American helicopters routinely fly at tree-top level, bobbing and weaving on their way to their destination.
In 1961, Douglas Point set up an information office and a Bailey bridge at tree-top level providing a view of the site.
Accompanied by a second helicopter that carried aides, he flew off toward Split at tree-top level.
All three were experienced pilots and chased Oesau from 28,000 feet to tree-top level.
Sandinista helicopters flying at tree-top level began to shuttle troops to landing zones close to the border.
By the time he regained his breath, he was well above tree-top level.
Flies at tree-top level until it chooses to descend if there is strong morning sunlight.
When the sled took off, due south, it cruised just above tree-top level.
There were only a few missiles of modest size, but they approached at tree-top level from the sides.
The beecraft dropped low and approached the aerodromos just above tree-top level.