Aircraft landing gear spring assembly

An aircraft landing gear suspension system comprising:

• a loading point for receiving a load from one or more wheels or skids;
• and
• a spring mechanism including:
• a first leaf spring having a first end region connected to the loading point and a pivot point mounted to a support for an aircraft landing gear;
• a link connected to a second end region of the first leaf spring, wherein the pivot point of the first leaf spring is between the first and second end regions, and
• a second leaf spring having a first end region connected to an interface of the support for the aircraft landing gear, and a second end connected to the link;
• wherein a spring rate of the second leaf spring is less than a spring rate of the first leaf spring, and wherein the spring mechanism is configured so that, during application of an increasing load to the loading point, a spring rate of the spring mechanism changes from a first spring rate to a second spring rate and then to a third spring rate, the second spring rate being less than each of the first and third spring rates.

A method of operating a landing gear spring assembly, the spring assembly including an interface connecting the spring assembly to a support in an aircraft, and a spring system configured to apply a resilient biasing force to a loading point, the loading point configured to receive a load from one or more wheels or skids of a landing gear, wherein the spring system comprises a first spring element and a second spring element, wherein a spring rate of the second spring element is less than a spring rate of the first spring element, and wherein the loading point is connected to the second spring element via the first spring element, the method comprising:

• applying an increasing load from a wheel or from a skid of the landing gear to the loading point of the spring assembly, wherein the loading point is movable relative to the interface;
• applying, by the spring system, a resilient biasing force to the loading point to oppose movement of the loading point relative to the interface;
• and
• during application of the increasing load to the loading point and the application of the resilient biasing force, changing a spring rate of the spring system from a first spring rate to a second spring rate, wherein the second spring rate is less than the first spring rate.