Canadian canopy
Hate to burst your bubble (excuse the pun) but the Canadian blown canopy was introduced with the DHC-1B-2-S3 model ordered by the RCAF in late 1949.
Built to RCAF Spec.11-24 Issue 1, the blister canopy (which differed from the earlier RCAF Chipmunks with greenhouse style models) was first flown on DHC test and development aircraft CF-FHY through late 1949 and early 1950. First deliveries of the new model Chipmunks were accepted by the RCAF in mid 1950.
Meanwhile British production of Chipmunks with the sectioned canopy started in late 1949, by mid December only 17 had been completed at Hattfield. Initial deliveries to the Oxford and Cambridge UAS's began in the early spring of 1950 while production moved to Chester. With approx 900 yet to be built in the UK over the remaining production run it is clear to see that the Canadian bubble canopy was in use just as UK production was getting underway and that the bulk of UK production occured after the blister was in use in Canada.
I own and fly a Canadian model, visibility is magnificent, no drafts, rattles or leaks but the greenhouse style does (in my mind) visually represent a closer tie to the de Havilland models of the 1930s and has a nice clean top line following that of the fuselage.
Cheers,
H. Shields