From the Department of Not Really News

The rollout and first launch of NASA's Space Launch System (SLS) and its maiden (unmanned) flight have slipped again.  Pretty much as expected.   

Until this week, NASA had been publicly targeting a February 15 rollout date, when a mobile tower would ferry the SLS rocket from the Vehicle Assembly Building to its launch site at Kennedy Space Center in Florida. Tom Whitmeyer, deputy associate administrator for exploration systems development at NASA Headquarters, said the agency is now targeting "mid-March" for the rollout, but he did not want to set a specific date.

As recently as last October, NASA had expected to complete the wet dress rehearsal in December, now over a month ago.  That's when I wrote:

A launch date will be set after the completion of a wet dress rehearsal currently scheduled for December.  February '22 is likely to be the earliest the SLS could launch.

Now it's looking like the earliest rollout date is around March 15th.  A full, wet dress rehearsal (WDR) is nothing to take lightly, it's a tremendous accomplishment in the journey from early design sketches to operational rocket, as it tests all of the flight and ground systems short of actually lighting the engines.  As a general concept, it's not unheard of for the WDR on a new system to find unknown problems.  

Just by adding the few months late that they already are, if the WDR is late March instead of late December, add those three months to "the February of '22" earliest SLS launch date I speculated on and it's late May.  Eric Berger at Ars Technica continues to predict a summer launch date for SLS.  

In reality, NASA has held to virtually no published schedule since the SLS program began 11 years ago, with an initial launch target of 2016. So there is no reason to expect that situation to change. Assuming a relatively smooth wet dress procedure, therefore, NASA would feel pretty good about targeting a launch window from May 7 to May 21. But if there are issues that need to be addressed after the wet dress test on the launch pad, which seems likely, a summer launch of the Space Launch System is probably in the cards.

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SpaceX's Starlink launch yesterday put a couple of interesting touches on the performance we've been seeing.  Unless I missed the count somewhere along the way, I count 11 launches since December 1st, or more than one/week. Eric Berger at Ars Technica writes that the Falcon 9 may now be the safest rocket ever launched.  

As of yesterday, there have been 140 Falcon 9 launches.  Of those, one mission failed, the launch of an International Space Station cargo supply mission for NASA, in June 2015. Not included in this launch tally is the pre-flight failure of a Falcon 9 rocket and its Amos-6 satellite during a static fire test in September 2016; it's not included because it wasn't a launch.  The only in-flight incidents, where the flight didn't go as desired, were some failures to land the first stage, but those didn't affect the satellites delivered to orbit.  The recovery of the booster was always emphasized as something they wanted to do, but that wouldn't come at the customer's expense.  

Last month, the number of Falcon 9 launches exceeded the number of Space Shuttle launches; there were 135 of those, out of which 133 were successful.  In 2020, the Falcon 9 took the title of most experienced booster in the US inventory away from the Atlas V.  Since the Amos-6 satellite static firing failure, there has been a continuous run of 112 successful missions.  

[Russia's] Soyuz-U had a run of 100 successful launches from 1983 to 1986. This happens to be the exact same number of consecutive successes by the Delta II rocket, originally designed and built by McDonnell Douglas and later flown by Boeing and United Launch Alliance. Overall the Delta II rocket launched 155 times, with two failures. Its final flight, in 2018, was the rocket's 100th consecutive successful mission.

So the Falcon 9 has now exceeded both the Soyuz-U and Delta II rockets for consecutive mission successes, and apparently its low flight insurance costs reflect this.

As all SpaceX watchers have undoubtedly heard, Falcon 9 might well be superseded by Starship in the coming years, if all the design goals work out.  Starship and Super Heavy will revolutionize the space industry.  Even at a generous one flight/week, that's only 52 flights a year, so it will take long time to equal the total number of launches of some vehicles, notably Soyuz.  Across the dozen versions of the Soyuz, it has amassed over 1900 launches going back to 1957.  That milestone is probably not going to be reached.  

Falcon 9 will fly for the foreseeable future, though.  To borrow a closing line from Eric Berger at Ars:

That is because it now provides the only means for US astronauts to get into space. And while NASA's deep-space Orion vehicle and Boeing's Starliner spacecraft should come online within the next couple of years, the Falcon 9 rocket and Crew Dragon spacecraft will very likely remain the lowest risk, and lowest cost, means of putting humans into orbit for at least the next decade.

The launch of the Crew-3 mission on the morning of November 12th, last year.  That's a Crew Dragon Capsule on a Falcon 9.  NASA has come to see the numbers from booster re-use and accepted experienced boosters for even manned flight.  As a result, this was the ninth mission for this booster, and the mission went without a hitch.  The booster landed on recovery drone Just Read The Instructions NE of the Cape.