They're calling it the "straphangers' revolt," but amid the usual black humor about urban breakdown in the Big Apple, there was a jolt of future shock.

At 8:45 a.m. Tuesday, 1,500 passengers crammed into the graffiti-smeared cars of a Brooklyn subway were ordered off when the train developed mechanical problems. They boarded the next train, but three stops down the line they were told to get off because the second train was needed to push the first one.

Four hundred passengers balked, according to the New York City Transit Authority. Ten police officers were brought to persuade them, but enraged riders began to chant, "No! No! No! We won't go!"

They refused to budge for an hour and a half, during which transit officials were forced to empty a third train and divert it to haul off the broken-down one. Thousands of rush-hour passengers were delayed along the Flatbush Avenue line.

In a similar incident last month, 80 riders refused to evacuate a crippled train at West 34th Street in Manhattan. A furious conductor hauled them off to a repair yard on the Lower East Side while shouting obscenities into the public address system, according to several passengers. The conductor later was fired, although he contended that the riders, not he, were abusive.

"It's New Yorkers saying, 'I'm angry and I'm not going to take it anymore,' " said City Council President Carol Bellamy. "It's a living symbol of the fact that service is so lousy. We can put up with a lot, but this system is so bad even New Yorkers can't put up with it."

More than its gridlocked streets, its skyscraper-choked air, its deafening noise and trampling crowds, this city's 230-mile subway system, the largest mass-transit complex in the nation, has become the symbol of urban chaos and decay.

Faced with filthy cars, urine-spattered stations, rotten tracks, stuck doors, broken lights and air-conditioning systems, rising crime and a rash of fires and derailments, New York's 3.6 million subway riders simply are fed up.

"Miserable and intolerable," said Mayor Edward I. Koch.

Asked to explain the passenger rebellions, spokesmen for the transit authority hardly bother to come to its defense. "I can understand the frustration," said spokesman Donna Evans of Tuesday's 400-rider revolt. "Service on the Flatbush Avenue line is not the best. In fact, service throughout the system is not the best."

Are other lines better than Flatbush, she was asked. "No, everything's equally bad," she said with a sigh.

In the past year there have been 61,000 train delays, twice as many as 10 years ago. More than a quarter of the trains ran more than four minutes late. And at least 10,000 orders for spare parts and supplies were months behind because of computer overload.

Last year, after trains repeatedly derailed, 500 trouble spots were "red-tagged" where trains were forced to slow to a crawl. A transit authority consultant said a third of the motormen drove "like cowboys," slamming on brakes and occasionally jumping trains from the tracks.

"We've had years and years of what I call the three M's," Bellamy said. "Lack of money, lack of maintenance and lack of management."

The problems were aggravated by the city's fiscal crisis in the 1970s and an early-retirement program that emptied the system of skilled workers. Although a five-year, $6.3 billion capital program is under way, many more billions and major management changes are needed before services will improve, officials say.

In 1982, ridership fell below 1 billion for the first time since 1917. Last year, there were 22,004 citizen complaints. So high is the level of anger that Metropolitan Transportation Authority chief Robert Kiley told a New York newspaper when he was appointed last year that his predecessor was forced to wear a flak jacket after two attempts on his life and numerous threats. Kiley said he would require a round-the-clock police guard at his residence.

In 1983, 13,596 felonies were committed on New York subways, more than the entire criminal record of Knoxville, Tenn., and Madison, Wis., and up from 10,890 five years ago. Transit police issue 300,000 citations a year to citizens who try to evade the 90-cent fare. The system suffered more than 4,000 fires this year, nearly 700 of them serious.

At one point, German shepherd attack dogs tried to stop vandalism and graffiti in storage yards, but to no avail. The transit authority this month found 80 percent of its cars marred by graffiti. A July survey by the Straphangers Campaign, a citizens' group, found that one of four subway cars had broken doors, bad lighting or missing maps.

When Kiley sought to hire Philadelphia's transit chief, David Gunn, to run the bus and subway system, Gunn at first said he "wouldn't touch" the job, calling it "a suicide mission." Gunn earlier had characterized New York's subway system as "closer to death than it is to a tolerable life" because of years of neglect.

Gunn eventually accepted the $140,000-a-year job for "the challenge." By comparison, New York Gov. Mario M. Cuomo makes $100,000 a year and Koch makes $110,000.

Gunn and Kiley have fought an entrenched civil service system under which only about 300 of 49,000 employes can be fired, despite major personnel problems. A recent survey found that only 100 of 6,400 maintenance employes were qualified to read electrical prints.

Although the subways are controlled by an independent authority, the mayor, the governor and other politicians exercise some influence, and the state of the system has become a major political issue throughout the city.

In Brooklyn, a borough not known for the reticence of its inhabitants, state Sen. Joseph G. Montalto came up with a new campaign gimmick last month: handing out pre-addressed transit authority complaint forms to citizens at subway stops. As a result, complaints on the Flatbush Avenue line jumped from 496 in September to 780 in October.