The Collaborative International Dictionary of English v.0.48:

Planless \Plan"less\, a.
   Having no plan.
   [1913 Webster]

WordNet (r) 3.0 (2006):

planless
    adj 1: aimlessly drifting [syn: adrift(p), afloat(p),
           aimless, directionless, planless, rudderless,
           undirected]