Do you want to learn more about drones, UAV technology and areas of application for UAS? Here you can find answers to frequently asked questions.

Do I need a permit to fly a drone?

In Germany a so-called Ascent Permit (Aufstiegsgenehmigung) is required for commercial use of unmanned microcopters (drone). This is issued either individually or generally by the respective states and is valid for several years. We have compiled all the necessary information and local contacts for our customers to easily obtain the permit, and will be provided to you after purchasing a Height-Tech multicopter.

Why don’t you sell helicopters?

We invariably sell multi-rotor systems, i.e. drones with multiple propulsion systems and the least possible mechanical systems. Since these aircraft are stabilised by an electronic system, this eliminates the complex and fault-prone helicopter system or stabilisation system (paddle level). Eliminating these complex mechanics makes our drones virtually entirely maintenance-free. Another great advantage of our drones is the use of many relatively small motors and propellers as opposed to one large main rotor. These small, yet very light propellers keep the risk of injuries very low. There have unfortunately been some very serious accidents involving conventional helicopters this size.

Why are there drones (UAVs) with 4, 6 or even 8 motors?

A drone needs a minimum of 4 motors to be able to fly without any additional mechanical systems (angle of approach adjustments for the motors). Two of those motors rotate clockwise, two counter-clockwise. This cancels out the torsional moment, eliminating the need for an inefficient tail rotor as on a helicopter.

The disadvantage of a drone with 4 motors is the lack of back-up in the event of motor failure. If a motor fails on this so-called quadrocopter, as unlikely as this may be, the drone will crash. In order to compensate a motor failure, more than 4 motors are used, so 6 or 8. In a drone with 6 motors, a so-called hexacopter, a motor can fail and an emergency landing undertaken. However, if the motor fails in an adverse flight state or on a heavily loaded drone, a crash will also occur here. This is why for our most powerful system we chose eight propulsions (octocopter). This system offers maximum failure back-up with excellent efficiency.

How much can a drone carry?

The net load of our strongest drone is currently up to 2,400 g. This includes the weight of the respective camera mount. We generally recommend keeping the net load as low as possible to be able to reach long flight times when needed. For example, current system cameras can achieve close to the video quality of full format cameras, even surpassing them, with only 50% of its weight.

Drones can also easily be designed for significantly higher net loads, simply contact us.

How long will a Height-Tech drone fly?

The flight time for our drones is generally between 5 and 40 minutes.

The flight time depends on four factors:

– Batteries

– Flight task

– Wind velocity

– Net load weight

If the net load needed is low, the weight reduction can be invested in batteries with higher capacity, thus longer flight time.

Multi-rotor drones are most efficient whilst hovering or at low flight speeds. If, for example, during the filming of a car chase a high flight speed is required, the power used will increase greatly, reducing the flight time. In winds the behaviour will be similar to high flight speeds. To stop in a position the drone will tilt toward the wind (wind correction angle) to compensate wind with high thrust performance. The stronger the wind, the higher the compensation required and the lower the flight time. The net load carried is also very relevant to the flight time. The flight time e.g. using a Canon 5D Mark II (1.2 kg) compared to a light live camera (100g) is nearly cut in half!

How high and far can drones fly?

The range of the drone control is about 1.5 km. Export systems can achieve a range of up to 50 km. The range is limited due to the mandatory (in Germany) visual contact between the pilot and the aircraft. In the field our larger drones can therefore operate at a perimeter and altitude of about 200m. When using the drone in the mountains the limits are set by the low atmospheric pressure and low temperatures. However, our drones have already been successfully used at 3,950 m above sea level and in temperatures of -15 °C.

Which sensors do you use to stabilise the drone?

We typically rely on the sensor data fusion of rotational speed-, acceleration-, compass-, barometric pressure- and one GPS sensor. The rotational speed- and acceleration sensors are used to determine the position of the aircraft in an area. A compass sensor is needed in order to correctly convert the GPS position data to capture the “line of vision” of the aircraft. The barometric pressure sensor is needed to accurately position the drone on the Z-axis (Altitude Hold). Using the consolidated position data and the GPS position data the drone can determine and maintain the X- and Y-axis (Position-Hold). In addition to the sensors they also require a number of micro-controllers, up to 10 depending on the drone, with various tasks.

Which cameras can be used?

Our systems will currently carry the following cameras:

Panasonic Lumix GH-2
Panasonic Lumix GF-1
Panasonic Lumix GF-2
GoPro HD
Ricoh GX 200
Canon 550D
Canon 5d Mark II
GoPro Hero 3
Sony NEX-7
Panasonic G3
Optris PI400/450
Canon 5D MK III
Optris PI400/450 + Panasonic GH3 (simultaneously)
Nikon D5200
Nikon D800
Panasonic GH3
Sony Alpha 7
Sony PJ 780
Optris PI400/450
Panasonic GH3

Of course we will gladly adapt your preferred camera for use with our drones. The camera weight incl. camera mount, however, mustn’t exceed the maximum net load. The interface for remote release (infrared or USB) and, if applicable, analogue video output for the live downlink on the camera to be used are important.

