Northrop F-5 RF-5E Tigereye

The RF-5E Tigereye was the dedicated reconnaissance version of the F-5E Tiger II, and it began as a Northrop private venture. At first the company only intended to give the F-5E a limited reconnaissance capability by fitting an RF-5A-type nose carrying four KS-121A cameras. Such a nose was actually installed on a few Saudi F-5Es, but the modification took 100 man-hours to perform and even longer to undo. By the mid-1970s, moreover, the F-5E nose was too small to carry the most modern reconnaissance equipment.

Northrop chose to design a completely new nose section, longer than the fighter's, with 26 cubic feet of volume (about 0.74 m³): nine times the space available in the nose of the RF-5A. The stated aim was a reconnaissance aircraft with the same capability as the RF-4E Phantom in a much smaller and cheaper airframe, aimed at F-5E operators who could not afford a separate type dedicated to the mission. A KS-87B camera could be mounted in the extreme nose, behind an optically flat window. To make room for the sensors the fighter's radar was removed, and on production aircraft one of the two 20 mm cannon was deleted as well, so the Tigereye kept a single gun and remained combat capable, with provision for two AIM-9 Sidewinder missiles.

The test vehicle was F-5E 74-1420, which Northrop had leased back from the USAF. It received the new stretched nose and, unlike production aircraft, retained both 20 mm cannon. It flew for the first time on 29 January 1979, piloted by Darrell Cornell, and flight evaluation took place at Edwards AFB. Once testing was complete it was converted back to standard F-5E configuration and sold to Brazil. In principle the Tigereye nose could be retrofitted to an F-5E fighter, but this required strengthening several fuselage keel beams and was not cost-effective.

Northrop anticipated a worldwide market for 100 to 150 Tigereyes, but only a handful were ordered. The first customer was Malaysia, which ordered two aircraft (US serials 80-333 and 80-334), registered in the Royal Malaysian Air Force as M29-19 and M29-20. English Wikipedia places their arrival in 1983; the USAF acceptance table reproduced by German Wikipedia records them in 1986. Saudi Arabia became the second customer in 1982, ordering ten examples (serials 84-194 to 84-203), which replaced Saudi F-5Es fitted with the earlier F-5A-type camera nose. As a result only twelve RF-5Es were built. Part of the reason for such disappointing sales was price: a Tigereye cost 50 percent more than a standard F-5E fighter.

According to the data compiled by Skytamer, the RF-5E was 15.09 m long (over the pitot), with a wingspan of 8.128 m (over the wingtip rails) and a height of 4.069 m, and a wing area of 15.63 m². Empty weight is estimated at 4,800 kg and maximum take-off weight was 11,510 kg. It was powered by two General Electric J85-GE-21 turbojets rated at 16 kN military thrust and 22 kN with afterburner each. Maximum speed was Mach 1.54, with an estimated maximum range of 2,400 km and an estimated combat ceiling of 16,310 m.

The Tigereye had a second life away from Northrop's line. In 1990-1991, using jigs and tooling purchased from Northrop, Singapore Aircraft Industries (now ST Aerospace) converted eight Republic of Singapore Air Force F-5Es into the RF-5E Tigereye variant. They went to No. 141 "Merlin" Squadron, which traded its Hawker Hunter FR.74S for them in 1992 and was based at Paya Lebar. In 1998 the eight aircraft received the upgrade applied to the rest of the fleet (except for the radar) and were redesignated RF-5S, a variant with its own page, as is the Taiwanese RF-5E Tigergazer, a separate conversion programme of seven F-5Es.