It was only last August 2015 that:
The Syrian government has received six MiG-31 ‘Foxhound’ interceptor aircraft from Russia under a deal that was said to have been signed in 2007, a regional media source has reported.
The aircraft recently arrived at Mezze Airbase on the outskirts of Damascus, the Turkish BGN News agency reported on 16 August.
Syria was reported to have ordered eight MiG-31 combat aircraft as part of a wider defence deal with Russia in 2007. Although this deal was confirmed at the time by the head of the United Aircraft Corporation (UAC), Alexei Fyodorov, it was later denied by Anatoly Isaykin, director of state arms export bureau Rosoboronexport, who in 2010 described the sale as “a journalistic hoax”. Neither the Russian nor the Syrian authorities have so far commented publicly on the reported deliveries.
The MiG-31 first entered Soviet service in the early 1980s as a long-range, high-altitude, and high-speed interceptor. Although relatively old, it is still a highly capable platform that features some of the latest sensor and weapons fits.
In particular, the MiG-31’s NIIP N007 S-800 SBI-16 (RP-31) Zaslon or Zaslon-A electronically scanned phased-array fire-control radar (NATO codename ‘Flash Dance’) affords it an impressive beyond-visual range capability, enabling it to see airborne targets out to a range of 108 n miles (200 km; 124 miles) in a clutter-free forward sector, or 48 n miles (90 km; 56 miles) to the rear. It is capable of tracking 10 targets and attacking four simultaneously. Coupled with this radar, the MiG-31’s R-33 (NATO codename AA-9 ‘Amos’) or R-37 (AA-X-13/AA-13 ‘Arrow’) long-range air-to-air missiles afford it a highly potent beyond-visual range (BVR) air-to-air capability.
According to IHS Jane’s World Air Forces , Russia has approximately 200 MiG-31s in service that it is currently in the process of upgrading to keep them operational through to the 2030s. With the exception of Russia and now possibly Syria, only Kazakhstan flies the type.
COMMENT
Until the arrival of the MiG-31s in Damascus is confirmed, it should be treated with an element of scepticism. With the regime of Bashar al-Assad finding itself increasingly hard-pressed on the ground, it has to be noted that a state-of-the-art high-altitude interceptor is probably of limited use right now.
The delivery has been linked to Western proposals for a no-fly buffer zone to be established over Syria, but while the MiG-31s would certainly give NATO planners pause for thought, their small number and single basing location would mean that they would likely be destroyed in the early hours of any alliance effort to establish air dominance over the country ahead of implementing such a no-fly zone.
This surely keeps the United States out of the Syria Islamic State, Jabhat al Nusra war theater.
MOSCOW (AP) —Russian warplanes in Syria have flown their first joint combat mission with the Syrian air force, Russia’s Defense Ministry said Thursday.
The Defense Ministry said that a pair of Syrian MiG-29 fighter jets escorted two Russian Su-25 ground attack aircraft during Thursday’s mission.
The ministry said that Syrian pilots had previously visited the Russian base to discuss details of the mission. It released a video showing the Russian planes taking off from Hemeimeem air base and being joined in flight by the Syrian jets.
Russia has conducted an air campaign in Syria since Sept. 30. Moscow has insisted that Russian warplanes are focusing their strikes on the Islamic State group and other extremists, but the U.S. and its allies say they also hit moderate groups fighting Syrian President Bashar Assad‘s army.
Agreement between the Russian Federation and the Syrian Arab Republic on the stationing of an aviation unit of the armed forces of the Russian Federation on the territory of the Syrian Arab Republic on August 26, 2015 year (temporarily applied with August 26, 2015 onwards)
Reuters: Russia is allowed to deploy its air force in Syria for an open-ended period under the terms of an agreement signed between Moscow and Damascus in August, the RIA news agency said today, citing the text of the document.Russian planes flying out of a base in Syria’s Latakia province have been bombing Islamic militants since September 30 as part of a push to help Syrian President Bashar al-Assad defeat his opponents on the battle field.REUTERS SHS AN2241
Bloomberg: Russia’s military is operating in Syria without a time limit under an accord between the two governments, which also agreed to a one-year notice period for either side to terminate the pact, according to the text of the deal dated Aug. 26 and published Thursday.
The document also states that Russia bears no responsibility for any damage it causes during the operation and that the Syrian government will have to settle any disputes against the Russian aviation group from third parties, according to the agreement, signed in Damascus last year and now published by the Kremlin.
Russian personnel have diplomatic immunity under the deal and Syrian authorities can’t enter their base without the permission of its Russian commander. They are also not allowed to inspect Russian shipments into the country or search Russian planes, it says.
President Vladimir Putin launched the air campaign on Sept. 30 and doubled the fleet of warplanes involved in bombing missions to about 70 in November. Russian bombers made more than 5,500 sorties since the strikes began, according to the Defense Ministry in Moscow.
More historical data on Jabhat al Nusra is found here.