So they need to fuel the second stage to test the first stage engines.
I get it, they need the extra weight so the clamps hold the rocket in place. Or could they do the test if they ran each of the engines in sequence rather than all at once and get qualified? Or it is a pump test to run full throttle on all at once?
Could be static from flow, could be some employee not cleaning all the seals correctly or the connection not mating perfectly. In any case this is a tough one to lose like that. At least the second stage isn't reuse so it was all new and they can't blame it on reuse.
I sure wouldn't want to be the employee who connected the hoses ...
Good eye Mike. Here are two frames cut from archae86's video link. They are 1 second apart. They seem to support some sort of external malfunction. Not sure that they add more than the pics you posted Mike. I was hoping to capture more frames within the 1 second period that would show the outward expansion of the detonation pt.
When I saw the original video on the local TV it appeared as though someone had put about 30 windings of det-cord around the circumference and hit the plunger.
Interestingly I think detonation might indeed be a more accurate word ( as opposed to 'ignition' ). I couldn't say without more exact timing & distances but if the edge of that blast front is moving faster than the speed of sound ( 330 m/s ) then ideas about causation change c/w subsonic ....
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
So they need to fuel the second stage to test the first stage engines.
Not really, but "Test as you fly" is a doctrine. They don't reason through the necessity of each particular bit.
As it happens, most folks don't do hot-fire tests with the payload in place. And apparently for SpaceX doing it that way was not firmly a consequence of doctrine, but considerably for wanting to shave a day off the total sequence.
Considering that at SpaceX launch prices it is probably quite common for the payload to cost more than the launch vehicle, someone may push back on this particular bit of improvement.
I've been looping the video at highest resolution on my big LED TV. Thoughts :
- that's a minimum 1/2 billion dollar loss to SpaceX, direct/indirect/etc.
- the craft wasn't fully fueled. Sounds odd to say but the explosion was too small & the damage too limited. A complete load ought have flattened the entire complex plus margin.
- the ongoing explosions at ground level tried to track to the right along feed lines but fortunately didn't make it ( no doubt suitable valves cut in ) to the big LOX sphere. Whew !
- there was an apparent change in the upper stage venting about 25 seconds prior to explosion.
Cheers, Mike.
( edit )
Quote:
September 1, 1:28pm EDT
At approximately 9:07 am ET, during a standard pre-launch static fire test for the AMOS-6 mission, there was an anomaly at SpaceX’s Cape Canaveral Space Launch Complex 40 resulting in loss of the vehicle.
The anomaly originated around the upper stage oxygen tank and occurred during propellant loading of the vehicle. Per standard operating procedure, all personnel were clear of the pad and there were no injuries.
We are continuing to review the data to identify the root cause. Additional updates will be provided as they become available.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
SpaceX has begun the careful and deliberate process of understanding the causes and fixes for yesterday's incident. We will continue to provide regular updates on our progress and findings, to the fullest extent we can share publicly.
We deeply regret the loss of AMOS-6, and safely and reliably returning to flight to meet the demands of our customers is our chief priority. SpaceX's business is robust, with approximately 70 missions on our manifest worth over $10 billion. In the aftermath of yesterday's events, we are grateful for the continued support and unwavering confidence that our commercial customers as well as NASA and the United States Air Force have placed in us.
Overview of the incident:
- Yesterday, at SpaceX's Launch Complex 40 at Cape Canaveral Air Force Station, an anomaly took place about eight minutes in advance of a scheduled test firing of a Falcon 9 rocket.
- The anomaly on the pad resulted in the loss of the vehicle.
- This was part of a standard pre-launch static fire to demonstrate the health of the vehicle prior to an eventual launch.
- At the time of the loss, the launch vehicle was vertical and in the process of being fueled for the test. At this time, the data indicates the anomaly originated around the upper stage liquid oxygen tank. Per standard operating procedure, all personnel were clear of the pad. There were no injuries.
