Launch News SpaceX Falcon 9 F4 CRS SpX-1 Updates

[MattBaker]

All the debris flying around in the slow-motion don't look like an shut-down:shifty:.

Fourth flight, first engine failure inflight, would make a 1:40 probability, let's hope that's that high because of the low number of launches...

 

[Hlynkacg]

well they did a crap job of it then didn't they

They would have yu believe that having 111.12 km be one degree of latitude (or longitude at the equator) is simpler than 60 nm.

 

[N_Molson]

Interesting. Again that suggests that the "lots of small engines" approach is not that safe. Of course there are not enough flights to draw hastily conclusions. Clearly this is not a simple controlled shutdown, something blew off, and it seems to come from engine #1.

The very good thing is that the rocket itself was able to sustain the apparently serious damage and still deliver the payload to orbit. Good design here, it seems that each engine is pretty well isolated from the others. With a manned crew, the abort system could have been safely triggered.

Now, several uneventful launches will be required to achieve man-rating, I guess.


About nautical miles in spaceflight : nonsense. Firstly, tidal effects make that 1° of longitude or latitude is not a constant. Secondly, this loses any kind of sense when you are, let's say, on Mars. Or make Martian Nautical Miles (Mnm). Nautical miles are interesting for sailing or aviation, when you are on or not far from the surface. Thirdly, the meter is an universal SI unit, and has the great advantage to be convertible with multiples of 10 (millimeters, centimeters, decimeters, meters, decameters, hectometers, kilometers...), which makes the maths way easier !

 

[MattBaker]

Interesting. Again that suggests that the "lots of small engines" approach is not that safe. Of course there are not enough flights to draw hastily conclusions. Clearly this is not a simple controlled shutdown, something blew off, and it seems to come from engine #1.

On the other hand you could say: "This event proves that one engine failure can't fail your whole mission, so launching with the Falcon Heavy is as safe as the SLS!" Although I think they just had luck probably, additionally it's engine 1, if engine 5 will blow up...

Now, several uneventful launches will be required to achieve man-rating, I guess.

I fear that this will end up in a congressial-bashing of private spaceflight/SpaceX, luckily CCiCap is already awarded, otherwise SpaceX could face serious problems (Boeing already had better ratings in safety before, now with that event?)

 

[Hlynkacg]

Interesting. Again that suggests that the "lots of small engines" approach is not that safe. Of course there are not enough flights to draw hastily conclusions. Clearly this is not a simple controlled shutdown, something blew off, and it seems to come from engine #1.

The very good thing is that the rocket itself was able to sustain the apparently serious damage and still deliver the payload to orbit. Good design here, it seems that each engine is pretty well isolated from the others. With a manned crew, the abort system could have been safely triggered.

Now, several uneventful launches will be required to achieve man-rating, I guess.

Why would this event trigger an abort, or effect "man-rating"?

About nautical miles in spaceflight : nonsense. Firstly, tidal effects make that 1° of longitude or latitude is not a constant. Secondly, this loses any kind of sense when you are, let's say, on Mars. Or make Martian Nautical Miles (Mnm). Nautical miles are interesting for sailing or aviation, when you are on or not far from the surface. Thirdly, the meter is an universal SI unit, and has the great advantage to be convertible with multiples of 10 (millimeters, centimeters, decimeters, meters, decameters, hectometers, kilometers...), which makes the maths way easier !

Oh for cryin out loud why does every take this so seriously?

But for your information making the maths easier is why nautical miles are used in the first place. The Nautical Mile is derived from the "knot" wich is your Lat/Long's rate of change. Afterall when it comes to navigation velocity is irrelevant what you're really calculating is Delta P.

On Earth one arc minute an hour (due north or south) is roughly 1.825 kph. Thus we get the 1825 meter nautical mile

On Mars one arc minute an hour would be 0.998 kph making a nautical mile on Mars (almost) equal to kilometer proving that the lizard people who created the metric system originated on Mars :shifty:

 

[MattBaker]

Why would this event trigger an abort, or effect "man-rating"?

Well, if one of the debris impacts the fuel tank, another engine chamber or something like that you could end up with Challenger: Rocket Edition, as I stated before I think that an explosion like that in Engine 5 would end in something like that.
So if there are humans in the Dragon and you don't want to put their lifes at stake you should better abort than being sorry afterwards.

And man-rating is all about reliability, no one would man-rate the KSLV or the Unha of the Koreas, simply because they blow up too often. The same effect could happen to the Falcon, no one will man-rate a rocket that plays kerbal every fourth launch and risks the life of your astronauts. No offence to anyone who advocates them, but if I should choose between the Falcon ) and the Atlas V to transport me to the ISS, my choice would be the Atlas V.

