Drone Laws Blog usually has original writing, but the AMA (Academy of Model Aeronautics) has just released a new article that answers the questions I, like many others, have about becoming a new FPV pilot. The following is from http://www.modelaviation.com/FPVforBeginners. I highly recommend joining AMA and obtaining their liability insurance as a member benefit – Jeffrey Antonelli
Written by Patrick Sherman
As featured in the April 2014 issue of Model Aviation.
The development of FPV, or First-Person View, during the past few years has drawn many new people into model aeronautics, including me. This surge of interest and enthusiasm has brought a new vitality to the hobby—new ideas and a new sense of mission that will ultimately transform RC flying and society. Of course, enthusiasm is no substitute for technical skill and many newcomers don’t know the difference between an ESC and an EC-5 connector.
Here at the Roswell Flight Test Crew, one of our primary goals is to teach people how to build their own FPV platforms. Because most of them fit into this novice category, we usually spend more time talking about how to build and fly aircraft than we do discussing the actual FPV systems.
When Editor-in-Chief Jay Smith of Model Aviation asked me to put together a how-to article about FPV, I jumped at the chance. As AMA members, you already have building and flying abilities, so I can skip straight to the fun part!
STEP ONE: Ham It Up
In order to lawfully utilize the radio frequencies that are required for FPV flying, you will need to be a licensed ham radio operator. This sounds like a daunting first step, but it isn’t the ordeal that it used to be.
In 2007, the FCC eliminated the requirement to know Morse code to become a ham operator. Today, all you have to do is pass a 35-question, multiple-choice test in order to qualify for a Technician license—the first of three levels of licenses available from the FCC and probably the only one you will ever need as an FPV pilot.
There are books and online courses available to help you prepare, but we signed up for a free, two-day class offered by a local ham radio club. To find classes in your area, visit the Amateur Radio Relay Network website listed in the “Sources” section.
If I can pass this test despite having the same level of technical acumen as a half a ton of igneous rock, anybody can do it!
STEP TWO: Choose an Aircraft
Contrary to what you might think from watching online videos, you don’t have to choose a multirotor! I believe that multirotors have become closely associated with FPV flying because both technologies matured at roughly the same time. Because multirotors are stable, mechanically robust aircraft, they were a natural choice for beginners who were drawn into RC flying by the potential of FPV.
Although you don’t need a multirotor, the aircraft does need to be a stable platform—either rotorcraft or fixed wing—with sufficient payload capacity to carry the necessary gear. Helicopters are certainly an option for a skilled pilot, but they tend to induce more vibration to the camera mount than other aircraft types. Foamie trainers and flying wings are popular fixed-wing choices, but we at the Roswell Flight Test Crew favor the ubiquitous multirotor.
Easy to fly and having as few as four moving parts, multirotors such as the Roswell Flight Test Crew’s RQCX-3 Raven hexacopter, are a popular choice for FPV platforms.
STEP THREE: Frequencies
Several frequencies are available to carry the live video feed from your aircraft back to you on the ground: 900 MHz, 1.2-1.3 GHz, 2.4 GHz, and 5.8 GHz. As a seasoned aeromodeler, I’m sure that one of those frequencies set off all sorts of alarm bells ringing inside your head—2.4 GHz, because that’s the same frequency our modern control radios use.
Unless you’re still rocking a 72 MHz crystal radio that you’ve had since 1975, let’s take 2.4 GHz off the list. Alternatively, if you’re using a 433 MHz long-range system to transmit control signals to your aircraft, 2.4 GHz is back on the table.
As a general guide, the lower frequencies (900 MHz, 1.2-1.3 GHz) tend to be more forgiving if a physical object such as a tree comes between the pilot and his or her aircraft. However, the antennas tend to be larger because of their longer wavelengths, which can make them more difficult to mount on your aircraft and more vulnerable to damage.
Conversely, 5.8 GHz signals are more easily blocked by intervening objects, but the antennas are much, much smaller and easier to install.
STEP FOUR: Transmitter/Receiver and Antenna
If you want to fly FPV, you’ll need a video transmitter onboard your aircraft to send live video, and a video receiver on the ground to pick up those signals. Wireless video systems aren’t standard equipment at most hobby stores, so you’ll probably have to look online to find one.
After you’ve identified a vendor, you’ll find that transmitters on your chosen frequency are available at a variety of different output levels, generally ranging from 100 milliwatt to 2 watts. It’s tempting to drop the most powerful one in your shopping cart and click buy; however, a good-quality antenna will actually have a much larger impact on signal quality than a high-powered transmitter.
Antenna quality is reflected in its gain (dB), and every three points of gain is equal to doubling the power of your transmitter. In other words, if you pair a 500-milliwatt transmitter with a 9 dB antenna, it will perform as though you have a 2-watt transmitter—at a fraction of the cost and the power draw on your battery.
Available online from specialty retailers, these circular, polarized receiver antennas provide great omnidirectional performance, which has made them popular among FPV pilots. As the wavelength of the signal being received decreases, the antennas shrink substantially, from the 1.3 GHz antenna at the top of the photo to the 5.8 GHz one on the lower left. A quarter is included for scale.
