I have revisited the issue of 74 Sqn's losses on 6 May 41.
There were four losses in total, three over France and one as a result of a force-landing in the UK.
The four pilots were Arnott (POW), Boulding (force-landing), Howard (killed), Wilson (rescued from the sea).
The four serials were P7428, P7537, P7928, P8364.
Other quoted serials which can be ruled out are:
P7289 (was on contractor repair at the time)
P8346 (was a 303 Sqn aircraft)
Sadly the ORB appears to be full of errors with regard to serials...
Looking at the AM78s for these four aircraft:
P7428 FBO 6.5.41, SOC 17.5.41
P7537 FBO 7.5.41 (sic), AST 19.5.41, SOC 28.5.41
P7928 FBO 6.5.41, SOC 14.5.41
P8364 FBO 6.5.41, SOC 14.5.41
The one that immediately stands out is P7537. Given that it was allocated for repair before being struck off, this must have been Boulding's aircraft.
Of the other three, two have Casualty Files associated:
P7928 Howard:
https://discovery.nationalarchives.g...ls/r/C16755575
P8364 Arnott:
https://discovery.nationalarchives.g...ls/r/C16755574
This would leave:
P7428 Wilson (rescued from the sea)
The one problem would seem to be the photos of Spitfire ZP-N. How do we know it was Arnott's aircraft?
Andy