The B-36F differed from the B-36D primarily in having more-powerful 3800 hp Pratt & Whitney R-4360-53 engines. Each of these engines generated 3800 hp--300 hp more than the engines of the B-36D. The B-36F also had improved radar and electronics countermeasures equipment. The K-3A radar system and the APG-32 gun laying radar were standard. A chaff dispenser was installed to confuse enemy radar. Top speed increased to 417 mph and service ceiling to 44,000 feet with a standard combat load and 264,300 combat weight.
The first B-36F (49-2669) took off on its maiden flight on November 18, 1950. The first B-36F was accepted in March of 1951. However, the first B-36Fs did not reach SAC until August of that year.
At first, the R-4360-53 engines of the B-36F were not entirely satisfactory because of excessive torque pressure as well as ground air cooling and combustion problems. However, these problems were resolved fairly quickly.
The last of 34 B-36Fs was manufactured in October of 1952, but the Air Force did not get its last B-36F until several months later.
A number of the new B-36Fs were modified as featherweight aircraft during 1954.
The Air Force ordered 24 long-range reconnaissance versions of the B-36F designated RB-36F. The first four RB-36Fs were accepted in May of 1951. The remaining were accepted between August and December of 1951.
Like most of the other B-36 series aircraft, some B-36Fs were modified to Featherweight II or III requirements. The Featherweight III program eliminated all the defensive armament except the two 20-mm cannon in the tail, along with most of the defensive fire control avionics.
One B-36F (serial number 49-2677) was modified for use as a carrier for the XB-58 test program. The main fuselage and wing structure of the B-58 was carried in the bomb bay.
The RB-36F was a reconaissance version of the B-36F. It was similar to the RB-36D, but differences included the same engine upgrade as the B-36F plus an improved defensive fire control system. During the latter part of the RB-36F's service life, as newer reconnaissance aircraft became available, the reconnassaince role role of the RB-36F became secondary, and the planes were modified to give them an increased offensive combat role. The reconnaissance cameras were retained in bomb bay 1, but the bays 2 through 4 were stripped of all reconnaissance equipment and returned to actual bomb bays. The ECM equipment housed in bomb bay number 4 was moved further aft. Initially the RB-36F was equipped with the full set of 16 20-mm cannon, but some were converted to Featherweight III configuration under which all but the tail cannon were removed.
One B-36F was modified to test the Fighter Conveyor (FICON) concept. It was redesignated GRB-36F
49-2669/2675 Convair B-36F-1-CF Peacemaker 49-2677 Convair B-36F-1-CF Peacemaker 49-2678/2683 Convair B-36F-5-CF Peacemaker 49-2685 Convair B-36F-5-CF Peacemaker 49-2703/2711 Convair RB-36F-1-CF Peacemaker 2707 used in FICON and TOM-TOM project tests. Redesignated JRB-36F after 1955. 49-2712/2721 Convair RB-36F-5-CF Peacemaker 50-1064/1073 Convair B-36F-10-CF Peacemaker 50-1074/1082 Convair B-36F-15-CF Peacemaker 50-1098/1099 Convair RB-36F-10-CF Peacemaker 50-1100/1102 Convair RB-36F-15-CF Peacemaker
Engines: Six 3800 Pratt & Whitney R-4360-53 Wasp Major air cooled radial engines, plus four 5200 lb.s.t. General Electric J47-GE-19 turbojets. Performance: Maximum speed 417 mph at 37,100 feet, 414 mph at 40,200 feet. Cruising speed 235 mph. Stalling speed 123 mph. Initial climb rate 2060 feet per minute. Service ceiling 44,000 feet. Combat ceiling 40,900 feet. Combat radius 3200 miles with 10,000 pounds of bombs. 7743 miles ferry range with 30,630 gallons of fuel. Weights: 167,647 pounds empty, 264,300 pounds combat, 370,000 pounds maximum. Dimensions: Wingspan 230 feet 0 inches, length 162 feet 1 inches, Height 46 feet 8 inches, wing area 4772 square feet. Armament: Two 20-mm M24A1 cannon each in six retractable, remotely-controlled fuselage turrets, tail turret and nose mounting, with 9200 rounds of ammunition. Normal bomb load up to 72,000 pounds. Maximum bomb load 86,000 pounds