TD:
AAR has been stopped and the SCP switched off . Why ? Because they were/are a significant hazard to aircrew. As the loss of XV230 showed.
I would like to amend that statement:
The SCP was definitely a significant hazard to the aircraft and crew in the years leading up to 2004, as demonstrated by the incident on XV227. Thereafter, it was made safe. It still is today.
AAR is safe. Nimrod is no more dangerous to refuel in the air than any other type.
AAR and SCP (or crossfeed pipe) operating simultaneously (or during the same flight): extremely dangerous.
This is the circumstance that should been identified and prohibited under airworthiness requirements. It is irrelevant to serviceability and maintenance activities, which we know were carried out to the normal high standards.
Lets not get into a terminology bunfight over "engineers" (ground or air) and "technicians"
Ed Sett