ON TIMEBOARD

F9 3990 on time

Frontier Airlines 3990: Dallas to Detroit at 2:29 p.m. (past 12 months)

On time
76%
215 flights · likely 70–81%
Cancelled
1.4%
of scheduled flights
Typical arrival
−7 min
median vs schedule
When late
+73 min
average delay
Similar flights
74%
F9, same route & hour

About 1 in 4 F9 3990 flights from Dallas arrived 15+ minutes late, diverted or cancelled over the past year (24%); 1.4% were cancelled. The typical flight landed 7 minutes early.

F9 3990: DFW → DTW

Scheduled to leave Dallas at 2:29 p.m. local time. Over the past year it arrived on time 76% of the time (215 flights), in line with other F9 flights on the route at that hour (74%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: too few flights (13 flights)SepOct 2025: too few flights (3 flights)OctNov 2025: too few flights (8 flights)NovDec 2025: 89% on time (19 flights)89DecJan 2026: too few flights (12 flights)JanFeb 2026: too few flights (8 flights)FebMar 2026: 82% on time (17 flights)82MarApr 2026: 73% on time (15 flights)73AprMay 2026: 86% on time (28 flights)86MayJun 2026: 53% on time (30 flights)53JunJul 2026: 58% on time (31 flights)58JulAug 2026: 90% on time (31 flights)90Aug

By day of week

DayFlightsOn time
Monday3569%
Tuesday19—
Wednesday2075%
Thursday3667%
Friday3985%
Saturday2277%
Sunday4484%

Why it was late

Late inbound plane 50%Airline (crew, maintenance, ops) 29%Air traffic & airport (NAS) 21%Severe weather 1%

All flights DFW → DTW · Connecting off F9 3990? Check the risk

Questions

How often is F9 3990 from DFW to DTW late?

Frontier Airlines 3990 from Dallas/Fort Worth, TX to Detroit, MI arrived 15 or more minutes late, was diverted or was cancelled on 24% of 215 scheduled flights between September 2025 and August 2026. 1.4% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Frontier Airlines for today's flight. Method.