Abstract: Side plate members have a connecting clevis at one end and portions which encircle and clear the hub of a flanged hub member at the other end. Shear pins mount in holes provided in the flange and side plates such that relative motion between the hub and clevis is prohibited. The side plate members are flexible along the axis of the pins to prevent galling or reseizing caused by the rough edges of fractured pins.

Abstract: Upon aircraft landing approach, flare path command signals of altitude, vertical velocity and vertical acceleration are generated as functions of aircraft position and velocity with respect to the ground. The command signals are compared with corresponding actual values to generate error signals which are used to control the flight path.

Abstract: Aircraft altitude, ground velocity, and altitude rate signals are input to a computer which, using a unique control law, generates a pitch control surface command signal suitable for guiding an aircraft on its flare path to a specified runway touchdown point despite varying wind conditions.

Abstract: An aircraft guidance system operable during both takeoff and go-around maneuvers allows safe operation even under adverse wind shear conditions. Initially the system controls vertical speed to achieve an acceptable, minimum climb rate regardless of airspeed loss. Should excess thrust exist such that the acceptable minimum climb rate is exceeded, increased vertical speed and airspeed are commanded. When the climb rate significantly exceeds the acceptable minimum, airspeed is controlled to a specified value. Should the aircraft ever approach the "stick shaker" condition, an override command limits aircraft angle of attack.

Abstract: A self contained switch assembly of the type indicating the status of a moveable mechanical structure, such as a door being in proper position for latching, includes a proximity sensor mounted to a base plate. Also mounted to the base plate is a plunger mechanism which carries a target plate. Upon the striker surface of the plunger engaging an external object, the target plate moves into proximity with the sensor, thereby producing a status signal.

Abstract: A system for providing an optimum lift demand signal for aircraft maneuvers such as "go-around" includes a computer for generating a reference angle of attack signal which is functionally related to the aircraft's vertical velocity. The reference signal is compared with a signal corresponding to the aircraft's actual angle of attack, thereby producing an error signal. The error signal is utilized as a control to the aircraft's dynamics for optimizing the aircraft's climb-out performance.

Abstract: The transient limiter suppresses high voltage transients induced on an alternating current (AC) carrying power line. A Zener diode string breaks down for voltages on the line which exceed the peak AC voltage. The breakdown current is directly connected to the gate terminals of a pair of silicon controlled rectifiers (SCR's). Each rectifier is series connected to a voltage responsive resistor with the combination being connected across the power line terminals. Upon breakdown of the Zener diode string one of the SCR's and its associated voltage responsive resistor switch to a low impedance state, thereby limiting the peak voltage on the power line.

Abstract: A pivotal crank is positioned with respect to the output cam of a torque limiter such that upon torque limiter operation the resulting translation of the cam pivots the crank. Attached to the crank is a flag arm which is normally retained by a spring clip. Pivotal motion of the crank causes disengagement of the flag arm from the spring clip thereby indicating torque limiter operation. The flag arm remains in the disengaged position, despite subsequent absence of limiter operation, until it is manually reset.

Abstract: Upon landing approach to a runway, glideslope and altitude information is processed to produce an indication of ground distance to the touchdown point. Actual aircraft position is then determined by integrating the aircraft's ground speed. A display of distance from the beginning and end of the runway is provided. An alert is produced if the aircraft approaches the end of the runway at excessive speed. Further, the system may be coupled to the aircraft's autobrake system to automatically control the rate of deceleration.

Abstract: Aircraft navigation testing apparatus includes circuitry which produces digital signals on an output bus corresponding to a desired simulation of aircraft glideslope, localizer and very high frequency, omnidirectional (VOR) positions. Localizer and glideslope circuitry respond to the signal on the bus to produce the desired final value signal at the dictated rate. VOR circuitry responds by activating selected switches in a switchbank, thereby programing a conventional VOR generator to produce the VOR signal at the desired rate.

Abstract: High voltage transients, such as from lightning strikes, on an AC carrying power line are suppressed by unique protection circuitry. Voltage on the line is sensed and should it exceed a predetermined reference level an appropriate one of two silicon controlled rectifiers is activated. The rectifiers are connected in series with a voltage dependant resistor and the resultant network is coupled between the terminals of the power line. The network is effectively an open circuit under exposure to the periodic waveform normally existing on the power line. Upon occurrence of a high voltage transient, the combination of one of the rectifiers and the voltage dependant resistor switches to a low impedance state, thereby accomplishing suppression.

Abstract: An improved fluid flow control valve of the type wherein a spool is slidable within a sleeve cavity provided in the valve body. Primary fluid passageways through the body access the sleeve cavity at main orifices which form metering surfaces with lands on the spool. The improvement comprises secondary fluid passageways which carry parallel flow with the primary passageways. The secondary passageways access the sleeve cavity at sacrificial orifices which form sacrificial metering surfaces with the spool lands. The sacrificial metering surfaces carry all of the flow through the valve at the valve neutral position thus reducing flow erosion at the main metering surfaces. Valve leakage is limited to a small value determined by the total flow capacity of the secondary passages.

Abstract: Multiple redundant sensor signals are processed through an equalizing and selecting network which outputs the midvalue signal and eliminates all null offsets occurring among signals. Errors due to drift in a signal are minimized by bounding the output to the limits of the remaining redundant signals. Faults of both a high and low frequency nature are detected resulting in the isolation of the appropriate signal channel.

Abstract: A hose clamp includes a coupler body and spring wire. The coupler is substantially triangular in cross section, having a pair of passageway interconnecting two surfaces. The wire, having a head on one end, is routed through one passageway, around the hose and then through the remaining passageway being secured by a thrust washer to the opposite coupler surface.

Abstract: The air supply to an aircraft is provided by air conditioning apparatus operable in a powered bootstrap simple cycle or bootstrap cycle mode. Logic circuitry selects and activates the system to that mode best suited to existing conditions.

Abstract: A material under test is scanned by transmit and receive ultrasonic transducers, thus generating data representative of the structural integrity of the material at precise locations thereof. The data is stored in memory for recall to excite a graphics display of the material. A user may define any boundary shape within the display and thereby cause a computer to recall and statistically process only those data points within the boundary.

Abstract: The signal generator produces an output comprised of a periodic signal and a precision amplitude pulse. A periodic waveform source is fed to the center tap of a transformer. The instantaneous amplitude of the waveform is sensed and, when it reaches a predetermined level, one free end of the transformer is grounded thereby producing a predetermined amplitude pulse, superimposed on the periodic waveform, at the remaining free end.

Abstract: Signals carried over a multiplexed transmission medium between first and second stations suffer transmission losses such that the signal one station generates has a substantially greater magnitude than the signal it receives from the other station. A differential amplifier is utilized to extract and amplify the weaker signal thereby establishing signal balance. Following the differential amplifier is an automatic gain control stage which includes novel sample and hold and activity checker circuitry. The activity checker responds to the frequency of input signals to either allow variable gain control action or, when the frequency is representative of noise, to hold the gain control at its instantaneous value prior to the onset of noise.

Abstract: Digitally encoded data is carried over a first channel between a base station and a plurality of mobiles with the mobiles sharing a second channel for transmission to the base on a contention basis. Proper decoding of the data requires clock syncing at the receiver site.To hasten clock recovery lock time at the base station and improve system throughput, each mobile includes apparatus for monitoring transmissions by the base station and deriving a transmit clock base for the mobile's transmitter therefrom such that subsequent transmissions by the mobiles are all substantially in synchronization.