Kleynhans has more than 34 years’ experience at Denel in engineering and management, including extensive industrial experience within the state-owned enterprises. He has a Bachelor of Engineering (Electronic) from Stellenbosch University and a Master of Business Leadership from the University of South Africa (2003)

In the 1990s, Kleynhans was the mission systems development manager on the Rooivalk combat support helicopter and the Cheetah front-line fighter aircraft.

After a year at the Department of Public Enterprises and two years at Denel Corporate with the 2005 turnaround strategy of Denel, Kleynhans joined the then Denel SAAB Aerostructures business as Chief Operating Officer.

He worked on the Airbus A400M industrialisation and manufacturing programme and was Chief Executive Officer at Denel Aerostructures before joining Denel Corporate as the Group Executive: Strategy in 2016.