Commercial delivery drones are already taking flight, but before the system really gets off the ground, there are plenty of big-picture details to sort out. Recent patents are starting to fill in some of those blanks, with companies working on systems to transfer cargo from drone-to-drone in midair, airships that drop drones closer to their targets, and lamp posts that double as recharge stations. Now, Amazon has outlined plans to pack parachutes into shipping labels, so packages can be safely dropped as the drone buzzes by.

According to the patent, the label should be about the same size as a regular one, and fairly inexpensive. The difference is that folded up inside this one is a parachute, connected to the package with cords made of nylon, cotton or, in the case of heavy objects, Kevlar. When the drone arrives at its destination, it simply drops the package, with a piece of string pulling the parachute open as it falls.

The plan should save the drone the risk of trying to land on a doorstep or in a yard, instead hovering at a safe distance overhead. Clear symbols printed on the top of the parachute, like QR codes or barcodes, could allow the drone to monitor the package's descent, to make sure it lands safely.

Of course, this kind of system isn't a case of one size fits all. The parachutes could come in a range of sizes, to suit how big, fragile or awkward the items being dropped off are. Things like towels or baseballs might not need a parachute at all, Amazon says, while wine glasses may need a much gentler fall cushioned by extra padding in the box. Awkward packages like poster tubes, meanwhile, might need two separate 'chutes.

If the drone can't get to the drop site, square or rectangular parachutes might help it release the package at a distance and send it gliding diagonally downwards. To keep the box from spinning or the cords from tangling up, Amazon has outlined a few different designs, like arranging the cords in a radial pattern, or attaching a harness to them.

As with any patent, there's no guarantee your future online orders will be air-dropped by parachute, but it could form an interesting piece of the drone delivery puzzle.

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