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Flight Reliability

F9 1247 · Frontier Airlines

Grand Rapids → Denver (GRR–DEN)

84
Pretty Reliable
WanderNerd Reliability Score
76%
Arrive within 15 minutes
9 min
Average arrival delay
0%
Cancelled
10 min early
Median arrival delay

Based on 117 historical flights. Data through May 2026.

What the data says

The 3–6 PM departure wins.

F9 1247 departing between 3–6 PM arrived on time 92% of the time, versus 74% between 6–9 PM.

Monday comes out ahead.

A small edge: 77% on time on Mondays against 71% on Sundays.

A bit behind the GRR–DEN route.

F9 1247 arrived on time 76% of the time, versus 80% across the GRR–DEN route.

A bit ahead of the Frontier Airlines network.

F9 1247 arrived on time 76% of the time, versus 73% across the Frontier Airlines network.

The breakdown

On-time by weekday
  • Mon77%(34 flights)
  • Tue—(1 flights)
  • Wed75%(12 flights)
  • Thu—(6 flights)
  • Fri77%(34 flights)
  • Sat—(6 flights)
  • Sun71%(24 flights)
On-time by departure window
  • 3–6 PM92%(13 flights)
  • 6–9 PM74%(104 flights)
On-time trend by month
92%
May

Jun 65% → May 92% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202565%17
July 202559%17
August 202583%18
September 202575%12
October 202564%14
April 202690%10
May 202692%13
Departures on time
75%
Diverted
0%
Flights flown
117
Months covered
10

Same route, other flights

Keep nerding

Based on 117 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.