A public charter is one in which a tour operator rents the aircraft and advertises and sells seats to members of the public, either directly or through a travel agent. In the case of public charters, the flight must be filed with the U.S. Department of Transportation, and the tour operator must supply a charter prospectus. The tour operator also must assume a legal responsibility to provide the transportation service, and must abide by DOT requirements for the protection of the clients' money. Public charters often operate only seasonally, and are often sold as part of a vacation package deal, although spare seats may be offered at bargain prices.
In 1999, Bombardier introduced a new type, the Challenger 300, as part of the growing "super-midsize" private jet class. The Challenger 300 – and later Challenger 350, introduced in 2013 – competes with aircraft including the Cessna Citation X and Gulfstream G280. The Challenger 350 carries passengers 3,200 nautical miles non-stop at a cruise speed of Mach 0.80, and features the widest, purpose-built super midsize aircraft cabin with both a flat floor, and in-flight baggage access.
Though the early Lockheed Jetstar had four, most production business jets have two jet engines, mostly rear-mounted podded engine. If mounted below their low wing, it wouldn't allow sufficient engine clearance without a too long landing gear. The HondaJet is the exception with its over the wing engine pods. Dassault Falcon still builds three-engine models derived from the Falcon 50, and the very light jet market has seen several single-engine design concepts and the introduction of the Cirrus Vision SF50 in 2016.