WASHINGTON (AP) _ Defense Secretary Dick Cheney declared an ''airlift emergency'' Friday and ordered airlines to provide more planes to help ferry supplies and equipment to the Middle East. Officials said 17 planes would be pressed into service.

Though Cheney's order covered 181 planes, the Military Airlift Command said it had no plans to use that many.

The action puts into effect the second stage of a longstanding agreement between the government and the airline industry that commercial jets could be turned over to military service in the event of an emergency.

On Aug. 17, Cheney activated the first stage of the Civil Reserve Air Fleet plan, under which the government charters commercial aircraft. The agreement obligates the airlines to provide the planes within 24 hours.

The August action marked the first time the plan had been put into effect since it was drawn up in 1952.

Twenty-nine planes were provided in the first-stage activation. Of those, 28 are still in service, mostly flying personnel to the theater of war.

At Scott Air Force Base, Ill., home of the Military Airlift Command, Chief Master Sgt. Kim Lobring said the planes taken over in August have flown 1,915 missions.

Lobring, chief spokesman for the command, said the military needs cargo versions of Boeing 747s, 727s and 707s; McDonnell Douglas DC-10s and DC-8s and the Lockheed L-100, the civilian version of the C-130 workhorse military transport.

Since only cargo planes are wanted, ''There should be no disruption of the passenger traffic,'' the sergeant said.

Cheney said the Military Airlift Command, which is in charge of air deliveries of war supplies, would ''use only airlift aircraft needed and would attempt to minimize disruption to regularly scheduled passenger service of participating airlines.''

The Pentagon has declined to identify the airlines that are party to the agreement.

In Minneapolis, Northwest Airlines said Friday it was adding one Boeing 747 freighter to the five 747s - three passenger planes and two freighters - now being provided to the government under the program.

In Chicago, United Air Lines spokesman Tony Molinaro said, ''We are participating.'' But he said United, at the request of the Defense Department, would withhold details.

Under the agreement, airlines agree to make available planes for charter if needed. In return, the Pentagon pays for certain modifications it needs in the planes, such as the addition of cargo tie-down points and stronger floors.

By a coincidence, Cheney acted the very evening that Eastern Airlines announced it was halting all flights at midnight. Eastern, which has been operating under protection of the bankruptcy laws for two years, will idle 155 aircraft of several types.

Airline spokeswoman Karen Ceremsak said she did not know if any Eastern planes would be part of the callup. Asked if the airline would offer them to the Defense Department, she said, ''We've got are hands full with other things, so I can't answer that right now.''

Pentagon officials said privately there was no connection between Eastern's announcement and Cheney's decision. The armed forces had asked Cheney to activate the second part of the airliner agreement a week ago, said one official, who spoke on condition of anonymity.