An elderly man plunged 40 metres to his death while his traumatised workmate was left dangling from a safety harness after the collapse of a work platform at the rear of a Sydney building. The two subcontractors involved in the plunge had been hired to do maintenance work at the Maroubra Seals Sports and Community Club and were standing on a gantry at the Marine Parade building when one side gave way just before 2pm (AEDT) on Tuesday.