Nighttime rehearsal for Ariane 6 toward first flight

Yesterday, a workforce of CNES, ESA, Arianespace and ArianeGroup personnel at Europe’s Spaceport in Kourou, French Guiana, accomplished a full-scale moist rehearsal of the brand new Ariane 6 rocket that was fueled after which drained of its gasoline. The take a look at lasted over 30 hours with three groups working in shifts of 10 hours every.

The objective was to extend the robustness of the launch system and to check emergency security procedures with an interruption of the countdown from simulated anomalies.

The moist rehearsal—referred to as mixed take a look at loading, abbreviated to CTLO2.1—is the third time the Ariane 6 floor groups have practiced a full launch countdown, after a primary rehearsal on 18 July and a primary ignition of the principle engine on 5 September. Yesterday’s take a look at focused on system robustness and the way nicely Ariane 6 and the groups deal with conditions on the fringe of the operational parameters.

This time, the operations have been carried out at evening to check operations in cooler ambient temperatures, whereas the July and September checks have been run in daylight.

“The entire workforce carried out this CTLO2.1 countdown to close perfection,” exclaims Jean-Michel Rizzi, ESA Ariane 6 launch base supervisor, “it was a really lengthy operation however the devoted groups and efforts put in achieved a whole success, bravo to everyone concerned.”

Chilly liquid gasoline—and many it

Ariane 6 makes use of liquid oxygen and hydrogen as its gasoline to energy into space. These power-dense liquids are nice fuels however have to be chilled to extreme temperatures beneath -250°C, making them hazardous to work with. At these temperatures the liquids will immediately broaden if it heats up and might trigger condensation and even ice on the rocket because it cools down within the surrounding tropically humid air.

Ariane 6 tanks maintain 180 tons of propellant, which is why fueling after which draining operations take so lengthy—it took over seven hours to empty the liquid hydrogen from its tanks alone. Engineers are always adapting flow rate and monitoring temperatures, strain within the tanks and pipes, and the bottom programs underground pipelines that stretch via a whole bunch of meters to move the gasoline to the rocket.

The core stage of the Ariane 6 now standing on its launchpad is similar to the true factor, however it isn’t meant to go away Earth. The rocket boosters are inert as they use stable propellant and do not require fueling, however the remainder is the true deal—together with the Vinci upper stage that might solely hearth its engines as soon as separated from the core stage in space. The fueling of the higher stage can also be included in all rehearsals.

“We put together for a launch, or on this case a rehearsal, many days prematurely,” says Tony dos Santos, ESA’s Ariane 6 floor programs operations supervisor at Kourou, “the bottom tanks the place we retailer the liquid hydrogen and oxygen have to be replenished, the launchpad must be primed and ready: it is an all-hands operation working in shifts that could be a main collective effort involving groups from ESA, CNES, Arianegroup and Arianespace based mostly on either side of the Atlantic, each in Les Mureaux, France, and Kourou.”

“Tonight-time rehearsal allowed the groups to follow loading the rocket with gasoline when the temperature outdoors is decrease—with out the tropical daylight shining on the Ariane 6 tanks the gasoline inside behaves noticeably completely different and we have to think about and accommodate for condensation and ice formation.”

Rehearse for launch

“As these operations are so delicate, and Ariane 6 is an all-new launch system, the extra rehearsals we are able to do, the higher, as a result of we have to discover the robustness of the programs.” explains Pier Domenico Resta, ESA’s Ariane 6 launch system and engineering supervisor, “Via simulations of off-nominal conditions the CTLO 2.1 has given the operational groups extra confidence in launch countdowns and extra take a look at knowledge for evaluation and clean operations to liftoff.”

After this profitable rehearsal, the following main take a look at will flip up the warmth: a full eight-minute firing of the Ariane 6 rocket’s principal engine that might usually propel the rocket and its passengers into space. For this take a look at, scheduled earlier than the top of November, the Ariane 6 take a look at mannequin will proceed to remain firmly mounted to the bottom.

“We’re working all out to get Ariane 6 off the bottom and looking out ahead to see it rise from the launchpad quickly,” concludes Pier Domenico.