You’re asking about the legal drone speed limit according to the FAA, right? That would be 100 mph. Of course, we’ll not stop at legal info, let’s explore how a drone flies, what barriers there are to speed and what you can do to fly faster.
Join us for another in our Science of Flight series, learning some of what makes a drone operate. Our goal is to help you understand how to fly, expanding your knowledge and improving your experience in the air.
What’s a drone?
First, we have to establish some ground rules. Well, not really ground rules, just, rules as to what we’re talking about here today. We’ve gone in-depth to explore what makes a drone a drone, while different styles of craft have entirely different science behind their movement, we will be talking mostly about quadcopters here today.
A fixed wing craft flies like an airplane, essentially, so we’ll focus on machines that have upward facing rotors instead.
How fast can a drone go?
Before we get into the actual science behind it all, I wanted to share some typical drone speeds with you. One of our favorite machines, the DJI Mavic Pro, can scoot along at about 41 mph at full throttle. Take it out of sport mode, ensuring stabilized flight and smooth video recording, and that drops down into the 30 mph range. But, just like your car, you don’t always fly around at full speed. My flight records indicate my moving average speed of my Mavic is about 11 mph, but I spend almost half of my time at a hover, that’s what drone photography is all about, especially for panoramas.
The Mavic Pro, even at 30 mph, is pretty fast compared to the average out there. In my experience, the average toy-class machine may get up to 12 mph, not very fast. Most of the drones you’d find on our under $1000 list and in our camera drones list have similar speeds to the Mavic Pro. Moving up the scale, you have something like the DJI Inspire 2 clocking in at just under 60 mph.
Commercial drones have some higher speeds, but for you and I at home, racing drones are where it’s at if you have the need for speed. Your average machine is still only going to clock in at 50 – 70 mph, but some of the top racing quads can break that 100 mph mark. The fastest I’ve heard of is 129 mph, a little rig based on the Stigg frame in our Best racing drones list.
Safety and legal
I’m going to pretend for a moment that you do not know all of the legal of drone flight. So, here are some rules that the FAA has in place for drones, including, even though it’s not front and center, a 100 mph speed limit.
It’s all about gravity
It feels silly to say that flying a drone at speed is all about gravity, you already know this, but I’ll say it for one reason, fighting gravity is the reason drones go so slow.
An airplane at speed is suspended in the air by its wings. That is, air force on the wings provides the lift. In a multi-rotor type drone, lift is provided by the propellers.
On that airplane, a propeller or jet is used to move the craft horizontally, providing speed. In a quadcopter, the propellers are still facing up, still fighting gravity to prevent a fall. I say again, the default action of a plane is to move, the default action of a quadcopter is to hover.
To move, your drone needs to tip sideways. The propellers are now providing thrust in a direction that both keeps the drone suspended and moves it through the air. The faster you want to go, the more the drone tips, but if you tip the drone completely sideways, for maximum movement energy, it will drop out of the air for lack of upward force. Gravity wins.
Drone flight is a delicate balance of thrust direction.
If you are flying for pay, or any other form of compensation, you must operate under a different set of rules and possess a commercial drone license. We call it the Part 107, it’s not too hard to get, but it will take some time to learn all the rules. We want to help you learn the rules and get your commercial license, check out our drone pilot training material.
How can I go faster?
Your camera based drone is a well balanced machine, and probably fairly symmetrical in design. Racing drones are not symmetrical, and this is why they can go faster. The idea for more speed is simple, if you can find a way to increase horizontal thrust without reducing the minimum upward thrust to stay in the sky, you’ll go faster.
The basic concept for a racing drone is to elevate the trailing propellers, or lower the leading ones. This little bit, perhaps with a little tilt forward, throws the drone out of balance for a stable hover. The tilt of the drone creates a forward moving attitude, helping the drone fly faster.
But wait, offsetting the propellers doesn’t affect the gravitational forces. Good catch, you are correct, raising the rear props and twisting both sets forward does not change the fact that too much drone tilt still drops out of the sky. This is where speed and the body of the drone make a difference.
Your basic drone tilted sideways provides a very non-aerodynamic leading edge. A racing drone, on the other hand, points into the wind a little better at speed. Many designs even form the propeller arms to act as little wings – every bit of lift helps.
Fancy drones have articulating propellers, so that the body of the craft remains completely level no matter what stage of flight.
Changing propellers is one of the easiest ways to improve speed. Same for motors. Basically, more power equals more speed. That’s easy to understand. Propellers come in many shapes and sizes, be sure to hit our Drone propellers article in this Science of Flight series for more details.
Final thought, please hit the comments below if you’d like to learn about flight techniques for flying faster. For now, I’ll assume you understand that flying in a straight line will be much faster than when turning sharp corners.
Some top speeds
DJI Mavic Air – 42.5 mph
DJI Mavic Pro – 40 mph
DJI Phantom 4 Pro – 45 mph
DJI Inspire 2 – 58 mph
Uvify OOri – 50 mph+
Stigg racing drone – 129 mph+
These are all “official” numbers, real world performance will differ. Let us know if there are any other drones you’d like the registered top speed for, we’ll get it on this little list.
Without getting creative, perhaps adding an additional forward facing propeller to your craft, your speed is completely determined by how well your drone can stay in the air. Fighting gravity is the hardest part for these machines. Tilting a craft sideways provides the thrust for movement, tilt too far and you lose the fight against gravity.
Most drones out there have limiters in place, the flight controllers prevent you from tilting too far. This can be very handy with the stock gear, but if you upgrade motors or propellers, all of a sudden those safety limits can’t keep up with your new flight. Again, it’s all a balancing act.
Have you had the need for speed – how fast does your drone fly?