[1][2][3] She expressed an interest in aviation from an early age,[2] and she began taking flying lessons while attending Bennington College in Vermont.
[3] By the time she graduated (early, with a degree in marine biology),[3] she had enough flight hours to be a candidate to join the Women Airforce Service Pilots.
[1] After World War II ended, Haas Pfister purchased (for $750)[2] a decommissioned Bell P-39 Airacobra fighter plane.
[3] Haas Pfister advocated for upgrades to the Aspen–Pitkin County Airport that allowed it to accommodate major commercial traffic.
[4] She founded the Aspen chapter of the Ninety-Nines International Organization of Women Pilots[3] and the Snowmass, Colorado, Balloon Festival.