In 1976, the Lebanese Civil War had been raging for a year when the Syrian military poured across the border into the region to ostensibly stabilize the situation. Securing the Bekaa Valley and the main Beirut-Damascus highway that crossed the central part of the country with massive numbers of troops and armor, soon the Palestinian Liberation Organization (PLO) and its Muslim allies in Lebanon were receiving support from the Syrians. To cover the Syrian left flank facing Israel, the Syrian 10th Armored Divsion was arrayed across the Bekaa Valley with three brigades of surface-to-air missile units to protect them from an Israeli attack. A total of 19 batteries covered the valley consisting of two SA-2 batteries, two SA-3 batteries, and fifteen new SA-6 batteries. During the next several years the Israelis provided support to the Christian factions in the civil war while maintaining a close eye on the strengthening Syrian integrated air defense system (IADS) that stretched across the Bekaa Valley. Overflights to pinpoint the SAM sites required use of Firebee recon drones due to the dense air defense network that the Syrians had established. In the late May to early June of 1982, the PLO conducted a 12-day artillery and rocket attack on northern Israel that resulted in 60 civilian casualties. The last straw for the Israelis came on 3 June when the PLO attempted to assassinate in London the Israeli ambassador to the United Kingdom.
On 6 June, seven Israeli mechanized divisions with 60,000 troops and 500 tanks crossed into southern Lebanon in three prongs- one up the coastal plain, one through the central mountains, and a third push into the Bekaa Valley to keep the Syrian 10th Armored Division from intervening against the Israeli right flank. On the first three days of the ground invasion, seven Syrian MiG fighters were shot down. By 8 June Israeli forward elements were at the entrance to the Bekaa Valley but weren't able to push any further north as the Syrian forces held steady under the protective umbrella of their IADS, denying close air support to the Israeli ground forces. For several weeks prior to the invasion, though, the IDF/AF had been planning to deal with the Syrian IADS umbrella over the Bekaa Valley. Years of meticulous reconnaissance and eavesdropping gave the IDF/AF the locations, operating frequencies and modes of the SAM batteries in the valley. Operation Drugstore was their plan for not just the suppression of enemy air defenses (SEAD) but what was being called "DEAD"- destruction of enemy air defenses. This is what made Operation Drugstore a landmark operation in air combat- prior to 1982, suppression was the name of the game as it had been practiced in Vietnam by the United States- keep the enemy's heads down while strike packages went in and hit targets. For Israel, nothing less than the complete elimination of the Syrian IADS was acceptable- air superiority against the Syrian fighters was meaningless if the IADS prevented close air support from assisting the ground forces' objectives.
The opening phase of Operation Drugstore saw large numbers of Delilah ground-launched drones being launched towards the Bekaa Valley, giving the impression of a large Israeli strike force. As the SAM batteries went active to engage what they thought were Israeli aircraft, battlefield surface-to-surface missiles were fired at each SAM battery. One of the missiles used was the Keres, which was an Israeli modification of the AGM-78 Standard anti-radiation missile used by Wild Weasel aircraft. The mobile launcher fired three Keres missiles and even a local modification of the smaller AGM-45 Shrike was used that added a second stage booster to allow a ground launch. In the first ten minutes of the operation, ten of the 19 batteries had been knocked out either due to missile hits or because they had run out of missiles engaging the Delilah drones. Four minutes later, the first wave of ground attack aircraft swept into the Bekaa Valley- 26 McDonnell Douglas F-4E Phantoms and a similar number of IAI Kfir C2s, with the Phantoms using AGM-65 Maverick missiles as well as Shrike and Standard ARMs to hit the remaining SAM sites while the Kfirs targeted the control vans and storage areas of the missile sites. With no losses, a second wave of over forty A-4 Skyhawks and IAI Kfir C2s swept in attacking the SAM sites with cluster bombs while the F-4Es returned using laser-guided bombs against any surviving control vans. In just two hours, 17 of the 19 Syrian SAM sites had been destroyed.
