Perhaps the most frequent drone question we get at MAXSUR is, “Which drone is the most quiet?”. Secondly, “How low can the drone fly and still maintain a degree of stealth?”. To date, very few people have answered those questions outside of general vagaries. To provide more objective answers, the MAXSUR team conducted a drone noise level test and the results were very surprising.
Before we get into the details of the test, I want to address an obvious reason why there are little details about noise levels and drones: Most people in the community have a fear of being labeled with the “big-brother” tag. The drones we are testing are common off-the-shelf drones, and are far from the million dollar-plus military drones that are used for covert surveillance. These off-the-shelf drones however are commonly used by public safety and are always used in response to someone or something occurring. In those responses, a life-saving tactic may be to limit detection from a bad guy. These drones are excellent for such events but are very poor at being used for persistent surveillance, like unto military-class drones.
To keep the test as “real-world” as possible, we ditched the normal decibel meter used for noise level testing. After all, there are many more scientific factors involved beyond simple dB levels. The factors we focused on were:
Obviously, the higher the drone the better in terms of stealth. However, the higher you go…the less information you’ll be able to obtain about ground information e.g. identity, lp’s, and activity. So, in our test…