Slide onto a United Airlines flight today in say, Tulsa, and you could fly up to United’s O’Hare hub, kill an hour or so, then transfer onto another United flight through to London. One airline, one fare, one ticket, timed transfers, two flights, too easy. But before aviation was deregulated in the United States, that simple itinerary wasn’t so simple.
A regulated market that squashed free enterprise
Before deregulation in 1978, the now-defunct Civil Aeronautics Board (CAB) ruled over commercial airline operations in the United States with an iron fist. The CAB “managed” which airline would fly on what route, set minimum limits on passenger fares, and did an excellent job of suppressing competition.
If an airline thought a market was underserved or a new route had potential, the CAB’s red tape and bureaucratic inertia would almost certainly kill the idea off before it took flight.
That highly regulated and anti-competitive environment threw up quite a few interesting workarounds. One was the idea of interchange flights. They ended when the aviation market was deregulated. But for several decades, between the 1950s and 1980s, US airlines of the time embraced the concept.
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To go back to the hypothetical Tulsa to London example. Before regulation, a single airline would not have been allowed to operate that route. There’s was no handy through ticket or seamless bag transfers on United Airlines. So how would United get around this?
They’d do deal with another airline. It’s 1969, who would United call? Maybe North Central Airlines. United would put a plane onto the O’Hare – Tulsa sector, but North Central employees would crew it. Passengers boarding in Tulsa would land in Chicago. The aircraft would be fueled, serviced, and a United crew would take over and operate the sector through to London. The passengers could go through.
One particular agreement even allowed Braniff to claim they were operating Concorde services out of Dallas Fort Worth via Washington DC.
A precursor to modern codeshares and alliances
Interchange flights are a kind of precursor to modern codeshares and alliances. They came about because the CAB wouldn’t allow airlines to operate through flights or destinations they wanted to serve. Interchange flights sound unwieldy and inefficient, but many US airlines got them down to a fine art.
Sometimes, the plane dedicated to a specific interchange flight would feature livery and logos from both airlines. If a foreign aircraft were flying a US domestic sector under an interchange flight agreement, registrations and ownership would temporarily change at the entry airport. Decals would be slapped on planes and paperwork signed in cockpits.
It involved now-defunct carriers like Braniff, Continental, Eastern, and Pan Am. Also, contemporary airlines such as American and Delta co-operated in ways that would seem laughable now.
Pan Am’s interchange flights to Europe
Pan Am was a significant player in the interchange flight game. Going across to Europe, they co-operated with Braniff on the Houston-Dallas-Chicago-London-Frankfurt run using a 707. They had an agreement with Delta to operate a DC-8 on the New Orleans-Atlanta-Washington-London-Frankfurt run. There was also an interchange flight with Northwest Orient flying Minneapolis/St. Paul-Detroit-London.
Towards the end of the interchange flight era, Delta Air Lines was laying on one of its Boeing 747-132s on that milk run between New Orleans and Frankfurt. Of course, you have to keep in mind that the aircraft of that era did not have the range that modern aircraft have. These milk run flights were common across many airlines and were not restricted to interchange type flights.
Pan Am’s deal with Northwest Orient built on existing regulated Northwest flights between Minneapolis/St. Paul and Detroit. By teaming up with Pan Am, that aircraft continued onto London using a Pan Am crew. That’s the critical point of difference to modern agreements. Airlines used each other’s planes.
Interchange flights also allowed airlines to claim a presence in markets the CAB wouldn’t let them serve on their own.
Braniff flies the Concorde
It wasn’t just a practice exclusive to US airlines. In the late 70s, towards the end of the interchange flight era, Braniff did a deal with British Airways. In a grand folly we don’t see enough of these days, British Airways laid on a Concorde in an interchange flight agreement with Braniff. The flight flew London-Washington Dulles-Dallas Fort Worth. Braniff’s crew operated the domestic leg.
The flight operated five days a week with a one-way fare costing US$987. A New York Times journalist at the time said of the flight;
“What followed the coffee was a breakfast of fresh papaya, guava, pineapple, strawberries and mangoes, croissants and brioche that might have come from a Paris bakery, a pretty good approximation of eggs benedict and a soufflé Gruyère, all washed down with Piper‐Heidsieck Cuvée Diplomatique. The china, of course, was Limoges.”
The flights didn’t last long, undoubtedly losing a colossal amount of money along the way and probably aiding and abetting Braniff’s collapse in 1982. Still, it did allow Braniff to claim they operated Concorde flights. But towards the end, the loads on these Concorde flights were running at just 20%.
Like Pan Am, Braniff dabbled widely in interchange flights. The Texas-based airline was allowed to fly into Central America and the Caribbean and operated several interchange flights further down into South America. Alas, those flights probably didn’t have the same standard of catering as those Concorde flights.
The demise of interchange flights
Deregulation put an end to interchange flights. Soon after, the Civil Aeronautics Board was closed down. Suddenly there was nothing to stop United operating through to Tulsa from London if they wished to do so. Then other things happened. New aircraft entered service with superior ranges. Those milk runs bit the dust. Suddenly, subject to air services agreements and slots, United could operate directly from Tulsa to London if they so wished.
At much the same time, airlines got wise to the hub and spoke model. They learned how to handle transits and transfers. Deregulation helped fuel this. The domestic market opened up wide to US carriers. Suddenly airlines could have a dozen incoming domestic flights from various US airports, and they could connect with outgoing flights elsewhere. Individual airlines could bring everything came in-house,
The last known interchange flight survived into the early 1990s. American Airlines inherited an interchange flight with Alaska Airlines. Flights from Dallas, Houston, and Denver interchanged with Alaska Airlines at Seattle.
Now, interchange flights are a quirk of aviation history. The closest we have are codeshares and alliances. The efficiencies of modern codeshares and alliances owe something to the lessons learned from interchange flights. While many of the airlines involved are long gone, others remain. Delta still enjoys doing deals with other airlines. But you’d be hard-pressed to find a LATAM pilot operating a Delta plane these days.