Tehran has permitted the Russian military to use its Third Tactical Fighter Base (TFB.3) near the city of Hamedan for “temporary basing” of the Tupolev Tu-22M3 and Sukhoi Su-34 strike aircraft. Thus, for the first time since the Islamic Revolution of 1979, which resulted in the expulsion of foreign soldiers, Iran has welcomed Russians back into the country in a move that could have serious consequences for the balance of power in the oil-rich Middle East.

Russian aircraft arrived at the Iranian air base on August 15 and flew first combat missions the next day, bombing Islamic State and Jabhat An-Nusra targets in the Syrian provinces of Aleppo and Deir Ezzoir.

To reach targets in Syria, the Tupolevs had to overfly Iraq, whose government was quick to issue the requested permission. “Russian bombers can cross the Iraqi airspace provided they meet certain conditions,” Iraqi Prime Minister Haider al-Abadi stated. “We have opened a certain corridor for the Russian bombers but do not permit them flying over Iraqi cities.”

Hamedan, home to the Iranian air force 301, 303 and 304 squadrons, is the second foreign base to host Russian Aviation and Space Force (VKS) units involved in the bombing campaign against militants after Khmeimim, in the Syrian province of Latakia.

The latter base has been used by the Russian expeditionary group since September 2015. At peak activity, the VKS kept up to 70 combat jets and helicopters there. Currently, Khmeimim provides basing for Su-30SM and Su-35S multirole fighters, Su-24M and Su-34 interdiction aircraft, and fire support and transport helicopters.

Recently, Moscow and Tehran have taken significant steps to strengthen their military ties. In May, Iran started taking deliveries of S-300 long-range surface-to-air missiles. Iran-backed Shia militia in Syria began operating Russian-made T-90A main battle tanks. “Iran agrees to share with Russia its infrastructure for the purpose of fighting terrorism in Syria,” according to Ali Shamkhani, secretary of the Supreme National Security Council, who called the cooperation between Tehran and Moscow a “strategic partnership.”

Operational since 1983, the Tu-22M3 (NATO codename Backfire) is a supersonic swing-wing bomber, unofficially classified as “Eurostrategic” as it lacks range for intercontinental missions following removal of in-flight refueling systems as part of U.S.-Russia disarmament treaties. The type has been employed by VKS on strike missions in Syria since November, operating out of the Mozdok and Engels air force bases in southern Russia. Typically, a Tu-22M3 carries 12 OFAB-250-270 free-fall fragmentation bombs, each weighing about 600 pounds.

Basing at TFB.3 dramatically reduces the time and distance to targets, considerably cutting operational costs and saving on service life of the attacking aircraft. It also allows for a considerable increase in the weapons load on a typical mission. Operating out of TFB.3, a Tu-22M3 can take up to 12 tons of bomb, drop them on Deir Ezzor (distance to target 700 km), Palmyra (900 km) or Aleppo (1000 km) and return to Hamedan on internal fuel. If necessary, a Tu-22M3 can additionally take nine OFAB-250-270s on each of four external rack, bringing their grand total to 69, and drop them on targets along the Euphrates river. Alternatively, the bomber can take 42 FAB-500M62s, each weighing 1,100 pounds.

The VKS seems to have started using the Tu-22M3M version of the bomber, a recent upgrade with newer, more precise navigation and sighting systems,for Syrian airstrikes. The “M3M” is believed to have a new passive electronically scanned array radar modeled from that in use on the Su-30SM and Su-35S.

A Tu-22M3M is useful as a lead aircraft for older bombers in a formation, enabling more accurate “carpet bombing” for the entire group. Overall, the efficiency and lethality of Russian aviation in Syria has received a considerable boost, which may soon prompt the Russian-backed Syrian Arab Army and its allies to launch a new wave of offensive operations against opposing forces.