Buster and those interested.
I think that the mere idea of cutting up Window to measure in a weaving aircraft at night with the flak and searchlights all around ! ... No way and possibly the following detailed description that I found from my Squadron's (51) Official Biographer's excellent book "Snaith Days" will bring out a very good description of "Window" and how it was used.
During the third week of July 1943 a large consignment of brown paper parcels size 12 x 2.5 x 2.5 inches was under very secure storage at Snaith
These parcels each contained 2,000 Window strips size 30cm x 1.5cm made of very thin aluminium foil bonded to black paper. Later production of Window was 27cm long with a brown paper backing. Foil was already available for the production of paper capacitators used in radios etc. The length of these strips was such that they acted as half wave dipoles resonating and re-radiating a signal at the frequency of 450 to 500 MHz as employed by "Wurzburg" ground and "Lichenstein" airborne radar. One bundle when dropped from a Squadron aircraft would produce the same radar response as a Halifax Bomber.
At around teatime on the 23rd July 1943 the aircrew went in for briefing for the raid on Hamburg. At this session the briefing was given by the Squadron Commander W/Cdr. Franks and gave information that had never been given before at a Command briefing. He explained that this new RDF countermeasure ,"Window" had such a devastating effect on the enemy's ground defences that the RAF had witheld from using it until they , the RAF , had devised a defence for it. ( We were never told what that "Defence" was !).
At their briefing, the Navigators were given two points on their track at which Window dropping had to start and stop. This night the points were Long. 8 degrees East on the route in and Long 8.5 degrees East on the way back. ( A chart of the route in the book gave the Northerly routes in and out and were roughly over the North Sea stretch that led into the Delta of the River Elbe leading up to Hamburg and avoiding the defences of the Friesian Islands.) The W/Ops had the unpopular task of timing and dropping the bundles down the flare chutes at the rate of one bundle per minute. Each aircraft dropped 100,000 strips, falling at the rate of about 300 ft.per minute. It was not a popular task because the strips were often blown back into the aircraft and also there was the chance of the stub aerial of the IFF being damaged by the bundle before it had opened.
When the bundles were delivered to the aircraft by the groundcrew they were given the story that they were a new type of "Nickel", the code name for the propaganda leaflets dropped when the bomb doors were opened over the target.
The convergence point for the different Groups of Aircraft taking part in the raid marked the spot where the dropping of Window commenced and the complete bomber stream for this raid was about 200 miles long.
The effect of the strips became apparent straight away as the searchlights seemed to be aimlessly probing the sky looking for targets, different from the normal situation when Wurzburg controlled searchlights could help the uncontrolled searchlights find the target (The "dreaded" blue beam ! Reg). The now uncontrolled Flak batteries became very inaccurate in their shooting. In order to assess the effect of Window on this initial raid the Wops were told not to carry out "Tinsel" jamming operations so that the "Y" listening service in the UK could monitor the reactions of the German GCI controllers. Window did not affect "Freya" E W Radar but it jammed Wurzburg which was used with the "Lichenstein " in the Fighters to guide them on to the trapped Bombers. Their reports indicated that a state of complete panic had reigned with Pilots calling the Controllers Imbeciles when they were directed on to hundreds of Bombers and found none. There were even cases of Aircraft crews ordered to report to their Commanders immediately upon landing ; The word "Cowardice" was reputed to be heard floating around
the air waves and one weary Controller when switching off his set was heard to say the German equivalent for "What a F****** night this has been.!
The report goes on to explain that the use of "Window" was to produce a considerable reduction in casualties from about 6% average for the Command before the use of Window to about 2.5% for the Hamburg raids. The Germans attempted to limit the effects of Window by getting the GCI controllers to give running commentaries to night fighters and to start using "Thame Sau" ( Tame Sow dayfighters) to take part in freelance operations alongside the existing "Wilde Sau" aircraft. These tactics caused the Luftwaffe to alter their defence tactics with increased flexibility and , very quickly, it was considered that these changes would be to the detriment of the RAF. However it was used very successfully on the important destruction of the Peenemunde raid , on which I took part and the SQdn's route out was Flamborough Head;55.20N 80.29E;54.24N13.40E; Island of Rugen; Peenemunde; Mando; Snaith. Bomber Command had carried out a very successful diversionary operation by sending eight Mosquitos to Berlin with "Window", capitalising on it's successful raid on Hamburg. This "Spoof" raid attracted the attention of over 200 nightfighters ,conseqently only a few arrived at Peenemunde to catch the last wave of bombers. Nevertheless 29 aircraft were shot down in the bright moonlit sky of the last wave out of a total of 40 aircraft lost. As 51 Sqdn. was in the first wave it suffered no losses and I see that I put in my Log Book the words.."Very Quiet trip". The raid was considered a succcess and the "V" weapon programme was put back for about two months.
I hope that some of the Questions that you asked were answered and the use of "Window" understood more readily. Reg