Flight number record
F9 4315
Frontier Airlines · Atlanta to Los Angeles
- Route
- ATL → LAX
- Departs
- 10:30
- Flights
- 327
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s F9 4315, check with Frontier Airlines.
F9 4315 sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 5 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 327 flights, with a median arrival 3 minutes early.
The national on-time rate over the same period is 77.6%, so F9 4315 runs 5 points behind the country as a whole. Across a thousand flights that is about 51 extra late arrivals.
Key figures
On time
72.5%
Arrivals under 15 minutes late, of 320 completed flights
Avg delay
66 min
Across delayed arrivals only, not all flights
Cancelled
2.14%
National rate is 1.81%
1 hour+ late
9.7%
National rate is 8.1%
These figures cover 327 flights between July 2025 and June 2026. Beyond the headline rate, 9.7% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Schedule
When F9 4315 flies
F9 4315 flies ATL to LAX without a single fixed slot. Its most common scheduled departure was 10:30, used on 80 of 327 flights, with 10:35 (51 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 10:3080 flights24.5%
- Departs 10:3551 flights15.6%
Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 10:30 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and F9 4315 runs 12 points worse at 72.5%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
Against the route
F9 4315 next to ATL to LAX
Every carrier on ATL to LAX combined arrived on time 78.4% of the time across 5,021 flights, so F9 4315 is 6 points behind it. Frontier flew 521 flights on the same city pair under all its flight numbers, including this one, and those ran 69.6% on time. Across its whole network Frontier Airlines managed 73.2%, close to this flight's figure.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| F9 4315thin sample | 327 | 72.5% | 66 min | 2.14% | C |
| All Frontier Airlines on ATL–LAX | 521 | 69.6% | 63 min | 2.11% | C |
| All carriers on ATL–LAX | 5,021 | 78.4% | 63 min | 0.86% | B+ |
| Frontier Airlines, whole network | 205,332 | 73.2% | 84 min | 1.85% | C |
Across the year
F9 4315 quarter by quarter
F9 4315 did not run the same all year. Its best quarter was Oct–Dec 2025 at 80.3% on time and its weakest Jan–Mar 2026 at 67.4%, a swing of 13 points on roughly 82 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202569 flights75.0%
- Oct–Dec 202577 flights80.3%
- Jan–Mar 202690 flights67.4%
- Apr–Jun 202691 flights69.0%
Scale runs 60% to 85%. Rows with fewer than 30 flights show a dash.
By weekday, F9 4315 did best on Wednesday at 88.9% on time and worst on Friday at 62.5%. Each day rests on about 47 flights, so a gap of 26 points is worth noticing but could still narrow in another year.
Delay causes
Why F9 4315 runs late
One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 5,823 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 48%Late-arriving aircraft
- 43%Carrier
- 9%National Airspace System
48% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 5,823 reported delay minutes here, that single category outweighs weather by 48 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 5,823 delay minutes reported on F9 4315.
Cancellations sit at 2.14% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.7% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 1,947 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
Every one of the 327 flights under F9 4315 in the data flew ATL to LAX. The number was not reused on any other city pair, which makes this a clean record of one route.
One caution: this is a thin sample. 327 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking F9 4315
For a booking, F9 4315 is one of the weaker ways to fly ATL to LAX: 6 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.
Related
Where to go next
- ATL to LAX, every carrier and departure
- LAX to ATL, the return direction
- Delta Air Lines 895 on the same route87.1%
- Delta Air Lines 898 on the same route87.1%
- Delta Air Lines 501 on the same route86.4%
- Delta Air Lines 996 on the same route89.2%
- Delta Air Lines 500 on the same route76.9%
- Delta Air Lines 753 on the same route84.8%
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- Los Angeles International (LAX) delay statistics
- Frontier Airlines on-time record
- Every Frontier Airlines flight number with a record
- The most and least reliable flight numbers in the US
- Why the first flight of the morning is statistically safest
A flight number here means Frontier Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.