ASA521 is operated by ALASKA AIRLINES INC between Norman Y. Mineta San Jose International Airport (KSJC) and Seattle Tacoma International Airport (KSEA). The flight is most often flown by a BOEING Boeing 737-900. Typical block time is 1h 52m. SkyMeter has observed 90 legs of this flight number via ADS-B.

✈
FLIGHTS
90
last 90 days
⏱
AVG DURATION
1h 52m
tracked time
📅
SERVICE PERIOD
5/27/2025 → 8/13/2026
first → last seen
🗺
ROUTES / TYPES
7 / 4
city pairs · airframes
⚠
INCIDENT RATE
0.0%
0 flagged

Routes flown

By count · last 90 days

5
KSJC → KSEA
54
avg 1h 56m · Norman Y. Mineta San Jose → Seattle Tacoma
KSEA → KSJC
20
avg 1h 51m · Seattle Tacoma → Norman Y. Mineta San Jose
US-2788 → KSEA
1
avg 1h 30m · Santa Clara Valley → Seattle Tacoma
CA33 → KSJC
1
avg 6m · County Medical Center Heliport → Norman Y. Mineta San Jose
WN93 → KSEA
1
avg 11m · Park 90 Heliport → Seattle Tacoma

Aircraft types

Equipment used on this number

4
B739 BOEING Boeing 737-900
50
B39M BOEING Boeing 737 MAX 9
38
B738 BOEING Boeing 737-800
11
B38M BOEING Boeing 737 MAX 8
4

Safety profile

Flagged flights · last 90 days

Go-arounds
0
Unstable approach
0
Rejected TO
0
Stall warnings
0
Overspeeds
0
Runway excursion
0
Counts represent flights with at least one occurrence of each flag, not the total event count. See /incidents for individual events.

Recent flights

Newest 30 operations of ASA521

30
N408ASBOEING Boeing 737-900
→
8/13/2026
1h 47m
No alerts
Replay Analysis
N453ASBOEING Boeing 737-900
→
8/11/2026
1h 58m
No alerts
Replay Analysis
N719ALBOEING Boeing 737 MAX 9
→
8/11/2026
28m
No alerts
Replay Analysis
N719ALBOEING Boeing 737 MAX 9
→
8/10/2026
1h 50m
No alerts
Replay Analysis
N719ALBOEING Boeing 737 MAX 9
→
8/10/2026
2h 18m
No alerts
Replay Analysis
N268AKBOEING Boeing 737-900
→
8/9/2026
2h 4m
No alerts
Replay Analysis
N548ASBOEING Boeing 737-800
→
8/8/2026
1h 57m
No alerts
Replay Analysis
N943AKBOEING Boeing 737 MAX 9
→
8/7/2026
1h 53m
No alerts
Replay Analysis
N278AKBOEING Boeing 737-900
→
8/6/2026
2h 0m
No alerts
Replay Analysis
N926AKBOEING Boeing 737 MAX 9
→
8/6/2026
25m
No alerts
Replay Analysis
N926AKBOEING Boeing 737 MAX 9
→
8/5/2026
1h 38m
No alerts
Replay Analysis
N926AKBOEING Boeing 737 MAX 9
→
8/5/2026
2h 4m
No alerts
Replay Analysis
N805AKBOEING Boeing 737 MAX 8
→
8/4/2026
1h 55m
No alerts
Replay Analysis
N985AKBOEING Boeing 737 MAX 9
→
8/3/2026
2h 8m
No alerts
Replay Analysis
N409ASBOEING Boeing 737-900
→
8/2/2026
1h 58m
No alerts
Replay Analysis
N274AKBOEING Boeing 737-900
→
8/1/2026
1h 30m
No alerts
Replay Analysis
N926AKBOEING Boeing 737 MAX 9
→
7/31/2026
1h 47m
No alerts
Replay Analysis
N273AKBOEING Boeing 737-900
→
7/30/2026
1h 51m
No alerts
Replay Analysis
N260AKBOEING Boeing 737-900
→
7/29/2026
2h 0m
No alerts
Replay Analysis
N272AKBOEING Boeing 737-900
→
7/28/2026
1h 58m
No alerts
Replay Analysis
N975AKBOEING Boeing 737 MAX 9
→
7/27/2026
1h 53m
No alerts
Replay Analysis
N967AKBOEING Boeing 737 MAX 9
→
7/27/2026
33m
No alerts
Replay Analysis
N967AKBOEING Boeing 737 MAX 9
→
7/26/2026
1h 29m
No alerts
Replay Analysis
N967AKBOEING Boeing 737 MAX 9
→
7/26/2026
2h 3m
No alerts
Replay Analysis
N935AKBOEING Boeing 737 MAX 9
→
7/25/2026
1h 46m
No alerts
Replay Analysis
N920AKBOEING Boeing 737 MAX 9
→
7/24/2026
1h 49m
No alerts
Replay Analysis
N556ASBOEING Boeing 737-800
→
7/24/2026
28m
No alerts
Replay Analysis
N556ASBOEING Boeing 737-800
→
7/23/2026
2h 21m
No alerts
Replay Analysis
N556ASBOEING Boeing 737-800
→
7/23/2026
2h 49m
No alerts
Replay Analysis
N263AKBOEING Boeing 737-900
→
7/23/2026
14m
No alerts
Replay Analysis
© SkyMeter · All flight data subject to ODbL attribution · Tracked: 90-day window