Record summer airline travel is starting, and so are the flight delays

Summer air travel is expected to soar in the United States. The Transportation Security Administration screened a high of 2.99 million individuals on Sunday, June 23 — exceeding a record set just weeks earlier on May 24 — and the TSA is forecasting a record-setting July 4 holiday period. TSA expects to screen more than 32 million travelers in all between Friday, June 28, and Monday, July 8, a 5.4% year-over-year increase in travel for the holiday.

The record-breaking air traveler numbers come amid airline challenges, from supply chain delays to intense regulation, the Boeing safety crises limiting new planes coming to market, air traffic controller “fatigue,” extreme weather delays, and rising costs which have hit the carriers’ bottom line and compressed margins.

Airports weren’t wholly ready for the initial summer rush. Over 6,000 flights were delayed by the evening of Friday, May 24, on the East Coast alone. While there may be enough flights to meet demand, the record travel still pose challenges to airports, airlines, and travelers. For now, the airlines are expressing confidence.

Delta Air Lines CEO Ed Bastian told CNBC’s “Squawk Box” this week that its performance levels are excelling, with the “best first quarter reliability [Delta has] ever seen.” (Delta has the best on-time record in the U.S.)

But there will also be the need for coordination.

American Airlines CEO Robert Isom told “Squawk Box” the company is making sure to “run the most reliable airline possible,” but factors affecting on-time flights vary from weather to air traffic control issues.

Air traffic, extreme weather

The Federal Aviation Administration has found a shortage of up to 3,000 needed air traffic controllers. Last summer, a record-breaking summer for airports, there were air traffic jams and near collisions amid challenges in flight coordination. Based on air traffic patterns and airport density, New York City and Florida are subject to the highest risk of backups.

The massive heat wave across the U.S. was a peek at the kind of extreme weather that can lead to travel issues. The National Oceanic and Atmospheric Administration expects disruptive weather for the holiday week, with storms across the Midwest and East Coast, and continuing dangerous heat in the Southwest and interior Northeast.

Extreme temperatures cause technical failures that result in delays. High heat creates thin air, which hampers the plane’s thrust for takeoff and ascent. That means airplanes need more runway for takeoff or a lighter aircraft — by removing baggage or passengers. And it means that very high temperatures increase the risk of flight cancellations. The best bet to avoid this risk is to take early morning and late-night flights.

Good news to reduce travel anxiety

If…