Small Aircraft
Flight Crew Multiengine; Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 130; Flight Crew Total 2475; Flight Crew Type 300
Distraction
Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Landed As Precaution
Human Factors
I was flying my 12th airdrop relief mission post Hurricane Florence. Conditions on the ground were hectic and we were late in getting loaded. During my preflight; a [non aviation person] started asking questions.  Non-pilot people should not be allowed unsupervised access to the ramp. After the interruption; I finished my preflight. I was preparing to remove my pitot cover when interrupted. I apparently skipped that step. After normal taxi and rotation which showed an indication of airspeed; my airspeed froze at about 20 to 25 knots below normal. I looked out of the window and saw the pitot cover about half on and folded over by the wind (soft cloth cover). I climbed out; requested return to the field; was given priority; and landed without incident. I informed Tower of my omission; apologized for tying up airspace; and was re-assigned a departure slot. No flights were waved off to permit the landing. Despite the distractions; the mistake was completely my responsibility.
General aviation pilot reported an inoperative airspeed indication after takeoff due to the failure to remove the pitot tube cover during pre-flight.