The 10-engine plane time forgot: Convair's B-36 Peacemaker
The B-36 Peacemaker had six piston engines, four jet engines, and the longest wingspan of any combat aircraft. It was only in service for 11 years. Here's a closer look at this nearly forgotten Cold War deterrent.
The Convair B-36 Peacemaker is the largest piston-powered combat aircraft ever built. Powered by six radial and four jet engines, it bridged the gap between WWII propeller aircraft and the jets of the Cold War. Here's a look at this unique machine.
Designed during World War II, only one prototype was built, the XB-36 seen here. It first flew in August 1946. While there were numerous differences between this and the first production aircraft, the most noticeable is the more traditional cockpit design.
The B-36 has the largest wingspan of any combat aircraft, at 230 feet or 70.1 meters. For scale, that's a B-29 on the left, which was one of the largest aircraft of World War II and first flew only four years before the B-36.
Multiple modifications, including the aforementioned addition of four J47 turbojets, gave the B-36D and later versions the performance intended by the initial design. But by the time they flew, WWII was long over and the need to fly from the east coast of Canada to Berlin and back was no longer the main goal.
Compared to its predecessor, the B-29, the B-36 has slightly faster cruising speed, had a much higher top speed and service ceiling, and could carry a significantly greater bomb load over a longer distance. It was, to put it mildly, a huge leap in performance.
Being one of the largest aircraft to ever fly, and having such impressive lifting abilities for its day, the B-36 became a sturdy platform for a wide range of testing. This is the original prototype, outfitted later to test tracked landing gear.
The B-36 covers one of my favorite eras in aviation, the post-WWII/early Jet Age, where engineers experimented with all sorts of wacky ideas. For instance, this is the NB-36H. It carried, I'm not kidding, an active nuclear reactor.
The reactor never powered the aircraft, though it was running during several dozen flights to test radiation exposure for the crew (how would you like that job?), and overall feasibility of using a reactor to power an aircraft. With the advent of ICBMs, the need for permanently aloft aircraft abated.
Next station rearward was the flight engineer, who had the same number of controls as a standard B-36, with dials and levers for all 10 (10!) engines. We'll see what a standard B-36 cockpit controls look like a bit later.
Convair considered making an airliner version of the XC-99, but the radial engines were too expensive for profitable commercial service. The XC-99 remained in Air Force use until 1959. It's currently in storage at the AMARG Boneyard awaiting restoration.
Initially the idea was for the smaller, faster jet to carry a small tactical nuke while the longer-range but slower bomber loitered outside enemy defenses. Later this was changed to a reconnaissance role, using the RF-84F Thunderflash.
The Jet Age was already ramping up when the B-36 entered service. Its four turbojets were a harbinger of things to come. Convair certainly knew this, and built the all-jet powered YB-60, which was essentially a heavily modified B-36.
The YB-60, seen here with a B-36, had many issues and only the prototype was built. Instead, the Air Force chose a similar design from Boeing that first flew three days before the YB-60: the B-52.
B-52s are still in active service with the Air Force 68 years after the design first flew. They're expected to remain in service until the 2050s, some 90 years after the last aircraft rolled off the assembly line.
Production on the B-36 ended in 1954 with this, serial number 52-2827 The City of Fort Worth. It now lives a quiet, sun-drenched life in the Arizona desert, at the incredible Pima Air and Space Museum.
"The City of Fort Worth" was stationed in El Paso, Texas until 1959, when it and its sisters were retired and replaced by B-52s. Nearly all of the 384 B-36s were scrapped. Only four intact airframes remain.
The massive 28-cylinder, 71.5-liter engines developed 3,800 horsepower. Maintenance was time consuming, as you'd expect with a total of 336 spark plugs across six engines. The props are larger than the propellers on the RMS Queen Mary cruse ship.
The radio operator's station, which is aft of the navigators station and below the pilot and engineer. To the lower right, just beyond the edge of the image, is the entrance to the "communication tube" that allowed access to the rear of the aircraft.
The B-36 is a fascinating look at a peculiar time in aviation. Its size and rapid obsolescence means only a handful remain, but it seems that almost all of those are well taken care of in some excellent aviation museums.