From the outside, the 8,000-square-foot building is a play of curves against planes.
Concentrating on flowers, he played off their intricate outlines against flat planes of color.
In the last five years alone, terrorist attacks against planes of a half-dozen countries have killed 1,030 people.
Other rifles could also be used against planes on the ground, Mr. Barrett said.
The 20mm anti-aircraft guns were removed without replacement shortly after the war because they had been ineffective against Japanese planes.
On 3 September 1917, he was wounded in action while in combat against several German planes.
They are simplified silhouettes against large planes of color, silent and calm.
The Perry frigates have a smaller 76-millimeter gun, more useful against low planes and small ships.
Safety board officials said it was fine that computerized protection against uncontrolled planes would soon be provided at higher altitudes between major airports.
Anti-aircraft guns are effective against planes when used in large numbers.