Which drive technology do you use?

Our drones are propelled by electricity. We use state-of-the-art external rotor motors which change their speed several hundred times a second. Using external rotor motors allows for propellers to be directly propelled without a loud and heavy drive. These propellers with low speeds are required for the high efficiency of the overall system. We use the latest lithium polymer battery technology to guarantee the best possible power to weight ratio.

The construction of these batteries is comparable with batteries for mobile or laptops (LiIon), however have a greater current rating.

What happens if my drone crashes?

After sending the drone to use we will review the data of the flight data recorder. This allows us to determine the cause of the crash (if unclear). We will simultaneously create a damage analysis and an estimate (if the crash or damage was caused by you). The damage will then be repaired as quickly as possible. Since we typically have all spare parts in stock, your drone will usually be returned within a few days. If you ordered the “First Class Package” (see “Service”), you will promptly receive a replacement drone free of charge and will immediately be able to continue working.

What makes your drones so unique?

The high degree of development in-the-field is the greatest advantage of our drones. Our head of development and President, Joseph Metz, has many years and more than a hundred flight jobs of experience in the commercial use of drones developed in-house. His jobs have taken him to many countries throughout the world where drones were used under the most adverse conditions. This know-how influenced the development of our robust drones suitable for daily use.

In addition, we will not leave you out in the rain after purchasing one of our drones. We developed a concept for you to gradually learn the safe use of our drones. Another service offered is our support in obtaining the necessary ascent permits.

See what our drones have to offer.

What does the drone do if the radio link fails?

If the control signals from the remote control fail, the drone will stop in its current position, and after a few seconds will start its descent. This emergency landing scenario continues until the radio link is re-established or the drone has landed. For export systems we also have the option to have the drone automatically return to the launch site to land if the radio link fails.

Are the aircraft easy to fly?

We feel it is very important even for customers without model flight experience to be able to control our drones. Our drones feature a number of stabilising sensors so the pilot can focus on the actual task, e.g. aerial photography.

It’s helpful to be able to fly a drone manually without stabilisation aids in order to exhaust its maximum capabilities. We therefore offer extensive flight training to each customer, virtually as well as with a robust practice drone.

To date each of our customers learned how to handle their drone from us. So can you.

Do I need to shoot “blind”, or how do I recognise the right perspective?

Of course the camera’s viewfinder image is transmitted to you on the ground in real time.

This uses an analogue video link. You can either view the viewfinder image on a monitor or modern video glasses, allowing you to easily and quickly select the right perspective.

Do I need to insure my drone, or will my public liability insurance suffice?

Commercial use of drones requires a special aircraft liability insurance. This will insure you against damage to other valuables or persons. The insurance premium varies from 170 and 1,600 EUR annually depending on the insurance company, with the amount insured ranging from 1.5 – 3 MM EUR.

Can flying robots also perform tasks other than capturing aerial photos or aerial film?

Of course the applications go far beyond these. For example, we have already created 3D maps and charts using our drones, which allows for e.g. the volume of a lignite opencast mine to be calculated. There are also options for using thermal imaging- or near-infrared cameras. This allows for faults in solar panels or the water shortage of plants to be detected from the air. If you own a special sensor technology system we will adapt it to our drones (or our drone to your system) and put it in the air.

Can drones also be used indoors?

The emission-free and silent electric drives of course also allow our drones to be used indoors. Applications are e.g. demo flights at trade fairs or film shots inside buildings. Due to the typically limited space a suitable launch and landing site not accessible by onlookers must be provided. Since the GPS and compass sensor technology is typically extremely limited inside buildings, the pilot must be able to control the drone manually.

Can the drone batteries also be charged on the road, without outlets?

Of course our chargers can also be used in the car (12V) via the cigarette lighter. This requires your car battery to be in good condition. For extreme applications with frequent charging cycles on the road, you also have the option to charge via solar panel. Depending on the mission profile of the drone we will of course also provide you with a custom solution as usual.

I need to travel by plane with the aircraft, will this cause problems with the airlines?

The drone is typically checked in as luggage inside the transport case. To date there have not been issues with airport security with the exception of some enquiries and a smear test (testing for residues of explosives). The batteries should be placed in the carry-on luggage, wherein some airlines have restrictions with respect to the number and size of batteries. Therefore please contact your airline to determine if you will encounter problems.

Are there restrictions or prohibitions in operating the drone?

In Germany, an operator of a drone partakes in air traffic and must also comply with the regulations of the Air Traffic Act and Air Traffic Order. Luckily, Germany has few restrictions for using drones with a take-off weight of up to 25 kg.

For example, a minimum distance of 1.5 km from airports must be maintained, and there are a few no-fly zones (e.g. Berlin government district). We will instruct you on all the pertinent areas of the air regulations and you will then be able to legally and safely pursue your business.

Am I allowed to drop flyers or the like with my drone?

Dropping objects other than ballast (water, sand) requires an ascent permit from the respective Luftfahrtbundesamt (Air Traffic Order § 7.1). An ascent permit is typically very easy to obtain for objects which do not pose a risk of injury (e.g. rose petals).