US 11,981,424 B2
Trend monitoring of a shock absorber condition
Antoine Guidoux, Gloucester (GB); Jon Smith, Gloucester (GB); Jean-Yves Ravel, Vélizy-Villacoublay (FR); and Yann Simmonneaux, Gloucester (GB)
Assigned to Safran Landing Systems, (FR); and Safran Landing Systems UK Ltd., (GB)
Appl. No. 17/774,925
Filed by Safran Landing Systems UK LTD, Gloucester (GB); and Safran Landing Systems, Vélizy-Villacoublay (FR)
PCT Filed Nov. 10, 2020, PCT No. PCT/EP2020/081659
§ 371(c)(1), (2) Date May 6, 2022,
PCT Pub. No. WO2021/094319, PCT Pub. Date May 20, 2021.
Claims priority of application No. 19208361 (EP), filed on Nov. 11, 2019.
Prior Publication US 2022/0388638 A1, Dec. 8, 2022
Int. Cl. B64C 25/60 (2006.01); B64D 45/00 (2006.01); B64F 5/60 (2017.01)
CPC B64C 25/60 (2013.01) [B64D 45/00 (2013.01); B64F 5/60 (2017.01); B64D 2045/008 (2013.01); B64D 2045/0085 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method of monitoring a condition of an aircraft landing gear shock absorber, the shock absorber including at least one spring chamber containing a gas, the method comprising:
taking a plurality of measurements of a gas pressure and a temperature in the spring chamber, each gas pressure and temperature measurement pair being taken at a same instant relative to an operating cycle of the shock absorber;
determining a first value based on each pair of gas pressure and temperature measurements;
storing the first value in a log;
determining a trend of the first values based on the log, the trend indicating a prediction of performance; and
in response to determining that the trend of the first values is outside a first range of values, generating a first notification signal, wherein measuring the gas pressure and temperature occurs before the aircraft lands.