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Flight Reliability

F9 3665 · Frontier Airlines

Denver → Sacramento (DEN–SMF)

85
Pretty Reliable
WanderNerd Reliability Score
82%
Arrive within 15 minutes
1 min
Average arrival delay
0.6%
Cancelled
8 min early
Median arrival delay

Based on 164 historical flights. Data through May 2026.

What the data says

Friday is doing you no favors.

F9 3665 arrived on time 91% of the time on Thursdays and just 75% on Fridays. That gap is worth planning around.

Better than the DEN–SMF route average.

F9 3665 arrived on time 82% of the time, versus 74% across the DEN–SMF route.

Better than the Frontier Airlines network average.

F9 3665 arrived on time 82% of the time, versus 73% across the Frontier Airlines network.

Trending in the right direction.

F9 3665 arrived on time 87% of the time over the last three months in the data, compared with 76% in the three months before that.

The breakdown

On-time by weekday
  • Mon84%(49 flights)
  • Tue—(2 flights)
  • Wed—(5 flights)
  • Thu91%(21 flights)
  • Fri75%(48 flights)
  • Sat—(7 flights)
  • Sun80%(30 flights)
On-time by departure window
  • 9 AM–12 PM82%(161 flights)
  • 3–6 PM—(1 flights)
On-time trend by month
94%
May

Aug 100% → May 94% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
August 2025100%13
September 202571%17
October 202579%14
November 202575%16
December 202567%15
January 202686%14
February 202675%12
March 202682%17
April 202685%13
May 202694%16
Departures on time
80%
Diverted
0.6%
Flights flown
162
Months covered
12

Same route, other flights

Keep nerding

Based on 164 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.