Hi all. I'm new to the forum and currently building a Dynaflight Bird of Time. I have an ARDU 2.5 and sourcing components to complete the project. I know this has to have been discussed before, but can't seem to find any links to previous discussions. So, arduplane doesn't appear to support sonar, but arducopter does. Any reason why? I am primarily looking at sonar for landing flair. I've also looked at a miniature laser range finder from FLIR systems, but afraid to ask about the cost (well, I will, but I know it will be pricey). I've also seen some DIY range finders using a laser pointer and camera. But sonar seems an inexpensive solution if it can be made to work on a fixed wing airframe. Anyone have any suggestions? Cheers!