The B-36 took shape as an aircraft of immense proportions.
It was two-thirds longer than the previous "superbomber", the B-29.
The wingspan and tail height of the B-36 exceeded those of the 1960s Soviet Union's Antonov An-22 Antheus military transport, the largest ever propeller-driven aircraft put into production.
Only with the advent of the Boeing 747 and the Lockheed C-5 Galaxy, both designed two decades later, did American aircraft capable of lifting a heavier payload become commonplace.

The wings of the B-36 were large even when compared with present-day aircraft, exceeding, for example, those of the C-5 Galaxy, and enabled the B-36 to carry enough fuel to fly the intended long missions without refueling.
The maximum thickness of the wing, measured perpendicular to the chord, was 7.5 feet (2.3 m), containing a crawlspace that allowed access to the engines.
The wing area permitted cruising altitudes well above the operating ceiling of any 1940s-era operational piston and jet-turbine fighters.
Most versions of the B-36 could cruise at over 40,000 feet (12,000 m).
B-36 mission logs commonly recorded mock attacks against U.S. cities while flying at 49,000 feet (15,000 m).
In 1954, the turrets and other nonessential equipment were removed (not entirely unlike the earlier Silverplate program for the atomic bomb-carrying "specialist" B-29s) that resulted in a "featherweight" configuration believed to have resulted in a top speed of 423 miles per hour (681 km/h), and cruise at 50,000 feet (15,000 m) and dash at over 55,000 feet (17,000 m), perhaps even higher.

The large wing area and the option of starting the four jet engines supplementing the piston engines in later versions gave the B-36 a wide margin between stall speed (VS) and maximum speed (Vₘₐₓ) at these altitudes.
This made the B-36 more maneuverable at high altitude than the USAF jet interceptors of the day, which either could not fly above 40,000 ft (12,000 m), or if they did, were likely to stall out when trying to maneuver or fire their guns.
However, the U.S. Navy argued that their McDonnell F2H Banshee fighter could intercept the B-36, thanks to its ability to operate at more than 50,000 feet (15,000 m).
The USAF declined the invitation from the U.S. Navy for a fly-off between the Banshee and the B-36.
Later, the new Secretary of Defense, Louis A. Johnson, who considered the U.S. Navy and naval aviation essentially obsolete in favor of the USAF and SAC, forbade putting the Navy's claim to the test.

The propulsion system of the B-36 was unique, with six 28-cylinder Pratt & Whitney R-4360 'Wasp Major' radial engines mounted in an unusual pusher configuration, rather than the conventional four-engine, tractor propeller layout of other heavy bombers.
The prototype R-4360s delivered a total of 18,000 hp (13,000 kW).
While early B-36s required long takeoff runs, this situation was improved with later versions, delivering a significantly increased power output of 22,800 hp (17,000 kW) total.
Each engine drove a three-bladed propeller, 19 feet (5.8 m) in diameter, mounted in the pusher configuration, thought to be the second-largest diameter propeller design ever used to power a piston-engined aircraft (after that of the Linke-Hofmann R.II).
This unusual configuration prevented propeller turbulence from interfering with airflow over the wing, but could also lead to engine overheating due to insufficient airflow around the engines, resulting in inflight engine fires.

The large, slow-turning propellers interacted with the high-pressure airflow behind the wings to produce an easily recognizable very-low-frequency pulse at ground level that betrayed approaching flights.
The B-36 took shape as an aircraft of immense proportions. It was two-thirds longer than the previous "superbomber", the B-29. The wingspan and tail height of the B-36 exceeded those of the 1960s Soviet Union's Antonov An-22 Antheus military transport, the largest ever propeller-driven aircraft put into production. Only with the advent of the Boeing 747 and the Lockheed C-5 Galaxy, both designed two decades later, did American aircraft capable of lifting a heavier payload become commonplace.
The wings of the B-36 were large even when compared with present-day aircraft, exceeding, for example, those of the C-5 Galaxy, and enabled the B-36 to carry enough fuel to fly the intended long missions without refueling. The maximum thickness of the wing, measured perpendicular to the chord, was 7.5 feet (2.3 m), containing a crawlspace that allowed access to the engines. The wing area permitted cruising altitudes well above the operating ceiling of any 1940s-era operational piston and jet-turbine fighters. Most versions of the B-36 could cruise at over 40,000 feet (12,000 m). B-36 mission logs commonly recorded mock attacks against U.S. cities while flying at 49,000 feet (15,000 m). In 1954, the turrets and other nonessential equipment were removed (not entirely unlike the earlier Silverplate program for the atomic bomb-carrying "specialist" B-29s) that resulted in a "featherweight" configuration believed to have resulted in a top speed of 423 miles per hour (681 km/h), and cruise at 50,000 feet (15,000 m) and dash at over 55,000 feet (17,000 m), perhaps even higher.
The large wing area and the option of starting the four jet engines supplementing the piston engines in later versions gave the B-36 a wide margin between stall speed (VS) and maximum speed (Vₘₐₓ) at these altitudes. This made the B-36 more maneuverable at high altitude than the USAF jet interceptors of the day, which either could not fly above 40,000 ft (12,000 m), or if they did, were likely to stall out when trying to maneuver or fire their guns. However, the U.S. Navy argued that their McDonnell F2H Banshee fighter could intercept the B-36, thanks to its ability to operate at more than 50,000 feet (15,000 m). The USAF declined the invitation from the U.S. Navy for a fly-off between the Banshee and the B-36. Later, the new Secretary of Defense, Louis A. Johnson, who considered the U.S. Navy and naval aviation essentially obsolete in favor of the USAF and SAC, forbade putting the Navy's claim to the test.
The propulsion system of the B-36 was unique, with six 28-cylinder Pratt & Whitney R-4360 'Wasp Major' radial engines mounted in an unusual pusher configuration, rather than the conventional four-engine, tractor propeller layout of other heavy bombers. The prototype R-4360s delivered a total of 18,000 hp (13,000 kW). While early B-36s required long takeoff runs, this situation was improved with later versions, delivering a significantly increased power output of 22,800 hp (17,000 kW) total. Each engine drove a three-bladed propeller, 19 feet (5.8 m) in diameter, mounted in the pusher configuration, thought to be the second-largest diameter propeller design ever used to power a piston-engined aircraft (after that of the Linke-Hofmann R.II). This unusual configuration prevented propeller turbulence from interfering with airflow over the wing, but could also lead to engine overheating due to insufficient airflow around the engines, resulting in inflight engine fires.
The large, slow-turning propellers interacted with the high-pressure airflow behind the wings to produce an easily recognizable very-low-frequency pulse at ground level that betrayed approaching flights.
Convair B-36 Peacemaker