In response to an invitation by the US Army to tender for a light and in particular an economical scout helicopter, in 1960 the Bell Aerospace Corporation developed the model OH-4/206A and later built this as the modified Bell 206B JetRanger for civil customers. By 1997 over 7.700 of the JetRanger with all its later versions had been sold including 4,400 for civil applications, making it the most built helicopter in the world. Crew: one pilot and four passengers; cruising speed: 214km/h; range: 732km.