HMS Howe

Colombamike

Post subject: Re: HMS Howe

Posted: December 30th, 2012, 8:12 pm

Posts: 1359
Joined: July 27th, 2010, 6:18 am
Location: France, Marseille

KimWerner wrote:

But only because there is a box with some sort of antenna aft near the flagpole (the red arrow) which I can't figure out what is. Anyone who can enlight me?

Hood wrote:

I thought it could be the Type 650 Missile Jammer

klagldsf wrote:

My guess for the object on the fantail is some sort of radar director for the large number of small-caliber anti-aircraft guns there.

This box very likely contain one of the early "anti missile" or "Missile Jammer" system onboard a warship
Especially designed during 1942-1943 to counter early german guided-bomb/missiles (Fritz-X; Hs-293...)

Wiki extract:
"The Allies also went to considerable effort to develop devices which jammed the low-VHF band (48.2 MHz to 49.9 MHz) radio link between the Kehl transmitter aboard the launching aircraft and the Strassburg receiver embedded in the missile. Early jamming efforts by the United States Naval Research Laboratory (NRL) produced the XCJ jamming transmitter installed aboard the destroyer escorts USS Herbert C. Jones and Frederick C. Davis in late September 1943. The XCJ was ineffective because the frequencies selected for jamming were incorrect. This was updated in time for Operation Shingle at Anzio (Italy) with the XCJ-1 system, installed aboard the two destroyer escorts mentioned above as well as the destroyers USS Woolsey, Madison, Hilary P. Jones and Lansdale. These six ships rotated service at Anzio, with three deployed at any time. This system met with some success, though because of its manual interface, it was cumbersome to use and easily overwhelmed if large numbers of missiles were engaged. 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 at Salerno, Italy.

Meanwhile, as attacks were taking place at Anzio, the United Kingdom began to deploy its Type 650 transmitter which employed a different approach. This system jammed the Strassburg receiver's intermediate frequency of 3 MHz, and appears to have been quite successful, especially as the operator did not have to attempt to find which of the 18 Kehl/Strassburg command frequencies were in use and then manually tune the jamming transmitter to one of those frequences. This system automatically defeated the receiver regardless of which radio frequency had been selected for an individual Luftwaffe 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, all in time for the Invasion of Normandy (starting with Operation Neptune, D-Day) and Operation Dragoon in Southern France. This included an updated XCJ-2 system from the Naval Research Laboratory (produced as the TX), the modified airborne AN/ARQ-8 Dinamate system from Harvard's Radio Research Laboratory, NRL's improved XCJ-3 model (produced as the CXGE), the British Type 651 and the Canadian Naval Jammer. Perhaps most impressive of all was 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. Even more sophisticated jammers from NRL, designated XCK (to be produced as TY and designated TEA when combined with the upgraded XCJ-4) and XCL, were under development but were never deployed as the threat had evaporated before they could be put into service. 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 launched at a target (and responding to operator guidance) would achieve a hit or damage-causing near miss."
Source here

and
"Following several intelligence coups, including a capture of an intact Hs 293 at Anzio and recovery of important Kehl transmitter components from a crashed Heinkel He 177 on Corsica, the Allies were able to develop far more effective countermeasures in time for the invasions at Normandy and Southern France. This included an updated XCJ-2 system from the U.S. Naval Research Laboratory (produced as the TX), the modified airborne AN/ARQ-8 Dinamate system from Harvard's Radio Research Laboratory, NRL's improved XCJ-3 model (produced as the CXGE), the Types MAS system produced by the Airborne Instruments Laboratory (at the time affiliated with the Radio Research laboratory), the British Type 651 and the Canadian Naval Jammer. Even more sophisticated jammers from NRL, designated XCK (to be produced as TY and designated TEA when combined with the upgraded XCJ-4) and XCL, were under development but were never deployed as the threat had evaporated before they could be put into service."
Source here

Top

Shipbucket

Who is online