A hang glider can be foot launched from a hill or cliff, or towed behind an ultralight airplane, truck or boat. They can also be winch launched.
How high can you go?
Most flights remain below 1350 - 1800 meters (4000 - 6,000 feet). In the USA the legal, regulatory limitation is 17,999 ft above mean sea level (MSL). Above about 3,000 - 4000 meters (9,800 - 13,000 feet) you will need oxygen.
How long can you stay up?
An intermediate pilot can soar for several hours. Hang Gliders remain aloft by using ridge lift (rising air deflected by a mountain) or thermals (rising air created by the sun warming the earth). An advanced pilot may choose to fly cross-country (XC) and fly many miles to "land out."
Cross-country (XC) records are often hundreds of miles, and the world record for soaring is over 24 hours!
How do you control the glider? Is it difficult?
Hang Gliders are controlled by "weight shift" much like motorcycles, skis, or skates. It's not difficult, but requires a learning period, much like balancing and riding a bicycle. It will become second nature with practice. The key to controlling a hang glider is not strength, but balance, endurance, and a light touch.
What happens if you stall?
A stall happens when the glider is not moving fast enough to maintain lift and flight. A minor stall can make the glider difficult to control, while a full stall can result in a loss of 15-100 feet (or more) of altitude. Stalls are not as dangerous at high altitudes, and are often a good teaching tool, and loads of fun. Stalls are dangerous when the glider is near the ground, since losing altitude can cause the glider to crash. When landing a hang glider, always maintain your speed.
What if you fall?
The hang glider pilot is tethered to their glider by a strap capable of holding over 10 times the person's weight. Falling out of the glider is not likely. Gliders themselves do not fall unless they suffer structural damage, or are not properly assembled. Glider damage is caused by improper glider maintenance, or performing aerobatic stunts that over stress the glider. Hang Gliders are very sturdy, usually composed of aircraft aluminum.
How much does it cost?
Lessons: $70 to $140 per lesson, including equipment rentals
Older gliders as cheap as $300, are not recommended since they are difficult to fly or repair
Quality used gliders start around $1500
Beginner gliders start at $3000
Intermediate gliders start at $4000 and run up to nearly $10,000
Equipment: Helmet, harness, etc. will run another $500 to start
Never buy any hang gliding equipment without first consulting with an instructor!
Do I need any kind of rating or certification?
Hang Gliding is a self-regulated sport, so no official certifications are required by law to own or operate a hang glider. However, most launch sites and landing zones appropriate for hang gliding require a certification by the United States Hang Gliding and Paragliding Association (USHPA). Failure to follow site guidelines can result in sites being shut down, angry pilots, and legal action. Always check site guidelines before flying.
The USHPA has pilot proficiency system that consists of 5 levels, Hang-1 through Hang-5. Certified USHPA instructors can witness your flight, administer a short written test, and provide you with a rating. Filing fees are $15, and provide a pilot with instant insurance and international recognition of their skills. Here is a brief summary of each rating:
The pilot can safely setup/breakdown a glider and perform straight and level flight at varying airspeeds.
This allows the pilot to fly training hills without an instructor.
The pilot can control the glider in turns and has more advanced launch and landing skills in a variety of flying conditions.
This allows the pilot to fly most mountain sites and tow parks, under supervision by an observer.
The pilot has 10 hours of air time, understands right-of-way rules, wind and site conditions, spot landings & approaches.
This allows the pilot to fly nearly all mountain sites and tow parks.
Must have significant experience with extended flights and thermals at a variety of intermediate sites.
The pilot has years of experience and their mentoring skills allow them to be an observer.
Pilot is probably a competition pilot, with tandem flights, cross-country flights, and all special skills sign-offs.
The pilot is likely an instructor with a decade of experience.
Technically you can fly a hang glider anywhere except where you are explicitly not allowed, such as National Parks and Forests (Yosemite being an exception). BLM generally allows hang gliding on its land. You should of course get permission on any private land you wish to fly on. You will fly under FAR Part 103 which prevents you from flying in controlled airspace and over congested areas. The majority of hang gliding occurs at well established club sites.