Launching a high-altitude balloon can be an amazing learning experience and very fun, but if you’re not careful you might end up breaking some laws! Luckily, with a proper understanding of the relevant rules and regulations, it’s easy to make sure your balloon and payload is safe and legal. Almost all amateur balloon payloads, including all those sold by Loonar, are designed to be exempt from FAA regulations so that you’re not required to do any of the stuff listed below in order to launch! However, if you’re looking to fly larger custom payloads, here’s what you need to keep in mind:

Cellphones Off Before Flight

Before we get into any FAA regulations, there is one rather familiar rule from the FCC which even balloons must follow: no cellphones may be operated while airborne. Some people do use a cellphone GPS to locate their payload after landing but such systems have to be carefully programmed to make sure no signals are sent while the balloon is flying. Loonar kits use VHF radio and satellite communications rather than cellular so are allowed to send and receive data for the full duration of the flight.

FAA 101: Exempt or Not?

The FAA has specific regulations regarding the launching of what they call “free unmanned balloons”. Here they are in full if you enjoy verbose legal speak: FAA 101, Official. Their regulations cover not only free unmanned balloons, but also:

• Moored balloons (balloons more than 6 feet in diameter tied to the ground)

• Kites (more than 5 pounds)

• Amateur rockets (except fireworks)

• Model airplanes, helicopters, and gliders

You only need to care about the regulations for free unmanned balloons, but only if they apply at all. Regulations don’t apply if your payload meets these conditions:

• Your payload is less than four pounds

• Or, your payload is less than six pounds and the smallest surface is more than 36 square inches (6 inches by 6 inches)

• If you have two payloads, they weigh less than 12 pounds together

• If you have a rope, it takes less than 50 pounds of force to break it off (just don’t use carbon fiber, regular rope should be fine).

If you meet these conditions, then congrats! You’re FAA 101 exempt. Almost all amateur balloon payloads are exempt and not subject to the requirements of the regulations. All of our payload options at Loonar Technologies are designed to be FAA 101 exempt, but always check if additional payload items you add, like a camera or scientific experiment, push your payload above four pounds!

You aren’t required to notify the FAA for a FAA 101 exempt flight, but it’s good practice if there’s >50% cloud cover. You don’t want to accidentally hit a plane!

FAA 101 Requirements

If you didn’t meet the exemption conditions, you’ll need to take some more care to ensure a safe launch.

There are a couple obvious ones, like don’t launch in a prohibited or restricted area, or in a place where you’re likely to fly into a prohibited or restricted area. There’s a handy map available for drones, but it’s applicable to balloons too.

U.S. Air Space Map (AIRMAP): Prohibited or restricted areas
U.S. Air Space Map (AIRMAP): Prohibited or restricted areas

Another obvious one is don’t be a hazard! This one is a bit ambiguous but, for example, requires that you don’t drop objects if they could be hazardous to people or property below. Dropping something like a paper airplane is fine, but dropping your payload without a parachute is a no-go.

There are other more specific regulations on how and where you can launch:

• Don’t launch where the cloud cover is >50% or if horizontal visibility is less than five miles

• Make sure the first 1000 feet of ascent are not over a congested urban or residential area

• Check your projected landing site, make sure it will not create a hazard for people or property there (like landing on a road or residential neighborhood) and USE A PARACHUTE

• Don’t launch (without a prior waiver from the ATC — air traffic control) if your balloon will pass through Class B, Class C, Class D, or Class E airspace designated for an airport below 2000 feet (check SkyVector for airspace maps)

And more guidance about how you to safely outfit your payload:

• Two independent cutdown systems/devices (that separate the payload from the balloon) that you have to be able to manually activate if cloud cover increases above 50% at the altitude where you are flying or if your payload malfunctions and might cause a hazard to planes

• Lights which are visible for at least 5 miles and flash between 40 and 100 cycles per minute (once per second is a good medium)

• If you have a trailing antenna, line, or other suspension device, you need to tie on colored pennants or streamers in alternating bands of highly conspicuous colors (think neon) spaced 50 feet apart (or less) and visible for at least a mile