 

[Kyle]

Never good to loose an engine, but there are 8 other backups It's when you loose 3 or more, then you need to worry.

 

[Urwumpe]

But the creators of the metric system were idiots when they created Kilometers that did not divide evenly into degrees of Latitude.

Thus Knots and Nautical miles are here to stay.

Only exactly on the poles. Not somewhere else. Which is, sadly, most of the planet.

In 1700, nautical miles was really a huge improvement over all possible alternatives, since GPS, VOR, TACAN or INS did not exist back then. Today it is pretty antique. But still better than the US units for mass, weight and volume.

---------- Post added at 03:53 PM ---------- Previous post was at 03:47 PM ----------

Well, if one of the debris impacts the fuel tank, another engine chamber or something like that you could end up with Challenger: Rocket Edition, as I stated before I think that an explosion like that in Engine 5 would end in something like that.
So if there are humans in the Dragon and you don't want to put their lifes at stake you should better abort than being sorry afterwards.

Still can be prevented by ballistic blankets between the engines, proper placement of prevalves and the use of low energy density rocket engines. The turbines of the Merlin are still magnitudes less powerful than the turbines of a SSME. When a Merlin engine explodes, its a small bang. When a SSME HPOTP explodes, it's a real big bang. Hydrogen rich exhaust mixing with gaseous oxygen, Titan reaching the temperature at which it reacts to Titanoxide, etc... not nice. Thus the expensive effort into preventing explosions in first place, by expensive maintenance and expensive health monitoring computers.

The Merlin engine is a lot different in that aspect, its failure could really be isolated to affect only one engine.But if you have problems getting the problem automatically isolated from the rest of the spacecraft, you should really abort ASAP.

---------- Post added at 03:58 PM ---------- Previous post was at 03:53 PM ----------

All the debris flying around in the slow-motion don't look like an shut-down:shifty:.

Fourth flight, first engine failure inflight, would make a 1:40 probability, let's hope that's that high because of the low number of launches...

You don't want to know how it would look without shutdown sequence already in progress. Maybe it was a piece of the nozzle or an overheated injector failure, there are many possibilities, one part there looked like the aerodynamic fairing of the engine compartment. Very likely a turbine failure by the slow-motion, though this isn't the cause, only the symptom.

Also about reliability, remember the bathtub curve. In the beginning and towards the end of the lifecycle, you have most problems, between it you have a low plateau. Just look at the early failures of the Ariane 5. No comparison to today.

 

[RisingFury]

I'm quite impressed by F9's ability to lose an engine and continue as if nothing happened :thumbup:

Any kind of "If this happened to engine 5..." is just speculation. We don't even know what happened beyond the fact that it happened to engine 1...

 

[N_Molson]

Why would this event trigger an abort, or effect "man-rating"?

Well, my idea is that we're not in the 60's space race anymore - especially in the perspective of "routine" commercial ferry flights to the ISS - and that an ultra-careful policy would probably be applied. Challenger & Columbia also contributed to that "super-careful" approach of manned spaceflight : a slight and apparently harmless defect on an insulation foam can lead to a catastrophic failure.

Well anyway lets wait a more detailed report on that engine failure. As I wrote it is too early to draw general conclusion (don't say I didn't wrote it).

Thus we get the 1825 meter nautical mile

Actually it is 1852 meters. And again, when sailing, I have nothing against nautical miles. But for spaceflight, well...

 

[Cosmic Penguin]

Updates, where are you?

:goodnight: (yawns at the lack of updates on this flight, not even the mission-critical opening of the guidance and navigation sensor bay door of the Dragon, which was supposed to happen half a day ago; or the status of the secondary payload of this flight, which I believe was put into a lower than planned orbit close to that of the Dragon due to a possible abort with the Falcon upper stage, as shown by US tracking data)

Actually I already felt something fishy during the live coverage of the launch (I did not notice the problems until much later): before launch the mood was just like the last few missions (a.k.a. SpaceX party mode), but somehow it seems the tension has rise during second stage ascent, with SpaceX engineers starting to walk around the room for no reason (one even "bounced" off his seat, as if he was seeing something horrific). Then at T+7.5 minutes the velocity was given as 4.9 km/s - which sounds rather slow, and I was thinking if something went wrong. Then came SECO-1 and the announcement of the orbit, then Dragon separation. But instead of cheers that I had expected, there was nothing. And after the deployment of the solar arrays (remember that the whole Hawthorne cheered last time at this point? There wasn't much heard on the public channels this time), the live coverage at SpaceX ended rather quickly - not something I would had expect for the first ever commercial orbital cargo-resupply flight. When the SpaceX PAO removed the launch video on Youtube minutes after he/she put it on, I knew something was wrong...

