Space Sunday: a helicopter, a space station and a big ‘plane

April 25th (mission Sol 64), Ingenuity’s sideways looking colour camera just manages to image NASA’s Perseverance rover as it observes the helicopter’s 3rd flight from a distance of 85 metres from Ingenuity. The black disc in the lower left is one of the helicopter’s landing feet. Credit: NASA/JPL

NASA’s Ingenuity helicopter drone has now complete four of its five initial flights on Mars, and in doing so, NASA has announced the programme has moved from demonstration flights to an extended “operational” flight regime covering at least a further 30 days. In particular, Ingenuity will be used to test how future aerial drones might be used in support of ground-based operations, with Ingenuity working in partnership with Perseverance, the Mars 2020 rover, as the latter commences the operational phase of its own science mission.

For Ingenuity to now enter a new operational demonstration phase, our team has been extremely happy and proud. It’s like Ingenuity is graduating from the test demo phase to, now, the new demo phase, where we can show how rotorcraft can be used.

– MiMi Aung, Ingenuity Project Manager

During its third flight, which occurred on Sunday, April 25th (mission Sol 64) Ingenuity flew a total of 100 metres, again at an altitude of around 5 metres, lifting-of from “Wright Brothers Field” to travel 50 metres downrange before hovering briefly and then returning to “Wright Brothers Field” and making a safe landing.

Along the way, the helicopter achieved another first – capturing a shot of Perseverance from the air. When enlarged, the image of the rover was slightly grainy, but the helicopter was moving at speed and was some 85 metres from Perseverance, with the colour camera set to periodically take photos – given the Earth-Mars distance, it simply isn’t possible to aim the camera in real time during a flight.

A series of still images from the downward-facing camera on Ingenuity strung together to produce an animation of the helicopter’s shadow passing over the surface of Mars. NASA/JPL

The helicopter’s 4th flight had been planned for Thursday 29th at 14;12 UTC, but was cancelled when Ingenuity has a further timing issue of the kind that caused a postponement of its pre-flight checks in early April. Whilst adjustments were made to the helicopter’s software to correct the issue, the engineering team noted that there was potential for it to again occur.

However the fact that the issue had been encountered meant the team were prepared for the problem, and 24 hours later, Ingenuity lifted-off to cover a total distance of 266 metres – 133 downrange and 133 back to “Wright Brothers Field”, flying for a total of 117 seconds, – well in excess of the planned maximum flight time of 90 seconds, and reaching a horizontal speed of 13 km/h.

Images from the flight were still being received and processed at the time of writing this article, but it is hoped that Ingenuity may have again caught Perseverance in one the five 13 megapixel shots taken with its sideways-looking colour camera. It  is also hoped that the microphones aboard the rover, which were turned on during the flight, may have caught the sounds of Ingenuity flying.

The Mastcam Z system on NASA’s Perseverance rover captures an image of Ingenuity flying downrange from during its 4th flight on April 30th, 2021. NASA/JPL

The decision to extend Ingenuity’s mission beyond the initial 30 days came as something of surprise: prior to the 4th flight being delayed, NASA were still talking in terms of the flight regime ending after the initial 30 days.

However, a re-evaluation of Perseverance’s science programme brought about a change of heart.  The initial flight extension is for a further 30 days, with further extensions possible if the helicopter can continue to operate in partnership with the rover, rather than the latter being a passive observer. Theoretically, there are no limits to how long Ingenuity might operate: it has no limiting consumables, and the only real threats to its operation being a crash, a mechanical issue or a failure resulting from the thermal stresses imparted by the day / night temperatures extremes.

China launches First Space Station Element

At  03:23 GMT on April 29th, a heavy-lift Long March 5B booster lifted-off from China’s Wenchang Spacecraft Launch Site on the island of Hainan, carrying the core module of the nation’s long-awaited permanent space station into orbit.

The Long March 5B used to launch the Tianhe-1 core module of the Chinese space station rolls out to the launch pad at the Wenchang Spacecraft Launch Site on Hainan Island, April 23rd, 2021, ahead of its April 29th launch. Credit: STR/China News Service
The 22.6 tonne Tianhe-1 (“Harmony of the Heavens”), also known as the Crew Cabin Module, is a 3-section unit designed to provide living quarters for a planned crew of 3 tiakonauts (as Chinese astronauts are called), with the associated life support systems, a power, propulsion facility that will provide power, life support, control and guidance for the entire station, and a docking hub.

Overall, the Tiangong space station is expected to comprise Tianhe-1 and two additional modules, Wentian and  Mengtian. The latter will provide a mix of research and science capabilities, together with further navigation avionics, propulsion and orientation control systems. Once launched, they will bring the station to around 60 tonnes in mass, with the option of additional capabilities being provided by Tianzhou resupply vehicles.

An artist’s illustration of China’s space station in Earth orbit. The core Tianhe-1 module extends from the centre to lower right, with a Tianzhou automated cargo / resupply vehicle docked at the aft airlock. Upper left shows a Shenzhou crew vehicle docked at the forward docking hub airlock. lower left and upper right are the two science modules with their solar arrays extended. Credit: Adrian Mann/All About Space magazine/Future Plc

Tiangong builds on the experience China gained in operating two (relatively short-lived) orbital laboratories, Tiangong-1 and Tiangong-2.  Despite its small size when compared to the 460-tonne International Space Station, the Chinese station will have a powerful research capability: fourteen internal experiment racks and more than 50 external docking points for instruments designed to gather data in the space environment, with 100 experiments already earmarked for flight on the station.

