JF wrote:
Take a Harrier on a heading of north doing 60 kt IAS on a flat calm day. Now change you heading to south in three to four seconds (easily done with full rudder I can assure you). I think you will probably be able to see for yourself that you will end up not with less than about 45 kt of backwards velocity (a bit more than a ‘reduction’ in IAS) because the drag that acts for that brief period of sideways flight is fighting the momentum of eight tons of aircraft doing 60 kt and does not represent much of a 'brake'.
BOAC knows ‘cos he was a Harrier pilot too.
Not that I was Harrier pilot (although I was a design engineer at Hawker's during your era, JF!), but do you not think your momentum example applies equally in turning upwind? Just posing the question!
Regards
Islander2