Article updated on 26 August 2021
Image Credit: aapsky/Shutterstock.com
The landing phase is the most intensive stage of an aircraft’s flight. According to Szondy (2021), up to 40% of crashes occur during this phase. This is likely due to the method of landing, in which pilots use visual cues and peripheral vision to judge their landing. These cues can be inaccurate or hard to see in situations of poor visibility. AirText, a company already versed in aircraft hardware, is using its new product, Land-DAR, to make this phase simpler and safer for small aircraft.
The Standard Methods of Landing an Aircraft
During the approach and landing phase of flight, visual cues tend to be the most common and most useful tool when landing an aircraft. It allows the pilot to keep his focus on the environment while still having a good understanding of height and distance of the craft. Being too dependent on modules such as the altimeter and over observing the aircraft’s path can be dangerous and distracting to the pilot.
To do this, pilots usually visualize a reference height and an aiming point on the runway. While descending, the pilot tries to keep these two points level with each other to establish proper pitch altitude. Whilst doing this, the pilot must also adjust power and elevator control accordingly to maintain pitch and airspeed. They must also maintain a centerline with the runway against crosswinds with aileron control.
Doing all this allows the pilot to determine when to flare the aircraft. ‘Flaring’ is the act of increasing the pitch of the plane, so the nose is pointing slightly upwards before the wheels touch the runway. This action lowers the speed of the aircraft, creating a more comfortable landing. It also allows the rear wheels, which can withstand more force, take the initial brunt of the aircraft’s weight, rather than the front wheels. If done too late, the front wheel can buckle under the weight, causing the aircraft’s nose to crash into the runway.
Doing all this, while trying to maintain a constant airspeed, angle of descent, and speed of descent is very intensive and requires a lot of attention. Even then, this landing model is for ideal circumstances. The difficulty of landing is increased even further in situations with high sidewinds, or small runways.
More specifically, landing an aircraft can become much more difficult with low visibility. Any issues that disrupt visual cues or cause the pilot to question the validity of the cues (such as parallax discrepancies caused by “narrow runways” (Airtext, 2021), unfamiliar environments around the runway, etc.) are problematic.
Commercial and military aircraft are well-equipped to deal with these conditions. Small aircraft, however, do not have the same capabilities and modules. Airtext, a manufacturing company most known for its passenger communication avionic hardware, believes its new technology, the Land-DAR, can change this for small aircraft.
Land-DAR and LiDAR
The Land-Dar is a piece of hardware intended for small aircraft to aid pilots during the landing phase of their flight. The product accurately detects the altitude of the aircraft up to 100 times a second. The speed and accuracy are achieved using Light Detection and Ranging (LiDAR) technology.
LiDAR is not a new technology to the aeronautical industry and is used largely in military aircraft. The premise of LiDAR is to send continuous pulses of light via a laser to the ground and then using a sensor to detect this light. This data is then used to determine distance from the target and the sensor.
The method of data collection - how it is used to calculate distance - is simple to understand. Once the light from the laser hits the ground (or anything below such as buildings and trees), it reflects to the sensor. This allows the system to determine the time taken from laser emission to sensor detection.
Using this time and the speed of the laser emission (the speed of light) can then be used to calculate the distance that the light has traveled. Halving this distance gives the aircraft’s elevation. The distance is halved as the light beam traveled the elevation twice (from the laser to the ground, then back from the ground to the sensor).
If the laser emissions are continuous enough, a LiDAR system can create an accurate 3D map of the terrain underneath the aircraft.
Applications of Land-DAR and How it Makes Landing Safer
Land-DAR is a combination of LiDAR technology and a smartphone app. The LiDAR module is installed under the aircraft and sends the data to the user’s smartphone during the landing phase, giving the app up to 100 elevation data points every second. During the landing phase when the Land-DAR is activated, the app will then communicate various points of elevation (200 ft, 100 ft, and then in steps of every 10 ft, starting at 50 ft).
The main benefit of this device is that it, essentially, takes out the subjectivity aspect of visual cues, without distracting the pilot from watching the plane’s descent. The scientific data collected is consistent and accurate, as LiDAR technology is very precise.
The constant update of elevation through the speaker is also beneficial, as it not only establishes the height of the aircraft, but also the speed at which it is descending. Pilots aim to keep the rate of descent of an aircraft constant. The time between Land-DAR’s announcements can be used to confirm a consistent descent speed.
Land-DAR is relatively cheap and easy to install, meaning small private aircraft that do not possess the same capabilities as their commercial aircrafts can install and use them simply. For this reason, alongside the fact that most aircraft crash during the landing phase of flight, the private aircraft industry is likely the best demographic for the Land-DAR.
With this new product, pilots of small aircraft have a new method of determining both distance, altitude, and descent speed without sacrificing any time away from observing the descent and visual cues. This gives the pilot a much clearer idea of when to slow the craft, change the pitch (during approach), and even a good indicator of when to flare the plane before touchdown.
If used on a wide scale, the Land-DAR has the potential to prevent many aircraft crashes and could make what is usually the most daunting phase of flight much safer and simpler for pilots.
References and Further Reading
Goairtext.com (2021). Land-DAR. [online] Available at: https://goairtext.com/land-dar/ (Accessed 24 May 2021)
AirText (2021). Airtext – Airtext lets aircraft owners add reliable in-flight text messaging and more for passengers. [online] Available at: https://goairtext.com/ (Accessed 20 May 2021).
Szondy, D. (2021). Land-DAR uses lasers to improve safety of small plane landings. [online] New Atlas. Available at: https://newatlas.com/aircraft/land-dar-lasers-help-small-plane-pilots-land-safe/ (Accessed 24 May 2021).
Aviation Stack Exchange (2014). How precise are altimeters? [online] Available at: https://aviation.stackexchange.com/questions/3727/how-precise-are-altimeters (Accessed 25 May 2021).
GeoSLAM. (n.d). What is LiDAR and How Does it Work? [online] Available at: https://geoslam.com/what-is-lidar/ (Accessed 22 May 2021).
ERAU SpecialVFR (2017) Normal & Crosswind Approach & Landing - Lesson 1. Youtube [online] Available at: https://www.youtube.com/watch?v=DxbcyBjFiSg (Accessed 22 May 2021).