ON TIMEBOARD
Delta Air Lines / BOS → JAX

DL 5597 on time

Delta Air Lines 5597: Boston to Jacksonville at 8:45 a.m.; Jacksonville to Boston at 12:24 p.m. (past 12 months). Figures below the title are for BOS → JAX, its busiest leg

On time
82%
175 flights · likely 76–87%
Cancelled
0.0%
of scheduled flights
Typical arrival
−8 min
median vs schedule
When late
+54 min
average delay
Similar flights
82%
DL, same route & hour

About 1 in 6 DL 5597 flights from Boston arrived 15+ minutes late, diverted or cancelled over the past year (18%); 0.0% were cancelled. The typical flight landed 8 minutes early.

DL 5597: BOS → JAX

Scheduled to leave Boston at 8:45 a.m. local time, operated by Republic Airways as YX 5597. Over the past year it arrived on time 82% of the time (175 flights), in line with other DL flights on the route at that hour (82%). Last seen in the data Aug 30, 2026.

Month by month

40%70%100%Dec 2025: too few flights (12 flights)DecJan 2026: too few flights (4 flights)JanMar 2026: 67% on time (24 flights)67MarApr 2026: 88% on time (26 flights)88AprMay 2026: 93% on time (29 flights)93MayJun 2026: 89% on time (28 flights)89JunJul 2026: 78% on time (27 flights)78JulAug 2026: 80% on time (25 flights)80Aug

By day of week

DayFlightsOn time
Monday2767%
Tuesday2789%
Wednesday2781%
Thursday2785%
Friday2479%
Saturday14—
Sunday2997%

Why it was late

Airline (crew, maintenance, ops) 43%Air traffic & airport (NAS) 39%Late inbound plane 15%Severe weather 4%

All flights BOS → JAX · Connecting off DL 5597? Check the risk

DL 5597: JAX → BOS

Scheduled to leave Jacksonville at 12:24 p.m. local time, operated by Republic Airways as YX 5597. Over the past year it arrived on time 74% of the time (159 flights), better than other DL flights on the route at that hour (65%). Last seen in the data Aug 30, 2026.

Month by month

40%70%100%Mar 2026: 63% on time (24 flights)63MarApr 2026: 69% on time (26 flights)69AprMay 2026: 90% on time (29 flights)90MayJun 2026: 86% on time (28 flights)86JunJul 2026: 70% on time (27 flights)70JulAug 2026: 60% on time (25 flights)60Aug

By day of week

DayFlightsOn time
Monday2552%
Tuesday2580%
Wednesday2568%
Thursday2576%
Friday2273%
Saturday11—
Sunday2681%

Why it was late

Air traffic & airport (NAS) 42%Airline (crew, maintenance, ops) 37%Late inbound plane 20%

All flights JAX → BOS · Connecting off DL 5597? Check the risk

Questions

How often is DL 5597 from BOS to JAX late?

Delta Air Lines 5597 from Boston, MA to Jacksonville, FL arrived 15 or more minutes late, was diverted or was cancelled on 18% of 175 scheduled flights between September 2025 and August 2026. 0.0% were cancelled.

How often is DL 5597 from JAX to BOS late?

Delta Air Lines 5597 from Jacksonville, FL to Boston, MA arrived 15 or more minutes late, was diverted or was cancelled on 26% of 159 scheduled flights between September 2025 and August 2026. 1.3% 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.