Smaller Planes, More Flights: The Facts Behind Flight Delays

Back in the 1980s, a flight from Phoenix to Chicago meant flying a widebody jet. Today, a passenger on such a route is more likely to be on a 737, an A320 or an MD-80 single-aisle plane than a 767. The ubiquity of the 737 and A320 (the MD-80 is mercifully on its way out), along with the rise of the regional jet, has led to crowded skies, packed taxiways and increasing delays. Affordable airfare spiked the demand. But rather than larger planes to meet it, the industry went toward a glut of smaller aircraft.

“You’re tempted to think … Instead of flying a 200-seat 767 from New York to Los Angeles, make it a 747 instead, with 450 seats,” wrote Patrick Smith, commercial pilot, author of Ask the Pilot and blogger. “But that’s not how it happened.”

Southwest Airlines is one example of the “many small planes” phenomenon. It has nearly 560 aircraft, all narrow-body. It has six daily flights from Phoenix to Los Angeles – some with as little as 40 minutes between them.

Southwest bases its business model on the 737, though it added some 717 jets to its fleet by buying AirTran earlier this year. The airline aims for one aircraft family to standardize maintenance and training requirements – all of which saves money.

“Also, carriers have switched many flights to smaller regional jets, which don’t fly as fast as bigger planes and can also force planes behind them to slow down,” Scott McCartney wrote in The Wall Street Journal.

Regional jets are even smaller than Southwest’s 737s or the A320-series planes low-cost carrier Jet Blue prefers.

McCartney’s sources said planes not only spend longer in the air, but an average of 10 minutes more on the ground than they did in 1977. The conclusion? The taxiways are more crowded.

The crowded skies are also an added burden for air traffic controllers. Smith and many other writers say the nation’s air traffic-control system are already antiquated and insufficient for current needs.

Economics lecturer Lynne Kiesling points out that airlines have no incentive to choose bigger planes – airports charge for landing slots by weight. Instead, the fees should be based on time slot: higher-demand time slot, higher landing fee. That would create incentives to land as many people as possible in that slot.

Kiesling hints at but doesn’t fully explore aircraft separation. Some aircraft generate more wake turbulence, and they need to be separated from other aircraft. The Boeing 757 is notorious for its turbulence, despite being a medium-sized jet. Wide-body jets also generate quite a bit. That means regional jets need to be insulated from them, creating delays as they wait for the larger aircraft to move a safe distance away.

So what’s the solution?

There’s no agreement about that. Too many airlines are too entrenched in using smaller aircraft. Some, like Southwest, depend on it for short-term success. But there has to be a point at which the flying population will grow too large for the system to work. That may be a long time in the future, but it’s something airlines should be considering right now.