The Convair F-112 Delta Spear is a large, long-range, Mach 3+ interceptor that served with the United States Air Force from 1972 to 2002. The Delta Spear is capable of cruising at very high altitudes. It was used frequently to intercept Soviet aircraft approaching the US.

ORIGINS

America had wanted an interceptor capable of Mach 3 flight for some time. Convair's F-106, the "Ultimate Interceptor", failed to meet expectations. Soon after, the U.S. Airforce looked into replacing it. None of Convair's designs, all developments of the F-106, never came off the drawing board.

In the late 50's, North American Aviation designed the XF-108 Rapier. The Rapier was to be an Mach 3 capable, high-altitude interceptor also as a escort for North American's XB-70 Valkyrie bomber. The XF-108 only existed as a wooden mockup when the Department of Defense cancelled it in 1959 due to lack of funds and the fact that the Soviet Union had adopted missiles as their primary means of attack.

A design that really interested the US Air Force, however, was the Lockheed YF-12. It was capable of cruising at 2,000 miles per hour at 80,000 feet, could detect bombers at around 100 miles away, and carried the new Hughes AIM-47 Falcon missile that could hit a target at a distance of over 100 miles. The YF-12 was modified over time to make it fly better. It looked very promising, and the then-Air Defense Command ordered 93 improved F-12Bs with more powerful radars.

However the F-12 was suddenly canceled in 1968 because of Secretary of Defense Robert McNamara's decision to hold back funding for three years due to the Vietnam War and updated intelligence that deemed that the F-12 was no longer needed.

THE DELTA SPEAR

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In the late 60's Convair wanted to build a competitor to the F-12, something better. However, they ran into difficulty trying to figure out what kind of design they wanted.

Suddenly, out of the blue, in 1965, North American offered to sell technical aspects, aerodynamic readouts, and other data from the XF-108 and XB-70 programs as well as all patents relating to the designs and the designs themselves. North American offered a low price, due to them needing quick funds for a new program. Convair, jumping at the chance for new design possibilities, bought North American's property package.

With the new wealth of knowledge they had, Convair got to work. They now looked to BAC-Aerospatiale's Concorde supersonic airliner. Convair decided to give a long, curved delta wing to the new fighter.

Convair came up with a large fighter with massive engines under the fuselage and a large, sweptback fin. Canards were determined to be not necessary. The wings incorporated the XB-70's drooping wingtips. The new fighter would be powered by General Electric YJ93 turbojet engines, the same engines that would've powered the XB-70 and the XF-108. Missiles would be carried on the fighter's belly. The fuselage would be sleek all around.

The fighter would have a two-crew cockpit, the Pilot in the front and the Radar Intercept Officer in the back who would operate the radar and missiles. It would carry the Hughes AN/ASG-19 fire control system, a derivative of the AN/ASG-18 originally developed for the F-12 but stronger and with infrared search-and-track sensors in the fusleage instead of on the chines.

In 1967 the aircraft was designated Model 190 by Convair. By then, Convair incorporated something new into the design: countermeasures, which could spoof enemy radar. They hoped to use it to their advantage over the F-12.

When the F-12 was canceled in 1968, Convair was alarmed. They thought that the U.S. Air Force would not show interest in the Model 190. Convair decided to hurry up and show them the aircraft.

THE DELTA SPEAR FLIES

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On March 18, 1969, Convair finished the prototype Model 190. It was presented to the USAF two days later. It was designated as the XF-112.

Everyone who saw the XF-112 was amazed at its design. It looked nothing like any other aircraft the US had at the time. The USAF was intrigued enough to make a program to test the XF-112's capabilities.

The XF-112 first took flight on June 3, 1969. The pilot, John Eabest, said that it was easy to fly, and remained straight as a rock in the air. The XF-112 made 4 more flight tests before it exceeded Mach 1 in the 8th test. The 10th test was to be made at full power at 30,000 ft. The XF-112 demonstrated its ability to cruise at high speed. On the 12th test, it reached its maximum speed of 1,684 miles per hour, a disappointment for Convair, which had envisioned a Mach 3 capable aircraft. The USAF was also disappointed.

The XF-112 lacked radar or armament, so in a last-ditch effort Convair made the XF-112A with the AN/ASG-19 radar and the capability to carry the AIM-47 Falcon missile. The U.S. Air Force carried out 9 tests with the XF-112A. The USAF simply stated that the F-112 did not perform significantly well to warrant purchasing them and the upcoming F-15 Eagle.

DELTA SPEAR REBORN

Convair was disappointed at the performance of the F-112. However, they still kept it alive in case it was needed.

