The major production version of the Skyknight was the F3D-2. Preliminary specifications for the F3D-2 were released by the Navy on May 23, 1949, and the letter of intent was issued in October of 1949. The F3D-2 had improved cockpit air conditioning, a thicker armored windshield, revised electronic equipment, as well as improved versions of interception, tail warning, and gun targeting radars. In addition, the F3D-2 had a General Electric G-3 autopilot and was provided with wing spoilers for an improved rate of roll. According to original plans, it was to have been powered by two 4600 lb.s.t. Westinghouse J46-WE-3 turbojets housed in enlarged nacelles, which would have offered a substantially enhanced performance.
Unfortunately, the J46 experienced severe developmental difficulties and was still not available when the first F3D-2 was ready for its maiden flight in early 1951, and the first F3D-2 was powered instead by two 3400 lb.s.t. J34-WE-36s. It took off on its maiden flight on February 14, 1951. In the event, the J46 never did overcome its teething troubles and production of this engine was cancelled, forcing all production F3D-2s to settle for the less-powerful J34-WE-36s. However, all F3D-2s retained the larger engine nacelles that had been designed for the J46.
A total of 237 F3D-2s were built, the last example being produced on March 23, 1952.
The following Navy squadrons operated the F3D-2: VC-3, VC-4, VC-33, VX-3, VX-4, VX-5, VFAW-3, VF-11, VF-14, VF-101, VF-121, and VT-86.
The following Marine Corps squadrons operated the F3D-2: VMF(N)-542, VMF(N)-513, VMF(N)-531, VMF(N)-46, VMC-3, VMFT(N)-20, VMCJ-1, VMCJ-2, and VMCJ-3.
VMF(N)-542 deployed to Korea with its F3D-2s in the spring of 1952. They were soon transferred to VMF(N)-513 based at Kunsan (K-8). Their primary mission was to fly night escort missions for Air Force B-29 bombers. On November 2, 1952, pilot Maj William Stratton and radar operator Hans Hoagland shot down a North Korean Yak-15, the first jet-vs-jet night kill. In subsequent night actions, F3D-2s accounted for another Yak-15 and six MiG-15s, with no losses to themselves, which gave the Skyknight an overall 8-0 superiority in Korea. In addition, no Air Force B-29 was ever lost on a F3D-2-escorted mission. VMF(N)-513 crews also flew some night strike and interdiction sorties. Two Skyknights were lost in combat to unknown causes.
Although carrier-capable, most Navy F3D-2s operated from shore bases. The only Navy squadron to deploy the Skyknight at sea was VC-4, which participated in a 1952 cruise aboard the Coral Sea and a 1952/53 cruise aboard the Midway, both cruises being to the Mediterranean. A Skyknight detachment also operated aboard the USS Lake Champlain during the closing months of the Korean War.
The designation F3D-2B was assigned to an F3D-1 experimentally fitted with "special armament" in 1952. The details of these tests are unknown.
Sixteen F3D-2s were modified as missile-armed fighters under the designation F3D-2M. Their guns were removed and an APQ-36 radar was installed in a longer nose cone. Four hardpoints were mounted underneath the wings for Sparrow missiles, two inboard of the wing fold and two outboard.
35 F3D-2s were modified as electronics countermeasures aircraft with their radar installations replaced with specialized ECM equipment. The first such conversion was made in 1955, and the designation F3D-2Q was assigned to these planes.
Five F3D-2s were modified into night fighter trainers as F3D-2T. 55 F3D-2s were converted to F3D-2T2 radar operator trainers.
In September 1962, the F3D-2 was redesignated F-10B under the new Tri-Service unified designation system. The F3D-2M became MF-10B, the F3D-2Q became EF-10B, and the F3D-2T2 became TF-10B.
The performance of the Skyknight was never very impressive, and, following the end of the Korean War, the Skyknights were rapidly replaced in Navy frontline service by more advanced single-seat types such as the F4D Skyray. The Navy Skyknights were then relegated to training and experimental roles. F3D-1Ms and F3D-2Ms were used by VX-4 at the Naval Air Missile Test Center at Point Mugu, California for evaluation of the Raytheon Sparrow semiactive radar-homing air-to-air missile. Skyknights also flew with the Naval Parachute Facility at El Centro, California, with the Naval Air Ordnance Test Station at Chincoteague, Virginia, with the Naval Air Development Unit at Sout Weymouth, Massachusetts, and with the Naval Ordnance Test Station at China Lake, California. China Lake personnel frequently grafted special nose sections to their F3D-2T2s and F2D-2Ms to test new radar installations and electronic equipment. One of these was F-10B 124610, upon which an F-4 Phantom nose was grafted. F3D-2 124619 had a modified nose radome used by Westinghouse to develop the APQ-72 radar for the F4H-1 Phantom. TF-10B 124630 was grafted with a A-4 Skyhawk nose. These tests continued into the early 1980s with three Skyknights (124598, 124630, and 125807) bailed to Raytheon and flown with US Army markings. These were the last flyable Skyknights.
The Skyknight remained active with the Marine Corps for somewhat longer than it did with the Navy. By the time of Vietnam, EF-10Bs electronic countermeasures aircraft were still serving with VMCJ-1, -2, and -3. They flew tactical jamming and ferret missions out of Da Nang with VMCJ-1 in support of strike aircraft attacking targets in North Vietnam. On such missions, the Skyknight would usually fly a straight-line course across the suspected radar station's position, and the electronic signal receiver and analyzer would reveal the approximate location, type, and range of the enemy radar installation. The job of attacking the radar installation would then be assigned to other aircraft called in for the mission, or, alternatively, the station could be jammed by the Skyknight itself by transmitting opposing electronic signals or by dropping chaff. VMCJ-1 flew 791 missions in support of strikes over North Vietnam and Laos. VMCJ-1 was withdrawn from Vietnam in 1969, and the last Marine Corps EF-10Bs were retired in May of 1970.
Few Skyknights survive today. EF-10B BuNo 124618 is at the USMC Museum at Quantico, Virginia. F3D-2T2 BuNo 124626 is at the Pima County Air Museum. XF3D-1 BuNo 121458 is at the Naval Air Museum in Pensacola, Florida. F-10B BuNo 125870 is on display in bogus markings at NAS Los Alamitos.
Engines: Two Westinghouse J34-WE-36 axial-flow turbojets, each rated at 3400 lb.s.t. for takeoff. Performance: Maximum speed 580 mph at sea level, 565 mph at 20,000 feet, 493 mph at 35,000 feet. Cruising speed 402 mph. Landing speed 116 mph. Initial climb rate 3700 feet per minute. Service ceiling 38,200 feet. Absolute ceiling 44,000 feet. Combat range 400 miles. Maximum range 1375 miles. Weights: 18,160 pounds empty, 23,575 pounds loaded, 27,681 pounds maximum. Dimensions: wingspan 50 feet 0 inches, length 45 feet 5 inches, height 16 feet 1 inches, wing area 400 square feet. Fuel: Maximum internal fuel of 1350 US gallons. Two 150 US gallon drop tanks could be carried on underwing pylons, bringing total fuel capacity to 1650 US gallons. Armament: Four 20-mm cannon with 800 rounds. Two underwing pylons just inboard of the wing folding point which could carry up to 4000 pounds of bombs, rockets, or fuel tanks.