Hertz Joins Japan Airlines Frequent Flyer Program. The Hertz Corporation, the world's largest rental car company has joined the frequent flyer program of Japan Airlines. Effective August 1, 1998, members of the program will be eligible to earn 300 frequent flyer miles with each Hertz rental made in conjunction with travel on Japan Airlines only. Qualifying rentals must be reserved in advance using designated Japan Airlines frequent flyer discount rates, and take place at participating Hertz corporate locations worldwide within 24 hours of travel on a Japan Airlines flight. Rentals that involve tour packages, travel industry discounts, frequent flyer awards, or any other discounted rates are not eligible for credit.