He might be going out to do med stores as previously mentioned (since the medics seem to think they have such special stuff to handle). TMW do perpetuate the myth they are special after all.
samuraimatt - there were 4 Musicians 'discovered' in theatre not doing a great deal - they were re-tasked to cover the pax handling role for the helicopters (escort across pan etc) and freed up Movers for more technical aspects of their trade, thus helping a drastically undermanned Trade.