One of Curiosity’s two wind sensors was apparently damaged in landing and is inoperable.
The Rems team first noticed there was something wrong when readings from the side-facing boom were being returned saturated at high and low values. Further investigation suggested small wires exposed on the sensor circuits were open, probably severed. It is permanent damage. No-one can say for sure how this happened, but engineers are working on the theory that grit thrown on to the rover by the descent crane’s exhaust plume cut the small wires. The wind sensor on the forward-facing mini-boom is unaffected. With just the one sensor, it makes it difficult to fully understand wind behaviour.