Fuel Paths
EdSet, when fuel 'blows off' during AAR, the quantity of fuel can be considerable - depends upon how quickly aircrew notice and stop receiving. This fuel can track all over the aircraft and get into panels and compartments. Since 30, 'blow offs' have been reported and this event is better understood; hence, the revised AAR procedures post 30. Before 30, there were no incident reports to highlight that 'blow off' was happening.
NB: Routine AAR was suspended after 30. Authority given for operationally essential AAR under Service Deviation. Since 35, operational AAR also suspended - until they figure out why, what looks like a perfectly serviceable coupling, leaked during airborne AAR but does not leak during AAR behind a Tristar on the ground.