Before the use of drones, an aircraft or helicopter was used to obtain aerial imaging, this was expensive, not very useful, (because of the speed of the aircraft), did not always capture the angle or detail required, unsafe, (because the aircraft would have to slow or conduct maneuvers which could be dangerous), and was time-consuming to organize.
The AAIA realized that the use of drone technology was significantly less expensive and could provide aerial images within minutes of arriving at an accident site. Drones were also able to capture and document the debris field and locate components or parts strewn about as a result of the impact sequence.
Samples of debris field captured since the introduction of drones to the AAIA arsenal follows:
The drones used with their varying megapixel cameras provide excellent stills and video quality. As well as taking stable video, the additional benefit of the drones used is that the cameras could be tilted 90 degrees downwards to take a series of overlapping images to map the whole accident site.
With the added use of software such as photo-stitching, images can be stitched together providing a much greater view of the area of the accident. Other software such as photogrammetry could generate 3D models from a series of overlapping images, that was true to scale and creating imagery such as orthomosaics. The various software used with the aid of imagery captured by the drones helps the investigator analyze and have a much better understanding of the accident sequence of events up to the point of final stop.
One of the greatest benefits of drones for the AAIA is for overhead views photo documentation of accident sites that may be inaccessible or dangerous for investigators, such as in waters and when fire or other potential dangers are present at the accident site.
Benefits of drones for accident site imagery
The main benefits of using drones over manned airplanes or helicopters are:
● Significantly lower cost (a suitable drone can be obtained for about $800).
● Drones can be deployed immediately on arrival at the site.
● The images and video from the drone can be viewed live on the ground.
● The investigator has full control over the images and videos that are taken.
● A drone can be easily relaunched to take additional footage.
● A drone can be flown close to trees and wreckage to obtain close-up images without disturbing them with rotor downwash.
● A drone can be easily programmed to take a series of geo-tagged and overlapping overhead shots for photogrammetry purposes.
● A drone can operate in low-visibility and low-cloud conditions that would prevent an airplane or helicopter from being operated.
The uses so far identified for drones at accident sites are:
● Wreckage and site survey,
● Wreckage search,
● Tree/object height estimations,
● Site safety assessments, and
● Flightpath reconstruction/visualization.
Also, with the introduction of underwater drones, underwater debris fields can be more accurately documented. The time it takes for divers to physically photograph a debris field, the drone can accomplish this in a much shorter time and in a safer environment without the need to constantly resurface or the concern for underwater creatures that may pose a threat to the unsuspecting divers.
Benefits of Using Drones at Aircraft Accident Sites
With the creation of the Aircraft Accident Investigation Authority (AAIA) to investigate aviation accidents and incidents in the Bahamas, one of the latest investigative tools in our arsenal, is the introduction of technology by way of drones to provide aerial images of accident sites.
The AAIA recently signed a memorandum of understanding with FlyyTec Ltd for the use of its drone technology to assist in the aerial documentation of aircraft accidents and incidents sites. The use of drones are essential for a number of reasons.
They can capture the whole site from the initial impact point to the aircraft or wreckage’s final resting location.
The ground marks and wreckage distribution help to identify how the aircraft hit the ground.
Aerial images are also useful for showing the relative positions of obstacles, such as trees or buildings that may have been struck before ground impact.
They help to reveal the surrounding terrain and environment that the pilot faced if there was an attempted forced landing.
And when it’s a large aircraft at an accident site, aerial images help to document the damage to its upper surfaces.