Right off the top I am going to say that we are newbies so we are learning all the ins and outs on the fly. In this scenario we had been flying in free flight just grabbing some video for an upcoming construction project area. We were monitoring the battery level and had planned on landing the drone at 10%. Since we were in free flight mode it never occurred to us that the RTH feature would still be monitoring battery needed to get back to take off point. We were flying at about 20' above ground when the drone decided it needed to RTH at 13% battery. The drone began to ascend towards the tree canopy overhead. Before the pilot could process what was happening the drone had struck a limb and fell to the ground. So my purpose for this inquiry is to simply ask, am I the only one who is confounded as to why the engineers would kick the drone into program flight mode without turning on the obstacle avoidance protocols as well? Also, the battery seems to have taken the blunt of the impact so it is now showing one green light at the top (furthest from the on/off button) and on red led at the bottom. I have tried the hard reset with no success. Any one know off hand what this particular pattern of led suggests the problem is?