The abysmal test performance of a long-range Air Force missile has set back plans to arm jet fighters with the weapon, which would allow pilots to fire at ground targets from a safer, "standoff" distance.

Defense Department officials, frustrated with failure of the last five flight tests of the AGM130, have delayed production for two years and have threatened to scrap the $1.4 billion program, sources said.

An Air Force spokesman, Lt. Col. Jim Phillips, blamed the contractor, Rockwell International Corp., for chronically poor performance by the missile in tests since 1985.

Phillips said that, in several "live-fire" tests during the last 15 months, the missile swerved out of control after being fired from a plane. Earlier, the rocket motor attached to the missile exploded during ground tests, he said.

Phillips traced the poor quality of the $250,000 missile under development by Rockwell to quality-control problems at the company's Duluth, Ga., plant.

A spokesman for Rockwell agreed with this assessment but defended the missile's overall design.

The missile, since its inception in 1982, was designed to supplement the GBU15 bomb in the initial stages of a war against targets such as bridges, railroads, and airports. Its expanded range is made possible by a 10 1/2-foot, 500-pound rocket motor.

It is one of several "standoff" missiles under development by the Air Force and Navy to enable pilots to fire at targets from a greater distance.