The K-MAX was selected because it can carry over 2, 700kg, which is more than its unladen weight.

ECONOMIST: Autonomous helicopters

The K-MAX has a four-hook carousel, so it can drop off supplies at several locations in one mission.

ECONOMIST: Autonomous helicopters

In its unmanned form a K-MAX might fly for most of the day.

ECONOMIST: Autonomous helicopters

The unmanned K-MAX carries its cargo externally on a 25-metre cable.

ECONOMIST: Autonomous helicopters

The K-MAX then delivers its cargo to within three metres.

ECONOMIST: Autonomous helicopters

The top speed of the K-MAX is only about 100 knots (115mph), but it has all the virtues of unmanned aircraft: it never gets sick, tired or goes on leave.

ECONOMIST: Autonomous helicopters

Unlike many large fixed-wing drones, which are flown under remote control by ground-based pilots, a modified K-MAX flies autonomously along a programmed course using GPS to navigate via specified way points.

ECONOMIST: Autonomous helicopters

Terry Fogarty, in charge of unmanned systems at Kaman, says that the single-pilot-manned K-MAX can be flown up to 12 hours a day on logging operations, requiring a change of pilots.

ECONOMIST: Autonomous helicopters

At present the K-MAX has no defensive systems, but Lockheed Martin says the helicopters could easily be fitted with armour, machine-gun pods or flares which could be fired as decoys to divert ground-launched missiles.

ECONOMIST: Autonomous helicopters

Among the U.S. companies logging on are Disney, K-Mart, Office Max and Toys "R" Us.

CNN: MIDDLEMEN, BEWARE

Some ways to do that are to max out pre-tax deductions in your 401(k), defer current income with deferred compensation, and delay your bonus (if your employer allows this) to 2014 instead of taking it in the current year.

FORBES: Will The 3.8 Percent Obama Care Surtax Apply To Me?