Singapore Airlines and Vietnam Airlines on Oct. 26 will launch a codeshare agreement, the carriers announced Tuesday. Singapore will place its code on Vietnam Airlines-operated flights between Singapore and Hanoi and Ho Chi Minh City in Vietnam. Vietnam Airlines will place its code on Singapore Airlines-operated flights between Singapore and Da Nang, Hanoi and Ho Chi Minh City. All flights are subject to regulatory approval, and flights will be available for purchase beginning Oct. 10.