Method of determining status of aircraft landing gear

• US 6,293,141 B1
• Filed: 05/22/2000
• Issued: 09/25/2001
• Est. Priority Date: 04/15/1997
• Status: Expired due to Term

• Current Assignee: Hydro-Aire, Inc. (Crane Company)
• Original Assignee: Trinity Airweighs LLC (Crane Company)
• Inventors: Nance, C. Kirk
• Primary Examiner(s): OEN, WILLIAM L
• Application Number:
  US09/577,067
• Time in Patent Office: 491 Days
• Field of Search: 731/78.T, 738/65, 701/124, 702/98, 702/173, 702/175
• US Class Current: 73/178.00T
• CPC Class Codes: B64D 2045/008 Devices for detecting or indicating hard landing
• CPC Class Codes: G01G 19/07 for weighing aircraft
• CPC Class Codes: G01M 1/125 of aircraft

Abstract

An onboard system for use in measuring, computing and displaying the weight and center-of-gravity for aircraft, while keeping aircraft movement to a minimum. Pressure sensors are mounted in relation to each of the landing gear struts. An onboard pump and reservoirs are attached to each of the landing gear struts and are activated by a computer/controller, while landing gear strut pressures are monitored in the determination of strut stiction. The computer/controller calculates the stiction of each landing gear strut and compensates for the pressure distortions caused by landing gear strut stiction. Additional features include reducing strut stiction, measuring landing gear strut fluid levels, monitoring landing gear strut health, weight adjustments for external ice and de-icing fluids, weight adjustments for wind, monitoring aircraft landing gear strut movement.

Claims

1. A method of determining the relative amounts of gas and liquid in an aircraft landing gear strut, comprising the steps of:

a) changing the amount of fluid in said strut;

b) measuring the pressure in said strut while changing the amount of said fluid;

c) determining the rate of change of pressure in said strut;

d) determining the relative amount of said liquid to said gas from said rate of change in strut pressure.

2. The method of claim 1 wherein the step of determining the relative amount of said liquid to said gas further comprises the step of comparing the measured rate of change of pressure of said strut to a look-up table of known rates of change in pressure.