On 3 September 1950, Sergeant Bill Harrop was forced down behind enemy lines and executed by the North Koreans. Six days later, Spence was killed when his Mustang failed to pull out of a dive during a napalm attack on Angang-ni. His death was a serious blow to the squadron, and the RAAF despatched Cresswell on his third tour as commanding officer to replace him. Cresswell arrived at Iwakuni on 17 September and set about restoring morale, undertaking four sorties on his first day of operations three days later. MacArthur had meanwhile launched an amphibious landing behind North Korean lines at Inchon on 15 September, forcing the communists to retreat from the Pusan Perimeter. No. 77 Squadron was transferred from Iwakuni to Pohang, South Korea, on 12 October, to support UN forces advancing northwards. On 20 October, the squadron became a component of the RAAF's newly established No. 91 (Composite) Wing, which also included No. 391 (Base) Squadron, No. 491 (Maintenance) Squadron, and No. 30 Communications Flight, formerly the No. 77 Squadron Communications Flight. The wing and all units except No. 77 Squadron, which came under the operational control of the US 35th Fighter-Interceptor Group, were headquartered at Iwakuni.