The mountain of info available on unmanned aerial vehicles (UAVs) can be daunting. Don’t despair – ALTI has you covered with the basic things you need to know about vertical take-off and landing aircraft. Read More
While drones in a military or intelligence context is nothing new, more and more people, businesses and industries are exploring ways to make use of VTOL UAVs as part of the day-to-day strategy of their business.
However, you’ll probably agree that you can’t invest in something if you don’t even know the basics… We have compiled a list of 7 “first things first” points that you should know about UAVs before you buy one.
VTOL stands for Vertical Take-Off and Landing. VTOL aircraft can hover, take-off and land almost to the surface they’re standing on, without needing a lot of space – much like a helicopter. Quite straight-forward, isn’t it?
It means that the aircraft doesn’t need a runway or any additional launching or landing equipment, such as catapults or parachutes.
The first VTOL aircraft in operation was a which took to the skies in August 1966.
VTOL itself is therefore nothing new, but the technology has rapidly advanced since then.
VTOL UAVs use rotors to lift them into the air, to hover and to land. For take-off, the spin of the rotors create a downward push of air, working against the earth’s gravitational power to lift the aircraft off the ground. It then transitions from using the rotors to using the push motor for propulsion and the wings for lift.
During flight, the aerodynamic shape of the wings direct airflow over the surface of the wings, keeping the aircraft aloft (just like an aeroplane). When the UAV needs to land, a transition back to the rotors takes place. The aircraft hovers while the rotors’ speed is gradually decreased – just enough to brake the aircraft against the power of gravity as it lands, to prevent it from dropping out of thin air.
The rotors and push engine are powered by a rechargeable battery pack, which also supplies power to everything else on the aircraft.
At the helm of it all is the VTOL UAV pilot. Flight is controlled using a ground control system. With ALTI’s UAV fleet, this advanced system is called the ALTI C2 command and control station. It was developed specifically for ALTI aircraft and consists of, among other things, two large HD displays, video and control links, and mission planning and control software, all held together in a compact and sturdy Pelican case.
As with manned VTOL aircraft such as helicopters and gyrocopters, there are different types of unmanned VTOL aircraft. We’re focusing on the three main types.
These are the entry-level drones and also the most common type of UAV. It uses several (most often four) rotors for lift and propulsion. However, needing the rotors for propulsion makes them quite energy-inefficient.
Fixed-wing aircraft fly more efficiently than multicopters, because they provide lift like a normal aeroplane by means of wings, not rotors. Using wings for lift means they only require energy to move forward, not to stay in the air. It also increases their capability to fly for longer – this is called endurance.
One of the downsides to a fixed-wing aircraft is that it needs a large and relatively smooth landing space, free of obstructions like rocks or snow.
A VTOL hybrid aircraft is a combination of multicopters and fixed-wing aircraft as mentioned above. The wings serve a dual purpose: to provide lift as well as stability during flight.
Because of the larger surface area of the wings, the job of propelling the aircraft is shifted away from the rotors and onto the wings. This increases the flying time or endurance and also lends greater stability while it’s in the air. The advantage of VTOL hybrids is that no runway, launch equipment or pilot are required for take-off and land, making it easy and safe to manoeuvre almost anywhere.
With a low running cost of as low as $3.50 USD it is no wonder that more and more industries prefer using drones for surveillance, inspections, mapping and photogrammetry. Consider the cost of a drone, the power and time needed for one battery charge, and the time it takes to get the job done, and compare it to the cost of hiring an aeroplane or helicopter, a pilot, equipment and again, how long it takes to do the work. It’s a no-brainer that a drone wins this race hands-down.
Surveillance of large areas can therefore be done at a much lower running cost than if a fixed-wing aircraft is used, because the company saves on additional expenses such as aircraft rental fees, fuel, pilot fees and insurance.
Thanks to decreased liability during inspections, insurance could also be cheaper when using drones for inspections of dangerous sites such as mine shafts, oil rigs or the inside of grain silos.
VTOL drones are much quieter than helicopters and are already being used in anti-poaching operations in certain parts of Africa. These aircraft are also used in surveying of game parks and nature reserves.
Often armed with infrared cameras for night vision, these UAVs are proving their worth in the fight against poaching. Add to that a range of hundreds of kilometres in some drones and you have an invaluable addition to your anti-poaching team. With an endurance of over 6 hours and payload capabilities of 600 grams, the ALTI Ascend is a small yet extremely capable option.
During the global Covid-19 pandemic, the importance of having VTOL aircraft at one’s disposal became even clearer than before. Should a global pandemic strike again in future, human interaction can be limited even further by using VTOL drones for home deliveries of medication or even food parcels, minimising the risk of infection (or worse, physical harm).
In industries where routine inspections can be extremely dangerous, such as mining or oil and gas rigs, the use of drones minimises the safety risk to the person doing the inspection.
Because a VTOL aircraft lands on its “feet” rather than on its belly, any payload that it carries is by default more protected against damage from abrasion (dirt, snow, rocks) than it would’ve been if a fixed-wing aircraft was used for the same task.
On-demand flying taxi services have been the topic of many “in the future we will have that” conversations, but the future is here. Airbus showcased a prototype flying car at the 2017 Geneva air show. NASA has also developed a battery-powered VTOL aircraft that flies like a normal aeroplane but takes off and lands vertically.
ALTI has developed the world’s only ready-to-fly autopilot and avionics system for VTOL: the ALTI AvioX.