BOAC,
...could we be confusing delayed flap extension in adverse weather?
This is the METAR at the approximate time of departure, I doubt that it is considered adverse (from meteocentre.com)
EDDF 25/1420 6.2 1002.0 3/1 87% 110 2 -RA FEW007 SCT011 BKN018 TEMPO BKN010=
I am being extra cautious, and verifying information with the professional flying community since I do not want to put the crew in an uncomfortable position to answer questions on safety if it is any mistake in my observations. But, now, unfortunately it seems it's not...
Thx.