| 摘要 |
An aircraft (101, fig 1) has main landing gear (105, fig 1) and nose landing gear (106, fig 1). Each landing gear includes a dual stage suspension strut 201 comprising a hollow cylindrical upper part 202 and a hollow cylindrical lower part 203 sliding within the upper part. The interior chambers 209, 210 of the two parts are filled with a hydraulic fluid 211 and a gas 212. A valve 207 in the top of the upper part allows insertion or extraction of fluid from the chambers. A valve 217 at the bottom of the lower part allows filling or emptying of gas 218 from a lower chamber 210. The fluid level in the strut needs to be maintained while some is lost during use. The fluid level is calculated as a function of the closure C of the strut and is replenished accordingly. An automatic servicing cart 107 can be connected to valves 207, 217 together with temperature sensors 311,312 and pressure sensor 313 together with ultrasonic sensor 314 and digital micrometer 315 to enable the correct quantities of liquid and gas to be delivered to the strut. The servicing cart includes gas and hydraulic fluid 306,307 supplies and is controlled by a processor 301. |
