[2] German engineer Max Kramer, who worked at the Deutsche Versuchsanstalt für Luftfahrt (DVL), had been experimenting since 1938 with remote-controlled free-falling 250 kg (550 lb) bombs and in 1939 fitted radio-controlled spoilers.

The disadvantage with this — in comparison to fully autonomous-guidance glide bombs like the operational U.S. Navy's Bat radar-homing glide bomb, used against Japan in 1944–45 — were that the aircraft had to be flown towards the target on a steady course and that as the missile neared its target it became possible to misguide it by jamming its radio channel.

It was found that the launch aircraft had to "toss" the bomb slightly, climbing and then descending, to keep it in view ahead.

Several attacks around Sicily and Messina followed, but no confirmed hits were made and it appears the Allies were unaware that the large bombs being dropped were radio-guided weapons.

[8] The American light cruiser USS Savannah was hit by Fritz Xs at 10:00 AM on 11 September 1943 during the invasion of Salerno, and was forced to retire to the United States for eight months of repairs.

The blast tore a large hole in the ship's bottom, opened a seam in her side, and blew out all fires in her boiler rooms.

Savannah lay dead in the water with her forecastle nearly awash, and eight hours elapsed before her boilers were relit, allowing the ship to get under way for Malta.

SS Bushrod Washington was hit by a glide bomb, either a Fritz X or a Hs 293, on 14 September while offloading a cargo of fuel.

[Note 2] SS James W. Marshall was set on fire by a conventional bomb, Hs 293 or Fritz X on 15 September.

A witness aboard a ship nearby, Joseph A. Yannacci, attributes the attack to Ju 87 "Stuka" dive bombers, which were too small to carry glide bombs.

KG 100 achieved another success with Fritz X while the British battleship HMS Warspite was providing gunfire support at Salerno on 16 September.

She took on a total of 5,000 tonnes of water and lost steam and consequently all power, both to the ship herself and to all her systems, but although the damage had been considerable, Warspite's casualties amounted to only nine killed and fourteen wounded.

The control system used by the Fritz X relied on radio contact between the bomb and the guidance unit, and was susceptible to electronic countermeasures.

The system met with some success, but proved cumbersome and easily overwhelmed if large numbers of weapons were deployed simultaneously.

In early 1944, as the US Army was engaged in the Battle of 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 on a Fritz X, by jamming the Straßburg receiver's intermediate frequency (IF) section.

By the time of the Normandy landings, a combination of Allied air supremacy (keeping the Luftwaffe's bombers at bay) and ship-mounted jammers meant that the Fritz X had no significant effect on the invasion fleet.

This is unlikely, as III./KG 100, the unit which had carried the Fritz X into combat, had largely been re-equipped with the Hs 293 by that time for its anti-ship missions, and the attack on Svenner occurred before the first glide bombers launched their assaults on the Normandy beaches.

The Fritz X has been credited as responsible for the loss of the hospital ship HMHS Newfoundland at Salerno as well as the destroyer HMS Janus and the light cruiser HMS Spartan at Anzio, but these ships were hit by Hs 293s,[10] as demonstrated by the nature of the damage inflicted,[12] as well as by reports from witnesses[13] (in the case of Janus, either an Hs 293 or a conventional torpedo was responsible).