The next phase of Operation Drugstore saw Israeli strike aircraft next hit the Syrian mobile GCI (ground-controlled intercept) sites that provided directions to the Syrian MiG force. With the destruction of the GCI sites and their radars, the Syrian IADS was now blinded as F-15 Eagles and F-16 Fighting Falcons established combat air patrols over the Bekaa Valley. The timing was perfect- as the Syrian commanders realized that their IADS umbrella was being systematically demolished, three squadrons of MiG-21s and MiG-23s were scrambled from their Syrian bases- it's estimated that up to sixty Syrian fighters raced to the Bekaa Valley where the F-15s and F-16s were waiting. They were tasked to hit the Israeli strike forces that were attacking the components of their IADS, but instead found that Israeli Grumman E-2 Hawkeyes orbiting over southern Lebanon had given the combat air patrols ample warning of the inbound MiGs. Because the Syrians relied on GCI controllers to provide them with vectors and targeting information, the loss of the GCI sites meant they were flying into the Bekaa Valley blind while the F-15s and F-16s' longer ranged radars already had them targeted. With communcations and radars being jammed, most of the Syrian MiGs never saw what hit them- ten MiG-21s fell within minutes. At the end of the day, only one F-15 had been hit, and the pilot managed to recover his Eagle safely to Ramat David AB in northern Israel.
The following morning the last two Syrian SAM batteries were destroyed while the Syrians scrambled more MiG-21s and MiG-23s to make up for the previous day's losses. Since the MiG-23 Floggers were the most capable of the Syrian fighters, the F-15s were tasked with eliminating them and six were shot down in short order. As Israeli armored units engaged Syrian armor in the valley, two waves of Syrian Sukhoi Su-22 fighter bombers were sent into to attack the Israeli units, escorted by a squadron of MiG-21s. It was a turkey shoot as over 20 Syrian aircraft were shot down by the Israeli fighters patrolling the skies of the Bekaa Valley. The Syrians then tried to send in anti-tank Gazelle helicopters to go after the Israeli armor and those were shot down as well.
11 June was the last day of continuous fighting as a cease fire was to go into effect later than day. Hoping to stave off defeat and entering the ceasefire at a disadvantage, the Syrians poured their MiG-23 Floggers into the battle against the F-15s and F-16s, leaving the MiG-21s to escort the strike version of the Flogger, the MiG-23BN. Several Syrian MiG-25 Foxbats made high altitude runs over the Bekaa Valley, hoping to distract the Israeli fighters into looking "upward", distracted from the inbound MiG-23s. At lower altitudes, two waves of Syrian MiG-23BNs would attempt to hit the Israeli armored units once again where the Sukhois had failed the previous day. The Syrian fighter sweep failed as their presence was once again known thanks to the E-2 Hawkeyes. Six Floggers were shot down in their first pass over the valley. Another six MiG-21s were shot down as well and the MiG-23BN attacks had little effect on the Israeli positions.
By the time of the ceasefire took effect, the Syrians lost 30% of their air force in just one week of fighting for a total of 88 aircraft shot down. Of those 88 kills, 44 belonged to F-15 Eagles and 33 belonged to F-16s. Israeli losses have never been fully admitted, but it's believed to include one F-16, one F-4E, one Kfir C2, two A-4s and several helicopters. Following the battle in the skies over the Bekaa Valley, the Israeli Defense Forces Air Force (IDF/AF) was secretly debriefed by US military experts from the US Air Force and other branches of the military. The lessons gleaned from Operation Drugstore would strongly influence Coalition tactics on the opening night of Operation Desert Storm. In what was called "Poobah's Party" (from the callsign of Brigadier General Larry Henry, a leading USAF tactician and expert on air defenses), approximately one-hundred drones were fired from ground sites in Saudi Arabia to trigger the Iraqi IADS into action to they could be targeted for destruction by Coalition air assets. With the stealthy Lockheed F-117A Nighthawks going "downtown" to Baghdad to take out the command and control centers of the IADS, individual radar and SAM sites then were left on their own to find their own targets in the midst of some intense jamming. Iraqi radar sites could burn through the jamming, and when they did, they detected the drones of Poobah's Party. Sites that hadn't expended their missiles on the drones found themselves targeted by F-4G Wild Weasels.
Source: F-15 Eagle Engaged: The World's Most Successful Fighter by Steve Davies and Doug Dildy. Osprey, 2007, p146-147.