Yes, probably sufficiently non viable that most operators will opt for 15 degrees only, unless the terrain is really tricky (PNG, Peru?). From NZ Part 121:
BANK ANGLE SPEED GRADIENT
15° to 19° V2 1 x Aeroplane flight manual 15° gradient loss
20° to 24° V2 + 5 knots 2 x Aeroplane flight manual 15° gradient loss
25° V2 + 19 knots 3 x Aeroplane flight manual 15° gradient loss
Last edited by Mach E Avelli; 31st Mar 2014 at 02:45.