Scott wrote:The B-36 is an impressive looking aircraft.
What's even more impressive is what it took to keep them in the air.
For example, it had four separate, redundant, electrical systems to control the engines. It was discovered, when it entered squadron service, that if all of the electrical systems failed the piston engines could not be shut down after a flight. Someone had to crawl out in the wing and shut them down. A quick examination of the aircraft in service revealed that most of them were flying with two electrical systems inoperative, and some with three. This resulted in an immediate rewriting of the maintenance procedures to make sure that aircraft took off with all the electrical systems operational.
Since the aircraft made routine 24 hour flights changing the spark plugs for 100 hour inspections meant after every fourth flight. The aircraft was capable of 48 hour flights which meant changing the plugs after every second flight. The mechanics had to change 336 spark plugs on each aircraft! (Not counting the 32 igniters in the jet engines.) Unfortunately, these engines were carburetted, not fuel injected, and were prone to icing and in-flight fires.
Most histories of the B-36 say that it was obsolete when it was introduced since jet fighters like the MIG 15 could attack it with impunity. Actually, until aircraft of F-100 class performance entered service the B-36 was a nearly impossible interception task for a fighter above 45,000 feet. The reason, wing area. I have spoken to pilots who actually flew them and what would happen was this. When a fighter was sighted they would get the jet engines lit, increase speed to about 400 mph and turn to force the fighter into a tail chase. At that altitude an F-86 or a MIG was only about 60 to 100 mph faster. When the fighter was almost to gun range the B-36 pilot would reef it into a 3G turn. The fighter pilot would try to pull lead on the bomber by turning in tighter and would be surprised by his high-speed stall. When the fighter stalled, the bomber pilot would resume his original course. The fighter would spin to about 25,000 feet before the air was dense enough for the pilot to recover. At that point he no longer had enough fuel to climb back up to the B-36's altitude and chase it down. The British Canbarra bomber pilots used the same evasive tactics with good effect. Of course all this high altitude high-jinks stopped in the mid 1950s when supersonic fighters entered squadron service and surface to air missiles started to become effective.
As soon as B-52s became available the B-36s were phased out. Not only did the B-52 have better performance than the B-36, but without the piston engines, it was much more reliable (It's still in service!) and much cheaper to fly per mission.