The Data-Driven Recommendations to Avoid Flight Delays ✈️

The Data-Driven Recommendations to Avoid Flight Delays ✈️

✈️ Dataset Overview

The flight data represents 328521 domestic flights that occurred in 2023. Each flight corresponds to one row.

All records in the dataset indicate departures from three New York airports:

• John F. Kennedy International Airport (JFK) - 109416 flights;
• Newark Liberty International Airport (EWR) - 117596 flights;
• LaGuardia Airport (LGA) - 101509 flights.

On average, the least busy day of the week is Thursday (38030 flights), and the busiest is Saturday (49445 flights took off). The difference is more noticeable in EWR and LGA than in JFK, where the number of flights over the week doesn't change much.

August was the busiest month of the year (28841 flights), and February was the least busy (23690 flights).

LGA and EWR operate for shorter destinations, whereas JFK has more flights to the West Coast, Alaska, and Hawaii. The average flight distance in miles from those airports is:

• JFK: 1275 miles per flight;
• EWR: 1065 miles per flight;
• LGA: 785 miles per flight.

The total air time reaches a staggering 94 years and 24 days, and the total distance travelled equals 344.5 million miles (3.7 distance from Earth to the Sun)!

The top 5 popular carriers in all three airports are:

• United Airlines Inc. - 57979 flights (17.65%);
• JetBlue Airways - 54169 flights (16.49%);
• ExpressJet Airlines Inc. - 51356 flights (15.63%);
• Delta Air Lines Inc. - 47761 flights (14.54%);
• Envoy Air - 25163 flights (7.66%).

⚠️⏱️ Delays Insights

Rank of carriers by their delay frequency

Numerous factors contribute to departure delay, such as weather, air traffic congestion, technical issues, safety procedures, delay of an aircraft from its previous flight, waiting for passengers from a delayed connecting flight, etc.
I considered over 15 minutes as the amount of time that can cause inconvenience, and over 1 hour being a source of potential disruption and customer frustration.

But data shows that some carriers are doing better than others in on-time performance:

ExpressJet Airlines Inc. has almost a third of all flights delayed, more than any other carrier. Mesa Airlines Inc. has about one in seven flights that are delayed more than one hour.
The best carrier in terms of on-time performance is Hawaiian Airlines Inc., with only 7% of flights delayed over 15 minutes.

Trends in flight delays over a day

There is a common pattern for departure delays for most of carriers (especially big ones): the percentage of delayed departures is the highest after midnight (a handful of flights that were supposed to take off before midnight on the previous day), the lowest value is in the early morning (5-6 am), and gradually increases throughout a day. The rate the percentage of delayed departures increases is steeper in the late evening (8-11 pm).

For arrival delays, there are two peaks of delay frequency: at 1-2 am and at 5 am. The lowest is at 6 am, and gradually increases until the end of the day, too.

There might be many potential reasons why we are unlikely to experience a delay in the early morning:

• No delayed aircraft from previous flights yet;
• Low air traffic, passenger traffic;
• Weather is usually calm in the morning and tends to worsen in the afternoon (e.g., thunderstorms);
• Security concerns and operational challenges like fueling delays are more likely to happen in the afternoon; etc.

Delay trends over a week

As revealed earlier in the report, Thursdays are usually less busy than other days. The chart below confirms that the greater number of flights an airport operates might lead to more delays.

Interestingly, Tuesdays have the highest % of flights delayed both over 15 minutes and over 1 hour.

Trends of delays over the year

In general, in June through July and December, we are more likely to experience a delay than in the rest of the year. Summertime is when people go on vacation, and before Christmas tend to travel more as well. Fall can be considered a quiet period and the best time to avoid flight delays.

Delays by departure airport

All three departure airports have a similar number of flights, yet data suggests they handle delays differently.

EWR airport in Newark, NJ, is doing poorly compared to the other two. Even considering all flights that started in EWR, the average delay is over 15 minutes. LaGuardia Airport is working more like a clockwork.

Arrival delays by destination

By trying to investigate which routes are prone to disruptions more than others, I focused on the top 10 popular travel destinations from NYC airports.

Fort Lauderdale–Hollywood International Airport (FLL) in Florida and Hartsfield–Jackson Atlanta International Airport (ATL) in Georgia both have over 25% of flights arrive more than 15 minutes late. On the contrary, Miami International Airport (MIA) has only 18.5% of flights delayed for a given amount of time.

Flight delays vs distance

While it's plausible that some flights can catch up with a delay on longer distances, the scatter plot below shows the relationship between flights arriving with more than 1 hour delay and the distance travelled:

Indeed, almost all flights over 2000 miles were significantly late (> 1 hour) in just 10% or less of cases. Also, notice that flights with the most notorious delays departed from Newark (EWR).

📋💡 Summary

• ExpressJet Airlines, Mesa Airlines, and Frontier Airlines have more frequent delays.
• Hawaiian Airlines, US Airways, and Alaska Airlines are the best in terms of on-time performance.
• 5-6 am is the least likely time to experience a delay, midnight to 2 am is the most likely.
• The biggest delays usually happen on Tuesdays, the smallest occur on Thursdays.
• Throughout the year, summer months and December experience the most delays, and fall months have the least.
• Newark airport (EWR) is more susceptible to disruptions than JFK or LaGuardia.
• Within the top 10 popular destinations from NYC airports, FLL and ATL airports in the US Southeast tend to have the highest delays upon arrival. Airports in Miami (MIA) and Boston (BOS) have the smallest chance of receiving a delayed flight.
• A longer flight distance is associated with a lower chance of arrival delay.

👌 Recommendations

• Opt for flights in the early morning, as delays tend to accumulate later in the day.
• Avoid EWR airport if possible, the less busy LGA being a good alternative.
• Choose airlines with high on-time performance ratings, like Hawaiian Airlines, US Airways, or Alaska Airlines.
• Consider travelling by plane on Thursday during the fall when the fewest delays occur.
• Be aware that popular vacation destinations like Florida may contribute to longer and more frequent delays.