-aircraft fire. A
Henschel team, under Dr. Herbert Wagner, developed it the following year by
adding a Walter HWK 109-507 rocket engine underneath, providing 590 kg (1,300
lb) thrust for ten seconds. This allowed the bomb to be used from a lower
altitude and at an increased range. Some examples used the BMW 109-511 of 600 kg
(1,300 lb) thrust.

The weapon consisted of a modified standard 500 kilogram
Sprengbombe-Cylindrisch-class SC 500 "general purpose" bomb with an added
"Kopfring" on the nose for maritime use, to help ensure a relatively
perpendicular axis of impact, with a thin metal shell and a high explosive
charge inside, equipped with a rocket engine beneath the bomb, a pair of
aileron-fitted wings, and the receiving FuG 230 component of the Kehl-Straßburg
MCLOS guidance and control system, shared with the contemporary Fritz X gravity
bomb. The elevator was operated with an electrically powered jackscrew as the
only proportional control, while the ailerons were operated with solenoids.
Remote flight control was provided through the Kehl-Straßburg link, with the Hs
293's control setup having no movable rudder on the ventral tailfin. The rocket
provided for only a short burst of speed making range dependent on the height of
launch. From a height of 1,400 m (4,600 ft) the Hs 293 had a range of about 12
km (7.5 mi; 6.5 nmi).

The Hs 293 was intended to destroy unarmoured ships, unlike the unpowered,
armour-piercing Fritz X, which used the same Kehl-Straßburg system. Five
coloured flares were attached to the rear of the weapon to make it visible at a
distance to the operator. During night operations flashing lights instead of
flares were used.

After the missile was launched, the bomber had to fly in a straight and level
path at a set altitude and speed parallel to the target so as to be able to
maintain a slant line of sight and could not manoeuvre to evade attacking
fighters without aborting the attack.

The Allies put considerable effort into developing devices which jammed the
radio link between Kehl transmitter and Straßburg receiver. Jammers aboard U.S.
Navy destroyer escorts were ineffective at first, as the frequencies selected
for jamming were incorrect. On balance, the probability that a Hs 293 launched
(and seen as responding to operator guidance) would actually strike a target (or
achieve a damage-inflicting near miss) was about the same at Anzio as it was
during Operation Avalanche.

As attacks were taking place at Anzio, the United Kingdom began to deploy its
Type 650 transmitter which employed a different approach to interfering with the
FuG 203/230 radio link, by jamming the Straßburg receiver's intermediate
frequency section, which operated at a 3 MHz frequency and appears to have been
quite successful, especially because the operator did not have to attempt to
find which of the eighteen selected Kehl-Straßburg command frequencies were in
use and then manually tune the jamming transmitter to one of them. The Type 650
automatically defeated the receiver, regardless which radio frequency had been
selected for a missile.

Following several intelligence coups, including a capture of an intact Hs 293 at
Anzio and recovery of important components of the Kehl transmitter from a
crashed Heinkel He 177 on Corsica, the Allies were able to develop far more
effective countermeasures, in time for the invasion of Normandy and Operation
Dragoon. These included AIL's Type MAS jammer, which employed sophisticated
signals to defeat the Kehl transmission and to take over command of the Hs 293,
steering it into the sea via a sequence of right-turn commands. In contrast to
the experience at Anzio, the jammers seemed to have had a major impact on
operations after April 1944, with significant degradation observed in the
probability that a Hs 293 missile could achieve a hit or damage-causing near
miss.


Type
Anti-ship glide bomb

Place of origin
Nazi Germany

Service history

In service
1943- 1944

Used by
Luftwaffe

Wars
World War II

Production history

Manufacturer
Henschel Flugzeug-Werke AG

Produced
1942 - ?

No. built
1,000

Specifications

Mass
1,045 kilograms (2,304 lb)

Length
3.82 metres (12.5 ft)

Width
3.1 metres (10 ft)

Diameter
0.47 metres (1.5 ft)

Warhead
explosive

Warhead weight
295 kilograms (650 lb)

On August 25, 1943, an Hs 293 was used in the first successful attack by a
guided missile, striking the sloop HMS Bideford; however, as the warhead did not
detonate, the damage was minimal. On August 27, the sinking of the British sloop
HMS Egret by a squadron of 18 Dornier Do 217 carrying Hs 293s led to anti-U-boat
patrols in the Bay of Biscay being temporarily suspended. On November 26, an Hs
293 sank the troop transport HMT Rohna killing over 1,000 personnel.

Although designed for use against ships, it was also used in Normandy in early
August 1944 to attack bridges over the Sée and Sélune rivers. One bridge was
slightly damaged for the loss of six of the attacking aircraft. The attack on 7
August 1944 at Pontaubault, performed by Do 217 of III./KG 100, was the first
usage of a standoff missile against a land target ever. On 12 April 1945 Hs 293A
bombs were used once more, against bridges on the Oder, by Do 217 bombers of KG
200.

The Hs 293 was carried on Heinkel He 111, Heinkel He 177, Focke-Wulf Fw 200, and
Dornier Do 217 planes. However, only the He 177 (of I and II.Gruppen/KG 40),
certain variants of the Fw 200 (of III./KG 40) and the Do 217 (of II./KG 100 and
III./KG 100) used the Hs 293 operationally in combat.





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