Posted on 12/22/2021 8:29:30 PM PST by BenLurkin
One of the dual digital computer units (DCU) in the engine controller for the number four RS-25, Engine 2060, stopped responding beginning on November 23. All four controllers were being powered up for Program Specific Engineering Testing (PSET) on the SLS Core Stage, which is stacked with the full Artemis 1 vehicle in High Bay 3 of the Vehicle Assembly Building (VAB) at the Kennedy Space Center (KSC) in Florida.
The dual channels on all four controller units powered up successfully on November 12 during other checkout testing prior to the failure on the 23rd. The engine controller units (ECU) are the major component that was upgraded between use of the formerly-named Space Shuttle Main Engines (SSME) on the final Space Shuttle launches and adaptation of the SSME Block II design for use on SLS as the RS-25.
The engine controller for the SSME and the new unit for the RS-25 is a primary component of the engine. The controller directly operates the engine, from diagnostics and checkout before firing, through thermal conditioning and purges for startup during vehicle propellant loading, through ignition and throttling during mainstage operation, all the way through shutdown and post-shutdown purges and safing.
The controllers accept commands and relay data to and from the SLS flight computers in the Core Stage for launch operations. In addition to the new controller for the RS-25, new control software that runs on the controllers was certified for use on SLS.
The new engine controllers still employ two redundant digital computer units (DCU) that operate on independent control channels, A and B. The DCUs can operate independently to provide full redundancy, but can also share or access some data from the other.
(Excerpt) Read more at nasaspaceflight.com ...
” two redundant digital computer units (DCU) that operate on independent control channels, A and B”
And if A and B have an argument, do they just shut the engine down and sulk??
No that’s when she calls Mother to get another vote ...
Does KISS apply?
When I had my shop, I delt with Ford engineers that did not fully understand how their air suspension system actually worked. They just knew that it worked ...KISS.
Artemis is dead: stop all payments and sue for refunds.
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