NASA thinks engine issue on SLS launch caused by misreading sensor
NASA engineers have now concluded that the improper temperatures in one engine in SLS’s core stage that forced the August 29, 2022 launch to be scrubbed were caused by a faulty sensor, and that the actual temperatures in the engine were correct.
During a news conference on Tuesday evening, NASA’s program manager for the SLS rocket, John Honeycutt, said his engineering team believed the engine had actually cooled down from ambient temperature to near the required level but that it was not properly measured by a faulty temperature sensor. “The way the sensor is behaving does not line up with the physics of the situation,” Honeycutt said.
The problem for NASA is that the sensor cannot be easily replaced and would likely necessitate a rollback to the Vehicle Assembly Building at Kennedy Space Center in Florida, a few kilometers from the launch pad. This would delay the launch of the rocket at least into October, and the space agency is starting to get concerned about wear and tear on a rocket that has now been stacked for nearly a full year.
With this SLS rocket, NASA management is now trapped between a rock and a hard place. The rocket’s solid rocket boosters has been stacked for just short of two years, almost a full year beyond their use-by date. Moreover, there are batteries on the rocket that only function for about a month before they must be replaced. Their replacement date is September 6th, which means if NASA cannot get the rocket launched by that date it will have to return it to the assembly building, delaying the launch to at least October. If it has to replace the solid rocket boosters the launch will likely then be delayed until next year, which will seriously impact the second SLS launch, set to send astronauts around the Moon and back.
At the moment the launch is scheduled for a two hour launch window beginning at 2:17 pm (Eastern) on Saturday, September 3, 2022. The countdown will be live streamed here. At the moment the weather for Saturday has improved, with s 60% chance the launch can proceed.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
NASA engineers have now concluded that the improper temperatures in one engine in SLS’s core stage that forced the August 29, 2022 launch to be scrubbed were caused by a faulty sensor, and that the actual temperatures in the engine were correct.
During a news conference on Tuesday evening, NASA’s program manager for the SLS rocket, John Honeycutt, said his engineering team believed the engine had actually cooled down from ambient temperature to near the required level but that it was not properly measured by a faulty temperature sensor. “The way the sensor is behaving does not line up with the physics of the situation,” Honeycutt said.
The problem for NASA is that the sensor cannot be easily replaced and would likely necessitate a rollback to the Vehicle Assembly Building at Kennedy Space Center in Florida, a few kilometers from the launch pad. This would delay the launch of the rocket at least into October, and the space agency is starting to get concerned about wear and tear on a rocket that has now been stacked for nearly a full year.
With this SLS rocket, NASA management is now trapped between a rock and a hard place. The rocket’s solid rocket boosters has been stacked for just short of two years, almost a full year beyond their use-by date. Moreover, there are batteries on the rocket that only function for about a month before they must be replaced. Their replacement date is September 6th, which means if NASA cannot get the rocket launched by that date it will have to return it to the assembly building, delaying the launch to at least October. If it has to replace the solid rocket boosters the launch will likely then be delayed until next year, which will seriously impact the second SLS launch, set to send astronauts around the Moon and back.
At the moment the launch is scheduled for a two hour launch window beginning at 2:17 pm (Eastern) on Saturday, September 3, 2022. The countdown will be live streamed here. At the moment the weather for Saturday has improved, with s 60% chance the launch can proceed.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Has anyone from NASA asked VP Harris what she thinks they should do?
TONY
All I want to do to that woman is to trick her into getting inside the capsule, shutting the door and sending her around the moon.
Just to test the life support system.
Since the current plan is to tweak the flight computer to ignore the higher temperature reading during engine chill down, do they also have to ignore higher Engine #3 temperature readings on the way up? I recall that we had a STS abort to orbit due to faulty sensor high temperature readings. Perhaps they use another sensor on the way up to orbit.
So many really ‘smart’ people (NASA, Congress, contractors); what a mess.
The meaning of “smart” has changed.
Kick the tires and light the fires, NASA. The sensor’s faulty, but the rest is fine!
OK so the rocket doesn’t have tires.
The leeway on standards they allow themselves compared to the high standards they hold their competition will not bode well unless NASA gets very, very lucky on Saturday. I wonder what the betting odds are in Ireland.
My book says:
50 – 50 back to the VAB
30 – 70 launch Saturday
Bloody sensors were the cause of my recent car problems. Ugh!
Braille fails when the door slams your fingers.
Hydrogen leak while fueling……
NASA needs to shelve this turkey.