• A radar reflective material/device that will reflect 200 MHz to 2700 MHz such as the reflector pictured below

Example of a cheap but effective radar reflector made from cardboard and aluminum foil
Example of a cheap but effective radar reflector made from cardboard and aluminum foil

FAA Notification

Once you’ve got your non-exempt payload all up to code, you have one more checkpoint before you can launch it: notifying the FAA. There are a couple steps in this process:

1. Chose your launch site (remember to avoid airports and congested regions, the SkyVector website is helpful for that)

2. Find out the FAA contact for your region (Look up FAA contact info here)

3. Draft up a “launch specification” with details about your payload and the launch (see below for more info)

4. Send them an email with your launch specification at least 3 days before your launch, and ask for the ATC numbers you should call 20 minutes prior to launch (if this is your first launch in the area, start this process at least a week before for buffer time)

5. They will email back with questions or approval and give you the relevant numbers you need to call

Make sure you call the numbers they gave you at the right time before the launch and follow any instructions they give you. Here’s an example of what you should say:

“Hi my name is [name] with [organization]. I’m calling to report a high-altitude balloon launch from [location] in 20 minutes at [time].”

They may ask you for more details like the estimated ascent rate, direction of travel, or burst altitude. Make sure you know that information offhand.

Also, don’t forget to notify them if you decide to cancel or “scrub” the launch!

Launch Specification

The document you send to the FAA contact should include:

• Your launch site (latitude/longitude, park name, nearest town)

• Estimated date and time of the launch (if you have to delay, notify them again)

• Target burst altitude (usually about 25–30 km)

• Estimated ascent rate (usually about 2–5 mps)

• Estimated flight duration

• Balloon identification (amateur radio callsign)

• Balloon diameter

• Rope length

• Payload weight

• Trailing antenna length

• Map of the predicted balloon trajectory (use the CUSF flight predictor, but remember, it’s in UTC!)

CUSF High Altitude Balloon Flight Predictor: Example trajectory
CUSF High Altitude Balloon Flight Predictor: Example trajectory


Sometimes the FAA may ask you to file a NOTAM, a notice to airmen, between 3 days and 24 hours prior to launch. This notification goes out to all pilots operating around your launch site so they’re extra vigilant and watchful for your balloon. Contact Leidos Flight Service Station at (877) 487–6867 and provide the following information:

• Date and time of launch

• Location of the operation in degrees, minutes, seconds

• Affected altitudes: surface to (provide maximum altitude expected) and anticipated trajectory.

• Any additional information requested

Balloon Position Reports

Since standard balloon flights typically only last 2–4 hours, reporting your position to the FAA isn’t usually too difficult. Record the location of the balloon at least every two hours and report that to the ATC if they request it. If you can’t get a communication from your balloon for more than two hours, call the ATC and give them the last recorded position and projected trajectory, then notify them immediately when you get signal from the payload again.

One hour before descent (usually right before the balloon is about to pop), you should call the ATC you notified earlier with:

• Current location

• Current altitude

• An estimated time when it will hit 60,000 feet (18.29 kilometers)

• The forecast time and location of landing

Finally, notify them again when the balloon payload has landed!

And that’s all it takes! It might seem like a long list at first but after going through it once or twice it becomes second nature. Then you’ll be able to safely and completely legally launch any balloon payload that you can put together!

Loonar Technologies

Loonar Technologies sells high-altitude balloon kits. Perfect for educators or hobbyists, our advanced avionics — complete with two-way communications and a mission control suite — make it possible for anyone to get to near space. See for more info!

    Loonar Technologies

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    We’re a High-Altitude Balloon startup that sells easy-to-use educational kits. Order one of our kits at and launch in minutes.

    Loonar Technologies

    Loonar Technologies sells high-altitude balloon kits. Perfect for educators or hobbyists, our advanced avionics — complete with two-way communications and a mission control suite — make it possible for anyone to get to near space. See for more info!

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