Slashdot Mirror
SpaceX Successfully Tests Crew Dragon Landing Parachutes
SpaceX successfully tested out the parachute system it plans to use to land its Crew Dragon spaceship safely back on Earth today. By using a "mass simulator," SpaceX was able to replicate the weight and shape of the spacecraft. According to NASA, "Later tests will grow progressively more realistic to simulate as much of the actual conditions and processes the system will see during an operational mission."
The goal of the test was to evaluate the four main parachutes, but this test did not include the "drogue chutes" the full landing system will utilize. The aim is for the spacecraft to splash safely into the ocean carried down by parachutes to reduce its speed. Eventually, SpaceX intends for the spacecraft to land upright on solid ground by utilizing eight SuperDraco propulsion engines. SpaceX successfully landed its Falcon 9 rocket at Cape Canaveral in December. Earlier this month, a SpaceX Falcon 9 exploded upon landing on a drone ship.
The goal of the test was to evaluate the four main parachutes, but this test did not include the "drogue chutes" the full landing system will utilize. The aim is for the spacecraft to splash safely into the ocean carried down by parachutes to reduce its speed. Eventually, SpaceX intends for the spacecraft to land upright on solid ground by utilizing eight SuperDraco propulsion engines. SpaceX successfully landed its Falcon 9 rocket at Cape Canaveral in December. Earlier this month, a SpaceX Falcon 9 exploded upon landing on a drone ship.
SpaceX love fourfold symmetry: octagonal layout of stage 1 rockets (plus one central, for 9 total). Four landing legs. Four steering fins at the top of stage I. Four pairs of "super Draco" landing/abort rockets on the Dragon. And now, four chutes.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
There is a thing that these chutes do, where on initial deployment the open aperture of the chute is quite small, and the chute looks rather like a sausage. Then later on, the chute abruptly opens fully, and looks like a hemisphere. (The transition wasn't shown in the video in TFA, but I've seen it elsewhere and it is also simulated in Kerbal Space Program.)
How is this achieved? Is it some clever aerodynamics where the chute has two stable configurations and a 'catastrophic' transition? Is there some rope which constrains the aperture early on and then is somehow severed to allow fully deployment?
(I understand why - the first configuration slows the payload sufficiently so that the chute is not torn apart when it fully deploys. "How" is what I don't know.)
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.