In 1976, Yao was promoted to Chief of Staff of the 66th Army and stationed in nearby Tianjin.[1] When the Great Tangshan earthquake occurred at 3 am, 28 July 1976, Yao was woken from sleep by violent shaking of the ground. Unsure where the epicenter of the quake was, he contacted all divisions of the 66th Army, but could not reach his own 197th Division.[1] He set out with two soldiers and drove toward Tangshan. Because a major bridge was destroyed in the quake, they had to abandon the car and cross by boat, and did not reach Tangshan until 11 am. He was the first military leader to arrive in Tangshan, and led his soldiers in the rescue effort. However, most of the people they dug out were already dead, and they only occasionally found survivors under the rubble.[1] Although Yao had fought in numerous battles in three wars, he described the Tangshan earthquake the most tragic experience in his life.[1]