NASA Ames Research Center (ARC) has a requirement for commercial aviation services in support of the Snow4Flow Earth Venture Suborbital-4 (EVS-4) mission, a NASA airborne mission to improve the ability to interpret ongoing and future changes in Northern Hemisphere glaciers. The requirement is for the provision, modification, and operation of a Basler BT-67 aircraft in a science configuration, including aircraft, crew, maintenance, and insurance (ACMI) services; engineering and aircraft modification support for integration of the Snow4Flow instrument suite; compliance with FAA/Transport Canada Civil Aviation airworthiness standards and the NASA airworthiness review process under NAII 7900.3; and check, transit, and science flights supporting three planned Snow4Flow Arctic campaigns (2027 through 2029) across Alaska, the Yukon Territory (Canada), Svalbard, Greenland, and the Canadian High Arctic, plus additional airborne science task orders as required. NASA anticipates award of a single firm-fixed-price (FFP) indefinite-delivery, indefinite-quantity (IDIQ) contract with a five (5) year ordering period, a six (6) month option to extend services, and task orders issued at pre-priced annual catalog rates. The first task order is anticipated to cover instrument integration support and the start of the 2027 Alaska Arctic campaign with a period of performance of 23 February 2027 through 2 March 2027. NASA/ARC intends to issue a sole source contract to acquire these services from ALCI Aviation Ltd., doing business as Enterprise Aviation Group, of Oshawa, Ontario, Canada, under the authority of 10 U.S.C. 3204(a)(1), as implemented by FAR 6.103-1, Only One Responsible Source. Market research determined that only the Basler BT-67 aircraft type can execute this mission in the remote arctic operating environment with the endurance required, that only two commercial operators offer the Basler BT-67 in a suitable science configuration, and that Enterprise Aviation Group is the only operator with aircraft availability that meets the mission schedule across the three years of Snow4Flow science flights. The Snow4Flow instrument package will be integrated and approved for flight on the Enterprise Aviation Group aircraft prior to the start of the ordering period, and award to another source would require the Government to duplicate integration and check flight costs and repeat airworthiness reviews that cannot be accomplished within the available seasonal flight window. The Government intends to acquire a commercial service using FAR Part 12. Interested organizations may submit their capabilities and qualifications to perform the effort electronically via email to Joshua Taggart at joshua.d.taggart@nasa.gov not later than 12:00 PM CDT on July 1, 2026. Such capabilities/qualifications will be evaluated solely for the purpose of determining whether to conduct this acquisition on a competitive basis. A determination by the Government not to compete this acquisition on …