The word "drone" usually brings to mind a surveillance device capable of unmanned flight. For the more military-minded, it could mean bombers capable of destroying targets with pinpoint accuracy. For NASA, it means a biodegradable flight system built using fungi that is capable of melting down — for the most part, anyway.

A team of students, primarily from Stanford and Brown Universities, has managed to successfully design and test a prototype of a drone that has a body made up entirely of a biodegradable component in a project backed by NASA. The biodegradable component takes a week to grow in a special mold and is known as mycelium, the vegetative part of a fungus. The solid, Styrofoam-like body of the substance allows Ecovative Design, the company that grew it, to use the material as an environmentally-friendly alternative in applications such as packaging and surfboard cores. This material, which forms the chassis of the drone, is then coated using cellulose sheets grown by bacteria. In an effort to maximize the biodegradable capacity of the device, the circuits it carries are printed in silver nano-particle ink.

Apart from being environmentally-friendly, as far as unmanned flight vehicles carrying bombs can be, another significant aspect of these drones is the nature of their constituent components. Since the fungi that form the body are alive, they usually are capable of synthesizing their own energy, which can be harnessed to power the drone. This makes the system lightweight as well as largely self-sufficient.

However, while major segments of the design equipment are biodegradable, most of the mechanical components, such as the propellers and the flight controls, are not, and neither is the battery that powers them. These components are similar to the ones found on standard quad rotors. The team continues working on designing sensors that utilize biological organisms to read environmental cues so as to reduce the non-degradable components to a minimum.

Considering the success of the project, it might not be far-fetched to be on the lookout for a few quad rotor blades lying in an unkempt patch of grass. You never know!