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-   -   Explosion at kennedy Space Center (https://www.pprune.org/space-flight-operations/583815-explosion-kennedy-space-center.html)

pubsman 1st September 2016 14:05

Explosion at kennedy Space Center
 
BBC just reporting explosion at SpaceX launch site:


SpaceX rocket: Explosion at Kennedy Space Center ahead of launch - BBC News

MG23 1st September 2016 14:25

That sucks. But it seems to have happened during a live-fire engine test, so no-one would have been nearby at the time.

cjhants 1st September 2016 15:12

I was in Titusville about 15-20 years ago when one exploded, heck of a bang.

MG23 1st September 2016 15:13

I remember the NASA study on the effects of a Saturn V exploding on the pad or early in the launch being quite impressive. Pretty sure it's downloadable from NTRS.

wiggy 1st September 2016 15:33

The Saturn V paper is here (pdf):

http://www.collectspace.com/review/SaturnVFireball.pdf

Just shows that man was put on the moon in part by photocopiers and staplers...

At least one Apollo astronaut (?Collins) noticed and commented on how few technicians there were around the pad area when they arrived on launch day vs. the other days they went there pre-launch.

Of course on launch day the vehicle was fully fuelled..........

msbbarratt 1st September 2016 18:07


At least one Apollo astronaut (?Collins) noticed and commented on how few technicians there were around the pad area when they arrived on launch day vs. the other days they went there pre-launch.
Sitting on top of hundreds of thousands of pounds of fuel contained by a rocket built by the cheapest contractor...

tdracer 1st September 2016 18:52

Pretty good rundown here:
A Rocket Just Exploded on SpaceX's Launch Pad

Herod 1st September 2016 19:56

My wife's on holiday about 35 miles away (some get Florida, some get Essex), and she heard the explosion. Certainly looks impressive on that link.

11Fan 1st September 2016 20:16

Somebody's gonna get "Unfriended"

The blast took with it Facebook’s first satellite costing the company a whopping £150 million.
https://www.thesun.co.uk/news/171096...spacex-rocket/

Loose rivets 1st September 2016 20:21

I can't stop frame the first part of the flash. The ball of fire is either not there or there.

I'm surprised at the location of the explosion, and equally surprised at the extent of what I assume is a flow of burning fuel from the top.

finfly1 1st September 2016 20:23

Gotta admit, not too upset over fbook not having a satellite, regardless of their stated purpose.

Needle Knocker 1st September 2016 20:25

I wonder if it's possible to insure payloads against disasters like that? And if so, what the premium would be?

Noxegon 1st September 2016 20:43

From the article:


CBS reports that the AMOS-6 satellite lost in the explosion was valued at $195 million. The satellite was going to be used by Facebook to provide internet services from space. Because the incident occurred during refueling rather than ignition, Space News reports that the losses will not be covered by launch insurance.
They can afford it...

LGW Vulture 1st September 2016 21:05

It surely can't take them too long to ascertain what the problem was? I mean for Christ's sake, it's not Rocket Scie.......OH! Sorry.

JerseySean 1st September 2016 21:22


Originally Posted by Needle Knocker (Post 9493832)
I wonder if it's possible to insure payloads against disasters like that? And if so, what the premium would be?

Of course for a premium by some margin less than the value of the payload. That's how insurance works.

Jet Jockey A4 1st September 2016 21:45

Video of the actual explosion...

It happened during the refuelling.

http://abcnews.go.com/Technology/video-captures-spacex-rocket-explosion-launch-site/story?id=41803090

Needle Knocker 2nd September 2016 01:05


Originally Posted by JerseySean (Post 9493877)
Of course for a premium by some margin less than the value of the payload. That's how insurance works.

They like to have the odds stacked in their favour, on average though -- and I'm wondering how risky they perceive this type of thing to be?

onetrack 2nd September 2016 02:47

Thank whatever God you worship, that Farcebook has been stymied in its extension into Outer Space.