In 1970 the Soviet Union, tired of just sitting around, began to develop new bombers and mass-produce others. Their idea was while the US was focused on ICBMs, they would attack with a bomber armed with missiles. The US, alarmed, suddenly had a need for interceptors. However, new missile technology enabled bombers to launch missiles outside the range of fighters like the F-4 Phantom II. The USAF wanted a fighter that could fly very fast from place to place and destroy bombers before they were in range of the continental US.

Convair was not too excited, because the F-112 wouldn't go fast enough. However, a breakthrough came when General Electric created the YJ94 turbojet engine with 35,000 pounds thrust wet. Convair did some quick calculations and discovered that the F-112 with YJ94s could reach over 2,000 miles per hour. They quickly ordered lots of YJ94s.

The new F-112 was equipped with General Electric J94 engines and the brand-new Hughes AN/APG-63 radar later carried on the F-15. Changes to the cockpit and control surfaces were also done. It was presented to the USAF on August 3, 1971 and designated YF-112B. It was named "Delta Spear."

The YF-112B reached 85,000 ft in the 7th test and 2,128 miles per hour in the 14th test. The U.S. Air Force was impressed. The YF-112B was ordered for the Aerospace Defense Command as the F-112B. On April 21, 1972, the first F-112B went into operation with the First Air Force of the Aerospace Defense Command.

DESIGN

The F-112 Delta Spear is the largest fighter ever flown by the U.S. Air Force. Its large wing stores a lot of fuel which allows it to fly long distances. The Delta Spear was the only aircraft to operationally carry the Hughes AIM-47 Falcon long range air-to-air missile.

An unintended result of the usage of General Electric J94 engines is that the F-112 was one of the first aircraft to be capable of supercruise. The J94 had a new nacelle to stabilize the aircraft.

OPERATIONAL HISTORY

The Delta Spear has shot down two aircraft in service. One, in 1974, was a unidentified aircraft that was firing weapons at the US. The crew of F-112 #18-3882 saw the aircraft as a threat. They launched an AIM-47 at a distance of 82.7 miles. The missile destroyed and the aircraft. No country or group of any kind have taken responsibility for the downed aircraft.

The other aircraft was an out of control QB-47E target drone flying out of control over Arizona towards Prescott in 1976. Its trajectory indicated that it would crash in Prescott. Nearby F-112 #34-1128 was notified about the situation and shot down the bomber, which crashed in the desert, before it reached Prescott.

The Delta Spear was used an innumerable amount of times to intercept Tupolev Tu-95RT "Bear-D" reconnaissance bombers approaching the US. Unlike the F-12, It could perform the standard interception procedure of flying along with the intercepted aircraft back where it came from.

In 1980 the Delta Spears were transferred to the Air Defence, Tactical Air Command unit of the Tactical Air Command. General Dynamics modified the F-112s to carry Hughes AIM-47 Phoenix missiles and have the AN/AWG-9 radar from the F-14 Tomcat. All but 10 Delta Spears were converted to the "C" model.

The F-112s were transferred to the First Air Force in 1990 when the Air Defense, Tactical Air Command was deactivated. All Delta Spears were allocated to Air National Guard units in 1995.

In 2001, the USAF decided that the F-112 had lesser survivability in modern environments and was expected to be replaced by the upcoming F-22 Raptor. 200 Delta Spears were retired in October 2001 and the rest on July 2, 2002.

VARIANTS

Convair built 590 F-112s for the USAF. The Delta Spear was never marketed to other countries.

XF-112
Original version. No radar or provision for weapons. Equipped with General Electric YJ93 engines.

XF-112A
XF-112 with Hughes AN/ASG-19 Fire Control System and capable of carrying AIM-47 Falcon missiles, Did not see service.

F-112B (Includes YF-112B)
Production version with General Electric J94 engines and Hughes AN/APG-63 radar. Capable of Mach 3 flight.

F-112C
1980 upgrade with AN/AWG-9 radar and the ability to carry AIM-54 Phoenix missiles. All but 10 converted.

SPECIFICATIONS

Top speed: 2,254 mph (lore)
~2,100 (in-game)

Powerplant: General Electric J94 engines with 15,500 lbs. thrust dry, 35,000 lbs. thrust wet

Avionics: Hughes AN/APG-63 (F-112B), Hughes AN/AWG-9 (F-112C)

Armament: 6× Hughes AIM-47 Falcon air-to-air missiles (F-112B) Hughes AIM-54 Phoenix (F-112C, AIM-54A 1980-1986, AIM-54C 1986-2002)

INSTRUCTIONS

AG1: drag parachute
AG2: afterburner.

In Aerospace Defence Command Grey, instead of Very Very Light Grey.

I hope you enjoy this "What If" build. 😀

Credit to Leehopard for the plane, and and BurkeAircraft1 for the AIM-47s.

P.S. I will be doing edits on the description over time.