STEP FIVE: Choosing a Camera
When it comes to selecting a camera, you have a clear choice: a small, inexpensive, lightweight board camera or a heavier, more expensive sports camera such as the GoPro Hero series. Board cameras, which take their name from the fact that they resemble a lens attached to a circuit board, are typically powered directly from the main flight battery. They have no built-in capability to record the images that they capture.
Some sports cameras, such as the GoPro, have the ability to pass through live images as well as record high-definition (HD) video, which gives you the ability to relive your aerial adventures after the aircraft is back on the ground. A drawback is that these sports cameras are powered by their own internal batteries, which could run out of juice before your flight battery and leave you flying blind.
Many FPV pilots opt for both, wiring a board camera to their video transmitter and carrying a GoPro to record HD video without connecting it to their FPV systems. At Roswell Flight Test Crew, our practice is to use a video switch onboard our aircraft, so that we can switch back and forth between cameras while in flight.
Two frequent options for FPV cameras: a GoPro Hero on the right, which can send a live signal while simultaneously recording HD video; and, on the left, a lightweight, inexpensive board camera with interchangeable lenses to customize the field of view.
STEP SIX: On-Screen Display
This step isn’t mandatory, but it is a really good idea. An On-Screen Display (OSD) puts an overlay of aircraft telemetry on top of your video image. The most sophisticated OSDs resemble the Heads-Up Display on a modern jet fighter, with animated ladders that represent altitude, airspeed, direction, distance to home, and even an artificial horizon.
The most crucial piece of information that any OSD worth having onboard your aircraft can provide is your flight battery’s voltage. It’s easy to get caught up in the experience when you’re flying FPV, so it’s nice to have a reminder that your battery level is dropping, prompting you to complete the flight.
A sophisticated OSD can cost hundreds of dollars and include its own independent GPS receivers as well as a suite of sensors to directly measure altitude, airspeed, motor temperature, and g-forces. However, a simple OSD that only displays battery voltage can be purchased for less than $20.
This OSD provides the pilot with aircraft telemetry overlaid on top of the FPV video, including battery voltage, airspeed, altitude, compass heading, distance and direction to home, and latitude and longitude coordinates. It can even accept input from additional sensors to measure motor and ESC temperatures, g-forces, and other flight parameters.
STEP SEVEN: Choose Goggles or a Video Screen
Now that you have video and telemetry streaming live from your aircraft, you’re going to want to see it. There are basically two options available: video goggles or a small, battery-powered screen.
Goggles provide a much more immersive experience, putting you onboard your aircraft without any outside distractions. It can help novice pilots avoid becoming disoriented, because there is no temptation to look up at the aircraft itself and potentially become confused about whether it is coming or going.
Using a screen allows other people to watch the flight progress over your shoulder. This is a popular choice for aerial photographers who need to frame their shots while simultaneously keeping an eye on their aircraft as it moves through the environment.
Video goggles such as these Fat Shark Dominators, made specifically for FPV flying, are a popular choice because they provide an immersive experience by eliminating outside distractions from the pilot’s field of view.
A small video screen is one option for receiving the real-time FPV feed from your aircraft. It allows other people to share your aerial adventures by watching over your shoulder, and is a popular choice for aerial photographers. Be sure to get one that will display static rather than a “blue screen” in the event that you experience a partial signal loss—a broken-up image is preferable to none at all.
STEP EIGHT: Find a Friend
As described in Document 550, available on the AMA website, FPV flying is a team sport. There need to be at least two qualified pilots on the ground while the aircraft is in the air: the pilot, who is operating the aircraft via the FPV system, and the spotter, whose job is to alert the pilot to unseen hazards and be ready to take control of the aircraft in case of an FPV system failure.
After the goggles are on, the spotter has a critical role to play in maintaining the pilot’s situational awareness. Although the pilot can see what lies directly ahead, he or she may not detect a hazard off to one side or behind, or when there is a risk of putting an obstruction between the pilot and the aircraft. The wide field-of-view lenses typically used for FPV can make it difficult to spot small, but potentially show-stopping obstacles such as a bare tree branch or a power line.
Safe FPV flight operations require a minimum of two people on the ground: the pilot (R), who controls the aircraft and monitors the live video feed from the aircraft, and the spotter, who advises the pilot regarding unseen hazards and can take over control if the FPV system fails completely.
When conducted within the guidelines established by the AMA, flying FPV is as safe as conventional model aviation. It’s also a tremendous amount of fun, and becoming involved will put you at the forefront of revolution that will ultimately change the world.
In the years ahead, unmanned aircraft that are indistinguishable in their basic functions from the systems that hobbyists are using today will help first responders save lives, give farmers the ability to increase crop yields, and perform thousands of other functions, most of which haven’t yet been imagined.
It’s going to be an exciting couple of decades. Build yourself a system and come be part of it!
Roswell Flight Test Crew
Amateur Radio Relay Network
AMA Document 550
- See more at: http://www.modelaviation.com/FPVforBeginners#sthash.8MEqhZ2W.dpuf