The Tweed-New Haven Airport Authority on Wednesday approved a 20-year master plan that includes a proposed 600-foot-long runway extension.

The 20-year-plan was developed by consultants Edwards & Kelcey of Manchester in an effort to attract more business to the region by allowing larger planes to land at the airport.

The Federal Aviation Administration and the state Department of Environmental Protection also must approve the plan, a process that could take up to nine years, an authority member told television station WTNH.

The plan calls for extending the main runway from 5,600 feet to 6,200 feet, expanding the terminal, improving access roads, and cutting trees and brush that shorten the runway’s usable length.

The authority also would pave two 1,000-foot runway safety areas scheduled to be built on both ends of the runway. That would allow jets to use an additional 1,000 feet for takeoffs, creating what effectively is a 7,200-foot runway. The runway would be 6,200 feet for landings.

According to the proposal, the improvements would let regional jets profitably fly from Tweed to airports within 800 nautical miles. That distance would open up the possibility for service to markets such as Chicago, Atlanta, Detroit, Cleveland, Cincinnati and Charlotte, N.C.

Currently, in order to carry enough fuel to make it to a place such as Chicago, jets must carry less than full loads of passengers.

While the expansion plan is the most ambitious of the recent options, it is milder than two options the authority dropped last June. They would have extended the runway by 1,000 feet and 2,000 feet, respectively.

The improvements would affect 22 acres of wetlands and cost an estimated $60 million, with most of that money to be reimbursed by the federal government.

Critics said they had noise and traffic concerns, while advocates said a larger runway would help the regional economy.

“A lot of businesses in southern Connecticut, in particular, felt almost cut off from easy air access and to some extent cut off from the global economy,” said Kevin Kane, a member of Let’s Improve the Future of Tweed, or LIFT.

–Associated Press