  This paper is an addition to an article previously published by three of the
authors that addresses the control of convertible fixed-wing aircraft with
vectorized thrust. The control solution here developed extends the one
presented in the former paper by complementing it with a strategy for the
hovering flight and a control policy to handle the transition phase between low
and high airspeed. An estimator of the air velocity required in all flight
phases is also proposed. Realistic simulation results on a tri-tilt rotor
Unmanned Aerial Vehicle (UAV) illustrate and assess the methodology.
