Medium Speed V/STOL Propulsion Installation Losses - Comparison of Prediction and Model Test Data

A medium speed V/STOL aircraft has been configured using a tandem fan propulsion system concept. Each tandem fan nacelle has two unique inlets and nozzles. Isolated and combined inlet tests were conducted at NASA Lewis. Compatible inlet operation was established with beneficial interaction occurring between the inlets resulting in improved total pressure recovery. Isolated nozzle tests have also been conducted by NASA Lewis. The front nozzle test was preceeded by parametric nozzle tests at Vought to establish the baseline configuration. Results from both static and low speed tests have consistently shown better than predicted performance for both inlets and nozzles.