mersenneforum.org

mersenneforum.org (https://www.mersenneforum.org/index.php)
-   Lounge (https://www.mersenneforum.org/forumdisplay.php?f=7)
-   -   What "weed need" is a space mission! (https://www.mersenneforum.org/showthread.php?t=17609)

only_human 2015-07-01 06:39

[QUOTE=Dubslow;405077]Wasn't the rocket (and stage 1) deliberately exploded (either by a computer or the range officer)?[/QUOTE]
I don't [strike]think so[/strike] know:
[url]https://en.wikipedia.org/wiki/SpaceX_CRS-7#Launch_failure[/url]
[QUOTE]Launch failure

The vehicle's second stage failed with a measured overpressure at T+02:19, well after max Q (at T+01:26[11]) and before first stage engine shutdown (MECO, scheduled at T+02:45).[11] The second stage developed a very large LOX leak, releasing large clouds of vapor while the first stage continued to thrust stably on course for about 9 seconds, until it disintegrated at T+02:28. Aircraft were sent to the debris area in the Atlantic Ocean and an investigation is ongoing.[12][13] It was the first Falcon 9 failure in the 19 launches of the rocket type.[14] According to the founder of SpaceX, Elon Musk, "[The] Falcon 9 [launch vehicle] experienced a problem shortly before first stage shutdown. Will provide more info as soon as we review the data."[15] He added: "There was an overpressure event in the upper stage liquid oxygen tank. Data suggests counterintuitive cause."[16]

It is not clear if the destruction of the first stage was due to the flight termination system.[17] If so, it would have been activated automatically by on-board sensors. The Eastern Range's range safety officer did transmit a remote destruct signal, but only as a formality; sent 70 seconds after the mishap, there was nothing left to destroy.[18][/QUOTE]

Dubslow 2015-07-01 07:06

Interesting. It seems unlikely to me that after flying just fine for 9 seconds with a lox leak something would spontaneously cause an explosion. I find it more likely that something like critically low lox pressure or plausibly guidance thruster fuel exhaustion or something would cause the termination system to trigger. Then again, that's only speculation and guessing.

only_human 2015-07-01 07:15

I've read a couple of comments that the lox pressure is also used for structural reinforcement; if true then then depressuring would lead to structural vulnerabilities.

chalsall 2015-07-02 20:01

[QUOTE=only_human;405080]I've read a couple of comments that the lox pressure is also used for structural reinforcement; if true then then depressuring would lead to structural vulnerabilities.[/QUOTE]

But, this was an over pressure event in the second stage's O[SUB]2[/SUB] tank (according to Musk's Tweet).

Again, watch the video carefully. First there is much plumage (beautiful plumage) from the second stage, then there is an explosion in the second stage. You can see the Dragon fall off the stack after the second stage exploded.

The first stage continued to do its job until it decided things weren't going well and (for safety reasons) committed suicide.

only_human 2015-07-02 20:34

[QUOTE=chalsall;405172]But, this was an over pressure event in the second stage's O[SUB]2[/SUB] tank (according to Musk's Tweet).

Again, watch the video carefully. First there is much plumage (beautiful plumage) from the second stage, then there is an explosion in the second stage. You can see the Dragon fall off the stack after the second stage exploded.

The first stage continued to do its job until it decided things weren't going well and (for safety reasons) committed suicide.[/QUOTE]This sounds persuasive and I would also like to think that a safety destruction operation did occur.

Lets hope Friday's resupply mission goes well and lowers the tension on the situation.
[URL="http://www.cbsnews.com/news/russians-prep-cargo-ship-for-launch-to-space-station/"]Russian cargo ship set for critical space station supply run[/URL]

firejuggler 2015-07-02 21:11

pluto, in colors...
she's like a rainbow... colors everywhere...
[url]http://www.slate.com/blogs/bad_astronomy/2015/07/02/pluto_curioser_and_curioser.html[/url]

only_human 2015-07-03 06:08

[URL="http://www.nasaspaceflight.com/2015/07/russian-progress-m-28-vehicle-cargo-run/"]Russian Progress M-28M launches on critical ISS cargo run[/URL]
[QUOTE]This latest Progress rode to orbit on the Soyuz-U carrier rocket from the PU-5 LC1 ‘Gagarinskiy Start’ (17P32-5) launch complex at the famous Baikonur Cosmodrome.

The switch back to the Soyuz-U removed the main concern relating to the Progress M-27M loss, given that is has since been noted the failure was specific to the Soyuz 2-1A.

The mission also saw a return to the traditional rendezvous timeline after it became impossible for Progress M-28M to rendezvous with ISS using of four-orbit profile without a changing the launch date.

This is due to ballistic reasons, given the ISS could not provide a necessary phase angle between ISS and Progress during this current period.

As such, the Progress will arrive at the Pirs docking compartment in the early hours of Sunday, bringing with it more than three tons of food, fuel and supplies.

The vehicle will be greeted by Commander Gennady Padalka, Mikhail Kornienko and NASA astronaut Scott Kelly. It is also understood this rendezvous will be recorded for an IMAX film.

The ISS will also gain a supply boost from the next Japanese HTV vehicle. HTV-5 is due for launch on August 16, when it is scheduled to depart from the Tanegashima Space Center.

Its four-day trip to the station will conclude when it’s grappled and berthed to the Earth-facing side of the Harmony node.[/QUOTE]

chalsall 2015-07-15 00:59

Looks like New Horizons did it!
 
All systems nominal!!! :tu:

only_human 2015-07-15 02:06

[QUOTE=chalsall;405893]All systems nominal!!! :tu:[/QUOTE]
That's good. The recent spate of private launch failures was unnerving especially since there are scheduled US commercial launches of astronauts as early as 2017:
[URL="http://www.universetoday.com/121271/nasa-names-four-astronauts-for-first-boeing-spacex-u-s-commercial-spaceflights/"]NASA Names Four Astronauts for First Boeing, SpaceX U.S. Commercial Spaceflights[/URL]
[QUOTE]NASA today (July 9) named the first four astronauts who will fly on the first U.S. commercial spaceflights in private crew transportation vehicles being built by Boeing and SpaceX – marking a major milestone towards restoring American human launches to U.S. soil as soon as mid-2017, if all goes well.

The four astronauts chosen are all veterans of flights on NASA’s Space Shuttles and to the International Space Station (ISS); Robert Behnken, Eric Boe, Douglas Hurley and Sunita Williams. They now form the core of NASA’s commercial crew astronaut corps eligible for the maiden test flights on board the Boeing CST-100 and Crew Dragon astronaut capsules.[/QUOTE]

firejuggler 2015-07-15 07:26

[QUOTE=chalsall;405893]All systems nominal!!! :tu:[/QUOTE]

That make me happy.

VictordeHolland 2015-07-15 09:41

[QUOTE=chalsall;405893]All systems nominal!!! :tu:[/QUOTE]
The scientists will have to wait till the end of 2016 before all the data from the Pluto encounter is transmitted back to earth. Understandable at a transmissionrate of 1kb/s.

I was surprised by the details in the images presented so far, considering the distance from the Sun.


All times are UTC. The time now is 23:20.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.