CITY HALL — A national aviation organization has joined the legal battle over the jet ban at Santa Monica Airport, arguing that a city ordinance that restricts such aircraft sets a dangerous precedent.

The Aircraft Owners and Pilots Association (AOPA), which has more than 415,000 members or two-thirds of all pilots in the country, was permitted last week to comment on City Hall’s appeal of the FAA’s decision this summer that City Hall has no authority to ban jets at SMO and the law unjustly discriminates against certain classes of aircraft.

A representative with the AOPA was unavailable for comment. The National Business Aviation Association has also petitioned to participate in the case as a friend of the court, which would allow it to submit a brief.

The case is currently before the United States Court of Appeals District of Columbia Circuit. City Hall filed the appeal on Sept. 4 less than two months after the FAA’s final decision on the issue. The briefing is tentatively scheduled to go from January and March with a decision expected late 2010.

Ivan Campbell, the deputy city attorney, said City Hall did not oppose the AOPA’s petition, nor does it plan to for the National Business Aviation Association, which is also expected to comment in opposition to the ban.

“What we are trying to do is negotiate that they both share and that they not file separate briefs,” Campbell said.

The legal dispute stems from a 2008 ordinance that banned categories C and D jets — which include Gulfstreams and Citations — in response to concerns of residents that a plane will one day overshoot the runway and crash into homes that sit just 300 feet away. The ordinance came after negotiations stalled between City Hall and the FAA over proposed runway safety measures, including installing a series of concrete beds that would give way under the weight of an aircraft.

The FAA subsequently filed for an injunction just before the ban was set to go into effect. The matter has gone through various legal channels since then.

Most recently the FAA’s associate administrator for policy, planning and the environment upheld various aspects of the agency’s earlier findings regarding the jet ban, including that it unjustly discriminates against certain classes of aircraft. The associate administrator’s ruling represents the agency’s final decision, prompting City Hall to file for a federal appeal.

There are no negotiations currently taking place between the FAA and City Hall, but the agency’s spokesman Ian Gregor said that federal officials remain ready and willing to institute any of the proposals if asked.

A report on the AOPA’s Web site states that the association supports the FAA ruling that City Hall has no authority to ban jets at the airport. The association’s concern is that the case would set a dangerous precedent allowing local governments to ban certain types of operations at airports, the report stated.

“AOPA will bring a national perspective to this most critical issue,” Bill Dunn, the AOPA vice president of local airport advocacy, said in the report. “The outcome of this case could affect every publicly funded airport in the United States.”