Eerie, isn't it? :uhh:

Edit: I once complained that the only place you would have a harder time to dig out technical details of a rocket than the Chinese is SpaceX. Now it looks like this also holds true of mission live updates: nothing about the Dragon has been released since Dragon separation. :facepalm:

 

[Ark]

Edit: I once complained that the only place you would have a harder time to dig out technical details of a rocket than the Chinese is SpaceX. Now it looks like this also holds true of mission live updates: nothing about the Dragon has been released since Dragon separation. :facepalm:

Welcome to the world of private spaceflight, patents and non-disclosure agreements for everyone!

 

[T.Neo]

Pretty interesting that a vehicle suffers an engine failure (seemingly a rather violent one) yet still (seemingly) carries its payload to orbit safely, and this is taken as an indication that the vehicle is unreliable...

Also, simply because a failure occurs does not mean that things have suddenly become more unsafe than they were previously- the failure has just brought attention to a flaw that has likely been around for some time. In the wake of incidents like that, safety does not degrade- it improves as people gain a better understanding of those issues, and how to prevent such failures from occuring again.

 

[MattBaker]

I have to agree with you, especially the missing cheers bugged me.

But what's the media coverage of governmental missions like? Launch, Separation, Approach, Docking. But of course, SpaceX is not the government and if you compare it to the coverage in May...
In the post launch press conference (which you can see by the way here, I think no one posted that yet) Mrs Shotwell talked about an update on the engine anomaly tomorrow. So there's probably at least a press release, if not a conference tomorrow, then they will probably talk about everything.

 

[N_Molson]

It's probably a very pessimistic hypothesis but maybe they were short of a few hundred m/s to achieve orbit and had to burn a significant mass of the Dragon's fuel ? Which would explain that the payload made it to orbit while people don't seem too happy (not knowing if they will be able to reach the ISS) ? :hmm:

 

[Cosmic Penguin]

It's probably a very pessimistic hypothesis but maybe they were short of a few hundred m/s to achieve orbit and had to burn a significant mass of the Dragon's fuel ? Which would explain that the payload made it to orbit while people don't seem too happy (not knowing if they will be able to reach the ISS) ? :hmm:

Nah, at the T+10 minutes point (just after SECO-1) there was a report that the orbit achieved is 197 x 328 km, so no performance shortfall for the Dragon. I'm not sure why the second burn didn't took place, but it may be related to the "late orbit insertion" as opposed to running out of fuel (there was a report that the Orbcomm satellite would separated after SECO-1 if certain "health checks" failed).

 

[Cosmic Penguin]

Urgh, can't believe it took 14 hours to confirm this, but finally some good news.... :thumbup:

Dragon's GNC bay door, which houses the craft's rendezvous sensors and grapple fixture, successfully opened as planned last night, according to a SpaceX spokesperson.
The spacecraft uses thermal and optical sensors to navigate in close proximity to the International Space Station, and the grapple fixture is required for the robot arm to grasp the capsule and move it into position on the lab's Harmony module.

http://www.spaceflightnow.com/falcon9/004/status.html

(then again, I don't know that today is Columbus Day in the US and Thanksgiving in Canada LOL :blush

 

[Cosmic Penguin]

A SpaceX statement via Ars Technica:

Approximately one minute and 19 seconds into last night’s launch, the Falcon 9 rocket detected an anomaly on one first stage engine. Initial data suggests that one of the rocket’s nine Merlin engines, Engine 1, lost pressure suddenly and an engine shutdown command was issued immediately. We know the engine did not explode, because we continued to receive data from it. Our review indicates that the fairing that protects the engine from aerodynamic loads ruptured due to the engine pressure release, and that none of Falcon 9’s other eight engines were impacted by this event.

As designed, the flight computer then recomputed a new ascent profile in real time to ensure Dragon’s entry into orbit for subsequent rendezvous and berthing with the ISS. This was achieved, and there was no effect on Dragon or the cargo resupply mission.

Falcon 9 did exactly what it was designed to do. Like the Saturn V, which experienced engine loss on two flights, Falcon 9 is designed to handle an engine out situation and still complete its mission.

 

[Urwumpe]

Lost pressure suddenly... could be one of the main propellant ducts bursting, if it was not an explosive failure of the thrust chamber itself. But then very likely no turbine failure, since this would not result in a loss of pressure into the thrust structure, only a drop of pressure by lack of pumping.

 

[Mandella]

Pieces keep falling off that thing, they're going to have to rename it Serenity...

:lol: