The Jero/Farman (Henri) H.F. 20 was developed from the H.F.16 of which it inherited the same "fuselage" but was equipped with a higher undercarriage, larger capacity fuel tank (which allowing flights to up to three hours) and a redesigned elliptical rudder. Powered by a Gnome 80hp rotary engine, the H.F.20 could reach a maximum speed of 105 km/h. Jero (Bollekens) delivered six H.F.20's to the military at Brasschaat via Sint-Job-in-'t-Goor in July 1913, followed by two more the following months. These aircraft participated in the manoeuvres in the "Entre Sambre et Meuse" region at the end of August and early September of that same year. A non determined number of supplementary H.F.20 was delivered later on.