While the recent large-scale startup scene has been concentrated in Canada and Europe, the emerging development in the U.S. has been the stand-alone small-jet airline. You've seen plenty of small-jet airlines operating as feeders to the big airlines at their major hubs, but independent small-jet carriers have had a spotty history. Over the last few years, however, several have emerged as possibly here to stay. I looked at three of the bigger efforts.

OneJet

This airline operates most flights to/from a primary hub at Pittsburgh and a secondary hub at Milwaukee, plus some point-to-point links, connecting to Albany, Buffalo, Cincinnati, Columbus, Hartford, Indianapolis, Kansas City, Louisville, Omaha, Providence, Richmond, and West Palm Beach. This list is not permanent, however: the line is quick to add new routes and drop those that underperform. It flies a mix of small jets, from nine-passenger Cessna Citation to 50-passenger Embraer 145. It generally serves major air carrier airports, using main terminals, and flights are tabulated by the ITA Matrix system used by such metasearch engines as Google Flights ad TripAdvisor.

Fares appear to be competitive with fares on larger lines. For a sample mid-August trip from Kansas City to Pittsburgh, OneJet quoted round-trip fares on nonstop flights at $238-$258, compared with $332 one-stop on United. OneJet quoted Hartford-Indianapolis at $238 with a Pittsburgh connection, compared with $350 on Delta via Atlanta or Detroit. These, of course, are limited advance-purchase fares; last-minute fares are much higher.

OneJet stresses upgraded cabin service, including a checked bag. Some flights include WiFi and drink service. Although cabins are small, most seats are either 1-1 or 1-2, with no middles. 

OneJet recently acquired Ultimate Jet Charters, a smaller line that operates a scheduled "Air Shuttle" flying from a base at Cincinnati's in-town Lunken Field. Ultimate Air Shuttle operates in a much different way than OneJet. All flights are on 30-passenger Embraer jets. Some flights operate to general aviation airports rather than major airports: DeKalb-Peachtree for Atlanta, Cleveland Lakefront, and Morristown for New York; even at major fields Chicago/Midway and Charlotte, the line operates from fixed-base operators rather than main terminals. The plus is much less hassle for security and boarding, but generally much poorer ground transport options.  

Air Shuttle fares are much higher than OneJet's: A sample, a round-trip from Cincinnati to Morristown in August listed at $749, compared with $100-$150 to other New York airports on Allegiant or Frontier. As of now, ITA matrix does not show Air Shuttle flights.

So far, OneJet has given no indication whether it will attempt to rationalize the two systems or instead continue to operate them independently. It will be interesting to watch.

VIA Air

VIA Air operates more than a dozen point-to-point routes, mostly out-and-back from either Austin or Orlando/Sanford. Austin flights go to Baton Rouge, Branson, Little Rock, Oklahoma City, Steamboat Springs, Tucson, and Tulsa; Orlando flights go to Baton Rouge, Beckley, Charlotte, Jackson, Mobile, Montgomery, and Parkersburg; a non-base route operates between Charlotte and St Augustine. VIA uses main terminals. Flights are on 50-seat Embraer 145 and 30-seat Embraer 120.

Fares are competitive on most routes, such as Austin-Tucson, at $378 round-trip nonstop compared with $384 one-stop on American. Fares are higher absent competition, such as $398 for the relatively short Austin-Branson round-trip. The ITA Matrix search system carries VIA Air flights and fares.

Silver Airways

Silver doesn't quite belong in this list; it flies 34-passenger turboprop Saab 340 rather than jets, but otherwise it fits the mold. It operates a complex network mainly linking nine Florida cities plus Huntsville with seven destinations in the Bahamas. Most flights originate or terminate at Fort Lauderdale or Orlando; Bahamas service is concentrated on Marsh Harbour. Silver also operates two route systems outside its primary network: Boston to Bar Harbor and Branson to Chicago, Houston, and New Orleans. Many routes are seasonal. Some routes are code-shared with large lines. Flights use main terminals at the major airports. Silver has recently acquired Seaborne Airlines, based at San Juan Puerto and serving key Caribbean destinations as far south as Dominica.

Fares are generally competitive: Ft Lauderdale-Nassau is $300 round-trip, compared with $275-$289 on Bahamasair. The ITA Matrix search system carries Silver flights and fares.

Above image by Carlos Yudica via Shutterstock