* Air China, China Southern join China Eastern in request
* China was first country to ground 737 MAX after Ethiopia crash
* Global aviation regulators to meet in Dallas on Thursday (Adds compensation requests from China Southern and China Eastern)
BEIJING, May 22 (Reuters) - China's three biggest airlines have requested compensation from U.S. planemaker Boeing Co for losses incurred by the grounding and delayed deliveries of 737 MAX jets, as regulators gather to discuss design changes for the troubled aircraft.
Chinese state television on Wednesday reported that Air China Ltd and China Southern Airlines Co Ltd have added their voices to a request from China Eastern Airlines Corp Ltd a day earlier.
China was the first country to ground the 737 MAX globally after a crash in Ethiopia killed 157 people in March, in the second such incident for Boeing's newest aircraft.
The compensation requests come as the U.S. Federal Aviation Administration hosts global regulators in Dallas on Thursday to review 737 MAX software and training proposals from Boeing before deciding whether and when to end the two-month grounding.
The International Air Transport Association has convened a meeting of airlines with grounded 737 MAX jets for the same day in Montreal.
Other carriers including Turkish Airlines, United Airlines, Ryanair and Flydubai have also asked Boeing for compensation.
(Reporting by Stella Qiu and Brenda Goh; Editing by Himani Sarkar and Christopher Cushing)