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In 2002, a stroke-like event turned Henry Evans into a quadriplegic, depriving him of almost all ability to move. Eleven years later, a remote-controlled aircraft has given the former Silicon Valley finance officer a new kind of mobility.

"I distinctly remember lying in bed, wanting to go outside, when it occurred to me that I didn't need my whole body, just my retinas," Evans recalls. He posted a note online asking for help, and he got it -- in the form of a drone. "I flew around my vineyard, tried to land on a basketball hoop, inspected the solar panels on our roof and came in second in a pole-tagging contest. It was the ultimate exercise of free will."

Although most people don't face the limitations Evans does, many of us stand to benefit from drones: lightweight, remote-controlled or self-controlled aircraft that offer an inexpensive eye in the sky. Real estate agents can capture aerial photos of homes for sale, oil companies can easily inspect miles of pipelines, and farmers and ranchers can quickly check fields and livestock without doing a visual survey on foot.

For filmmakers and extreme-sports videographers, drones can deliver exciting new perspectives. For ordinary folks, drones can let us see what it's like to be a bird. Sports fans already got a glimpse of that, thanks to drones at this year's World Cup.

These possibilities and more explain why consumers and businesses are snapping up drones, even though the US Federal Aviation Administration limits their commercial use.

Ready for takeoff

"The consumer space is going to explode," predicts Peter George, vice president of sales and marketing for Paris-based Parrot, the top maker of consumer drones. It has shipped more than 750,000 drones since its first quadcopter in 2010, and George says the company won't be surprised if shipments double annually for the next five years. It expects to sell about 200,000 this year.

Drones typically follow a preset flight plan or are operated by a person with a remote control. They range from large, missile-equipped military-airplane-like models to hand-sized toy quadcopters, with four propellers that point up. Hobbyists favor models the size of a pizza box that cost a few hundred dollars.

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Onboard electronics carefully control propeller speed, letting drones ascend, descend and even perform stunts such as flips. The upcoming Parrot Bebop has a built-in camera; others such as DJI's Phantom or 3D Robotics' Iris can be outfitted with small cameras. Bigger drones can tote SLR cameras or 3D laser scanners.

Since the days of film cameras, SkyPan International founder Mark Segal has used a homemade drone to photograph high-rise building sites. He shows prospective investors and buyers exactly what the view from the 30th floor will be. "This has been my life's work," says Segal, who just finished taking panoramic photos of a Honolulu parking lot slated to become a multitower Howard Hughes Corp. development.

Businesses hunger for "a camera in the sky covering millions of acres and thousands of construction projects," adds Rich Levandov, a venture capitalist at Avalon Ventures. That's why he invested $10 million in SkyCatch, a startup that uses drones to gather data. Some of SkyCatch's biggest clients are in construction and oil and gas, and they're looking for what Levandov calls "site truth."

"They want to see what's going on with progress," Levandov says. "Are supplies showing up? What are the crane locations?"

Bezos' flying brigade

The highest-profile drone idea isn't about remote viewing, however. E-commerce giant Amazon wants to deliver products weighing less than 5 pounds -- the bulk of what it sells today -- with drones that can fly as far as 10 miles from its fulfillment centers.

"I know this looks like science fiction," CEO Jeff Bezos told CBS' "60 Minutes" last year after announcing his plans. "It's not."

CBSNews.com/Screenshot by CNET

Although Amazon's Prime Air is still years away, many would be thrilled with fewer delivery trucks on the road and more-immediate online-shopping gratification. But the challenges are immense.

"This service would be about as commonplace as people taking a private helicopter to work," argues Victor Allis, chief executive of Quintiq, a supply-chain specialist. Even drone fans are skeptical. "I can't see that commercialized," says Parrot's George. "That's at least 20 years away."

Even if homeowners build delivery chutes marked with digital barcodes so Amazon can find them, the drones still must navigate trees, people, birds, snow -- and other drones. Amazon's distribution centers are on cheap land, far from city centers and wealthy suburbs. Drones could startle drivers, and their propellers could injure children.

"Customers do want rapid delivery for certain items, and this will happen -- but probably on a motorbike," predicts Phil Rooke, a pilot and CEO of e-commerce company Spreadshirt.

One startup is even more ambitious than Amazon. Matternet wants to build a vast network of delivery drones, focusing initially on urgent, 5-pound loads to roadless rural areas and congested cities. Using interlinked base stations where drones swap batteries and manage their loads, Matternet claims delivery costs will be just 24 cents for a 6-mile range. In August, Google revealed Project Wing, a delivery service whose drones would hover and spool packages down a line to their destinations, instead of landing.

Even so, drone commerce faces a big hurdle today: It's illegal in the US. The FAA permits personal drone use, but generally not business uses. It's given permission only to two pipeline-monitoring projects in the Arctic and six moviemaking companies.

A changing regulatory landscape? Maybe.

"If the FAA were to give approval today to [drones] that are 55 pounds and below in agriculture, moviemaking, and pipeline and power line inspection, there would be thousands operating before the sun sets," says Mark A. Dombroff, who leads drone work at law firm McKenna Long & Aldridge and previously advised the FAA at the US Justice Department.

Later this year, the federal aviation administration plans to release draft regulations to marry today's airspace with tomorrow's drones. The final regulations are due in September 2015, but most drone watchers don't expect the FAA to deliver on time.

"It's very slow, understaffed and has very under-experienced people who change positions too fast," says SkyPan's Segal. The FAA's staff needs "constant re-education."

The agency admits that crafting regulations is difficult, and that's without taking into account the inevitable barrage of contentious public comments from skeptics and advocates. "We're trying to write regulations for a rapidly evolving technology and trying to keep today's extremely high safety level in the most complex, busy airspace in the world," says FAA spokesman Les Dorr.

Add to that the general feeling that the FAA is ill-equipped to enforce the regulations it does produce. "They don't have a policeman on every corner," says Ladd Sanger, a lawyer with Slack & Davis who has represented dozens of clients involved in air crashes.

Take a number

The FAA is getting more involved. First, the moviemakers' process offers a template for others seeking permission, and the FAA may expand the approach to other industries, Dombroff says. Second, broader regulations are due in 2015.

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But drones can empower others too, including law enforcement, the military, students -- and privacy-invading peeping toms, some fear. High school student Chris Shephard posted notes on people's doors in Mansfield, Texas, seeking his drone after it fell during a student film project. When resident Karen Meister saw the note, she feared the worst -- "pervs" peering into her backyard -- and said she'd destroy the drone if she found it. It ended amicably, but it won't always. Even imagery captured with innocent intentions can infringe privacy.

Privacy? Safety problems? Should we even bother with drones? Yes, says the quadriplegic who uses them to see -- not just outside his house, but across the country.

"Every new technology initially carries questions of whether it will be used for good or for evil," Evans says. "Eventually, use of almost every new technology is properly regulated and allowed. This will happen soon with drones. They enrich too many lives."

Editors' note: This story first appeared in CNET Magazine November 3, 2014.