The F-86H was fitted with General Electric J73 turbojet (substantially more powerful than the F-86F's J47-GE-27 engine), deeper fuselage, larger intake duct, greater fuel capacity, larger tail-plane without dihedral, electrically-operated flaps, hydraulically-operated speed brakes and controls, heavier landing gear, improved suspension and release mechanism for carrying droppable wing tanks in conjunction with bombs and rockets. Clamshell-type canopy (similar to that of the F-86D), superior armament (four 20-mm. M-39 cannons, beginning with the 116th production) and improved ejection seat.
The Air Force ordered the F-86H fighter-bomber at about the same time the F-86F entered production. Installation of the new J73 engine in the future F-86H was slated from the outset. Since this would entail a departure from previous F-86 airframes, two prototypes were included in the production contract, officially approved in May 1951.
Late in 1962 the Air Force reclassified the F-86H as a primary day fighter--coincident with finalization of the fighter-bomber configuration for the F-86F and the emergence of development problems on the urgently needed F-100 day fighter. The F-86H mission change did not affect the production order issued 18 months earlier or the aircraft's planned configuration. No appreciable performance increase was expected from the deletions to be made as a result of this reclassification, since the F-86H would still retain a secondary fighter-bomber capability.
The Air Force had taken delivery of the first YF-86H in January 1953, and of the second one 2 months later. Early flight tests did not uncover any problems serious enough to warrant a major redesign of the new aircraft. However, completion of the Phase II tests in December of the same year confirmed that "numerous deficiencies" existed in both the airframe and power plant. The latter had yet to complete the usual 150-hour qualification test and this alone was a sure indication that F86H allocations to the tactical forces would be delayed.
The F-86H production at the North American Columbus plant began in September 1953 at a very slow rate and, as a result of the YF-86H's aerodynamic and propulsion problems, the Air Force earmarked for testing all 20 aircraft produced through January 1954. Notwithstanding, additional testing time would probably still be needed to test the bombing equipment required by the F-86H day fighter's secondary mission.
The F-86H's high-wing loading and power, deficiencies at high altitudes demoted its role. The J-73 engine generated almost 50 percent more thrust (with only 18 percent more gross weight) but gained little in top speed due to the airframe's Mach limitations. Hence, the F-86H, ordered in 1951 as a fighter bomber, reclassified in 1952 as a primary day fighter, ended up in 1954 as a tactical support fighter-bomber. This did not mark the F-86H--last of the F-86 series as a complete failure. It eventually became a better air-to-ground gunnery platform than the F-86F, with faster climb and acceleration rates. Meanwhile, problems of all kinds plagued the aircraft.
A series of engineering problems delayed the F-86H deliveries. In September a production pool of 58 F-86Hs awaited modifications of one kind or another because of defective gun blast panels, repeated gun jamming, misalignment of the wing spar attaching bolts, defective fire detectors, and a number of other deficiencies of lesser importance.
The delivery of 68 aircraft to TAC's 312th Fighter Bomber Wing at Clovis AFB, N. Mex began the F-86H's role in the US military.
The new J 73 engines were in short supply and this problem was soon compounded by a lack of spare parts. Logistical support of the J-73 became even more difficult following modification of all J-73s to the -3A configuration and the subsequent upgrading of all -3As to the -3D final version. In May 1955 General Electric was 224 production engines behind schedule, the Air Force was unable to satisfy projected engine changes, and logistical support of the engines in use remained critical. In the meantime, to make matters worse, F-86H airframes had to be modified before any of the earlier J-73 engines could be replaced by the new J -73D.
The January discovery that firing the guns dented and cracked various harts of the F-86H structure called for tight flying restrictions that remained in effect through most of the first half of 1955. Engine failures, due to faulty second stage compressor discs made of titanium with an abnormally high hydrogen content, were next. This problem accounted for the loss of two aircraft and the grounding of all F-86Hs equipped with J-73 engines incorporating the faulty titanium items. The F-86Hs were also temporarily grounded on several other occasions either because of their disconcerting ability to shed nose landing gear doors in flight, or because of deficient ejection seats. Nonetheless, although still slated for modification, the F-86H in mid-1956 already encountered fewer operational problems than the F-84F.
Except for the last 10 F-.H6Hs that were modified before leaving the production lines, all F-86H 9 were retrofitted with slatequipped, extended-wing leading edges, similar to those of the F86F. The F-86H's tail pipe also was modified, but the resulting improvement was considered modest for its cost ($13,000 per aircraft). Hence, although there might be future promise in an improved version of tail augmentation, the Air Force cancelled the requirement for further consideration of augmentation--for the F-86H at least. In any case, the F-86H with wing slats and a longer tail pipe proved to have a considerably better performance than the F-86F. The tail pipe augmentation, alone, gave the F86H as much as 10 percent more thrust at sea level.
The Air Force took delivery of its last seven F-86Hs in October 1955. The Air Force accepted 18 F-86Hs in FY 54, 378 in FY 55, and 77 in FY 56 (from July through October 1955). The two YF-86Hs were accepted in early 1953. This was done at a cost of: $582,493.00-airframe, $316,360; engine (installed), $214,612; electronics, $6,831; ordnance, $17,117; armament, $27,573. The cost of
The Air Force quickly disposed of its F-86Hs in favor of the F-100C--TAC's first level flight, supersonic day fighter. In late 1957 the only F-86Hs still possessed by TAC were assigned to a fighter day unit at Seymour Johnson AFB, N.C., and their transfer to the Air National Guard was completed in June 1958.
The Berlin crisis of 1961-62 brought one ANG wing of F-86Hs to temporary active duty. The F-86Hs, deployed to Europe shortly after the 102nd Tactical Fighter Wing was recalled, were armed with conventional weapons. They featured four 20-mm. M-39 guns; six .50 caliber M3s, and four MA-3 launchers. They could carry two M-117 general purpose bombs and two M-116 Napalm bombs.
The Guard operational inventory reached a peak of 168 F-86Hs in 1961 and that aircraft remained an ANG asset for more than a decade. Conversion of the 174th Tactical Fighter Group to the A-3713-type aircraft marked the end of the last F--86Hs in the fall of 1970. The ANG had first received early F-86 models in 1954.
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