ORLANDO, Florida — The Air Force's effort to build, rebuild and expand airfields in Iraq and Syria is a central element of the coalition's push to defeat the Islamic State, the deputy commander of U.S. Air Forces Central Command said Thursday.

Maj. Gen. Jay Silveria said that an airfield in northern Syria — the Air Force would not say on the record exactly where — and the Qayyarah West Air Field near Mosul, Iraq, are "key for setting a posture for the fight to continue" against ISIS.

About 500 U.S. combat advisers are in Syria coordinating efforts to destroy the Islamic State, while about 5,000 American troops are deployed to Iraq.

The Syrian airfield began as "a flat spot on the ground," Silveria said during a meeting with reporters at the Air Force Association's Air Warfare Symposium.

Over time, engineers from Air Mobility Command lengthened it and are still building it out today, he said.

"The longer we made the runway, that allowed more cargo weight to be brought in," Silveria said. "We were accelerating the number of sorties. [Having a runway in northern Syria] gave us the access to start to bring in supplies, ammunition, for our own forces, for opposition forces, etc, in the entire area."

Last week, the runway in Syria saw its 50th C-17 landing, Silveria said. It has also seen more than 100 C-130 sorties. And without that runway, "we'd be operating at much greater distances and it'd be much more difficult to get into Syria."

The Qayyarah West Airfield has similarly proved to be a vital staging area for the battle in Mosul, Silveria said. Without it, he said forces would have had to move from much further south to try to force ISIS out of the strategically key city.

But when ISIS was forced out of Q-West last July, Silveria said, it was "a shambles." 

During their two-year occupation of the strategically crucial airfield, ISIS dug trenches in it, tore it up with an excavator-mounted jackhammer, littered it with massive concrete T-walls, and detonated explosives to riddle it with craters. 

They dumped debris in the holes and left the airfield booby-trapped with deadly explosives. And they destroyed or severely damaged facilities such as the air traffic control tower. 

The airfield had to be swept six times for hidden ISIS bombs — three times by Iraqi forces and then three more times by coalition troops. The Iraqis had to bring in a crane to lift the T-walls off the runway and reposition them as defensive barriers. 

An intense three-week repair effort by 29 airmen from the 1st Expeditionary Civil Engineering Group — which included putting down nearly 2 million pounds of cement to repair the runway —  got the Iraqi airfield in shape in October, around the time the Mosul battle began.

Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.

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