Some people think that Obama cancelled Constellation and the Moon mission because it was “not invented here.” He did not want to be the president who fulfilled a major mission for Bush.

https://www.newser.com/story/86164/obama-says-of-the-moon-been-there-done-that.html

But the moon is old news, and it’s time to think bigger. “We’ve been there before,” [Obama] said at Kennedy Space Center, unswayed by critics who say his vision will bring an end to manned spaceflights.

However, there were some technical issues that needed to be dealt with. These came because they added an additional segment to the SRB stack from the Space Shuttle.

https://blogs.nasa.gov/Ares_I-X/tag/vibration/

Before 70 seconds and after 90 seconds the vibration levels are fine, but for those 20 seconds we haven’t fully verified that we can still steer the rocket with the TVC or send the signal to self-destruct the rocket and end the flight with the FTS if it veers away from its projected path.

To help explain:

The vibration that is produced by the burning of the solid rocket propellant in the first stage booster is called thrust oscillation. These vibrations — or oscillations — come in the form of waves, which travel up and down the length of the rocket like a musical note through an organ pipe. One of the biggest challenges in any rocket design is developing avionics (aviation electronics) that can function in this vibrating environment.

As an additional note: another challenge is to prevent too much vibration from being in the range of the natural frequency of a human being, roughly 8Hz to 80Hz. Internal organs tend to have a frequency of around 20 to 25Hz, so they might pound against each other until they become jelly, if the vibrations are too much at this frequency. The head has another frequency, the spine another, etc. It is all part of rocket science.

“But, it’s gonna take money.
A whole lot of spending money.
It’s gonna take plenty of money,
To do it right, child.”

Additional question. Are they planning to make new RS-25 engines? As in understand, there are 4 per SLS. They will run out of them. I count 9 in existence . This is a limiting factor.

A report like this will result in volumes more of procurement regulations to be administered by bus loads of new bureaucrats (non of which engineers ) which will move decisions farther away from the knowledgeable technical people. It will result in only using current vendors because it becomes more difficult to qualify new suppliers. And it will take much more time for a project which will escalate the costs and sap the will of those trying to achieve. Atlas Shrugged has never seemed more accurate.

A stack of 18 billion one-dollar bills is about 1200 miles high. From that perspective, SLS has finally reached orbit.

I dunno. “How many votes will this buy me?” has non-mathematical components, to be sure, but there is still some arithmetic involved.

Call Me Ishmael: What Congress critters do is not math, no matter what their calculations.

Actually they can do math just fine; they’re just not calculating the same things as we are.