Patent ID: 8915473

Claim:
An apparatus comprising: a hold-down mechanism for a steerable spacecraft appendage, said appendage being coupled to a spacecraft structure with a positioning mechanism; the hold-down mechanism comprising: a frame, hingedly attached, at an inboard portion, to the spacecraft structure, and detachably engaged, at an outboard portion, to a structural element of the appendage; and a deployment spring, said deployment spring configured such that, upon release of the appendage, the deployment spring drives a rotation of the frame about a hinge axis, thereby causing the hold-down mechanism to retract from the appendage; wherein: the frame is detachably engaged to the structural element of the appendage by a cup and cone arrangement, the cup and cone arrangement being characterized by a longitudinal axis and a separation interface, the longitudinal axis being perpendicular to a plane passing through the separation interface and the hinge axis, and the hold-down mechanism is configured to: support, when in a hold-down mode, the appendage at a first position substantially fixed with respect to the spacecraft, and isolate the positioning mechanism from loads imparted by the spacecraft appendage as a result of launch or other dynamic environment such that the loads are reacted by the hold-down mechanism and not the positioning mechanism; release, upon receipt of a signal, the appendage, thereby enabling the positioning mechanism to steer the spacecraft appendage; and retract from the appendage without regard to whether the appendage remains substantially in the first position.