This slight shift farther back from the missile’s normal ‘hot’ aiming point actually made the difference in the two aircraft’s survivability
For more than ten years, Israel depended on France as its main source of weaponry. By the mid-1960s, however, the country was seeking more advanced and capable US-made weapons. This led to the purchase of the combat-proven Douglas A-4 Skyhawk for light strike missions. An initial order for 48 A-4Hs was placed in 1966, and these aircraft soon became the core of the Israeli Air Force’s attack fleet.
The Skyhawk entered Israeli service two years later and was nicknamed the Ahit, or Eagle. It flew thousands of missions during the 1967–70 War of Attrition against Egypt, and clashes along the Lebanese and Syrian frontiers also prompted Ahit deployments. By 1973, Israel had brought in additional A-4 variants, and in October that year, five Skyhawk squadrons took part in combat during the Yom Kippur War.
Over 50 Skyhawks were destroyed during the 19-day war, a consequence of the attack squadrons undertaking dangerous multi-role missions and the widespread use of mobile and shoulder-fired SAMs.
As Shlomo Aloni notes in his book Israeli A-4 Skyhawk Units in Combat, in addition to adopting more refined attack profiles and better evasive maneuvers, Skyhawk pilots started deploying chaff bundles to disrupt radar-guided SAMs. Flares were later incorporated into the chaff dispensers to counter heat-seeking SAMs as well, but these were not yet in service during the Yom Kippur War. Even so, anti–heat-seeking SAM defenses for the Skyhawk were quickly fielded during the final stages of the conflict.
In 1968, the IDF/AF began an upgrade program for the Super Mystere that involved replacing its engine, swapping the French Atar 101 for the American Pratt & Whitney J52. One key reason for this change was a commonality with the J52-powered Skyhawk, which was entering service as the Super Mystere’s successor. To install the J52 in the French attack aircraft, extensive structural changes were required because the engines differed in size and weight. The original French engine also had an afterburner, whereas the J52 did not. As a result, the upgraded Super Mystere’s exhaust had to be redesigned with an extended tailpipe that projected well behind the aircraft’s vertical and horizontal tail surfaces.
During the Yom Kippur War, upgraded Super Mysteres and Skyhawks carried out comparable missions and encountered the same threats. However, the enhanced Super Mystere suffered fewer shootdowns and less damage from SA-7 heat-seeking missiles. Wartime analysis of this phenomenon indicated that the modified tail-pipe of the improved Super Mystere kept the explosion of the missile’s proximity-fused warhead away from the vital parts of the jet. This relatively small rearward shift from the missile’s usual ‘hot’ aiming point ultimately proved decisive for the differing survivability of the two aircraft.
The A-4’s nozzle ended well ahead of the tail section’s vertical and horizontal flying surfaces, so when a missile’s proximity fuse exploded the warhead slightly behind the nozzle, the resulting fragments sprayed the Skyhawk’s tail section, holing the flying surfaces and puncturing the crucial hydraulic fluid pipes.
A proposal from frontline units prompted No. 22 Air Maintenance Unit at Tel Nof to develop a tailpipe modification for the Skyhawk. It came up with a nozzle extension that, in plan view, ended behind the rear of the tail section’s vertical and horizontal flying surfaces, as with the improved Super Mystery. The modification was rapidly conceived, and No. 22 Air Maintenance Unit produced a prototype installation. Test pilots from the Flight Test Centre then carried out four flights in the modified Skyhawk within 24 hours, after which the change was approved for squadron use. Just 24 hours later, the modification was in operational service.
Informally referred to within the IAF as the “Barrel,” the first Skyhawk slated to receive this modification was flown from Tel Nof to the Israel Aircraft Industries facility at Lod Airport on the evening of October 20, 1973. The Barrel-modified A-4N was delivered back to No. 115 Squadron the following morning.
Israeli A-4 Skyhawk Units in Combat is published by Osprey Publishing and is available to order here.
Photo by Israeli Air Force and Oren Rozen via Wikipedia
