Connect with us

Drone Articles

US military wants quieter drones




Drones are noisy machines.

If you own one, have been around one or have just seen one in a video, you’ll know that during takeoffs and flights drones emit a persistent, fairly annoying buzzing or whirring sound.

When it comes to consumer drones, some are quieter than others. Don’t get it twisted though- the sound they make is not a whisper, it’s more like low-level tinnitus.

What about military drones? Are they loud?

As a matter of fact – yes. They’re very loud. We truly hope you’ve never been in close proximity to a predator drone – those things are killing machines that rain death from the sky. In case you don’t know what they sound like, check out the video below:

Okay – we get it. Drones are noisy. How is the military planning to make them quieter?

Was just setting the scene. Chill

Ever heard of Felix Wankel? Neither had we. Aside from having an unfortunate surname, this man was responsible for creating a revolutionary aircraft engine in the 1960s. According to Military Times, Wankel’s engine was compact and produced higher speeds and more power than other engines of its day.

The Wankel engine, however, never really caught on. Was it the name? Was it terrible fuel efficiency and the fact it burned too much oil? It could be either, it could be both.

A new company called LiquidPiston Inc grabbed themselves a Wankel, inverted it and changed the name to X4 (a great decision). The company believe their new version, which is intended for predator drones, will increase flight time by more than 50 percent, meaning more killing and less downtime. Company CEO Alec Shkolnik says this new propulsion system can reduce a drone’s engine heat signature and minimize vibration impact. Essentially – it travels quieter than average drones. Again, it’s not like it will be totally silent; just a lot quieter than what you hear in clip of the drone above.

The United States’ Defense Advanced Research Projects Agency (DARPA) is highly interested in the X4 and have granted LiquidPiston $2.5 million to continue the research and development of their engine.

Technical stuff

LiquidPiston’s X4 engine.

The X4 engine has an oval rotor inside a triangular chamber. Combustion occurs at fixed points within the chamber making it easier to lubricate without burning oil. This design allows the engine to be five to ten times smaller than a standard combustion engine and will only weigh 30 to 40 pounds lighter.

The engine is currently in its second phase of testing and that will be finished by October. After that LiquidPiston will look for a partner to help the engine be realised in UAVs.

It’s not an automatic assumption that advances in military drone technology will translate into quieter consumer drones. One would assume, however, that advances in military technology do eventually flow through to mainstream and there is an incentive to make consumer drones more friendly for your ears.

We will keep you updated on any future developments.

Prev Page1 of 2
Use your ← → (arrow) keys to browse


Our Videos