Renaming Washington National Airport in honor of former president Ronald Reagan {Close to Home, Jan. 11} could be a costly proposition, especially if proponents of the switch push for the full package and insist on changing the current "DCA" three-letter airport identifier to something like "RWR."

Such a redesignation would require changes in published airline schedules, computer programs, baggage tags, stationery, invoices . . . the whole nine yards. The costs to the airlines would run into the millions.

That explains why the Federal Aviation Administration, which is responsible for assigning airport identifiers, normally is reluctant to make such changes. The petitioner in each instance must submit "strong and documented justification, primarily concerning air safety." And that really isn't necessary in most cases.

Look at Chicago's O'Hare, the world's busiest airport. It was named for World War II hero Edward "Butch" O'Hare way back in 1949, but it still uses the "ORD" identifier it inherited from the airport it replaced, Orchard Field.

The country's second busiest airport, Atlanta's William B. Hartsfield International, named for a former near-career Atlanta mayor, gets along just fine with "ATL."

On the other hand, when New York's Idlewild Airport was renamed to honor John F. Kennedy in April 1964, it got a new identifier as well -- the now familiar JFK. It probably seemed a fitting tribute at the time to the murdered president to have his initials flown all over the globe, and if some people minded the additional expense, they wisely kept it to themselves.

Dulles International Airport also got its former "DIA" identifier changed but for a different reason. The FAA thought it was just a little too similar to nearby "DCA" and might even create safety problems. Say DIA and DCA together three times fast, and you can see the potential for confusion. So, erring on the side of caution, the identifier was changed to "IDA," and if former Secretary of State John Foster Dulles (under President Eisenhower) turned over in his grave, we'll never know about it.

Maryland, however, didn't fare as well when it changed the name of Baltimore Friendship Airport to Baltimore-Washington Airport. It wanted a "BWI" identifier to drive home the message that the airport could serve both metropolitan areas. But the FAA said no -- quite a few times -- although it was accused of conflict of interest because it operated both National and Dulles at the time and conceivably might not have been eager to encourage the competition. But despite the flak the FAA took, the last time I flew out of BWI, my baggage tag still read "BAL."

Having an airport named for a president wouldn't be a first for Washington. The privately owned Hoover Field (later Washington-Hoover) near the site of the Pentagon opened in 1926 and served as Washington's principal airport for many years. The catch is that the airport was named for Secretary of Commerce Herbert Hoover, who didn't become president until March 1929. And he didn't use Hoover or any other airport during his term of office.

If you want to stretch a point, Washington National also is named for a president. That is, it is named for a city that is named for a president. But that doesn't seem like quite the same thing, does it? -- John G. Leyden