Method and apparatus for onboard monitoring of aircraft takeoff

• US 4,773,015 A
• Filed: 02/06/1985
• Issued: 09/20/1988
• Est. Priority Date: 02/06/1985
• Status: Expired due to Term

• Current Assignee: Accutold A Joint Venture of TX
• Original Assignee: Accutold
• Inventors: Leland, James W., Kirkpatrick, James E.
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): Black, Thomas G.
• Application Number:
  US06/698,866
• Time in Patent Office: 1,322 Days
• Field of Search: 364/427, 364/561, 364/426, 73/178 T, 340/972, 244/183
• US Class Current: 701/15
• CPC Class Codes: G01C 23/005 Flight directors indicating arrangements specially adapted for rotary gyroscopes G01C19/32
• CPC Class Codes: G05D 1/0083 to help an aircraft pilot in the rolling phase

Abstract

An aircraft takeoff monitor having distance traveled sensors for measuring the distance traveled after the initiation of the takeoff roll. These sensors are interfaced with an onboard computer to provide the computer with information on the actual distance traveled by the aircraft since the takeoff run was initiated. The computer is programmable to receive predetermined input signals, including runway length, real-time inputs, and the initiation time, with the computer constantly generating a predicted ground distance that should be traveled since the initiation of the takeoff run. The computer is further programmed to compare the actual ground distance traveled to the predicted ground distance which should have been traveled and provide a display signal representative of this comparison on an onboard display instrument. Simultaneously the computer further continuously computes a predicted stopping distance for the aircraft at any time after the initiation of takeoff, adding the actual distance traveled to the predicted stopping distance, and subtracting these additive distances from the runway length, thereby generating a stopping distance display signal which is displayed on the onboard display instrument to indicate the distance the aircraft would predictably stop from the end of the runway.

Claims

1. An aircraft takeoff monitoring system comprising:

a first means for generating an actual ground distance traveled signal;

an onboard computer interfaced with said first means for processing predetermined and realtime input signals, including runway length, said computer continuously generating a predicted ground distance traveled signal;

said computer further programmed to continuously compare said actual ground distance traveled signal to said predicted ground distance traveled signal, said computer supplying a distance display signal representative of said comparison, said computer further still continuously computing a predicted stopping distance signal for said aircraft at any time, adding said actual ground distance traveled signal to said predicted stopping distance signal and subtracting said additive signals from said runway length input signal thereby generating a stopping display signal; and

an onboard display means responsive to said distance display signal and said stopping display signal for visually indicating a first difference between said actual ground distance traveled and said predicted ground distance traveled when said actual ground distance traveled is less than said predicted ground distance traveled, said display means further indicating a distance said aircraft would predictably stop from the end of said runway length.

2. The invention of claim 1 wherein said predetermined inputs comprise aircraft weight, altitude, runway gradient, ambient temperature, and wind velocity in direction of takeoff.

3. The invention of claim 1 wherein said predicted stopping distance signal is computed to allow for a predetermined reaction and delay time.

4. The invention of claim 1 wherein said first difference and said distance said aircraft would predictably stop from the end of said runway length are displayed in incremental linear units such that the rate at which said units are displayed is an indication of how rapidly said aircraft is falling behind in its takeoff and how rapidly said aircraft is running out of runway stopping distance.

5. The invention of claim 4 wherein said incremental linear units are displayed in a bar display calibrated to signify 50 feet for each increment, said bar display having a full scale of 20 increments or 1,000 feet.

6. The invention of claim 5 wherein after said full scale of either said first difference or said distance said aircraft would predictably stop from the end of said runway length is fully displayed, said full scale of said fully displayed scale flashes intermittently.

7. The invention of claim 6 wherein said first difference is displayed in a first color and said distance said aircraft would predictably stop from the end of said runway length is displayed in a second color.

8. An aircraft takeoff monitoring system comprising:

a first measuring device measuring aircraft actual ground distance traveled after an initiation time, said first measuring device for providing actual distance signals which are dependent upon said actual ground distance traveled after said initiation time;

an onboard computer interfaced with said first measuring device to receive said actual distance signals for processing predetermined and real-time input signals including runway length and said initiation time, said input signals and said time resulting in said computer continuously generating a predicted ground distance traveled after said initiation time signal;

said computer further programmed to continuously compare said actual ground distance signals to said predicted ground distance traveled after said initiation time signal, said computer supplying a distance display signal representative of said comparison, said computer further still continuously computing a predicted stopping distance signal for said aircraft at any time after said initiation time, adding said actual ground distance signals to said predicted stopping distance signal and subtracting said additive signals from said runway length input signal thereby generating a stopping display signal; and

an onboard display means responsive to said distance display signal and said stopping display signal for visually indicating a first difference between said actual ground distance traveled and said predicted ground distance traveled when said actual ground distance traveled is less than said predicted ground distance traveled, said display means further indicating a distance said aircraft would predictably stop from the end of said runway length.

9. A method for monitoring an aircraft takeoff comprising the steps of:

determining said aircraft'"'"'s actual ground distance traveled after an initiation time;

computing from predetermined and real-time inputs a predicted ground distance traveled by said aircraft after said initiation time;

computing a predicted distance required to stop said aircraft after said initiation time;

continuously comparing said predicted ground distance to said actual ground distance;

continuously adding said predicted stopping distance to said actual ground distance and subtracting said additive distance from a predetermined runway length input;

continuously displaying, whenever said actual ground distance traveled is less than said predicted ground distance, the difference between said actual ground distance and said predicted ground distance such that the rate of said displaying indicates how rapidly said aircraft is falling behind in its takeoff; and

continuously displaying the distance said aircraft would predictably stop from the end of said runway length such that the rate of such displaying indicates how rapidly said aircraft is running out of runway stopping distance.

10. The method of claim 9 wherein said step for determining said aircraft'"'"'s actual ground distance traveled after initiation time is accomplished by means of an accelerometer.

11. The method of claim 9 wherein said step for determining said aircraft'"'"'s actual ground distance traveled after initiation time is accomplished by means of a wheel rotation sensor.

12. The method of claim 9 wherein said step for determining said aircraft'"'"'s actual ground distance traveled after initiation time is accomplished by means of a radar sensing device.