The two additional modules will not be launched until 2022. Before then, Tianhe will be visited by a automated Tianzhou resupply vehicle in May 2021. This will be followed in in June 2021 by the first crewed flight to the station. Tianzhou and crewed missions will then continue alternately in September / October 2021 and April / May 2022, before the science modules are launched for automated rendezvous with Tianhe-1 in May or June 2021 and August or September 2022.

Among its duties, the station will help China prepare for its planned crewed missions to the Moon and also co-operate a Hubble-class space telescope China plans to launch in 2024. This will occupy an orbit in a similar inclination to the station, allowing it to be serviced by crews operating from the station.

In  the meantime, the booster used to launch Tianhe-1 has caused consternation as China has effectively abandoned the 30 metre long core in low Earth orbit, and it is expected to make an uncontrolled re-entry into Earth’s denser atmosphere some time in the next week. This is a cause for concern as the booster’s orbit carries it over population centres such as New York, Madrid, Beijing and Wellington, New Zealand, and there are elements such as the motors that could survive entry into the atmosphere and strike the ground.

This is not the first time China has taken a cavalier attitude towards large mass orbital debris coming back to Earth: both the Tiangong 1 and Tiangong 2 orbital laboratories were left to make uncontrolled re-entries into the atmosphere, risking potential ground impacts.

Blue Origin and Dynetics formally protest SpaceX Moon Lander Contract

As  I reported at the time (see: Space Sunday: to the Moon, ready to fly and pioneers), mid-April saw NASA surprisingly award SpaceX the sole contract for the development of the Human Landing System (HLS) that is intended to ferry crews two and from the surface of the Moon as part of the Artemis programme.

At the time of the announcement, three groups were in competition for the contract to develop HLS – SpaceX and teams lead by Blue Origin and Dynetics respectively, with NASA indicating at least two contracts would be awarded. However, the April announcement indicated that only SpaceX would receive a HLS contract, worth US $2.9 billion over the next several years, and that funding for other contracts could not go ahead due to “budgetary constraints”.

Now, the remaining two teams have filed complaints with the US Government Accountability Office (GAO), demanding the NASA decision be reviewed.

NASA has executed a flawed acquisition for the Human Landing System (HLS) program and moved the goalposts at the last minute. In NASA’s own words, it has made a ‘high risk’ selection. Their decision eliminates opportunities for competition, significantly narrows the supply base, and not only delays, but also endangers America’s return to the moon. Because of that, we’ve filed a protest with the GAO.

– Apart of a Blue Origin statement on the HLS contract

SpaceX was a relative latecomer to the HLS system, with both Blue Origin and Dynetics fairly well advanced with their designs, with the Dynetics design in particular offering an exceptionally flexible approach, able to be used as both a crewed lander and cargo delivery system – with the latter modules capable of being linked together to provide additional surface facilities / living space.

The three proposals for NASA’s Human Landing System vehicles that had been under consideration for the Artemis programme. Left: the Dynetics lander / ascent vehicle; centre: the modified SpaceX Starship; right: the National Team’s descent / ascent modules. Credit: NASA

Both Dynetics and Blue Origin believe the decision to go with SpaceX effectively locks-out opportunities for future engagement with NASA by others, and that if budgetary constraints were a contributing factor to the decision to limit the contract, the agency should have – under federal procurement requirements – sought alternative acquisition process resolutions rather than making a unilateral decision. Dynetics has also protested the manner in which “unstated evaluation criteria” was used by NASA to downgrade their lander proposal where previously it had been considered an effective approach.

By way of reply, NASA has stated it has released a RFI (request for information) asking companies for feedback on a future Lunar Exploration Transportation Services (LETS) contract to deliver crews and cargo to cislunar space / the lunar surface as a part of on-going Artemis operations.

Under GAO requirements, all work related to the SpaceX contract has been suspended pending review – which doesn’t preclude SpaceX continuing to work on the Starship HLS design off its own back.

Stratolaunch Resume Roc Flights

Stratolaunch, the nascent commercial launch platform company created by the late Paul Allen, co-founder of Microsoft, resumed flight tests of its massive dual-bodied aerial launch platform, nicknamed the Roc on April 29th, some two years after test flights were suspended.

The aircraft, which is the largest ever built (by wingspan) and has a double fuselage configuration baed on two former 747 aircraft, was originally conceived to handle airborne launches of a family of vehicles capable of delivering a variety of payloads to orbit. Officially the designated the Scaled Composites Model 351, Roc has had a chequered history, eventually being considered an unviable project by Vulcan, the investment company also founded by Allen, and which prior to his passing had funded Stratolaunch, and the company was sold-off to Cerberus Capital Management.

Roc – the Scaled Composites Model 351 – pictured during its April 29th 2021 test flight. Credit: Stratolaunch

Cerberus was initially uncertain as to what to do with Stratolaunch, but in April 2020, the company announced they were directing Stratolaunch away from the airborne launch platform market and into hypersonic aircraft development, specifically acting as an airborne launch platform.

In particular, Cerberus plan to us Roc in conjunction with two previously cancelled Stratolaunch projects – Hyper-A and Hyper-Z, rechristened Talon-A and Talon-Z. The first is a vehicle 8.5 metres in length and capable of testing hypersonic flight envelopes up to Mach 6. The larger Talon-Z will be used to test envelopes up to Mach 10. In particular, Cerberus has secured the interest of the US Defense Advanced Research Projects Agency.

An artist’s impression of the Talon-A. Credit: Stratolaunch

In preparation for this work, Roc will spend the next 12 months undetaking more and more advanced flight tests, increasing its operating altitude and flight range, in readiness for carrying Talon-A aloft starting in late 2022. Ass the first of these flights, Roc spent several hours in the air, completing high speed runs of up to 320 km/h, and climbing to an altitude of 4,300 metres.