According to JRCALC, Clinical Practice Guidelines on the Dosage and Administration of Morphine Sulphate for adults the maximum dosage is 20mg?? It might be that different regions have different protocols but certainly where I work the maximum dosage is 20mg, as for the rest of the skills to RSI I take the point that the close confines of the back of the helicopter is not the best place to do this but then again what is easy to do in the back of a helicopter? At least if the option exists and this does not delay the immediate and rapid transportation of the patient to definitive care then in some cases to RSI a patient on scene will be the best option.