Martin JRM Mars
A four-engine seaplane, the Martin JRM Mars was popularized during the Second World War and was the largest seaplane used by the Americans as well as other Allied forces in the War. In spite of how impressive and effective these planes were, only seven of them was ever built. After the war, four of the flying boats left transitioned into civilian use and became fire fighting water bombers, making them even more useful. However, those models have been retired.
Boeing KC-135 Stratotanker
While refueling strategic bombers may not be easy, that’s exactly what the task of the KC-135 Stratotanker is. During the Vietnam War, this aircraft was used a lot for the Americans and became a very big strategic benefit in Operation Desert Storm. Interestingly, both the Boeing 707 and the KC-135 was derived from the Boeing 367-80. The 136-feet Boeing KC-135 became revolutionary in a way that it was the very first jet-powered refueling tanker of the United States Air Force.