[troutman]

Why did NASA retire the Space Shuttle?
The Space Shuttle was NASA’s workhorse for 30 years. But despite all its features, it had some fatal flaws.

https://astronomy.com/news/2020/11/w...flying%20again.

First — and perhaps most importantly — the program was wildly expensive. The average cost of a shuttle launch was a mind-boggling $450 million, far more than NASA had predicted. While the shuttle was proposed to make disposable rockets a thing of the past, it did exactly the opposite. Most customers who wanted to put satellites into orbit found conventional rockets to be a cheaper alternative.

Second, the proposed launch schedules and turnaround times for the shuttle fleet were essentially fantasy. The fastest turnaround for any shuttle in the history of the program was 54 days. And after the Challenger disaster, the fastest turnaround was 88 days — a far cry from what NASA officials thought they could accomplish. Slower turnarounds meant fewer flights, which meant less access to space for paying customers, further driving business away from NASA.

The shuttle was revealed to be a high-risk, experimental vehicle — something most astronauts had known all along. The subsequent investigation also revealed serious problems with NASA’s safety culture. Still, the space agency took its lashings and made the changes required to get the shuttle flying again.

But 17 years after Challenger, Space Shuttle Columbia broke apart while reentering Earth’s atmosphere. Yet again, the entire crew — this time featuring the highly publicized first Israeli astronaut, Ilan Ramon — was killed. Although the technical cause of the Columbia disaster was very different than what led to the loss of Challenger, the investigation again found deep cultural problems at NASA.

The tragedy drove home that the Space Shuttle could never be truly safe.