A brief but informative article on avoiding multicopter technical issues that could help minimize crashes which can cause personal injury and/or property damage appears on scarLiang.com
There is a compilation of crashes video many of which appear to be caused by flying within densely wooded areas along with some good advice in the complete article on the scarLiang webpage.
Briefly, the article advises that "for anyone who has experience of building quadcopters, should be familiar with all the critical parts of the machine. If not please take a look at the quadcopter hardware overview guide. In this post we will discuss some hardware failures that happened to me, and how we could have prevented it." The article lists the main areas of interest as far as failures go as follows:
- Flight Controller
- Radio Reciever/Transmitter (Signal)
- Video Receiver/Transmitter (Signal)