GAS TURBINE ENGINES

• US 3,820,719 A
• Filed: 04/30/1973
• Issued: 06/28/1974
• Est. Priority Date: 05/09/1972
• Status: Expired due to Term

• Current Assignee: Clark K
• Original Assignee: Clark K
• Inventors: CLARK K
• Application Number:
  US05/355,425
• Time in Patent Office: 424 Days
• US Class Current: 239/265.31
• CPC Class Codes: F02K 1/09 by axially moving an external member, e.g. a shroud F02K1/12 takes precedence
• CPC Class Codes: F02K 1/66 using reversing fan blades

Abstract

A fan type gas turbine engine for use in an aircraft, the engine having a fan cowl comprising at least two annular parts, one part being axially separable from the remainder of the fan cowl to provide an annular opening giving additional nozzle area during take-off conditions and being shaped to promote attachment of the extra nozzle flow to its outer surface; and, if the fan is a variable pitch fan, the additional nozzle area can serve as additional intake area for the fan during operation in the reverse pitch mode.

Claims

1. A nozzle for a ducted fan gas turbine engine having fan cowl means defining the nozzle area, means for relatively axially separating an upstream portion and a downstream portion of the fan cowl means to define an opening therebetween, means for directing a portion of the nozzle flow through said opening and for promoting attachment of the nozzle flow to the outer surface of the said dowNstream portion.

2. A nozzle for a gas turbine engine according to claim 1 and wherein the said ducted fan engine comprises a variable pitch fan engine.

3. A nozzle for a gas turbine engine according to claim 2 and wherein the said opening in the fan cowl means defines intake means for reversed thrust operation of the fan.

4. A nozzle for a gas turbine engine according to claim 3 wherein the size of said opening when operating as a nozzle differs from the size of said opening when defining intake means for reversed thrust operation of the fan.

5. A nozzle according to claim 1 and comprising guide rail means for supporting one of said upstream or downstream portions for movement relative to the other of said portions.

6. A nozzle according to claim 1 and comprising recirculating ball jack means for separating the said upstream and downstream portions.

7. A nozzle according to claim 1 and including sealing means between the said axially relatively separable portions.

8. A nozzle for a variable pitch fan engine comprising a fan cowl which together with a core engine defines the nozzle area, the fan cowl having an upstream portion and first and second downstream portions characterised in that there is provided means for relatively axially separating the second downstream portion from the upstream and first downstream portion to provide additional nozzle area and means for separating the first and second downstream portions from the upstream portion to define an opening, the opening defining intake means for reversed thrust operation of the fan.