To identify the root cause of the anomaly, SpaceX began its investigation immediately after the loss, consistent with accident investigation plans prepared for such a contingency. These plans include the preservation of all possible evidence and the assembly of an Accident Investigation Team, with oversight by the Federal Aviation Administration and participation by NASA, the United States Air Force and other industry experts. We are currently in the early process of reviewing approximately 3000 channels of telemetry and video data covering a time period of just 35-55 milliseconds.
As for the Launch Pad itself, our teams are now investigating the status of SLC-40. The pad clearly incurred damage, but the scope has yet to be fully determined. We will share more data as it becomes available. SpaceX currently operates 3 launch pads – 2 in Florida and 1 in California at Vandenberg Air Force Base. SpaceX's other launch sites were not affected by yesterday's events. Space Launch Complex 4E at Vandenberg Air Force Base is in the final stages of an operational upgrade and Launch Complex 39A at Kennedy Space Center remains on schedule to be operational in November. Both pads are capable of supporting Falcon 9 and Falcon Heavy launches. We are confident the two launch pads can support our return to flight and fulfill our upcoming manifest needs.
Again, our number one priority is to safely and reliably return to flight for our customers, as well as to take all the necessary steps to ensure the highest possible levels of safety for future crewed missions with the Falcon 9. We will carefully and thoroughly investigate and address this issue.
September 2, 9:00am EDT
Statement from SpaceX President and COO, Gwynne Shotwell:
“We deeply regret the loss of Amos-6. Our number one priority is to safely and reliably return to flight for our customers, and we will carefully investigate and address this issue. We are grateful for the continued support that our customers have expressed to us.”
"35-55 milliseconds." Hmmmmm .... the fire triangle : fuel, oxygen and a hot thing. We have the first two ( redox, various ) by the ton & so what was the hot thing, the hot thing that happened to trigger the rest ?
Grumpy, Mike
( edit ) For a 0.04 second interval ( 1/25th of a second ) b/w the last good frame and the first bad one ( the Veteran's video ) the apparent fireball width would have to be more than ~ 0.38 of the height ( 26.4 / 68.4 ) of the launch vehicle ( with fairing ) to be supersonic. Not so, by my eye :
.... but that's going by the visible flame edges. BTW 330 m/s divided by 25 = 13.6 which doubled to 26.4 gives the fireball edge to edge width if at Mach 1, 68.4m is the published height with commercial payload ( with fairing ). On the graphic I've been more generous with fireball width and less generous with Falcon 9 height, and it still doesn't make it IMHO. But the framerate only brackets the possibilities anyway. Why am I thinking of 'detonation' ? Because it's an Israeli payload on a US rocket ..... but I guess we shouldn't go there. Mind you plenty of things detonate, any the fuel/air charge really.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
Mike, the pad being in the USA it is much more likely to be NTSC video at 30 frames per second than PAL video at 25 frames per second. However as it seems to be available in several formats, by the time we see it, it has been through several conversions, compression and uncompressed. I wouldn't put too much stock in them being exact. Much rather see the raw from the camera to make estimates.
Mike, the pad being in the USA it is much more likely to be NTSC video at 30 frames per second than PAL video at 25 frames per second. However as it seems to be available in several formats, by the time we see it, it has been through several conversions, compression and uncompressed. I wouldn't put too much stock in them being exact. Much rather see the raw from the camera to make estimates.
Yeah there's plenty of uncertainty. Just thinking out loud. I think we have another 'non-obvious' problem. What's your take ?
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
I looked at the video again and to me it appears that the failure occurs between the rocket and the support structure in the "hose" inter connects. It does not appear as though the detonation occurred within the rocket itself. The video seems to have been scrubbed/sanitized because all is ok then all is not ok. At 30+frames per second the video should allow for greater detail within a 1 second gap and I am not seeing it.
So they need to fuel the
)
So they need to fuel the second stage to test the first stage engines.
I get it, they need the extra weight so the clamps hold the rocket in place. Or could they do the test if they ran each of the engines in sequence rather than all at once and get qualified? Or it is a pump test to run full throttle on all at once?
Could be static from flow, could be some employee not cleaning all the seals correctly or the connection not mating perfectly. In any case this is a tough one to lose like that. At least the second stage isn't reuse so it was all new and they can't blame it on reuse.
I sure wouldn't want to be the employee who connected the hoses ...
Good eye Mike. Here are two
)
Good eye Mike. Here are two frames cut from archae86's video link. They are 1 second apart. They seem to support some sort of external malfunction. Not sure that they add more than the pics you posted Mike. I was hoping to capture more frames within the 1 second period that would show the outward expansion of the detonation pt.
When I saw the original video on the local TV it appeared as though someone had put about 30 windings of det-cord around the circumference and hit the plunger.
Interestingly I think
)
Interestingly I think detonation might indeed be a more accurate word ( as opposed to 'ignition' ). I couldn't say without more exact timing & distances but if the edge of that blast front is moving faster than the speed of sound ( 330 m/s ) then ideas about causation change c/w subsonic ....
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
Gary Charpentier wrote:So
)
Not really, but "Test as you fly" is a doctrine. They don't reason through the necessity of each particular bit.
As it happens, most folks don't do hot-fire tests with the payload in place. And apparently for SpaceX doing it that way was not firmly a consequence of doctrine, but considerably for wanting to shave a day off the total sequence.
Considering that at SpaceX launch prices it is probably quite common for the payload to cost more than the launch vehicle, someone may push back on this particular bit of improvement.
archae86 wrote:someone may
)
Yes. Definitely. Israel Aerospace Industries tendered the Amos 6 contract at ~ $200M USD. Ouch.
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
I've been looping the video
)
I've been looping the video at highest resolution on my big LED TV. Thoughts :
- that's a minimum 1/2 billion dollar loss to SpaceX, direct/indirect/etc.
- the craft wasn't fully fueled. Sounds odd to say but the explosion was too small & the damage too limited. A complete load ought have flattened the entire complex plus margin.
- the ongoing explosions at ground level tried to track to the right along feed lines but fortunately didn't make it ( no doubt suitable valves cut in ) to the big LOX sphere. Whew !
- there was an apparent change in the upper stage venting about 25 seconds prior to explosion.
Cheers, Mike.
( edit )
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
Quote:September 2, 6:45pm
)
"35-55 milliseconds." Hmmmmm .... the fire triangle : fuel, oxygen and a hot thing. We have the first two ( redox, various ) by the ton & so what was the hot thing, the hot thing that happened to trigger the rest ?
Grumpy, Mike
( edit ) For a 0.04 second interval ( 1/25th of a second ) b/w the last good frame and the first bad one ( the Veteran's video ) the apparent fireball width would have to be more than ~ 0.38 of the height ( 26.4 / 68.4 ) of the launch vehicle ( with fairing ) to be supersonic. Not so, by my eye :
.... but that's going by the visible flame edges. BTW 330 m/s divided by 25 = 13.6 which doubled to 26.4 gives the fireball edge to edge width if at Mach 1, 68.4m is the published height with commercial payload ( with fairing ). On the graphic I've been more generous with fireball width and less generous with Falcon 9 height, and it still doesn't make it IMHO. But the framerate only brackets the possibilities anyway. Why am I thinking of 'detonation' ? Because it's an Israeli payload on a US rocket ..... but I guess we shouldn't go there. Mind you plenty of things detonate, any the fuel/air charge really.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
Mike, the pad being in the
)
Mike, the pad being in the USA it is much more likely to be NTSC video at 30 frames per second than PAL video at 25 frames per second. However as it seems to be available in several formats, by the time we see it, it has been through several conversions, compression and uncompressed. I wouldn't put too much stock in them being exact. Much rather see the raw from the camera to make estimates.
Gary Charpentier wrote:Mike,
)
Yeah there's plenty of uncertainty. Just thinking out loud. I think we have another 'non-obvious' problem. What's your take ?
Cheers, Mike.
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
I looked at the video again
)
I looked at the video again and to me it appears that the failure occurs between the rocket and the support structure in the "hose" inter connects. It does not appear as though the detonation occurred within the rocket itself. The video seems to have been scrubbed/sanitized because all is ok then all is not ok. At 30+frames per second the video should allow for greater detail within a 1 second gap and I am not seeing it.