Oh dear!
Right, how about if I ask it this way...
Let's say we're in OP DES at 250Kts (ATC restriction) and achieveing an average rate of descent of about 1,200 to 1,300 FPM. If I extend half speedbrakes (A320 with AP engaged), what would you expect the descent rate to increase to?
Dct_Bombi,
I wish I was! I'm over the sea with a G reg crowd. Are you a recent addition to EILand?