Flight

SWA3521 15 Apr 2026

SWA3521, operated by Southwest Airlines, on 15 Apr 2026: Chicago Midway International (KMDW) to Seattle Tacoma International (KSEA). Scheduled and actual times are local to each airport (hover for UTC).

← 14 Apr 2026All SWA3521 flights16 Apr 2026 →

Flight

PlaneTrack receiver network
RouteKMDW CHICAGO MIDWAY INTERNATIONAL → KSEA SEATTLE TACOMA INTERNATIONAL
StatusCompleted (receiver network)
First seen airborne10:39 CDT
Last seen12:40 PDT
Duration4h 00m
AircraftN8855Q
Max altitude38,000 ft
Distance tracked1,502 nm

Punctuality, last 30 days

Flights6
On time4 (67%)
Average delay-203 min
Worst delay+81 min

In the last 30 days SWA3521 departed on time (within 15 minutes) on 4 of 6 flights (67%), with an average departure delay of -203 min and a worst delay of +81 min.

SWA3521 flight history Full history CSV API access

Schedule, departure and arrival times from the FAA SWIM feed; aircraft, altitude and distance from the PlaneTrack receiver network. On time means a departure within 15 minutes of schedule.