What a shame that a large number of Farcebook servers weren't blown up in the rocket explosion as well.

I am glad to hear that there were no injuries, and the losses were only financial.

Needle Knocker 2nd September 2016 03:17


Originally Posted by onetrack (Post 9494072)
What a shame that a large number of Farcebook servers weren't blown up in the rocket explosion as well.

I disagree - Facebook is an incredible business tool. Anyone who thinks it's just for teenagers posting photos of what they had for dinner and parents posting videos of cute cats hasn't got it configured correctly for them.

Huck 2nd September 2016 03:46

I agree. It's a very efficient way to keep up with friends and family on the road.

tartare 2nd September 2016 04:49

Jeez - just read that Saturn V paper - thanks for posting Wiggy.
Now that would have been one helluva bang!
Did I read right - 33 secs duration, 1400ft diameter, 1 atmosphere of over pressure at 2500 dg F!
Mental image of beehive hair-do-ed gal typing out report, authored by white short sleeved shirt, skinny black tied, horn-rimmed glasses rocket scientist.
With short back & sides, and pen protector of course.
Have seen that quote before but still love it... cheapest govt contractor.:)

timcook 2nd September 2016 06:30

When reporters asked astronaut Alan Shepard what he thought about as he sat atop the Redstone rocket, waiting for liftoff, he replied: "The fact that every part of this ship was built by the low bidder"

Joe_K 2nd September 2016 06:58


Quote:
The blast took with it Facebook’s first satellite costing the company a whopping £150 million.
https://www.thesun.co.uk/news/171096...spacex-rocket/
Blimey, that dirtrag of a so called newspaper can't even get basic facts right. Facebook did not own that satellite, hence Facebook did not loose any money. The satellite was owned by an Israeli company called Spacecom. Facebook was merely leasing bandwidth. :ugh:

papazulu 2nd September 2016 07:22


Originally Posted by onetrack (Post 9494072)
Thank whatever God you worship, that Farcebook has been stymied in its extension into Outer Space.

What a shame that a large number of Farcebook servers weren't blown up in the rocket explosion as well.

I am glad to hear that there were no injuries, and the losses were only financial.

Subscribing to FB o oning a profile isn't some kind of a bad-tasting medicine that you GP asks you to take inorder to save your life, you know? Chillax man, wiping off the servers might also have some consequences on people employed to look after them...

Needle Knocker 2nd September 2016 08:49

Keeping in mind too ...

- Where does our SLF post those holiday snaps that inspire their friends and associates to travel with us? Facebook (and instagram -- same company)

- Where do the travel bloggers post links to their videos, photos, and blogs that promote travel? Facebook.

- Where do the travel agents post advertising promoting their services? Facebook

- Where do our airlines post advertising to promote their services on their websites? Facebook.

- Where do businesses start their advertising? Facebook.

Facebook offers incredibly targeted advertising - without it I suspect that more than a few of us would be out of a job due to decreased demand for bums on seats.

Tech Guy 2nd September 2016 11:22

Should be some good overtime prospects for the engineers at the satellite building plant. :)

falcon12 2nd September 2016 12:10

USA aviation sources are indicating it was being fueled and LOX was involved

601 2nd September 2016 12:24

How do crooks know when and where you will be when travelling, on which flight and to which destination for one of those wonderful holidays all found on F@(Eb00K ??

jxf63 2nd September 2016 12:40

Well, in my case, they know where I've been but never where I am or will be ;)

deSitter 2nd September 2016 14:36

In the USLaunchReport video (see link below), there is about a 5.5 second delay between what is seen and what is heard - the camera is about 1.5 miles away. About 5 seconds before the report of the initial explosion, there is a very large bang sound, like someone striking a garbage pail with a hammer. The sound clearly originates in the distance, something that is made more likely by the fact that the launch site and surround would have been basically abandoned for a live fire test.

