The one thing every remote pilot fears above all is a crash, particularly a crash from a substantial altitude that can devastate a quadcopter. But in a moment of complacency and overconfidence, I flew my DJI Air 2S sideways directly into a 80-foot tall aspen tree.
DJI promotes the safety of the Air 2S because it features obstacle avoidance sensors in four directions. Unfortunately, it is the lack of side-facing sensors that allowed me to send my aircraft into the devouring branches of the towering aspen. But I can’t blame DJI-I knew that I was flying near the tree and that I was flying sideways, yet I was so overconfident that I didn’t really pay attention until I heard the loud smack of propellers on solid wood.
The impact tore off one set of props, broke another set in half, and caused the motors to immediately shut off. I heard a subsequent thump when the drone hit the ground under the tree. When I looked at the camera view on my phone, the screen was black, and I assumed the camera was demolished.
The ground surrounding the trees was overgrown with ferns, and I had a hard time locating the drone so I activated “Find My Drone” and was relieved to hear it beeping which at least meant something was still functioning. The drone was easy to find at that point. Along with the aforementioned prop damage, one of the rear arms was folded but not broken, and the camera gimbal was in some sort of disconcerting spasm. I rushed to power off and reboot the drone hoping to cure this issue or more likely confirm a diagnosis of irreparable gimbal failure, and I guess this is why I didn’t think to snap a photo of the drone at the crash site.
I breathed a huge sigh of relief when the battery powered on and the gimbal went through the startup exercise routine that all DJI pilots know so well and the live feed from the camera appeared on my phone screen. I powered it off again and performed a more thorough inspection of the aircraft. Aside from what appeared to be significant scuffs on the body of the aircraft (but later wiped off with a damp paper towel), only the Freewell VNDxMist filter appeared to show any damage (although what appeared to be deep scratches on the surface of the filter were easily removed later on with some lens cleaner).
The next test was a return to flight with a new set of props, and I was very happy when the aircraft took off with no issues. Ordinarily I would have landed and called it a day, but I was on-site filming for the Cuchara Mountain Mercantile and decided to continue very cautiously paying careful attention to ensure I was flying well above the height of the trees. There did not seem to be any lingering issues with either the flight controls or camera.
After returning home that evening, I decided to inspect the drone once again while cleaning off all the debris from the tree encounter and subsequent impact with the ground. I found that one of the rear legs has a little more give, although I’m not sure which one was folded after the crash, but just about all of the scuffs and scratches wiped off the body. I decided to test if there were any potential flight control issues caused by the ”weaker” rear leg by flying the drone erratically in Sport mode at low altitude in the front yard-neither of the rear legs collapsed.
I had to return to the Mercantile the next morning to get some additional footage, and I did encounter a couple of little glitches during those flights. First, I noticed a little bit of stuttering in the live feed on the phone screen for just a moment, and later on the gimbal did momentarily freeze up during one maneuver. This does still have me a little concerned, but I haven’t encountered this issue in subsequent flights so far.
I’ve also tested the camera by capturing a number of low light still photos. For the most part, these have turned out excellent. Flying over Big Meadows Reservoir I captured several AEB sets at shutter speeds down to about 1/8 second with no apparent issues. I also captured some twilight shots of my friend’s cabin near South Fork with exposure times up to 20 seconds with sharp results up to 8 seconds. Of course, several of these multi-second exposures are blurred, but many of them are quite sharp demonstrating that the gimbal is functioning well.
Some of these long exposure images show some strange coloration or digital artifacting that appears as a magenta or green tint along the bottom and top of the image, but it is not present on all of these images. The examples below show the edited images where the discolorations are apparent and the unedited raw exposures showing just how dark it was at this time. This discoloration could indicate some kind of damage to the camera sensor but could also be an artifact of the drone’s navigation lights reflecting off the surrounding trees or maybe a vignetting issue caused by the presence of the VND filter on the camera (here’s a similar example).
Because the colors change on different photos and are not present on some, I think this is caused by the navigation lights on the legs of the aircraft. I confirmed that the lights (front and back) continue flashing while capturing long exposure photos, at least when the obstacle sensors are picking up a nearby object which was the case when taking these photos. Also, the option to turn off the LEDs while taking images is not found in the DJI Fly app. These exposures were captured in very dark conditions with the VND filter attached, and I’ve seen no other issues in any of the other photos captured since the crash. So I think this is not an indication of sensor damage.
At this point, I’m feeling very fortunate that my aircraft did not sustain significant damage in the crash although I’m still hesitant to declare that it was not damaged at all. The day I received my original Mavic Pro in January 2017, it crashed into a tree near my house and the subsequent impact with the concrete steps completely destroyed the gimbal. I was fortunate that day that DJI determined the crash was not caused by pilot error and replaced the drone under warranty, and I never crashed that drone again over the next 5-1/2 years. I hope that this incident has taught me to be more vigilant when flying the Air 2S and that it will be the last crash for this aircraft as well.