fire-control power, leaving all guns in local control without any blind-fire capability. Unsurprisingly, later attacks were not seen until the aircraft opened fire and passed over the ship. The incident was blamed on an overzealous fighter director, who ignored the proximity of the picket destroyer, and also on the reluctance of the destroyer to take immediate aggressive AA action in the face of the Control Green order.
A heavy enough strafing gun could kill a ship. During the Second World War the United States mounted an automatic 75mm cannon on board some bombers, notably the B-25 (which the Marines operated as the PBJ).34 This weapon sank at least a few ships.
Rocket attack might be considered the most extreme form of strafing. Rockets offered a good chance of hitting without subjecting an aircraft to the stress of dive or glide bombing. Both the United States and the United Kingdom deployed anti-ship rockets during the Second World War. For example, by late in the war Coastal Command Beaufighters, which attacked German convoys off the European coast, were armed both with rockets and with torpedoes. By about the same time many US fighters and attack aircraft were armed with rockets. Rockets offered the sort of accuracy usually associated with dive bombing, without the requirement for structural strength (to pull out of the dive) or the dive brakes associated with that kind of attack. They could also be delivered from a greater stand-off distance. On the other hand, they did not offer the sort of warhead weight a dive bomber could deliver. The US Navy sometimes claimed that the 5in Mighty Mouse rockets a fighter could deliver gave it the punch of a destroyer’s broadside. By 1944 there was also a much more powerful 11.75in rocket, Tiny Tim.
Guided Weapons
Towards the end of August 1943 the Germans introduced guided weapons which they hoped could be launched by a bomber effectively out of anti-aircraft range: the FX 1400 armour-piercing bomb and the Hs 293 rocket-boosted glide missile. FX 1400 was a guided armour-piercing bomb intended to attack capital ships and cruisers.35 Both weapons were command-controlled, hence could be considered standoff weapons to be fired outside defensive range (Hs 293 was within extreme anti-aircraft range). Guidance was simple. The controller monitored the weapon by focussing on a flare in its tail. He tried to keep it moving in the same line as the bomber. To this extent the weapons could be seen as high-altitude bombs whose flight could be corrected for windage. To some extent the bomber could manoeuvre (like a dive bomber) to deal with target manoeuvres.
The Hs 293 was intended more to attack merchant ships and unarmoured warships. It had a 500kg bomb integrated into its airframe.36 Radio control was exerted on its ailerons and elevators; there was no means of automatic height-keeping. The missile had a gyro autopilot. Because it was a small aircraft, Hs 293 could manoeuvre to some extent after being launched. A bomber typically carried two Hs-293 underwing. As of 1943 two modes of attack had been seen. In one, the bomber approached to within 3 to 5 miles of the target at a height of 3000–5000ft. Once the glider flew out satisfactorily, its controller turned it onto the line of sight to the target, the aircraft continuing on a steady course. The alternative was for the aircraft to approach in a conventional level bombing run at a similar altitude, then launch the glider when 3 to 4 miles from the target. When 3000–4000 yds from the target the control aircraft turned away, directing the missile down onto the target. During the Italian landings attacks were generally from the starboard side (presumably from ahead, as the aimer was on the starboard side of the aircraft and so kept the target to port).
FX 1400 (‘Fritz-X’) was a guided AP bomb. It offered the precision of dive-bombing without exposing the attacker to heavy close-range anti-aircraft fire, which the Germans predicted would ultimately make dive bombing impractical. Moreover, the bomb could be dropped from such a height that it would accelerate sufficiently to penetrate thick deck armour. This type of bomb sank the Italian battleship Roma. Note that successful conventional dive bombing with 1600lb AP bombs achieved the same sort of deck penetration against the Tirpitz. (Dr Raymond Cheung)
Both weapons enjoyed initial successes. The first Hs 293 attack was mounted against escort vessels in the Bay of Biscay, where they were blocking an important U-boat route. On the afternoon of 25 August 1943, twelve Do 217s attacked a group of eight escorts. None of them was equipped for long-range controlled AA fire. Of twelve Hs 293 launched, five went wild and the others made only near-misses. Two days later, however, a similar attack by eighteen Do 217s on five ships sank the sloop Egret and badly damage the destroyer Athabaskan. In this case only half the missiles remained on course.
The Germans then shifted their missile force to the Mediterranean to contest the invasion of Italy. On 29 August the fighter direction ship Ulster Queen and the small destroyer Cleveland were attacked using FX bombs, but neither was badly damaged; on 5 September the cruiser Orion was similarly missed. However, they were much more successful when the Germans used it against the Italian fleet steaming to Malta on 9 September. The battleship Italia was damaged and her sister Roma sunk.
Further attacks were made on the Allied fleet off Salerno between 11 and 17 September, some by FX 1400 and two using Hs 293. FX 1400s successfully hit the battleship Warspite and the cruisers Uganda and USS Savannah. Warspite was badly damaged and was never fully repaired (she managed to bombard Normandy beaches with only three of her four turrets, and with her machinery largely out of service). Savannah suffered a direct hit through a turret roof. She survived because her thin hull blew open in time to flood her magazine before it could explode. These were the last FX 1400 attacks.
On 30 September an Hs 293 attacking ships in harbour at Ajaccio sank an LST; another caused minor damage to a French destroyer. The missile was then used mainly against convoys (four dusk attacks), against a convoy in the Atlantic (by sixteen long range He 177s), and in moonlight in the Adriatic. The Atlantic attack sank a straggler and damaged another ship in the convoy, and the moonlight attacks scored two hits on destroyers but did not sink them. Hs 293s were used again in January 1944 off the Anzio beachhead, sinking the cruiser Spartan and damaging the destroyer Jervis; a US destroyer and a merchant ship were also damaged. It appears to have been used in Normandy.
The Royal Navy enjoyed some success in engaging the bombers which launched and guided Hs 293s using anti-aircraft guns. It promulgated a tactic in which a ship should turn as soon as the run-up to launch began to keep the launch bomber as far forward as ‘A’ arcs permitted. As the gliders approached, a ship should alter course to keep them ahead in the hope of making evasive turns. Presenting bow or stern would reduce the chance of a hit to a quarter of that expected by a ship presenting a beam aspect. Since the bomber relied on a continuous view of the target in order to guide the missile, smoke might successfully shield a convoy. Similarly, in the case of FX, long-range anti-aircraft fire could attempt to destroy the parent aircraft both before and after it dropped the bomb. Any evasive action should be toward the direction of attack, as it was easier for the bomb aimer to increase than to decrease the range of the bomb.
The Germans sometimes combined guided weapon attacks with more conventional ones: ships experienced synchronised attacks by Fw 190 fighter-bombers at low altitude while a Do 217 dropped FX from high level. They also tried a combination of Hs 293 and torpedo bombers against convoys.
Although in theory the best counter to missile attack was to use defending fighters to destroy the carrier aircraft, effort was concentrated on electronic countermeasures: receivers to detect the command signal and jammers to disrupt it. Jamming worked even though the antenna on the missile looked up or back at the guiding aircraft, rather than towards the jamming ship. For the longer term, both the Royal Navy and the US Navy began work on guided anti-aircraft missiles (in the US case, the Kamikaze threat spurred action). Both navies were uncomfortably aware that the Germans were operating at stand-off ranges at the outer limit of gun effectiveness (the maximum
