Wow! Just look at this "babe"!! Convair B-36: http://en.wikipedia.org/wiki/Convair_B-36 The genesis of the B-36 can be traced to early 1941, prior to the entry of the US into World War II. At the time it appeared that there was a very real chance that Britain could fall, making a strategic bombing effort by the US against Germany impossible. The United States Army Air Corps opened up a design competition for the very long-range bomber on 11 April 1941, asking for a 450 mph top speed, a 275 mph cruising speed, a service ceiling of 45,000 feet, and a maximum range of 12,000 miles at 25,000 feet.These proved too demanding for any short-term design, so on August 19, 1941 they were reduced to a maximum range of 10,000 miles, an effective combat radius of 4,000 miles with a 10,000 pound bombload, a cruising speed between 240 and 300 mph, and a service ceiling of 40,000 feet. B-29 to the left and B-36 to the right!!!!! Looks like a baby´s toy!
They are big but I don't think they would have survived very well against the Mig-15. They tried B-29 strikes in Korea and had alot of losses so a larger target would not do much better at such a low speed. The USAF must have known that too because they tried several types of parasite fighters to be carried in the B-36 bomb bay such as the Goblin and a version of the F-84 but found it too dangerious to recover the aircraft in flight. I think the B-47 put the B-36 out to pasture in about 10 years of less as well as air to air refueling.
The only reason the B-36 saw any operational service post war at all was the USAF's need for a credible intercontinential bomber. In the late 40's and early 50's the B-36 was it. The B-47 didn't have the range or load capacity. The B-52 wasn't on line yet. So, in order to justify their existance as a seperate service the USAF needed the B-36. It certainly was not because the aircraft was really that good. It wasn't. By late 1940's early 50's standards it was a sitting duck to enemy interceptors. It was slow, huge, and horribly unmaneuverable. The USAF tried to help this with more powerful engines and then adding four small turbojets. But, these did little to fix what was an obsolete design before it even flew the first time.
I have seen the XC-99 a number of times in the 70's and 80's. It was parked out in a field between Kelly and Lackland AFB. There used to be a number of surplus types parked there but I don't know what became of them. They were just parked in the field and left. They had a T-38, a C-45, an F-100 and several F-105's and a Huey, all in poor condition but intact. The XC-99 had fire in the cockpit section set by homeless people in the past and had sat there decades.