Within the year SSI was incorporated, it was appointed General Sales Agent of 2 off-line carriers, Pakistan International Airlines (PK) and Varig Brazilian Airlines (RG). On Nov. 1 1969, Pakistan Airlines landed in the Philippines and began a flourishing online service between the Philippines, Pakistan and the Middle East, mainly catering to the Overseas Contract Worker market. During the India-Pakistan conflict in 2002, PK suspended several flights in Asia including Manila and from then on continued to operate in the Philippines as an off-line carrier.

From the mid-90's onwards, other airlines started to take notice of SSI's professional and impeccable reputation and performance, that it was also appointed GSA/PSA in the Philippines of these airlines: Cebu Pacific Air, Aeroperu, Mexicana de Aviacion, Hahn Air German Airlines, Aeromexico, Air Canada, Air Mauritius, Zest Air, AirPhil Express, Aerosvit, and Pacific Flier.

In 2010, Supersonic was appointed the Philippine wholesaler of Thai Airways' Royal Orchid Holidays, TAM Brazilian Airlines and China Eastern Airlines.

SSI maintains offices for all the airlines it represents with well-trained frontline staff to handle reservations & ticketing. Dedicated sales & marketing managers and account executives are engaged to handle daily personalized servicing of accounts, develop sales/marketing strategies to effectively promote the airlines and the destinations they serve. A tours department has also been set up to create and promote package tours in combination with special fares of the airlines represented.