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Delta Air Lines / RDU → AUS

DL 4921 on time

Delta Air Lines 4921: Raleigh to Austin at 7:00 a.m.; Austin to Raleigh at 10:07 a.m. (past 12 months). Figures below the title are for RDU → AUS, its busiest leg

On time
88%
238 flights · likely 83–91%
Cancelled
1.7%
of scheduled flights
Typical arrival
−15 min
median vs schedule
When late
+76 min
average delay
Similar flights
88%
DL, same route & hour

About 1 in 8 DL 4921 flights from Raleigh arrived 15+ minutes late, diverted or cancelled over the past year (12%); 1.7% were cancelled. The typical flight landed 15 minutes early.

DL 4921: RDU → AUS

Scheduled to leave Raleigh at 7:00 a.m. local time, operated by Endeavor Air as 9E 4921. Over the past year it arrived on time 88% of the time (238 flights), in line with other DL flights on the route at that hour (88%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Jan 2026: 85% on time (27 flights)85JanFeb 2026: 86% on time (28 flights)86FebMar 2026: 97% on time (31 flights)97MarApr 2026: 97% on time (29 flights)97AprMay 2026: 77% on time (31 flights)77MayJun 2026: 83% on time (30 flights)83JunJul 2026: 84% on time (31 flights)84JulAug 2026: 94% on time (31 flights)94Aug

By day of week

DayFlightsOn time
Monday3583%
Tuesday3497%
Wednesday3491%
Thursday3394%
Friday3482%
Saturday3488%
Sunday3479%

Why it was late

Airline (crew, maintenance, ops) 63%Air traffic & airport (NAS) 21%Late inbound plane 12%Severe weather 5%

All flights RDU → AUS · Connecting off DL 4921? Check the risk

DL 4921: AUS → RDU

Scheduled to leave Austin at 10:07 a.m. local time, operated by Endeavor Air as 9E 4921. Over the past year it arrived on time 84% of the time (177 flights), in line with other DL flights on the route at that hour (84%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Feb 2026: 82% on time (17 flights)82FebMar 2026: 90% on time (31 flights)90MarApr 2026: too few flights (12 flights)AprMay 2026: 76% on time (25 flights)76MayJun 2026: 80% on time (30 flights)80JunJul 2026: 84% on time (31 flights)84JulAug 2026: 94% on time (31 flights)94Aug

By day of week

DayFlightsOn time
Monday2580%
Tuesday2496%
Wednesday2479%
Thursday2692%
Friday2677%
Saturday2681%
Sunday2681%

Why it was late

Late inbound plane 70%Air traffic & airport (NAS) 18%Airline (crew, maintenance, ops) 12%

All flights AUS → RDU · Connecting off DL 4921? Check the risk

Questions

How often is DL 4921 from RDU to AUS late?

Delta Air Lines 4921 from Raleigh/Durham, NC to Austin, TX arrived 15 or more minutes late, was diverted or was cancelled on 12% of 238 scheduled flights between September 2025 and August 2026. 1.7% were cancelled.

How often is DL 4921 from AUS to RDU late?

Delta Air Lines 4921 from Austin, TX to Raleigh/Durham, NC arrived 15 or more minutes late, was diverted or was cancelled on 16% of 177 scheduled flights between September 2025 and August 2026. 0.0% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.