Suspension structure for suspending a turboprop having two unducted propellers from a structural element of an aircraft with rigid fastening of the air intake structure
A suspension structure for suspending a turboprop including two unducted propellers from a structural element of an aircraft, the structure including a suspension frame for fastening to a structural element of the aircraft and including a main beam extending parallel to a longitudinal axis of the turboprop, the suspension frame being fastened to an air intake structure of the turboprop by an attachment frame.
1. A suspension structure for suspending a turboprop including two unducted propellers from a structural element of an aircraft via an attachment pylon, the structure comprising:
a suspension frame for fastening to an extremity of the attachment pylon of the aircraft and including a main beam extending parallel to a longitudinal axis of the turboprop; and
an attachment frame which rigidly connects the suspension frame to an air intake structure of the turboprop,
wherein the attachment frame includes two longitudinal arms connected together by a front frame rigidly fastened to the air intake structure of the turboprop with a degree of freedom for adjustment in a plane that is transverse relative to the longitudinal axis of the turboprop, and by a rear frame fitted into the suspension frame, the front frame, the rear frame, and the longitudinal arms connected to each other forming a through structure.
2. A structure according to claim 1 , wherein the suspension frame further includes two lateral beams fastened to the main beam such that the suspension frame presents a V-shaped structure.
3. A structure according to claim 2 , wherein each of the two lateral beams includes at its free end opposite to the attachment frame a fastening to rigidly fasten the suspension frame.
4. A structure according to claim 1 , wherein the attachment frame is fastened to the air intake structure of the turboprop by bolt fasteners passing through holes of oblong shape formed in the attachment frame to impart the degree of freedom for adjustment in a plane that is transverse relative to the longitudinal axis of the turboprop to the connection between the attachment frame and the air intake structure.
5. A structure according to claim 1 , wherein the attachment frame is configured to allow passing of pipework of the turboprop to the attachment pylon.
6. A structure according to claim 1 , wherein a connection between the attachment frame and the air intake structure of the turboprop includes at least one sliding pivot connection enabling the air intake structure to be opened.
7. A structure according to claim 6 , wherein the air intake structure of the turboprop includes two lugs, each co-operating with a pin secured to the attachment frame to form two sliding pivot connections.
8. A structure according to claim 6 , further comprising a closure catch between the air intake structure of the turboprop and a stationary fan cover of the turboprop to avoid untimely opening of the air intake structure.
9. A structure according to claim 8 , wherein the closure catch and the sliding pivot connection are diametrically opposite.
10. A structure according to claim 1 , wherein the suspension frame further includes two thrust take-up rods for connecting a main beam to an engine casing, and a downstream suspension rod and an upstream suspension rod for connecting the two ends of the suspension frame to the engine casing.