The de Havilland / AIRCO DH.9 two seater tractor biplane designed and built by The Aircraft Manufacturing Co. Ltd., Hendon, London, N.W.9. – Engine 250 h.p. Siddeley "Puma". Speed at 10,000ft., 110
Siddeley Puma Aero Engine first Run @ Retrotec 20-04-2016 - YouTube
File:Siddeley Puma 250 hp L'Année Aéronautique 1920-1921.jpg - Wikimedia Commons
HAC: DH9 Restoration
Siddeley Puma, 209hp
Siddeley Puma Aero Engine second Run @ Retrotec 20-04-2016 - YouTube
DH.9 Armstrong Siddeley Puma by Small-Brown-Dog on DeviantArt