The US Federal Aviation Administration (FAA) has raised the possibility that Russian electronic warfare systems in Syria could disrupt commercial flights.
The FAA posted a notice to airmen (NOTAM) on 9 October warning them to "be aware of possible loss of GNSS [global navigation satellite system] signal within Beirut FIR [flight information region] due to unforeseen reason". It recommended pilots use standard terminal arrival route (STARS) procedures when landing at Beirut's international airport.
The NOTAM was posted after Russian Defence Minister Sergei Shoigu announced on 2 October that additional electronic warfare systems had been deployed to Syria and switched on.
NBC News reported in April that Russian electronic warfare systems were being used to jam the GPS receivers on smaller unmanned aerial vehicles (UAVs) that the US military is using in eastern Syria.
Shoigu also said that S-300 strategic air defence systems had been delivered to Syria. He did not identify the specific variant or numbers involved, but indicated that they will be operated by Russian crews when he said that it would take three months to train Syrian personnel.
The Tass news agency reported on 8 October that three S-300PM systems had been given to Syria free of charge.
"On 1 October three battalion sets of S-300PM systems of eight launchers each were delivered to Syria," it quoted a military-diplomatic source as saying. "These systems were previously deployed at one of the Russian Aerospace Forces' regiments, which now use the S-400 Triumf system. The S-300 systems underwent capital repairs at Russian defence enterprises, are in good condition, and are capable of performing combat tasks."
The source added that the deliveries included more than 100 missiles for each battalion.
The deployment of additional air defences was Russia's response to the Syrian military shooting down one of its Il-20M intelligence-gathering aircraft on 17 September, a loss it blamed on the presence of Israeli strike jets.
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