Continental Airlines unveiled a new bonus program yesterday that its officials said allows travelers for the first time to earn mileage credits toward free flights by renting cars and staying at hotels.

The new program, called TravelBank, lets participants earn mileage credits by renting cars from National Car Rental or by staying at Hilton Hotels, as well as by flying Continental and its associated airlines, New York Air and Texas International.

"We call this our fly, drive and sleep package," said Continental Vice Chairman George A. Warde yesterday.

The program is the latest in a plethora of airline promotions designed to lure the frequent flyer from the competition and from the haphazard picking of airlines by awarding free or reduced future travel to customers who collect enough segments, points, coupons or mileage on current flights.

Mileage collected in the new Continental program also can be redeemed for free Hilton hotel rooms and National car rentals.

Warde and New York Air President Michael E. Levine told a news conference here yesterday that each stay at a participating Hilton Hotel or Inn, each car rental from National, and each flight on New York Air would earn 1,000 miles credit, regardless of length of stay, rental or flight. Continental and Texas International flights count actual miles, regardless of the fare.

Awards start with a free three-day weekend car rental at 7,000 miles. At 20,000 miles, a traveler can take a free round-trip ticket on NYA; at 40,000 miles, the program awards a free round trip on Continental for U.S. or Mexico travel; 50,000 miles earns a free room for a week at a Hilton, and so on. A traveler who collects 120,000 miles can get two free first-class tickets to the South Pacific.