Most low-cost carriers operate aircraft configured with a single passenger class, and most operate just a single aircraft type, so cabin and ground crew will only have to be trained to work on one type of aircraft, however some low-cost carriers choose to operate more than one type and configure their aircraft with more than one passenger class. This is also beneficial from a maintenance standpoint as spare parts and mechanics will only be dedicated to one type of aircraft. These airlines tend to operate short-haul flights that suit the range of narrow-body (single aisle) planes. As of lately however there is also a rise in demand for long range low-cost flights and the availability of next generation planes that make long haul routes more feasible for LCCs.