Dr Alexander was selected as a NASA Flight Surgeon in November 2004. His NASA Flight Surgeon Training included orientation briefings and tours, numerous scientific and technical briefings, intensive instruction in Shuttle and International Space Station systems, physiological training and ground school to prepare for T-38 flight training. He is a certified Flight Controller for the International Space Station and Shuttle. He served as Deputy Crew Surgeon for Shuttle Mission STS-123 and ISS Expeditions 11, 23, and 47. He was the Lead Crew Surgeon for Expeditions 14, 33/34, 42/43 and 52. He was also Lead Crew Surgeon for STS-128.
His titles include:
- Lead, Medical Operations, Suit Design Team – Constellation
- Lead, Medical Operations, Suit Design Team – Commercial
- Medical Operations Lead – Direct Return Operations – Soyuz Crew Recovery
- oVIIP (operational Visual Impairment and Intracranial Hypertension) working group member
- Intraocular Pressure Training Lead and In-Flight Director
- SME Subject Matter Expert) Atmospheres and CO2
- Directs the Operational CO2 working group
- Research includes terrestrial chamber and on orbit effects of various concentrations of CO2 and O2
- Design Requirements reviewer for atmospheres the vehicles: Constellation, Orion, SpaceX, Boeing
- Medical Spaceflight Atmospheric Standards Lead
His military Experience Includes:
- Squadron Medical Element 39th Fighter Squadron, Mountain Home ID
- Lead on Emergency Response Package for Expeditionary MEDical Support System
- Flight Surgeon, then Chief of Flight Medicine, and then Chief or Aerospace Medicine at the 149th Fighter Wing
- Currently:
- Officer in Charge and Flight Surgeon on the Regional Medical Planning Team – Region 6 (Texas, Oklahoma, Louisiana, Arkansas, New Mexico)
- Deputy State Air Surgeon, Texas