They use the same weights on the 146 to Scs as the helicopters- actual weights ..... otherwise I hear they have to use a std wt of 98Kg without hand baggage. If they are forced to land downhill with lack of headwing component headwind then they are severely restricted for landing. lack of wind is surprisingly common in Summer and they often need 3 146's to carry the 6 S92 loads. That is probably why the need three flying and one on standby. Additionally there now seems to further additional restrictons when the runway is wet. However take offs are unrestricted....The Jets have the opposite problem to the turboprops, who seem Ok landing, but restricted taking off