likely on the longest runway to give the pilot the most amount of time to bleed off the speed and touch this thing down as softly as you can. whether it's a nose wheel or side wheel, the object, the objective, is to touch it down so it doesn't below more tires. they'll come in, you'll see them make their way down the runway and ever so slightly touch down the rear wheels and try as long as they can to keep that nose up until they bleed off enough airspeed that the nose comes down and touches down as light as they can to keep it in the middle of the runway, so if, for some reason, the plane hits and veers, the pilot has room to work. that's another reason they burn off the fuel, so if something happens, there's no chance of an explosion. it was going to portland, oregon, so there was all of the fuel and burnoff time to be had, which is what going on.