> I was surprised that SQ was the only third party airline to have its livery on Concorde, as I saw plenty of pictures of Concordes with Braniff livery on on side.
"Domestic flights between Dallas-Fort Worth and Washington Dulles airports were operated by Braniff with its own cockpit and cabin crews. During the domestic flights, the Braniff's registration numbers were affixed to the fuselage with temporary adhesive vinyl stickers. At Washington Dulles, the cockpit and cabin crews were replaced by ones from Air France and British Airways for the continued flight to Europe, and the temporary Braniff registration stickers were removed. This process was reversed after alighting in Washington Dulles from Europe for the domestic flights to Dallas-Fort Worth."
> Domestic flights between Dallas-Fort Worth and Washington Dulles airports were operated by Braniff with its own cockpit and cabin crews
Presumably own cockpit crew, but I had an instant vision of a replaceable cockpit module that was swapped out at Dulles.
Operating as an American owned airline between Dallas and Washington allowed them to take Dallas-Washington passengers, rather than only Dallas-Europe passengers. This was essential for the economics of the flight to work. At the time BA and AF had 3rd and 4th freedoms, and possibly 5th, but were not allowed to fly passengers on solely domestic itineraries -- a process called "Cabotage".
"Domestic flights between Dallas-Fort Worth and Washington Dulles airports were operated by Braniff with its own cockpit and cabin crews. During the domestic flights, the Braniff's registration numbers were affixed to the fuselage with temporary adhesive vinyl stickers. At Washington Dulles, the cockpit and cabin crews were replaced by ones from Air France and British Airways for the continued flight to Europe, and the temporary Braniff registration stickers were removed. This process was reversed after alighting in Washington Dulles from Europe for the domestic flights to Dallas-Fort Worth."