The Vigilant T1 is the RAF's version of the very popular Grob G109B motorglider. It is used to provide Air Cadets with training in basic flying techniques, enabling them to reach a standard whereby they can go solo. Another operator is the Central Gliding School at Syerston, where Vigilants train instructors for the RAF's Volunteer Gliding Schools, 17 of which operate the type. Apart from the lightweight, composite airframe, Grob also makes the four-cylinder, air-cooled, 95hp piston engine. The Vigilant entered service in 1991, replacing the Slingsby Venture. While it launches itself, the type may still be flown like a glider, being able to soar in thermals if conditions are right.