For sale by owner: a vintage airfield located in the heart of New Hampshire's Seacoast. Developers need not apply.

Mike and Cheryl Hart have owned and operated the Hampton Airfield for 30 years. They recently put the property on the market with deed restrictions for $2.5 million.

"We're looking for someone to preserve the atmosphere of a classic antique airfield," Mike Hart said.

The 2,000-foot grass runway and outbuildings are tucked down a short road off Route 1 at the southern end of North Hampton. More than 80 aircraft, half of them classic antiques, are based at the field, which was established in 1946.

Hampton Airfield is known to the public as home of seasonal "thrill rides" in an open-cockpit 1930 biplane. Banner-towing planes take off from the field in good weather to cruise the local beaches.

The Airfield Cafe, leased to and run by the Aversano family, overlooks the field and serves breakfast and lunch each day, all year round.

Full fuel services are available. Ten businesses are leased on the field.

Each spring, a new group of students begins flight lessons at the small flight school. Most earn their pilot's license by fall.

Hart recently gained approval from the North Hampton Planning Board to add six new hangars to be built and sold as condo units, despite protests from some residents concerned it would increase air traffic.

According to Hart, Hampton Airfield is the second or third busiest general aviation airport in New Hampshire, with more noncommercial activity than Pease.

"Grass has a certain attraction," Hart said. "Taildraggers are easier to learn to fly off grass."

The flight school is unusual in starting all students in taildraggers -- aircraft with a third wheel under the tail rather than the nose. The airfield has had continuous Piper Cub training since 1946.

The $2.5 million price includes the existing 40 nested tee hangars, 17 open shed hangars and two maintenance hangars, all fully rented, as well as a converted hangar that serves as the restaurant on one side and airfield operations on the other.

The airfield has 21 tie-down spots, 12 of which are leased.

Hart retired as a Delta Airlines captain one year ago. After the most recent round of cuts in employee retirement benefits, the Harts decided to sell.

"I lost 75 percent of my retirement," said Hart, 60. "It was too big a hit. It's time to cash out."

Hart said he plans to stay involved with Hampton Airfield as one of a group of volunteers who mows, plows and picks rocks off the runway each spring.

The Harts' residential property backs up to the airfield. Over the years, they have purchased and sold abutting property with the aim of creating an aviation-friendly buffer, with 12 house lots with taxi rights to the field.

"The most important aspect(s) of this business are the great customers and pilots that call Hampton home," he said.

"Mike and Cheryl have built rapport," said airport manager George Forrest. "You see a lot of guys and a lot of gals hanging around here. Mike exudes enthusiasm for aviation."

The state of New Hampshire currently has 24 airports open to the public, nine of which are privately owned.

A recent report by the N.H. Department of Transportation, Division of Aeronautics, lists Hampton Airfield as one of two "first-tier" privately owned airports "essential to the airport system." The other is located in Jaffrey.

According to the report: "Hampton Airfield has done an excellent job of establishing covenants and mechanisms to protect the airport from future development. Being located in the desirable North Hampton area, there is strong potential for the property to spark the interest of developers."

Hart said his challenges have included increased property taxes, increased security regulations since 9/11, and escalating insurance rates.

Owning an airfield is generally not a money-making proposition, Hart cautioned. It's about stewardship, he said.

"It's worth preserving," he said. "From day one, that was our purpose -- to preserve an old airfield."