Long Island MacArthur in September 2023

76.0%departed on time

BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report.

In September 2023, reporting carriers scheduled 333 domestic departures from Long Island MacArthur (ISP). 76.0% left less than 15 minutes late and 73.6% reached their destination on time; 0.9% were cancelled.

Nationally that month, 80.5% of flights departed on time and 80.1% arrived on time, so ISP departures were 4.5 points below the national departure figure.

Flights arriving at ISP that month were on time 75.7% of the time (333 scheduled arrivals).

Of the delay minutes that carriers assigned to a BTS cause category that month, national aviation system 38%, air carrier 29% and late-arriving aircraft 28%.

On time 73.6%
Arrived 15+ minutes late 24.9%
Cancelled 0.9%
Diverted 0.6%

Every scheduled departure from ISP in September 2023, judged by arrival at the destination.

September 2023 against a year earlier, the airport's year and the nation

Measure	Sep 2023	Year earlier	ISP, 12 months to Jul 2026	All reported flights, Sep 2023
Departed on time	76.0%	—	73.7%	80.5%
Arrived on time	73.6%	—	73.6%	80.1%
Cancelled	0.9%	—	2.1%	1.2%
Average departure delay (late minutes only)	20.6 min	—	18.8 min	14.1 min
Scheduled departures a day	11	—	14	18,978
Scheduled departures	333	—	4,966	569,338

Airlines that month

Reporting carrier	Flights	Share	On time	Avg arrival delay	Cancelled
WN Southwest Airlines	186	56%	76.3%	9.5 min	1.1%
F9 Frontier Airlines	147	44%	70.1%	18.5 min	0.7%

Busiest routes that month

Route	Cities	Flights	On time	Avg arrival delay	Cancelled
ISP–BWI	Islip to Baltimore	112	90.2%	1.3 min	1.8%
ISP–MCO	Islip to Orlando	106	69.8%	11.4 min	0.9%
ISP–TPA	Islip to Tampa	53	71.7%	28.5 min	0.0%
ISP–PBI	Islip to West Palm Beach/Palm Beach	35	40.0%	34.2 min	0.0%
ISP–MYR	Islip to Myrtle Beach	10	50.0%	40.4 min	0.0%
ISP–RDU	Islip to Raleigh/Durham	9	66.7%	10.3 min	0.0%
ISP–FLL	Islip to Fort Lauderdale	5	100.0%	-24.6 min	0.0%
ISP–BNA	Islip to Nashville	3	66.7%	5.3 min	0.0%

By scheduled departure hour

100

On-time share:under 62%6270768288% and over

Share of departures that left less than 15 minutes late, by scheduled hour (local time), September 2023.

Delay causes

BTS cause category	Share of delay minutes	National, Sep 2023	Minutes
Air carrier	29.2%	36.4%	2,002
Late-arriving aircraft	28.3%	38.3%	1,938
National Aviation System	37.5%	19.9%	2,566
Extreme weather	5.0%	5.1%	340
Security	0.0%	0.2%	0

6,846 delay minutes on 83 flights that arrived 15 or more minutes late and carried a cause report. Carriers assign the categories; see what each category means.

Questions and answers

How many flights left ISP on time in September 2023?

76.0% of 333 scheduled domestic departures left less than 15 minutes late, and 73.6% reached their destination on time. The national figures that month were 80.5% and 80.1%.

How does that compare with a year earlier?

September 2022 is outside the 36 months on file, or the airport had too few reported flights that month.

Provenance

Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, file for September 2023; public domain. Domestic scheduled flights by reporting carriers, totals and averages only. The site's data runs through July 2026. Full record for ISP · methodology · corrections.