Flight number record

OO 4939

SkyWest Airlines · Midland to Phoenix

Route: MAF → PHX
Departs: 09:32
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s OO 4939, 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 4939 earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 3.4 hours. That rests on 365 flights, with a median arrival 15 minutes early.

Set against the rest of the country, OO 4939's record is 9 points better than the US average of 77.6%. That gap is worth roughly 86 fewer late arrivals for every thousand flights.

On time

86.2%

Arrivals under 15 minutes late, of 362 completed flights

Avg delay

201 min

Across delayed arrivals only, not all flights

Cancelled

0.82%

National rate is 1.81%

1 hour+ late

9.1%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. Beyond the headline rate, 9.1% 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 OO 4939 flies

OO 4939 flies MAF to PHX without a single fixed slot. Its most common scheduled departure was 09:32, used on 74 of 365 flights, with 09:30 (64 flights) and 06:48 (43 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 09:3274 flights20.3%
Departs 09:3064 flights17.5%
Departs 06:4843 flights11.8%

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 09:32 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and OO 4939 runs 2 points better at 86.2%. 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

OO 4939 next to MAF to PHX

Every carrier on MAF to PHX combined arrived on time 86.2% of the time across 366 flights, so OO 4939 is about level with it. Across its whole network SkyWest Airlines managed 79.0%, which this flight beats by 7 points.

OO 4939 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
OO 4939	365	86.2%	201 min	0.82%	A+
All SkyWest Airlines on MAF–PHX	365	86.2%	201 min	0.82%	A+
All carriers on MAF–PHX	366	86.2%	201 min	0.82%	A+
SkyWest Airlines, whole network	852,935	79.0%	88 min	1.77%	B

Across the year

OO 4939 quarter by quarter

Quarter by quarter OO 4939 held fairly steady: 83.7% in Jul–Sep 2025, 85.9% in Oct–Dec 2025, 87.4% in Jan–Mar 2026 and 87.9% in Apr–Jun 2026. A spread of 4 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights83.7%
Oct–Dec 202592 flights85.9%
Jan–Mar 202690 flights87.4%
Apr–Jun 202691 flights87.9%

Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, OO 4939 did best on Wednesday at 94.2% on time and worst on Monday at 78.8%. Each day rests on about 52 flights, so a gap of 15 points is worth noticing but could still narrow in another year.

Delay causes

Why OO 4939 runs late

One category carries most of the weight here. Carrier accounts for 60% of the 10,000 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.

Carrier
60%
Late-arriving aircraft
25%
Extreme weather
13%
National Airspace System
2%

Extreme weather accounts for 13% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.1 times the usual weather exposure. The split is drawn from 10,071 delay minutes reported on OO 4939.

Cancellations are rare at 0.82%, below the national 1.81% 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

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.1% 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.

The 581 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

Every one of the 365 flights under OO 4939 in the data flew MAF to PHX. 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 4939

For a booking, OO 4939 has one of the better records a US domestic flight can show: 86.2% on time and 0.82% cancelled. That is a base rate, not a promise about any single 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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures