XP327
Aldons,
Thanks for your valuable contributions to this Thread. You have the most relevant information about the detail of what happened and its aftermath.
As to why four lookouts didn't fly, the reasons are legion: perhaps the crew didn't want No: 4 'cause of the fuel/payload, maybe he was late arriving, perhaps he decided he couldn't be bothered, if he worked with one of the others perhaps his 'chiefy said; 'both of you ain't going'.
I have never heard anybody mention the fourth man and his 'lucky escape' and one might have thought it would have come out during the enquiry and certainly the search was for five men not six.
The possible place to look is the Sqn Form 541 at the National Archives. This is the schedule of sorties and if a name was entered in the 541 and then crossed out it would mean that up until very close to the take-off there had been an intention to take four lookouts.
Not sure if you want to take this forward or I can ask my NA researcher to look next time she is doing some work for me.
Anyway, thanks again for your contribution, which I for one have found most helpful.
O-D