An affinity charter is slightly different in that, although all of the passengers are affiliated with a specific business, group or organization, each pays his own air fare. The passengers might sports or music fans traveling to a special event, or a bunch of friends going on vacation. With this type of charter, none of the seats can be sold to members of public.
The key words here are prop planes, turboplanes, and light jets. Prop planes like the Cessna Caravan are popular because they're roomy (the seats are like business class, and often configured face to face). More popular these days are planes like the six- to eight-seater Pilatus PC-12, and KingAirs, which fly faster and feel more like jets. And then you get into light jets like Learjets, Embraer Phenom 300s, and Citation CJ3s, and Hawkers, all of which are sleeker and more streamlined, and can fly for four to five hours, for slightly longer trips.
Charter, also called air taxi or ad-hoc flights require certification from the associated country's regulating body such as the FAA in the U.S. The regulations are differentiated from typical commercial/passenger service by offering a non-scheduled service. In the U.S. these flights are regulated under FAA Part 135. There are some cases where a charter operator can sell scheduled flights, but only in limited quantities.
The very light jet (VLJ) is a classification initiated by the release of the Eclipse 500, on 31 December 2006, which was originally available at around US$1.5 million, cheaper than existing business jets and comparable with turboprop airplanes. It accompanied a bubble for air taxi services, exemplified by DayJet which ceased operations on September 2008, Eclipse Aviation failed to sustain its business model and filed for bankruptcy in February 2009.
In October 2017 Jetcraft forecasts 8,349 unit deliveries in the next decade for $252 billion, a 30.2 $M average. Cessna should lead the numbers with 27.3% of the deliveries ahead of Bombardier with 20.9% while Gulfstream would almost lead the revenue market share with 27.8% trailing Bombardier with 29.2%. For 2016-2025, Jetcraft forecasted Pratt & Whitney Canada should be the first engine supplier with 30% of the $24B revenue, in front of the current leader Rolls-Royce at 25%. Honeywell will hold 45% of the avionics $16B revenue ahead of Rockwell Collins with 37% and Garmin.