For years the municipal airport here has been a haven for people like Herb Morrison, a local lawyer who soars on weekends behind the controls of his own airplane.

"It's been a very nice general aviation airport," said Morrison. "There's always been a lot of courtesy here."

A sense of camaraderie among private pilots has made the airport an ideal place to fly, he said. But city officials are now saying that good will may no longer be enough to keep this bustling airport on an even course as the demand for use here grows.

Suburban growth has restricted operations at neighboring Montgomery County's airpark and crowded conditions at National Airport have made it more difficult for private planes to land there. As a result, air traffic is increasing here in Frederick.

Although there is no control tower at this small airport, the facility has a sophisticated "instruments only" radar system for bad-weather landings. Actor Charlton Heston, former football great Johnny Unitas and other travelers frequently use the airport when they fly to Washington by private plane, officials here said.

The airport, now the home terminal for about 300 aircraft -- from single-engine antiques to corporate jets -- is about to undergo a $5.3 million expansion. One of two existing runways will be lengthened to 5,200 feet and a third will be built.

Operations are currently guided by Federal Aviation Administration regulations designed for airports without control towers that are staffed with FAA flight controllers.

But city officials say the facility is getting too crowded to rely on informal FAA procedures. To remedy that, the city Airport Commission two weeks ago proposed a series of formal regulations covering nearly every aspect of airport operation.

"The airport is going through tremendous development. We just thought it was necessary to have these regulations," said Allan Merchant, a city alderman who chairs the three-member commission.

The rules have been greeted with little enthusiasm by the Frederick Airport Association, a group representing private pilots who keep their aircraft on the field or belong to one of its many flying clubs.

"The general attitude is if it ain't broke, don't fix it," said Morrison. "But we have other concerns as well."

Chief among them is a feeling that the city government is trying to tell pilots how to fly. The regulations, the plane owners say, spell out such rules as mimimum altitudes for take-offs and landings and mandatory flight patterns.

According to pilots, some of the proposed procedures conflict with or are already covered by established FAA regulations. Others, they say, may not be the best procedures to use under all circumstances.

"It says you must turn left if you are departing the airport's traffic pattern, but that's usually left to the discretion of the pilot under federal aviation regulations," said Frenis Hoffman, a spokesman for the airport association.

"The city is acting as though it wants to control the airspace above the airport, and I don't believe they have a right to do that," Hoffman said.

Proposed regulations also closely control when and where commercial operators can provide fuel and other services to pilots on the field.

Pilots say the rules restrict competition and appear to favor Frederick Aviation, Inc., the largest and oldest commercial operator, which leases virtually all of the ground and doubles as airport manager.

In October, a second commerical operator known as International Aviation, opened for business near the field and began selling aircraft fuel from a mobile tanker.