The nacelles can rotate past vertical to 97.5 for rearward flight.
They weren't supposed to do that until the transport went on vertical flight.
The note of the engines changed as the transport went to vertical flight.
The wave should be very steep to encourage a more vertical flight as you take off.
Starfuries are usually in vertical flight only clicks after leaving the water.
The earliest references for vertical flight have come from China.
As scientific knowledge increased and became more accepted, men continued to pursue the idea of vertical flight.
On 23 July 1958, the aircraft made its first full transition from vertical flight to horizontal flight.
Proposed Standard: vertical flight only, to a maximum of 20 feet above the ground.
Sikorsky also continued his earlier work on vertical flight.