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Flight Reliability

F9 4420 · Frontier Airlines

Hartford → San Juan (BDL–SJU)

36
Bring Snacks
WanderNerd Reliability Score
61%
Arrive within 15 minutes
28 min
Average arrival delay
3.1%
Cancelled
1 min
Median arrival delay

Based on 193 historical flights. Data through May 2026.

What the data says

The 12–3 PM departure wins.

F9 4420 departing between 12–3 PM arrived on time 84% of the time, versus 56% between 6–9 AM.

Sunday scaries are real for this one.

F9 4420 arrived on time 70% of the time on Fridays and just 50% on Sundays. That gap is worth planning around.

A bit behind the BDL–SJU route.

F9 4420 arrived on time 61% of the time, versus 65% across the BDL–SJU route.

Lagging the Frontier Airlines network.

F9 4420 arrived on time 61% of the time, versus 73% across the Frontier Airlines network.

The breakdown

On-time by weekday
  • Mon65%(23 flights)
  • Tue59%(22 flights)
  • Wed65%(26 flights)
  • Thu56%(27 flights)
  • Fri70%(27 flights)
  • Sat64%(28 flights)
  • Sun50%(28 flights)
On-time by departure window
  • 6–9 AM56%(48 flights)
  • 9 AM–12 PM57%(91 flights)
  • 12–3 PM84%(19 flights)
  • 3–6 PM73%(11 flights)
  • 6–9 PM67%(12 flights)
On-time trend by month
77%
May

Jun 57% → May 77% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202557%23
July 202546%22
August 202553%17
December 202590%20
January 202664%11
March 202663%16
April 202641%29
May 202677%30
Departures on time
67%
Diverted
3.1%
Flights flown
181
Months covered
11

Same route, other flights

Keep nerding

Based on 193 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.