A Palestinian guerrilla flying a motor-driven, glider-like device crossed the Israeli border from southern Lebanon last night, but was captured in the western Galilee after he was discovered by a member of a kibbutz near where he landed.

Another, identical aircraft crash-landed in the Christian enclave of southern Lebanon while trying to cross the border. Its pilot was captured by the Israeli-supported militia of Maj. Saad Haddad.

It was the first time Palestinian guerrillas had used gliders to infiltrate the heavily patrolled Israeli border. Last July, a cross-border attempt was made in a gas-filled balloon, which crashed in southern Lebanon.

The Iraqi-backed Arab Liberation Front said today in a statement from Beirut that two of its gliders had crossed the Israeli border and bombed Israeli positions. It identified the men as belonging to one of its Air Force units and the target area as near an oil refinery northeast of Haifa. The group is one of several guerrilla organizations opposed to a negotiated peace with Israel.

The Israel Army command said one of the gliders landed near Kibbutz Afek, in the western Galilee, but was discovered by a kibbutz member who heard its small engine.

Army officials said the aircraft resembled a sport hang-glider, but had a primitive seat and a small, 30-horsepower engine. An Army spokesman described its wingspan as about 14 feet.

Authorities said the pilot walked to a cooperative farm about 15 miles south of the border, where he encountered one of the residents and asked the man for clothing.

The Israeli, who said he had been walking to Carmiel, struck up a conversation in Arabic with the guerrilla, and the two walked together for several miles.

In an interview on Israeli radio, the Israeli, who was not identified, said he fell once in the darkness and the guerrilla helped him up. The Israeli said that at one point they became lost and that he suggested the two steal a car to enable the guerrilla to get to whatever destination he had in mind.

"All I want to do is cross the border" to Lebanon, the Israeli quoted the guerrilla as saying. He said that when the two finally stopped a passing car, he asked the guerrilla for his Kalashnikov assault rifle and that the guerrilla willingly gave it to him.

At that point, they parted, the Israeli leaving in the car and the guerrilla walking into the darkness. The Israeli alerted the border police.

The pilot, meanwhile, walked to the nearby Arab village of Tamra and took an Israeli Arab family hostage, while border police and Israeli troops surrounded the house. Early this morning a Druze border policeman and an Israeli soldier burst into the house and seized the guerrilla without a struggle, authorities said.

The second glider crashed north of Rosh Naqura, inside Lebanon. Its pilot was caught by Haddad's forces and turned over to the Israeli Army.

Police said the pilots both were equipped with small arms and hand grenades and had infiltrated to conduct terrorist operations inside Israel.