According to Official Guinness Records,
The heaviest combined weight of aircraft pulled simultaneously is 474.72 tonnes (1,046,578 lb) and was achieved by the Hong Kong Community at Hong Kong International Airport in Hong Kong, China, on 17 March 2011. The aircraft pulled were a Boeing 747-400, an Airbus 330-343, an Airbus 300-200 and a Zlin Z-242 L. Over 200 participants joined forces to pull the aircraft over the required distance of 50 m (164 ft 0.5 in) in 2 min and 53 sec.
For a complete list of 2011 records, please visit 2011 Guinness Records in China.