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I love that the video is extremely positive towards Starship and getting humans to Mars. It is also the first "popular" video I´m aware of which gets the negative lift approach and the belly flop right.

However one major part of the video is completely wrong.

Starship will not slow down via its engines prior to hitting the martian atmosphere for aerobraking. It will hit the atmosphere at interplanetary velocity.

The erroneous idea that spacecraft intended to land on Mars have to slow down before aerobraking has emerged on the internet in the recent months. And I don't know why.

All the rovers NASA has send to Mars in the last 20 years didn't slow down before aerobraking. They slammed into the atmosphere and used their heat shields to slow down until they were slow enough to deploy parachutes or execute their landing burns.

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This post is intended to clear up this misconception and maybe generate a bit of publicity for how EDL (entry decent landing) actually works for spacecraft.

After almost every accident in Starship development, people start claiming that SpaceX's "fail fast, learn faster" strategy is a mistake and they should go back to the classic Old Space strategies. Is that true? Is it really holding SpaceX back? To answer this question, I made a table of Apollo and Starship program milestones and added to them the projected date of the 1^st manned lunar landing if the Starship program took exactly the same amount of time from that milestone as the Apollo program.

It sounds crazy, but over the last 11 years Starship has been exactly on Apollo’s track with a deviation of ±1.6 year. Does that mean SpaceX will land on the Moon with astronauts in February 2026, as the average says? Probably not, but only because NASA is not so desperate now to approve the landing 1.5 years after the 1^st orbital flight of the Lunar Module and 4.5 months after its 1^st manned flight, as during the Apollo program. Currently, we’re nowhere near the 1968 level of risk tolerance, the US competitor in the space race is nowhere near to a super heavy-lift launch vehicle to the launch pad (like it 55 years ago), the president hasn't a firm deadline and Congress isn't to sign NASA a blank check to fulfill it.

Maybe another strategy would cost them less?

I think most of you have already guessed the answer, but just to be clear. In 2019, SpaceX was spending of their resources on the Starship project, which was in the region of $100-150M. By comparison, the Apollo program spent in current prices on launch vehicles in 1960, eclipsing everything SpaceX had spent on Starship and Raptor development to that point. SpaceX spending of this year is still less than the equivalent of the Apollo spending in 1961. The Apollo program's peak spending of $33.2B on launch vehicles and spacecraft in 1966 is simply unthinkable for SpaceX or even modern NASA.

It's all because of 60 years of technological advancement!

This may look like a legitimate argument at first glance, but is it true in reality? Excluding a experiments, the oxidizer-rich pre-burner was Russian technology, so SpaceX were to invent their own SX500 alloy for the Raptor. Methane-oxygen and full-flow rocket engines existed only as test articles before them. SpaceX also invented a stainless steel alloy for the Starship's hull and large identical hexagonal heat tiles instead of using the unique Space Shuttle tiles. Their idea of using has never been used to assemble a launch vehicles, let alone try to catch a boosters with them. And that's not counting dozens or rather hundreds more other details that we'll probably never know about because of trade secrets and ITAR.

Definitely technology has advanced in 60 years in a several places like computer-aided design and dynamic simulation. But in order to accurately simulate a methane rocket engine, you need to calculate physical parameters at points with chemical reactions running in parallel. So good luck with that! Something tells me that even with it and all the modern computing power you'll end up like Blue Origin your if you despise practical tests. Computer simulations are an addition to testing, not a replacement for it.

So although we have progress in technology, it's not as big as some of you might think. And it's all eaten up by the fact that SpaceX is trying to build a launch vehicle twice as heavy and 3 times more powerful than the Saturn V, which also should be fully and quickly reusable. SpaceX aims to make Starship as much of a technological marvel as Saturn V was in its day. And they're trying to do it with a third of the Apollo era NASA and probably an order of magnitude fewer contractors.

A few other examples:

Space Shuttle design studies

26 July 1972 Shuttle final design

Manned Space Shuttle flight

Orion design studies

21 June 2012 Orion service module studies

21 November 2012 Orion service module final design

5 December 2014 Orion test flight

16 November 2022 Orion and service module test flight

Crew Dragon design studies

Crew Dragon final design

Manned Crew Dragon flight

Apollo chronology:

Start of the F-1 engine program

Start of the Saturn launch vehicle program

11 September 1958 NASA awarded the F-1 contract to Rocketdyne

31 December 1958 Subscale F-1 test

March 1959 F-1 full-scale injector and thrust chamber tests

March 1960 F-1 full-scale gas generator tests

November 1960 F-1 full-scale turbopump test

Saturn V final design

Proposals for the Apollo Lunar Module

28 June 1962 Combustion instability caused the F-1 loss

7 November 1962 NASA awarded Apollo Lunar Module contract

April 1963 Apollo Lunar Module final design

Saturn 1 flight (with 2^nd stage prototype)

F-1 full-thrust, long-duration test

F-1 completed flight rating tests

9 November 1967 Saturn V flight

Apollo Lunar Module unmanned flight

Apollo Lunar Module manned flight

20 July 1969 Manned lunar landing

Starship chronology:

Start of the methane Raptor program

Start of the fully reusable Starship program

Raptor injector elements test

April 2015 Raptor oxygen preburner test

USAF awarded the Raptor contract

Early 2016 Raptor test stand built

Subscale Raptor test

September 2017 Raptor achieved 200 bars with SX500 alloy

Starship final design

Raptor achieved power level need for SH and Starship

Starhopper flight

Proposals for the Artemis lander

June 2020 Raptor achieved 300 bars chamber pressure

NASA awarded Starship contract

100^th Raptor build

Raptor 2 passed static fire tests

200^th Raptor build

Raptor 3 achieve 350 bar

Starship’s IFT-1 flight