About 21% Starlink odds, weighted to recent UA1721 flights. A firm answer comes about 2 days before departure, once the aircraft is assigned.
Based on 162 recent flights; Starlink found in 2 of 6 Wi-Fi checks since Feb 28, 2026 (last N27404, Nov 1, 2026).
Aircraft seen on UA1721: Boeing 737 MAX 9, Boeing 757-300.