The T21b at Sharjah came from Aden and was known as '404' but i don't think it was marked as such. It had white fuselage, yellow wings, rudder, tailplane & elevator. We knew the club as 'Gulf Services Gliding Club' but i see that my membership card has 'R.A.F. Sharjah' at the top and simply 'Gliding club' at the bottom.