NASA’s Ingenuity helicopter sent its final signals to Earth in the earlier part of the year. Engineers have been studying these and have started to piece together a picture of events that led up to its final flight. They concluded that data provided by the navigation system was inaccurate leading to a chain of events that caused its ultimate demise. One of the biggest problems it seems is that the terrain was smooth leading to a lack of landmarks during Flight 72.
Mars is the fourth planet from the Sun and is well known for its distinctive red colour. It’s surface is is covered in iron-oxide which is known by the more common name – rust. The planet is just over half the size of the Earth and has some fascinating geological features like Olympus Mons, the largest volcano in the Solar System. Valles Marineris is a canyon system which stretches thousands of kilometres and dwarfs the Grand Canyon. The atmosphere of the planet is mostly composed of carbon dioxide and currently incapable of supporting life. It’s not thought this has not always been the case and its missions like Mars 2020 that have helped to unravel the mysteries of the red planet.
The Perseverance Rover and Ingenuity helicopter were both part of the Mars 2020 mission and have been exploring Mars since their launch in 2020 atop an Atlas V rocket. Ingenuity became the first robotic rotorcraft that undertook powered flight in the Martian atmosphere. The inaugural flight took place on 19 April 2021 the 1.8 kilogram drone took off under the power of two counter-rotating blades. The blades of the drone are 1.2m long, oversized by Earth standards but the atmosphere is only 1% as dense as Earth so larger than usual blades are needed.
Flight 72 was scheduled for the 18th January this year and there was nothing special about it. The plan was a brief vertical hop to checkout the flight systems and to grab some photographs of the area. The flight data revealed it reached an altitude of 12 metres, took the images and was back on the surface after 32 seconds but had severed communications. After communications was re-established, it was discovered that Ingenuity had sustained damage to its rotors.
Now, almost a year after the incident, a team of engineers from NASA’s Jet Propulsion Laboratory have been analysing the data. Their findings will be published in the next few weeks however the team of engineers assert it was harder than expected to complete an accident investigation from 160 million kilometres. The faults lie in the navigation system that was designed to visually track surface features using a camera pointed at the round. The system worked during early flights over more textured terrain but as Ingenuity moved over the Jezero Crater, it began operating over featureless sand ripples.
The navigation system was designed to provide estimates of the helicopter’s velocity, chiefly to enable it to land. The data revealed from Flight 72 revealed that the navigation system couldn’t find features to track. Images showed that the lack of features led to a harden than usual touchdown leading to a pitch and roll of the craft. The sudden change of attitude led to increase load on the rotors, beyond their designed limits leading to the structural damage.
Even though Ingenuity will not be able to fly anymore it can still provide weather and avionics data to the Perseverance rover. It will help us to understand more about the weather in its vicinity but perhaps its greatest legacy are its hours of flight on an alien world.
Source : NASA Performs First Aircraft Accident Investigation on Another World