Hidden thrust reverser blocker door link arm fitting

A nacelle for a gas turbine engine comprising:

• an inner fixed structure (IFS) comprising a proximal layer and a distal layer;
• a link arm having a first end and a second end, wherein a second aperture is disposed in the link arm at the first end, the link arm configured to rotate about the second aperture;
• and
• a fitting arrangement for the link arm comprising:
• a pivot extending through the second aperture;
• a retaining member having a first end and a second end and defining a first aperture and a cavity,
• wherein the pivot extends at least partially into the first aperture and at least a portion of the first end of the link arm is located within the cavity,
• wherein the retaining member comprises an attachment aperture located at the first end of the retaining member and a lip extending from the retaining member at the second end of the retaining member, the attachment aperture configured to receive a fastener, the fastener configured to receive a nut to secure the retaining member to the IFS, and the lip located under the distal layer of the IFS, and
• wherein the retaining member is disposed at least one of radially inward of the distal layer or flush with the distal layer, wherein the nut is accessible from a bypass flow path;
• a housing configured to encase a portion of the retaining member, the housing being coupled to the IFS and comprising a first portion radially inward of the retaining member and a second portion configured to cover the lip, the fastener extending from the housing.

A method of installing a linkage system to a nacelle comprising:

• placing a pivot at least partially into a first aperture disposed in a retaining member;
• positioning the first aperture and a second aperture disposed in a thrust reverser link arm in concentric alignment;
• placing the pivot at least partially into the second aperture of the thrust reverser link arm;
• placing a lip underneath a distal layer of an inner fixed structure (IFS), the lip extending from the retaining member, the retaining member defining at least a portion of the first aperture and defining at least a portion of a cavity, at least a portion of the link arm being located within the cavity;
• placing a fastening aperture disposed in the retaining member to surround a fastener, the fastener being coupled to the IFS;
• and fastening the retaining member to the fastener via a nut, wherein the method is performed from a bypass flow path of the nacelle and the nut is accessible from the bypass flow path of the nacelle;
• a housing configured to encase a portion of the retaining member, the housing being coupled to the IFS and comprising a first portion radially inward of the retaining member and a second portion configured to cover the lip, the fastener extending from the housing.