Now, visually, there is no event at the launch site that corresponds to this loud sound. It would have come at about 1:06, 5 seconds before the explosion. What could make such a large noise yet leave no visual record?

Some time ago, the SpaceX Falcon 9 CRS-7 mission failed when, just as in this case, the 2nd stage LOX tank failed during flight. The helium pressurization for these 2nd stage LOX tanks is derived from a smaller vessel that is actually housed within the tank and secured to it with steel struts. When the LOX tank is full, there is a large buoyant force on this vessel, like a football held under water, and this puts great stress on the support infrastructure. The in-flight failure was caused by failure of the securing struts, at which point the now-free helium vessel rocketed (ha) to the surface of the liquid oxygen pool and slammed into the LOX tank wall, fatally weakening it.

It seems possible that the loud noise heard on the video is the audible report of the same event. 5 seconds later, the tank fails.

https://www.youtube.com/watch?v=_BgJEXQkjNQ

deSitter 2nd September 2016 14:53

The oxygen storage tanks at the Cape seen in old films have giant black LOX letters painted on them. LOX has been used in space flight to mean liquefied oxygen for many decade

wiggy 2nd September 2016 15:03

DeSitter - Agreed.

LOX has been widely used as convenient short hand for straightforward unadulterated liquid oxygen in the spaceflight industry for decades so I don't think this is a case of the journalists getting it wrong.

If you have a look towards the back of the NASA technical paper on fireballs I linked to a few posts back you'll see "LOX" used both in one of the references and also in the graphs....

Airbubba 2nd September 2016 15:03


Originally Posted by deSitter (Post 9494629)
In the USLaunchReport video (see link below), there is about a 5.5 second delay between what is seen and what is heard - the camera is about 2.5 miles away.

That's some mighty fast moving sound if it went 2.5 miles in 5.5 seconds. ;)

Ian W 2nd September 2016 15:08


Originally Posted by 601 (Post 9494490)
How do crooks know when and where you will be when travelling, on which flight and to which destination for one of those wonderful holidays all found on F@(Eb00K ??

Be fair it also saves Advanced Persistent Threats huge amounts of money and time.

MG23 2nd September 2016 15:11


It seems possible that the loud noise heard on the video is the audible report of the same event. 5 seconds later, the tank fails.
However, as I understand it, the in-flight failure was due to acceleration forces, which would be going in the opposite direction to bouyancy. They've put extra effort into checking every single strut since then. and I presume the second stage has been test-fired (and, hence, previously fuelled), like the first.

It's possible it's a related problem, but, from what I've read, the failure seemed to start around the umbilical attachments, which would make them a prime candidate. If it disconnected and started spraying liquid oxygen around, that would have been bad news.

deSitter 2nd September 2016 15:22

1.5 not 2.5 :) typo oops

Scuffers 2nd September 2016 15:34

the big explosion was the satellite hitting the ground and it's ~2 tonnes of hypergolic fuel exploding.

the initial flash-fire looks like it's from outside the second stage where the LOX umbilical is connected.

one can only speculate that either there was a failure in the umbilical/coupling or some contaminate came into contact with the O2 venting, a lot of things get very incendiary in a pure O2 environment.

deSitter 2nd September 2016 15:39

There are three main explosive reports in the initial event 1) the initial tank rupture 2) a much larger report 3 seconds later, possibly from the RSO operating the self-destruct mechanism and 3) the report from the satellite stage toppling to the ground about 11 seconds after the first report.

2EggOmelette 2nd September 2016 19:55

Nicely spotted AirBubba! I counted 12 seconds from flash to bang on the video myself though. So at 340.3 m/s at sea level (I assumed sea level as I have no idea of the elevation there) it makes 2.2 NM (2.5 statute). Looks like that cheeky speed of sound was sticking to the rules after all ;-)

CONSO 2nd September 2016 22:00

Pad was within say 50 feet above sea level. But speed of sound is a function of temperature- not pressure/altitude


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