Spectrum intended to improve on the RX 550 .
Spectrum introduced the Beaver RX 650 in 1991 , intending to place it in the Advanced Ultra-light Aeroplane category ( AULA ) in Canada .
Intending to improve on the RX 550 , Spectrum introduced the Beaver RX 650 in 1991 , intending to place it in the Advanced Ultra-light Aeroplane category ( AULA ) in Canada .