The FAA previously issued a Notice to Airmen (NOTAM) strongly suggesting pilots avoid the area, but the new report and lack of traffic over the area moved it to impose a ban.
"Based on an updated assessment of the risk associated with such operations and the lack of any requests from operators wishing to fly in this airspace, we believe it prudent to prohibit U.S. operators from flying into, out of, and over Syria. The ongoing armed conflict and volatile security environment in Syria poses a serious potential threat to civil aviation. Armed extremist groups in Syria are known to be equipped with a variety of anti-aircraft weapons which have the capability to threaten civilian aircraft," said the FAA in a statement Monday.
A month after the downing of Malaysia Airlines Flight 17 over Ukraine, Small Arms Survey published a briefing warning of the extremist militant possession of man-portable air defense systems (MANPADS).
Monitors have seen at least eight different MANPADS, three that had never been seen outside of government control. The systems are reportedly of Chinese and Russian-Soviet design. Russian support of the Syrian government has recently been a point of contention with the U.S. Despite Russian claims to the contrary, Small Arms Survey said there is no known evidence that the extremist groups have possession of U.S. systems.
"International transfers of MANPADS to armed groups in Syria violate resolutions, guidelines and agreements adopted by several multilateral organizations," read the report.
The group warned the "porosity" of the Syrian border, instability in the region and anti-aircraft weapons placed in the wrong hands could lead to "catastrophic consequences."
"The most obvious implication -- and the one that has received the most media attention -- is the potential threat posed by the diversion and misuse of MANPADS in Syria. Weapons acquired by arms groups are generally more vulnerable to theft, loss and diversion than weapons held by governments, and the use of diverted MANPADS against commercial airliners could have catastrophic consequences."