Entry, display and use of data employed to overcome aircraft control problems due to wind shear
OwnerJohn H. Blissinventor
Life of this patent
Estimating the term…
Abstract
A system of airplane instrumentation utilizing devices and procedures for dealing with wind shear on the final approach to a landing. The system is designed for use in a like manner on all approaches for landing to assure that a safe, stable speed be used during all landing approaches, and that the Pilot be apprised of the conditions his airplane is flying through at all times during the approach. The primary aim is to provide instrumentation which will aid the Pilot in achieving safe approach criteria, give him information on which to base his judgment, and eliminate accidents on the final approach due to wind shear.
Claims33
In the method of controlling the power to be applied to an aircraft engine during a final approach, whether wind shear conditions exist or not, and including the steps:
- (a) monitoring deviation of actual airspeed from a target airspeed on the approach, and deviation of actual groundspeed from a target approach groundspeed on the approach, and
- (b) employing such deviations in such a manner so that the approach speed is controlled by whichever of the actual speeds is lower compared to its associated target speed, and using said lower actual speed to control power to maintain a stabilized aircraft speed condition during the final approach, the improvement comprising:
- (c) utilizing air temperature and pressure data to modify the value of target indicated airspeed thereby to derive a true airspeed value for use as a zero wind groundspeed marker value,
- (d) displaying said value, and
- (e) modifying said value as a function of an automatically or manually programmed surface wind velocity along course component to derive an uncompensated value of said target approach groundspeed, and
- (f) in the case of a manually programmed surface wind velocity value, correcting said uncompensated value by selecting one of a group of possible percentages of wind component to derive a compensated target approach groundspeed.
In the method of controlling the power to be applied to an aircraft engine during a final approach, whether wind shear conditions exist or not, and including the steps:
- (a) monitoring deviation of actual airspeed from a target airspeed on the approach, and deviation of actual groundspeed from a target approach groundspeed on the approach, and
- (b) employing such deviations in such manner so that the approach speed is controlled by whichever of the actual speeds is lower compared to its associated target speed, and using said lower actual speed to control power to maintain a stabilized aircraft speed condition during the final approach,
- the improvement comprising:
- (c) utilizing air temperature and pressure data to modify the value of target airspeed thereby to derive a true airspeed or zero wind marker value,
- (d) displaying said value, and
- (e) said displaying including providing a ground speed scale and a zero wind marker associated with said scale to indicate on said scale,
- (f) providing a GS target index associated with said scale to indicate said target approach groundspeed on said scale,
- (g) and providing wind velocity component correction selectors, and adjusting the position of the GS target index as a function of selecting a correction selector that corresponds to a chosen percentage wind velocity component correction to be made subsequent to earlier positioning of the GS target index.
In the method of controlling the power to be applied to an aircraft engine during a final approach, whether wind shear conditions exist or not, and including the steps:
- (a) monitoring deviation of actual airspeed from a target airspeed on the approach, and deviation of actual groundspeed from a target approach groundspeed on the approach, and
- (b) employing such deviations in such a manner so that the approach speed is controlled by whichever of the actual speeds is lower compared to its associated target speed, and using said lower actual speed to control power to maintain a stabilized aircraft speed condition during the final approach,
- the improvement comprising
- (c) providing a ground speed scale, a GS marker associated with said scale to indicate said actual groundspeed on the scale, and a GS target index associated with said scale to indicate said target approach groundspeed on said scale, and
- (d) providing wind velocity component correction selectors, and adjusting the position of the GS index target as a function of choosing a correction selector that corresponds to a chosen percentage wind velocity component correction to be made subsequent to earlier positioning of the GS target index.
In apparatus useful in determining power to be applied to an aircraft engine during the final approach to a landing, the combination comprising
- (a) first means for monitoring deviations of actual aircraft airspeed from a target approach indicated airspeed, and deviations of actual aircraft groundspeed from a target approach groundspeed,
- (b) second means coupled to said first means for providing an indication from which engine power application may be controlled, and
- (c) computer means responsive to said target approach indicated airspeed value and to air temperature and pressure conditions to compute a value of true airspeed, or zero wind groundspeed, and responsive to said value and to a surface wind component to derive said approach target groundspeed, there being means providing a group of selectors corresponding to different percentages of wind component and adapted to be selected to modify said approach target groundspeed.
In the method of controlling an aircraft's speed on the final approach to a landing by controlling the power to be applied by its engines, and with the use of a groundspeed value equal to that which will obtain when approach the runway threshold on that particular approach with the conditions existing in the landing area regarding altitude, temperature, and wind conditions, the improvement consisting of the method including:
- (a) converting a normal approach Indicated Airspeed (IAS) target value to a related True Airspeed (TAS) value and using said related TAS value as a zero wind reference or marker value on a groundspeed indicator, said conversion including modifying a Central Air Data Computer (CADC) or using data from said CADC to perform such conversion,
- (b) employing computer means to resolve an along course wind component using said related TAS value, said employment including applying surface wind direction and velocity and inbound course information, and
- (c) if the surface wind information is not automatically continuously programmed, modifying said surface wind application with a percentage application in such manner that a percentage of wind application may be selected from a group of possible percentage values late during the final approach when insufficient time remains to reset a new surface wind direction and velocity into the computer as may be more recently reported by a control tower, and
- (d) applying said surface wind along course component value to said zero wind marker or related TAS value to establish a GS target index value of expected GS when approaching the runway threshold, and displaying same on a groundspeed indicator as an additional speed criteria for use all during the final approach, and
- (e) using said GS indicator, with said zero wind marker or reference along with said GS target value relative to the display of actual GS, such GS target value used to establish an additional speed criteria for use all during the final approach so that the aircraft speed may at all times be maintained equal to or in excess of one of the following parameters:
- GS equal to or in excess of the GS target value or IAS equal to or in excess of the IAS target value.
In apparatus useful in controlling an aircraft's airspeed on the final approach to a landing by controlling the power to be applied by it's engine, such speed value designed to be safe regarding possible windshear conditions, the improvement including:
- (a) first computer means responsive to an airspeed target value and to aircraft altitude and air temperature conditions to compute a true airspeed value of said airspeed target value to program a zero wind marker value for display on a groundspeed indicator scale,
- (b) second computer means responsive to said zero wind marker value and to an along-course surface wind component value to derive a groundspeed target index value for display on said groundspeed indicator scale,
- (c) third means responsive to said airspeed compared to said airspeed target value, and responsive to GS compared to said groundspeed target index value for providing a speed criteria from which engine power may be controlled to maintain the lower of the two speed values defined as airspeed relative to said airspeed target index, or groundspeed relative to said groundspeed target index, and
- (d) fourth means coupled to said third means for providing an indication from which engine power application may be controlled, including a fast/slow indicator, and including a signal means from which an automatic throttle device may be programmed.
Dependencies are inferred from the claim text.