Abstract:
The net vertical thrust available to an aircraft for vertical take-off and landing falls off with proximity to the ground. Measurements have been made of this thrust loss as a function of wing height above the ground, on plane circular and delta wings, and on a 1/6th scale model of the Short SC1 aircraft. At normal undercarriage height, the Short SC1 would lose nearly 20% of its vertical thrust, but a scheme has been developed to reduce the thrust loss to negligible proportions.