GB743050A - Improvements in or relating to thrust-spoiling devices for jet propulsion units - Google Patents

Abstract

743,050. Propelling aircraft. SOC. NATIONALE D' ETUDE ET DE CONSTRUCTION DE MOTEURS D'AVIATION. Dec. 10, 1953 [Dec. 12, 1952], No. 34440/53. Class 4. [Also in Group XXVI] A jet propulsion unit thrust spoiler comprises laterally extending passage means through the casing surrounding the exhaust pipe, to provide a passage for gas flow to atmosphere at a substantial angle to the pipe axis, the passage being upstream of the nozzle terminating the jet pipe, and auxiliary nozzle means controllably supplied with pressure fluid, disposed at the periphery of the pipe and opening thereinto upstream of the passage and adapted to form a fluid screen about the main gas flow past the passage. In Fig. 2, the main jet flows from a turbine 2 out through a nozzle 3. The channels for the deflected jet comprise a series of curved blades 11. When the jet is not to be deflected, a valve 21 in a conduit 20 is opened, permitting air to flow from the outlet of the compressor unit through an annular slot 18, the resulting flow-ending to restrict the main flow and prevent it from entering the blades 11. To deflect the jet, valve 21 is shut, and a streamlined obstacle 25 may be turned to the position shown dotted to assist deflection of the jet into the blades 11. Orifices 13 are provided to supply air to fill in the low pressure wake zone formed downstream of slot 18 when valve 21 is open, reducing turbulence. The cooling circuit of the engine provides a suitable source, alternatively air inlets 22 may be provided in the cowling 4. Preferably two diametricallyopposite passages are provided, each with blades 11, and instead of a solid obstacle 25, jets of air may be blown radially inwards from nozzles 14, 15 (Fig. 2) tending to restrict the jet and fan it out in the diametral plane containing the blades 11. Specifications 691,302 and 696,088 are referred to.