Here's some info on using airplanes (http://mars.jpl.nasa.gov/programmissions/missions/missiontypes/airplanes/ http://mars.jpl.nasa.gov/programmissions/missions

Here's some info on using airplanes (http://mars.jpl.nasa.gov/programmissions/missions/missiontypes/airplanes/ http://mars.jpl.nasa.gov/programmissions/missions/missiontyp...) and balloons (http://mars.jpl.nasa.gov/programmissions/missions/missiontypes/balloons/ http://mars.jpl.nasa.gov/programmissions/missions/missiontyp...) on Mars. In short: it's possible.