Picture, Van Ness station fans will be used to equalize pressure as trains arrive. By Craig Herndon -- The Washington Post

When is my subway station going to open?

That question is particularly frustrating for people who look out the window to discover that the years of jackhammers and dump trucks and construction work appear to be over for their neighborhood Metro line -- but that the trains aren't running.

The answer is more elusive than ever for the uncompleted 64 miles and 42 unopened stations of the Metro system.Politics, the availability of money and some unfortunate planning all are playing roles in determining the expansion schedule.

That is the situation now on the next section scheduled to open -- the two-mile Red Line extension on Connecticut Avenue west of Rock Creek Park. There, to all outward appearances, the Metro construction crews have gone home after years of tearing up streets. That line now is scheduled to open in April or May of 1982. A year ago it was supposed to open this November. Three years ago it was supposed to open this July.

Despite the finished look at street level, much work remains to be done underground on the three stations along that line: Woodley Park-Zoo, Cleveland Park and Van Ness-UDC. In addition, track still must be laid on part of the extension of the Red Line from Dupont Circle. Wiring is needed and the signal system must be installed and tested.

The biggest short-term problem is the fact that Metro does not have enough subway cars. This problem controls the future opening dates not only of the Van Ness extension but also of the Blue Line addition from National Airport to Huntington through Alexandria, which is scheduled to open severel months afterward.

Metro needs all of the 300 cars it owns to operate the 37-mile system it has today and must have 308 cars to open to Van Ness and 328 to open to Huntington. The first of 94 new cars on order are not expected to arrive before the end of this year, five to six months later than originally scheduled.

The manufacturer, Breda Construzioni of Italy, ran into delays when a giant press it needed to make the aluminum panels for the sides of the cars broke down. The Metro board could have ordered the cars earlier than it did, but financial and political problems caused procrastination there, and there was no cushion.

When the cars arrive, they will have to be tested, but the Metro board removed a test track from the construction plan a few years back to save money. The result is that the Huntington line will be used to test new cars until a test track is built.

"We're really paying the piper for having taken the test track out of the program and for not ordering the cars sooner," said John S. Egbart, Metro's assistant general manager for design and construction.

Despite those difficulties, opening dates for 25 more miles of the system can confidently be predicted, give or take a few months. Dates are less certain for the remaining 39 miles, but completion in 1991 or 1992 for the planned 101-mile system is considered possible by Metro construction officials and others familiar with the program. The official schedule shows completion early in 1990.

Egbert, who is busy on a new official schedule, is unwilling to predict dates beyond those 25 miles, because of two factors.

First, he does not know how much money will be available from the new Reagan administration, so the size of annual construction packages in unknown. r

Second, each annual package must incorporate a new political fact: Maryland and Virginia, under the threat of losing District of Columbia money that is available for suburban construction, recently promised the D.C. government that the mid-city Green Line -- once last on the construction list -- now will share priority status with suburban projects. That inevitably means that some suburban projects will have to slip.

"We're trying to minimize delays for all three parties," Egbert said.