North American YB-107A
I usually have a dozen or more windows open at any one time. As as your topic had been open for some twenty minutes or so, I was surprised to see that the first picture of the Constellation had loaded. That made me realise that you had in fact got the image source address's correct, but that angelfire's website was the problem. By right-clicking on the other two angelfire logos and going down to 'properties', I was able to get the other two photos URL addresses. These I loaded into two new browser windows and let them take their time to load.
The North American YF-107A really had me stumped. I didn't think there was nearly enough detail in that photo to enable me to identify it. It was only that window to the rear of the cockpit canopy that could identify the aircraft.
YB-107A photo: Hy Yarchun
Of course the "object" above the aircraft had me confused as well. Quite by chance I came across a photo showing an aircraft with this unusual dorsal air- intake and when I did a double-take on the pic I recognised the trapezium-styled rear cockpit window and that's how I identified it.
The Connie has a very unique front undercarriage and that pretty much gave that one away.
The Valkyrie had its six engine nozzels all grouped together in the middle at the rear and while I thought I had that one in the bag, I had to check in order to make sure and the tail number matched with my pics.