CAPE CANAVERAL, Fla. (AP) _ General Dynamics Corp., already shrunken as a result of reduced defense spending, struggled Friday to overcome the latest setback in one of its three surviving businesses: space.

A malfunction by a General Dynamics rocket Thursday left a Navy satellite orbiting 5,000 miles too low. It was the company's third failure in eight launches.

Company officials offered no excuses and promised to solve the problem and get on with launching Atlas rockets. They said the same thing the last time one of their rockets failed, in August, and the previous time, in April 1991.

The way some analysts see it, time is running out.

''There's a lot of technical risk'' in launching rockets, said Kent Newcomb, a defense industry analyst for A.G. Edwards in St. Louis. ''On the other hand, they're supposed to work right. You only get one shot at it.''

But another industry analyst, Wolfgang Demisch of UBS Securities Inc. in New York, said the financial impact of the failed launch should be relatively minor.

Michael Wynne, president of General Dynamics' San Diego-based Space Systems Division, said Thursday's failure was a setback, but the company would move forward.

''It's a disappointment, but we have contractual launches out through 1997, which we intend to meet,'' Wynne said.

Atlas flights, however, are on hold until the company can determine why the first-stage booster didn't provide enough thrust Thursday. The next launch is scheduled for May.

Repercussions even were felt by competing rocket maker McDonnell Douglas. Late Friday afternoon, the Air Force delayed its planned launch of a McDonnell Douglas Delta rocket from Saturday to Sunday so program managers could review engine data from the failed Atlas launch. The engines in both rockets, while different, are made by the same company - Rocketdyne.

General Dynamics' last investigation into a failed launch lasted seven months. Both the 1991 and 1992 failures were traced to stuck engine valves, which worked this time.

In those launches, the rockets had to be blown up over the Atlantic along with their payloads, multimillion-dollar communications satellites. This time, the satellite reached space.

On-board thrusters may be able to boost the satellite to make the spacecraft some use to the Navy, said Ron Swanson, general manager of satellite maker Hughes Space and Communications Co. But there isn't enough fuel to put the satellite where it was supposed to be, preventing its full use, he said.

Swanson said the satellite is in a safe orbit now and there is time to consider all the options.

The Navy will be reimbursed, Swanson said. The entire mission - rocket, satellite and insurance - cost $138 million.

The Navy relies on nine satellites for ship-to-shore communications, but the spacecraft need to be replaced, said Capt. Edward Enterline, director of Navy Space Systems Division.

General Dynamics can ill afford to lose business. The space division lost $41 million last year and $70 million in 1991. The Falls Church, Va.,-based corporation as a whole, however, had net earnings of $815 million in 1992 and $505 million in 1991.

The othehr remaining core businesses at General Dynamics are armored vehicles and nuclear submarines. Missile, tactical military aircraft and other units were sold to strengthen the company and deal with ''new military spending realities,'' said spokesman Alvin Spivak.

The corporation's annual revenues are about $3.5 billion, down from $10 billion two years ago before the consolidation. Its work force is 30,000, down from 98,000. About 4,200 work in the space division.

General Dynamics stock closed at $115 a share, down $1.75, in trading Friday on the New York Stock Exchange.