Owen. There is something amiss here.Postwar RAF servicemen posing at a Luftwaffe scrap grave. I recognised immediately the new type working blue blouse which was not issued during the war....my working blue blouse in 1952 was a wartime issue with manufactured date of. if I remember correctly,1941.I would say that the new type of working blue blouse came in about 1950 but old blouses would be issued until stocks were exhausted.There was no such problem with the best blue tunic as it remained as it was during the war. Further the technical ranks as I will expand on, did not come in until about 1950 which also put a further classification of SAC (three props) above LAC and under Corporal. The technical ranks introduced were as follows,all with inverted stripes. One stripe inverted.................Junior Technician......this is our man and he would be a Fitter in his trade designation. Two stripes inverted................Corporal Technician Three Stripes inverted.............Sergeant Technician Three Stripes inverted with a crown on top (as found as on a Flight Sergeant's uniform)......Chief Technician. When the V bombers entered service,the RAF adopted a maintenance structure where a Chief Technician became the dedicated "Crew Chief" for an individual squadron aircraft.