Abstract: Systems and methods for the manufacture and use of artificial ice shapes for aircraft certification, including methods of manufacturing artificial ice shapes, artificial ice component systems for attachment to aircraft, methods of flight testing aircraft having artificial ice sections attached thereto, and artificial ice testing systems.

Abstract: A tunable mass-damping apparatus may include a housing having an interior surface, an interior volume containing a fluid, and an axis. The housing may be configured to be coupled to a wind tunnel model. The apparatus may further include a mass configured to move back and forth in the interior volume along the axis. The mass may be configured to make an airtight seal with the interior surface of the housing, thereby dividing the interior volume into an upper chamber and a lower chamber. The apparatus may include a passage fluidly connecting the upper chamber and the lower chamber and a spring configured to exert a position-dependent force upon the mass. The spring may be characterized by a variable spring constant chosen based on a variable natural frequency of a support structure of the wind tunnel model. The variable spring constant may be established with a nickel-titanium alloy spring heated to at least one calibrated temperature that corresponds to a predetermined spring constant.

Abstract: A tunable mass-damping apparatus may include a housing having an interior surface, an interior volume containing a fluid, and an axis. The housing may be configured to be coupled to a wind tunnel model. The apparatus may further include a mass configured to move back and forth in the interior volume along the axis. The mass may be configured to make an airtight seal with the interior surface of the housing, thereby dividing the interior volume into an upper chamber and a lower chamber. The apparatus may include a passage fluidly connecting the upper chamber and the lower chamber and a spring configured to exert a position-dependent force upon the mass. The spring may be characterized by a variable spring constant chosen based on a variable natural frequency of a support structure of the wind tunnel model. The variable spring constant may be established with a nickel-titanium alloy spring heated to at least one calibrated temperature that corresponds to a predetermined spring constant.

Abstract: Systems and methods for the manufacture and use of artificial ice shapes for aircraft certification, including methods of manufacturing artificial ice shapes, artificial ice component systems for attachment to aircraft, methods of flight testing aircraft having artificial ice sections attached thereto, and artificial ice testing systems.

Abstract: Systems and methods for the manufacture and use of artificial ice shapes for aircraft certification, including methods of manufacturing artificial ice shapes, artificial ice component systems for attachment to aircraft, methods of flight testing aircraft having artificial ice sections attached thereto, and artificial ice testing systems.

Abstract: Systems and methods for the manufacture and use of artificial ice shapes for aircraft certification, including methods of manufacturing artificial ice shapes, artificial ice component systems for attachment to aircraft, methods of flight testing aircraft having artificial ice sections attached thereto, and artificial ice testing systems.

Abstract: A method and apparatus for locking an externally threaded member in place. An apparatus comprises a number of internally threaded members and a shape memory element associated with the number of internally threaded members. The number of internally threaded members is configured to engage the externally threaded member. Changing a baseline shape of the shape memory element to a modified shape either prevents or allows movement of the number of internally threaded members relative to the externally threaded member.

Abstract: A method and apparatus for locking an externally threaded member in place. An apparatus comprises a number of internally threaded members and a shape memory element associated with the number of internally threaded members. The number of internally threaded members is configured to engage the externally threaded member. Changing a baseline shape of the shape memory element to a modified shape either prevents or allows movement of the number of internally threaded members relative to the externally threaded member.