Flight number record

OO 5421

SkyWest Airlines · Denver to Lubbock

Route: DEN → LBB
Departs: 13:50
Flights: 365
Period: September 2025 to August 2026

Historical statistics for September 2025 to August 2026, not live status. For today’s OO 5421, check with SkyWest Airlines. SkyWest Airlines flies under contract for larger airlines, so a ticket for this flight may show a different airline code and number.

OO 5421 lands a B+, 2 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 365 flights, with a median arrival 9 minutes early.

On time

79.2%

Arrivals under 15 minutes late, of 361 completed flights

Avg delay

96 min

Across delayed arrivals only, not all flights

Cancelled

0.55%

National rate is 1.89%

1 hour+ late

11.1%

National rate is 8.3%

These figures cover 365 flights between September 2025 and August 2026. Beyond the headline rate, 11.1% of arrivals land a full hour or more behind schedule, against 8.3% nationally.

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Schedule

When OO 5421 flies

OO 5421 flies DEN to LBB without a single fixed slot. Its most common scheduled departure was 13:50, used on 85 of 365 flights, with 13:55 (70 flights) and 14:10 (47 flights) next.

Departs 13:5085 flights23.3%
Departs 13:5570 flights19.2%
Departs 14:1047 flights12.9%

Scale runs 0% to 100%.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 13:50 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.3%, and OO 5421 runs level with that at 79.2%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

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Against the route

OO 5421 next to DEN to LBB

Every carrier on DEN to LBB combined arrived on time 71.4% of the time across 980 flights, so OO 5421 is 8 points ahead of it. SkyWest flew 700 flights on the same city pair under all its flight numbers, including this one, and those ran 75.8% on time. Across its whole network SkyWest Airlines managed 78.7%, close to this flight's figure.

OO 5421 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 5421	365	79.2%	96 min	0.55%	B+
All SkyWest Airlines on DEN–LBB	700	75.8%	101 min	1.43%	B
All carriers on DEN–LBB	980	71.4%	89 min	1.63%	C
SkyWest Airlines, whole network	855,406	78.7%	88 min	1.79%	B

Across the year

OO 5421 quarter by quarter

OO 5421 did not run the same all year. Its best quarter was Jul–Sep 2025 at 86.7% on time and its weakest Jan–Mar 2026 at 70.1%, a swing of 17 points on roughly 73 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 202530 flights86.7%
Oct–Dec 202592 flights84.8%
Jan–Mar 202690 flights70.1%
Apr–Jun 202691 flights75.8%
Jul–Sep 202662 flights85.2%

Scale runs 60% to 90%.

By weekday, OO 5421 ranged from 74.5% on Friday to 84.6% on Tuesday. With about 52 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.

Arrival by arrival

How late OO 5421 runs when it is late

OO 5421 often beats the schedule: 121 of 361 completed flights, 34%, arrived 15 minutes or more early. When OO 5421 is late it tends to be very late: 40 of its 75 late arrivals were an hour or more behind, and 16 were two hours or more.

15+ min early121 flights33.5%
Within 15 min165 flights45.7%
15–29 min late14 flights3.9%
30–59 min late21 flights5.8%
1–2 hours late24 flights6.6%
2+ hours late16 flights4.4%

Scale runs 0% to 100%.

Share of 361 completed flights by arrival against schedule.

10 of 77 late departures made up the time and arrived on time, 13% of them. 8 flights left on time and still arrived late.

The worst days

Worst days for OO 5421

The latest arrival of the period was on 16 January 2026, 17 hours 57 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The five worst days are spread across January, November, June, February and August, with no single month standing out.

The latest arrivals of OO 5421 in the period
Date	Arrived late by	Largest filed cause
16 January 2026	17 hours 57 minutes	Late-arriving aircraft
29 November 2025	7 hours 32 minutes	Late-arriving aircraft
24 June 2026	5 hours 18 minutes	Carrier
17 February 2026	4 hours 32 minutes	National Airspace System
22 August 2026	3 hours 45 minutes	Carrier

Delay causes

Why OO 5421 runs late

Late-arriving aircraft accounts for 56% of the 7,213 delay minutes carriers reported here, and the remaining four split what is left.

Late-arriving aircraft
56%
Carrier
29%
National Airspace System
9%
Extreme weather
6%

56% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 7,213 reported delay minutes here, that single category outweighs weather by 9 to one. The split is drawn from 7,213 delay minutes reported on OO 5421.

Cancellations are rare at 0.55%, below the national 1.89% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

11.1% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.

Every one of the 365 flights under OO 5421 in the data flew DEN to LBB. 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. 365 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 OO 5421

For a booking, read OO 5421 as 79.2% on time with 0.55% cancelled over 365 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

A flight number here means SkyWest 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, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures