China's Space Program Thread II

[Quickie]

That is an FTS as I was saying. A Flight Termination System. Assuming the LV was designed with a non automatic FTS, it would use something like a high powered coded UHF link between the site and the rocket. An RSO then could order the rocket to "unzip" if it violated an instantaneous impact point.

As was evident by the video of the test, the first stage did not have an FTS installed and/or active.

If I could wager a guess...probably because it was assumed it would not take flight in the first place..this was supposed to be a WDR/static fire test of a single stage of the LV.

I never said there was an FTS in the testing of the Tianlong rocket's first stage in the first place.

The point I was trying to make was this:

" A static test stand control center does have the ability to cut off the engines any time any anomalies are detected through the sensors. We have seen this happen many times during the testing of new Starship Boosters. "

We have witnessed the shutdown of the new Starship boosters' engines within seconds of the ignition of engines due to the detection of anomalies. The testing of the Tianlong rocket's first stage should have similar contingency procedures, such as the immediate shutdown of the engines, put in place to prevent the possible catastrophic explosion of the engines possibly causing more extensive damage involving the test stand and the surrounding facilities. Commands can be preprogrammed if the response time is too fast for human action.

 

[Dante80]

I never said there was an FTS in the testing of the Tianlong rocket's first stage in the first place.

The point I was trying to make was this:

" A static test stand control center does have the ability to cut off the engines any time any anomalies are detected through the sensors. We have seen this happen many times during the testing of new Starship Boosters. "

We have witnessed the shutdown of the new Starship boosters' engines within seconds of the ignition of engines due to the detection of anomalies. The testing of the Tianlong rocket's first stage should have similar contingency procedures, such as the immediate shutdown of the engines, put in place to prevent the possible catastrophic explosion of the engines possibly causing more extensive damage involving the test stand and the surrounding facilities. Commands can be preprogrammed if the response time is too fast for human action.

For the third time, I am trying to explain to you. What you are describing does not exist. Not in Starship and not here. This is not how things work in real life. There is no emergency connection between the control center and the stage computer, nor is there a command to send or give in a test like this, other than to a FTS , if it exists or is active. In this case, an FTS either didn't exist, or was not armed.

The on-board computer had exclusive automatic control of the stage, and the test. It was handed off said control after the WDR. After this point, ONLY the computer can abort the test or stop it after it starts. The control center is out of the picture, period. It's job is to observe, not to control.

Most importantly, we know for a fact that the on-board computer had control of the stage because Space Pioneer told us so in their press release.

The stage computer could not shut down the engines if there was no combustion instability or loss of tank pressure. It could not detect that the stage literally lifted off, it was not its job. And the engines were working perfectly.

In the end, it shut off the stage either because it detected an engine/tank anomaly (due to the structural damage incurred by the stage lifting off) or because it reached the run time set for the static fire test.

That is all there is to it so far, at least from the info we can access publicly and reasonably analyze.

 

[Quickie]

For the third time, I am trying to explain to you. What you are describing does not exist. Not in Starship and not here. This is not how things work in real life. There is no emergency connection between the control center and the stage computer, nor is there a command to send or give in a test like this, other than to a FTS , if it exists or is active. In this case, an FTS either didn't exist, or was not armed.

The on-board computer had exclusive automatic control of the stage, and the test. It was handed off said control after the WDR. After this point, ONLY the computer can abort the test or stop it after it starts. The control center is out of the picture, period. It's job is to observe, not to control.

Most importantly, we know for a fact that the on-board computer had control of the stage because Space Pioneer told us so in their press release.

The stage computer could not shut down the engines if there was no combustion instability or loss of tank pressure. It could not detect that the stage literally lifted off, it was not its job. And the engines were working perfectly.

In the end, it shut off the stage either because it detected an engine/tank anomaly (due to the structural damage incurred by the stage lifting off) or because it reached the run time set for the static fire test.

That is all there is to it so far, at least from the info we can access publicly and reasonably analyze.

" What you are describing does not exist. Not in Starship and not here. "

Huh? Did you see how Space X does the static testing of Raptor engines of their new Starship booster?



Bear in mind the Tianlong rocket is meant to be a reusable rocket and for that to happen the rocket engine must have the ability to do a total engine shutdown at the completion of the landing back on the pad. In that case, the static rocket engine test is also an opportunity to test engine shutdown as part of the overall test.

What you are suggesting is Space Pioneer is omitting the testing of this critical reusable rocket function i.e. engine shutdown function when they have spent so much time and money on building a rocket engine designed to be reusable.

It will be a boomer if that is the case and it makes the static testing so much more dangerous as they are bunching so many powerful engines and firing them all at once without the ability to shut them down. Also, redundancy of the 9 engines requires any of the faulty engines to have the ability to do a complete shutdown (in order to not cause an explosion for example).

Let us see what sort of information they will come up with in the coming days and how much, or less, of the static engine test is gearing towards their aim of building a reusable rocket.

 

[Dante80]

Huh? Did you see how Space X does the static testing of Raptor engines of their new Starship booster?

Yes.

Bear in mind the Tianlong rocket is meant to be a reusable rocket and for that to happen the rocket engine must have the ability to do a total engine shutdown at the completion of the landing back on the pad. In that case, the static rocket engine test is also an opportunity to test engine shutdown as part of the overall test.

What you are suggesting is Space Pioneer is omitting the testing of this critical reusable rocket function i.e. engine shutdown function when they have spent so much time and money on building a rocket engine designed to be reusable.

