David served in the Australian Defence Force for over 22 years. An Army pilot, he flew helicopters and fixed wing aircraft and was the Senior Flying Instructor at the School of Army Aviation in Queensland.

Graduating as an experimental test pilot from the Empire Test Pilots’ School (UK), he finished his full time career in Defence as the Commanding Officer of the RAAF Aircraft Research and Development Unit.

Elected to the House of Representatives as the Member for Wakefield (SA) in 2004, he served in the Parliament until 2007. David continued to fly as a test pilot and ran a small business working in the Defence and Aviation sectors prior to being elected to the Senate in 2010, 2016 and again in 2019.

In the (45th) Parliament, David was sworn as the Assistant Minister for Defence.