Patent ID: 8789415

Claim:
A gravity gradiometer comprising: a detector for detecting a gravity gradient, the detector comprising at least two movable sensor masses and being arranged for rotation about an axis, the detector being arranged to generate a signal in response to a change in the gravity gradient, wherein the at least two sensor masses form an Orthogonal Quadruple Responder (OQR) and experience a change in torque in response to the change in the gravity gradient whereby the at least two sensor masses move relative to each other and wherein the signal is indicative of the relative movement of the at least two sensor masses; a support structure for supporting the detector in an aircraft and comprising a component that is arranged to reduce transmission of an aircraft acceleration to the detector, the support structure comprises a first support structure component and a second support structure component and wherein the first support structure component is arranged to support the second support structure component, wherein one of the first and second support structure components is arranged to reduce an influence of the aircraft acceleration on the signal by a factor of at least 10 1 and the other one of the first and second support structure components is arranged to reduce an influence of the aircraft acceleration on the signal by a factor of at least 10 2 ; and further, wherein the at least two sensor masses are arranged to reduce the influence of the aircraft acceleration on the signal by a factor in the range of 1×10-1×10 4 .