No. What I am saying (not suggesting, I am explaining to you something that is objectively true in all modern LVs) is that shutdown function is handled exclusively by the on-board computer, not the test stand or the control center. And the on-board computer ordered a shut down of the engines indeed, as we plainly saw in the mishap video, and as Space Pioneer themselves communicated to us.

During the test run, the first-stage rocket ignited normally, and the engine thrust reached 820 tons. Due to structural failure at the connection between the rocket body and the test bench, the first-stage rocket separated from the launch pad. After liftoff, the onboard computer automatically shut down, and the rocket fell into a deep mountain 1.5 kilometers southwest of the test bench. The rocket body disintegrated after falling into the mountain. The test site is far away from the urban area of Gongyi. Before the test, we worked with the local government to improve safety measures and organize the evacuation of surrounding personnel in advance. After investigation, no casualties were found.

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I don't know how else to get my point across. English is not my first language so maybe I am doing something wrong. Sorry, I have to give up.

 

[Quickie]

Yes.


No. What I am saying (not suggesting, I am explaining to you something that is objectively true in all modern LVs) is that shutdown function is handled exclusively by the on-board computer, not the test stand or the control center. And the on-board computer ordered a shut down of the engines indeed, as we plainly saw in the mishap video, and as Space Pioneer themselves communicated to us.

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I don't know how else to get my point across. English is not my first language so maybe I am doing something wrong. Sorry, I have to give up.

But here we are dealing with the static test stand of the first-stage rocket engines and not an operational LV.

In this way, the hierarchy of commands between the control center computers and test stand/rocket stage computers can be quite different. It may be that the breakdown of communication to the mission control computer was causing "the onboard computer to automatically shut down after liftoff".

For all we know, the control center computers are hard-wired to some of the test stand/rocket engine sensors and actuators.

 

[Wrought]

Sorry guys, MSS says you're talking too much about state secrets.

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[gelgoog]

The on-board computer had exclusive automatic control of the stage, and the test. It was handed off said control after the WDR. After this point, ONLY the computer can abort the test or stop it after it starts. The control center is out of the picture, period. It's job is to observe, not to control.

Most importantly, we know for a fact that the on-board computer had control of the stage because Space Pioneer told us so in their press release.

The stage computer could not shut down the engines if there was no combustion instability or loss of tank pressure.

Sure it can. You just shut down the valves from the propellant tanks to the turbopumps. And the combustion will cease quicksnap.
If there is no propellant to burn, the rocket engine will cease to provide thrust.

It could not detect that the stage literally lifted off, it was not its job. And the engines were working perfectly.

It wouldn't be that hard to add accelerometers to the rocket that could detect if it was lifting off or not. Or you could add a pitot tube similar to one in an aircraft. Or whatever.

In the end, it shut off the stage either because it detected an engine/tank anomaly (due to the structural damage incurred by the stage lifting off) or because it reached the run time set for the static fire test.

The flight computer might operate that way. But saying it is the only way such a thing could operate is a real stretch.
Conventional rockets do have explosives which can be remotely activated from the control room to destroy the rocket.

Have you never heard of flight termination systems?

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[tiancai8888]

What if they want to test longer burn and weight gets much lighter? This is way too little margin no matter how you slice it

As far as I know, 30s test duration was programmed.
According to SP , 820t of thrust was generated during the "launch", The ISP of TH12 engine at sea level is 285s.
We can roughly calculate the stage would consume 2.9t of proprollent per sec and around 87t after the test.

if they keep the throttle straight the margin would be 30% before the test & 15% after

I won't deny the margin is low. but it's still inside the perimeter

We can call them reckless, but I don't think they are that fooilsh to make such mistake with such plain data avaliable.

 

[PopularScience]

For the third time, I am trying to explain to you. What you are describing does not exist. Not in Starship and not here. This is not how things work in real life. There is no emergency connection between the control center and the stage computer, nor is there a command to send or give in a test like this, other than to a FTS , if it exists or is active. In this case, an FTS either didn't exist, or was not armed.

The on-board computer had exclusive automatic control of the stage, and the test. It was handed off said control after the WDR. After this point, ONLY the computer can abort the test or stop it after it starts. The control center is out of the picture, period. It's job is to observe, not to control.

Most importantly, we know for a fact that the on-board computer had control of the stage because Space Pioneer told us so in their press release.

The stage computer could not shut down the engines if there was no combustion instability or loss of tank pressure. It could not detect that the stage literally lifted off, it was not its job. And the engines were working perfectly.

In the end, it shut off the stage either because it detected an engine/tank anomaly (due to the structural damage incurred by the stage lifting off) or because it reached the run time set for the static fire test.

That is all there is to it so far, at least from the info we can access publicly and reasonably analyze.

"Our engine is too good and the performance is too strong." The above staff member said. He also said that after the rocket (accidentally) took off, the company took the initiative to shut down the rocket and let it fall. "This is what we set up first. It must be shut down. There is a plan."

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[totenchan]

"Our engine is too good and the performance is too strong." The above staff member said. He also said that after the rocket (accidentally) took off, the company took the initiative to shut down the rocket and let it fall. "This is what we set up first. It must be shut down. There is a plan."

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Whether this is true or not aside (though there are posts on weibo and elsewhere contradicting this story), this seems like a very flippant way to dismiss an event that very obviously was not adequately prepared for and very easily could have led to loss of life. If this is the attitude with which this company intends to approach these problems, they deserve to fail. LandSpace has always been the more innovative company anyways.