This is a Sources Sought notice for a potential future contract modification to update the APX-119 Digital Control Panel software on F-5N/F aircraft to improve pilot safety by reducing heads-down time. The planned modification would add the acquisition of four software loader kits and extend the contract's period of performance to Fiscal Year 2027. The government anticipates this is a sole-source requirement for the Original Equipment Manufacturer, Raytheon Technologies Corporation, due to proprietary design and limited data rights, but is seeking capability statements to identify any other potential sources. Capability statements are due by 18 May 2026 at 11:00 AM EDT and must be submitted via email to the specified contacts. The notice emphasizes this is for market research only and does not constitute a formal solicitation or commitment from the government.