The AN-124 has recently became a frequent visitor at my home base - actually it comes there every day. What I have noticed is that every time after lining up the runway, the crew says they need about 3-5 minutes before they can commence the takeoff. It usually causes quite a lot of mess in the airspace of what is a relatively calm airport. I can't imagine what would happen in say LHR, or FRA
So - why do they have to stay so long on the runway?