ExoMars parachute tests delayed, mission faces review

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HELSINKI — The European and Russian space agencies have delayed crucial ExoMars 2020 parachute tests to late March, with the mission also set to face review.

“The high altitude drop tests of the two main parachutes are now planned for the end of March 2020,” an ESA spokesperson told SpaceNews via email. 

The tests of the 15-meter-diameter supersonic and 35-meter-wide subsonic parachutes—an essential part of the entry, descent and landing phase of the mission—had been scheduled for December and February. 

The delay comes despite six ground tests demonstrating successful parachute extraction – the point at which damage was caused in earlier, failed high altitude tests. 

Both tests need to be successful for the go-ahead for launch of 300-kilogram Rosalind Franklin rover during the July 25 to Aug. 13 Mars launch window. Any failure would mean a wait of 26 months for the next launch window, opening late 2022.

Agency heads to decide next steps

However the ExoMars mission could be condemned to delay before the tests are even carried out. The heads of ESA and Russian partner Roscosmos are set to meet next week to discuss next steps following a report on the progress of the mission.

A working-level review of the ExoMars 2020 project held late January, with a preliminary assessment communicated to the heads of the two space agencies on 3 February. 

In response, ESA’s Jan Woerner and Dmitry Rogozin of Roscosmos “instructed the respective inspectors general and program chiefs to submit an updated plan and schedule covering all the remaining activities necessary for an authorization to launch,” the ESA spokesperson stated.

“This plan will be examined by the two agency heads who will meet on 12 March to jointly agree the next steps.”

The decision will be announced at a press briefing held afterwards in Moscow shown live on ESA Web TV.

The ExoMars 2020 mission still faces a final review scheduled April 2020. Parachute issues and any other problems will need to have been solved by this point.

An issue with the rover Rosalind Franklin rover itself will need to be remedied, though this is not thought to be a major issue.

“There is a minor de-bonding of part of the solar array following the system environmental tests. This is a repeat of a problem seen during some earlier tests and a mechanical fix has been foreseen and will be implemented at TAS-I (Torino),” the ESA spokesperson said. “It is not seen as a serious problem.”

ExoMars Parachute tests unfold

A Russian Proton rocket is planned to launch ExoMars rover in July, reaching Mars in March 2021. It will employ a complex system of four parachutes, with two small pilot chutes used to sequentially deploy the supersonic ‘disc–gap band’ chute and subsonic main chute. 

High altitude drop tests of the 15-meter-diameter supersonic and 35-meter-wide subsonic parachutes failed in August and May 2019, threatening delay.

ESA turned to NASA’s Jet Propulsion Laboratory for assistance, with inspectors finding that damage to the chutes was caused at the point of extraction from their bags. “The focus is on adapting and simplifying the bag [rather] than touching the parachutes,” Francois Spoto, ExoMars program manager, told SpaceNews in September.

The new high altitude drop tests will be carried out in Oregon in the United States. The Esrange Space Center, northern Sweden, hosted the earlier tests.

The unprecedented size and complexity of the parachute system is related to the lander provided by Roscosmos. A more powerful retropropulsive system on the lander could have allowed the mission to require only one main chute, according to Spoto.

ESA and Russia failed to land on Mars with its joint ExoMars 2016 Schiaparelli demonstration lander. A computer issue led to the premature release of its parachute and brief firing of braking thrusters.

NASA, China and the United Arab Emirates are also planning to launch to the Red Planet in July and August.