This is a Sources Sought notice for market research to identify potential sources capable of providing production, engineering, and logistics support for the Low Probability of Intercept Altimeter (LPIA) program, including the R/T-1805/APN Receiver/Transmitter units and associated software. The anticipated contract type is an Indefinite Delivery Indefinite Quantity (IDIQ), with the incumbent contract held by BAE Systems ending in May 2026. The LPIA is a radar altimeter used across multiple military services, operating in the 4200 MHz to 4400 MHz band, and serves as a form, fit, and enhanced function replacement for the AN/APN-194(V) family. Interested parties must demonstrate proven experience with radar altimeters, lifecycle logistics, and military aviation software, and should submit a capabilities statement by 4:00pm on 23 May 2026. No budget information or specific performance location is mentioned in the notice.