Low-cost carrier Frontier Airlines has signaled its intention to add 21 new destinations and 85 new routes in the US – a 30 per cent increase in domestic destinations and doubling the size of the airline’s route network.

Once completed in spring 2018, the expansion will see Frontier operating in 82 US cities, with a total of more than 1,000 routes nationally by next summer.

Of the 21 “new” destinations, three — Buffalo; Charleston, S.C.; and Pensacola, Fla. — have never been served by Frontier before, USA Today reports. The remainder are cities previously served by Frontier where service is being restored.

The expansion includes additional non-stop flights in destinations already served by the airline, as well as more winter flights to warm-weather destinations like Tampa, Miami, Orlando, Fort Myers, Fla., and Cancun, Mexico.

The airline will significantly expand service via its Denver hub, adding six new destinations immediately and 15 more in 2018. Other airports seeing multiple additions include Austin, Texas, Buffalo, NY, Cincinnati, Ohio, Fort Myers, Florida, Islip, Miami, New Orleans, Orlando, San Antonio, and Tampa.

Start dates for the new services promised in 2018 have not yet been announced.

Meanwhile there was controversy surrounding the launch for the new services, with Frontier’s head of communications Jim Faulkner sending an “inappropriate” email to Denver’s 9New Kyle Clark, following the reporter’s decision to focus on Frontier employees having to hold up a banner during the launch event.

Faulkner accused Clark of having “some sort of short-man’s disease”, and asked “Did your golden retriever die before you took this picture?”.

Frontier’s vice president of marketing later released the following statement:

“Mr. Faulkner’s inappropriate comments regarding Mr. Clark do not reflect the views of Frontier Airlines. It was a misplaced way of defending comments made about our employees on Mr. Clark’s show last night.”