What, if any, is the FOD damage possibility that faces a fuselage mounted engine (e.g. MD-88, Lear 45, CRJ series) in terms of operating on a less than optimal runway surface? I know that on 737 Classics, there were kits available specifically for dealing with this kind of situation, but would something of the same type need to be developed to operate something like an MD-88 on an unimproved surface, baring any other modifications that would have to occur to the airframe? I would think that with the engines being higher on the fuselage, the risks of FOD damage from items like gravel would be much less. The only problem that seems to spring to mind is the placement of the wheels on fuselage-engined aircraft tend to be down in front of the engines and that they could kick up some sort of debris.