By Jamie Freed (Reuters) -As the clock runs down to Monday’s sanctions deadline for Russian airlines to hand back more than 400 leased planes worth almost $10 billion, foreign lessors are fast losing hope that they will get their aircraft back. Most of the planes are still flying Russian domestic routes, IBA consultancy says, although Bermuda and Ireland – where most are registered – have suspended airworthiness certificates which usually means they should be grounded. Aviation was an early business casualty of Moscow’s invasion of Ukraine, as the West and Russia imposed tit-for-tat airspace b…