The popularity of flying privately is rising among those who can afford it, and aviation companies are responding accordingly by expanding.

Surf Air will be increasing its fleet by 40 percent by adding five new Pilatus Pc-12 NG business turboprops. They will also be flying customers privately to four new California destinations.

PlaneSense, another private aviation company, just  purchased five remanufactured Nextant 400XTi business jets for $25.75 million. PlaneSense plans on getting the first of the new jets in the air as early as June.

Flying privately is paid for monthly, with prices varying. SurfAir charges $1,750 per month with a complimentary round-trip guest ticket available once a quarter. Customers can alternatively pay $2,250 per month for a package that includes a guest ticket on every flight.

Private air travel has become a hit on the luxury market. Flyers who can afford it like to take advantage of the quieter private flights, access to private terminals, and the flexibility of being able to fly as much as they want to per month, with the only limitation being the company’s flight schedule.