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Wednesday 14 June 2023

Comment on Starship Orbital Test Flight Raises Serious Questions by Jim Hillhouse

In reply to spacerfirstclass.

NASA Folks

Let’s start with the NASA folks you disparage. They, not SpaceX, very nearly flawlessly launched a rocket (ok, an elevator door in the MLP was wrecked) that sent a crew-designed spacecraft to the Moon and farther in space that any crew-designed spacecraft has ever gone, then safely returned to Earth.

So maybe when the folks who manage to do this when none other have know that of which they opine.

Replacing SpaceX Lunar Lander

The point I unsuccessfully made to you was that NASA, by hitching its Artemis III lunar landing to SpaceX’s Starship program, has boxed itself in. ESDMD head Free’s recent comments underscore that point.

And NASA has no recourse but to either hope SpaceX gets back on track, which doesn’t look likely at this point, accelerate Blue Origin’s development of its lunar lander by moving its schedule 3-4 years to the left, which also is unlikely, or retask Artemis III and IV.

Know How

The other point I tried (unsuccessfully) to make about “know-how” was that SpaceX owns its lander IP, all of it. Were SpaceX a NASA contractor building a gov’t owned system such as Orion or SLS, that wouldn’t be the case. Case in point, SLS’s blue-prints, digital, paper, or otherwise, as well as the factory, machinery, etc. are the property of NASA. If NASA turned over the construction of SLS to another contractor, the people building SLS would just transfer to that new contractor.

Yes, those employees’ know-how is critical. And NASA largely succeeded in preserving the Shuttle workforce at Michoud in hopes of retaining its know-how to help with the construction of SLS. But it turns-out that SLS was much more difficult to build than Shuttle’s simple External Tank. The last time a first stage booster with engines was built at Michoud was in 1971, the Saturn S-IC. That was the know-how, which retired decades ago, that would have been more relevant to building SLS’s Core Stage.

Starship Lunar Lander Descent Abort Capability

You previously stated that the Starship lunar lander concept has a descent abort capability. You stated,

“Attachment A01 “Human Landing System Concept of Operations” of the HLS BAA, page 10 “Descent Abort””

First, when you mention a gov’t document to support your claim like that, link it.

And you’re right; Starship should not have been awarded its lunar lander contract. The award was very controversial because a disqualifying point was no descent abort capability.

Here’s something you can do, contact SpaceX and ask for information specifically on the lander’s descent abort capability.

Starship Abort Capability

“Because if they separate the ship from the booster too early, the ship doesn’t have enough delta-v to reach the planned splash down point near Hawaii, I don’t know why this is hard to understand.”

You are saying that having the abort system would have meant that the aborting Starship wouldn’t have had enough delta-V to make it to Hawaii?

It’s also true that if the launch of Artemis I had gone badly, the Orion spacecraft’s abort would have interfered with its eventual successful lunar mission. That’s not the point of a launch abort system.

When a launch abort system engages, the mission is done and it’s just about getting the payload, crew, to a place hopefully far enough away from where the rest of the launcher’s debris is landing. SpaceX lost a valuable piece of hardware because Starship didn’t abort.

You mention that SpaceX’s (NEPA?) statement only covered a splash-down in Hawaii. Ok, so Starship had enough fuel to provide sufficient delta-V eject from SHB and land in Hawaii but not enough to abort from launch and land elsewhere, say at Starbase?

I think Elon’s BS get you all twisted in a knot that prevents you from seeing the forest for the debris he throws up.

Abort System Is A Crucial Path

Pad and launch abort systems are a critical path and are usually tested long before an all-up test flight. Apollo’s first pad abort test was on Nov. 7, 1963. It was used on the Apollo 4 test flight in Nov. 1967. Orion’s first pad abort test was on May 6, 2010. Orion’s abort system was available on last year’s Artemis I test flight. The fact that Starship could, after a successful launch, separate and then land in Hawaii means that the abort system either the capability doesn’t exist, wasn’t activated or failed. I will wait for the FAA mishap report to learn which it was.

SHB FTS

Elon Musk has said that SHB did activate its FTS. If true, that’s good news. And if the FAA mishap report confirms that claim, then I stand corrected. The bad news is that it didn’t work very well. And if SpaceX already redesigned and tested the new FTS, then more good news. Hopefully this new FTS on SHB will destroy the launcher in less than the nearly 2 minutes it took for the first version to do so.

Red Dragon

I knew enough about Red Dragon to read that AIAA paper, among others, in confirming a source’s claim that the mission was BS. So, why don’t you take the trouble to read the paper I referenced (AIAA 2011-7216 is available at https://arc.aiaa.org/doi/pdf/10.2514/6.2011-7216 where you can purchase a copy), focus on page 16, do some of the patched-conic math (see Vallejo’s “Fundamentals of Astrodynamics and Applications, 5th Ed.”, available at https://www.amazon.com/Fundamentals-Astrodynamics-Applications-Fifth-Vallado/dp/1881883221) to get you from LEO, heliocentric, Mars capture, and powered-descent phases, and learn for yourself that Red Dragon, even stripped-down, would never have even made it to Mars with sufficient fuel mass to for a landing in the time frame SpaceX was considering. That’s why Elon eventually canceled it in 2017.

NASA Space Act Agreements

A Space Act Agreement with NASA only means that it will help a company with the resources to the extent the agency can and for the agreed upon sum sufficient to pay for that assistance. That’s all.

Don’t agree with that? Well, then contact NASA HQ’s PAO and ask.

CyberTruck

Hey, I was also on Twitter and saw that CyberTruck won’t be in production later this year. Here’s a link (https://www.motortrend.com/news/tesla-cybertruck-issues-delayed-development-leaked-report-2023/).

FSD?

LOL!



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via World Space Info

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