The Associated Press recieved exclusive access to the flight logs at Port-au-Prince airport, revealing a chaotic period where distribution of vital aid was often delayed or rerouted. AP reports:
The Air Force did initially give priority to military units that were sent to secure the airport, distribute aid and keep the peace. But then it started taking flights according to a reservation system open to anyone.

Because of that, key aid was delayed in some cases while less-critical flights got in.
One particularly striking example is when Planes deliverying hald a field hospital were allowed to land, but the planes that carried the other hald were diverted to the Domincan Republic "delaying the opening of one of Haiti's first post-quake field hospitals."

The US Air Force began directing traffic the day after the earthquake and took total control a few days later. Aid groups, including Doctors Without Borders complained that their planes were delayed or redirected in favor of US military aircraft. French and Italian officials echoed the complaints, as did Haitian Prime Minister Jean-Max Bellerive.

Lt. Gen. Spears of the US Air Force defended the early prioritization of military flights:
"No one knew what the response of the Haitian people would be to this terrible event, but we knew we had to secure the airport to save lives," Spears said. "So yes, we did send in men and women with guns, and we have not needed to use them."
The logs show that on the first day the Air Force had total control, of 73 planes that landed at least 24 were from either the military or US government.

The end result, according to the AP:
Church of Scientology ministers landed, as did AP reporters, CNN's Anderson Cooper and diapers from Canada. But a French portable hospital and planeloads of doctors with medical supplies were diverted to the Dominican Republic.