The phrase "a formidable air" is correct and usable in written English.
It can be used to describe someone or something that has a strong, impressive, or intimidating presence.
Example: "The speaker entered the room with a formidable air, commanding the attention of everyone present."
Alternatives: "an imposing presence" or "a powerful demeanor".
With losses throughout his roster and coaching staff, a formidable air of uncertainty will sweep through Madison this off-season and the specter of another Rose Bowl loss will loom over it all.
"It would be a formidable air campaign, but it could be accomplished," Deptula said.
On top of that, the Saudis have a formidable air force that flies American-made F-15s. .
In the Vietnam War the North Vietnamese deployed a formidable air-defense system based on Soviet-made anti-aircraft guns and SA-2 surface-to-air missiles (SAMs).
But if Russia responded to NATO preparations by announcing a no-fly zone, backed by its formidable air defences and bristling arsenal of tactical nuclear weapons, the stakes would quickly become dangerously high.
The Pentagon is talking about Syria's allegedly formidable air defenses.
The insurgents fear that without such cover, they would be vulnerable to attacks by Syria's formidable air force.
The Russians have deployed formidable air power since September to help the forces of President Bashar al-Assad of Syria, who had been ceding ground.
Large scale green production of poly(oxymethylene) dimethyl ethers DMMn) would be crucial if the diesel-DMMn blends were applied to tackle the worldwide formidable air pollution by particulate matter.
The history of the group, and of wartime uses for detection by radio waves, traces back to about 1940, when Britain was besieged by the Germany Luftwaffe, the largest and most formidable air force in Europe.
The Gulf States and Turkey have formidable air power to enforce Arab League resolutions to protect civilians caught up in the war and as the first Gulf War U.S. leadership was decisive to encourage Arab states to take the front lines.
