More questions arising...
Radioaltimeter on EC135. I can't seem to find it in the supplement section of FLM to find answers to my questions. We fly NVG and from time to time rely on radioaltimeter for operational usage. I've noticed that the system does not detect trees or rough terrain. For example as we fly over trees the relative height indicated is not to the tree tops but mostly to the ground. That could be a 100ft difference when we would already be scraping the tree tops. I'm not use to having this problem on our older models (212, 412). I was told from our engineers that bell uses first radar echo as a indicator of height no matter how small the surface under the radar is. As EC135 has a logic of average surface area from echo. For example if a tree is right under the radio altimeter and the ground is a 100 below, the system will due to trees smaller surface average out the tree to a few feet only thus showing slightly less height than the height to the ground is.
Any clue or literature on that EC135 radio altimeter logic?
Second question is also the kind that I could not find in any manual. I know that I could access inflight EPC resoults from maintenance menu but I can't seem to do that now. I follow the procedure published in training manual but the inflight EPc resoult menu is empty when the system asks me for the flight number. I'm not sure if the EPC inflight tests are done regulary as we have 8 pilots flying one helicopter. I know that the flight report only shows the data for last 30 flights from maintenance menu. Is that the case with EPC menu also?
Thank you!