Abstract: A rotary blade is provided that includes a root, an airfoil, and a tip insert. The airfoil is attached to the root, and has a suction side surface, a pressure side surface, a leading edge, a trailing edge, a tip, and a slot disposed within the tip. The slot extends in a chordwise direction between the leading edge and trailing edge. The tip insert has a base end and a rub end. The base end of the tip insert is disposed within the slot. The rub end of the tip insert extends radially outward from the airfoil tip.

Abstract: A rotary blade is provided that includes a root, an airfoil, and a tip insert. The airfoil is attached to the root, and has a suction side surface, a pressure side surface, a leading edge, a trailing edge, a tip, and a slot disposed within the tip. The slot extends in a chordwise direction between the leading edge and trailing edge. The tip insert has a base end and a rub end. The base end of the tip insert is disposed within the slot. The rub end of the tip insert extends radially outward from the airfoil tip.

Abstract: For the purpose on monitoring the condition in the interior of a closed metallic honeycomb panel, an optical fiber is embedded therein. An optical connector, secured within a groove has one end exposed to a source of external light, while the optical fibers are connected to the other end of the connector. In the example disclosed, the end of the optical fiber within the structure is coated with a sensor material subject to the same condition (corrosion) taking place within the structure. The reflectivity of the coating from a source of light applied through an optical connector is a measure of the condition.

Abstract: The disclosed system comprises a receiver that is inductively coupled to one or more passive transmitters by means of a receiving inductor. The receiver comprises a sweep signal source which is coupled equally to the receiving inductor and a reference inductor. The receiving inductor is coupled to a passive transmitter which includes an L-R-C circuit comprised of a transmitting inductor, a temperature-dependent capacitor, and a resistor that may be variable or fixed, depending upon the application. As the sweep signal source passes through the resonant frequency of the passive transmitter, the passive transmitter forms a low impedance load magnetically coupled to the receiving inductor by means of the near or induction electromagnetic field produced by the inductor. Changes in the resonant frequency are used to determine temperature variation.