Some Hybrid designs, such as the Lockheed Martin LMZ1M, use a flattened or multi-lobed hull to increase the aerodynamic lift obtainable. The aerodynamic approach is similar to that of a lifting body aircraft, although the airspeeds involved are much lower. Attainable dynamic-lift-to-drag ratios are significantly below those of efficient fixed wings, in part because induced drag increases with decreasing aspect ratio. As a result, the lift comes at a higher drag penalty than when using wings. On the other hand, compared to a helicopter, the dynastat has better fuel efficiency within a given speed range.