SpaceX CRS-5 Launch Delayed
UPDATED: SpaceX Set to Launch NASA CRS-5 Resupply Mission to the ISS, SpaceRef Business
“Launching from Cape Canaveral Air Force Station, Fla. the SpaceX Commercial Resupply Services Flight (CRS-5) will deliver cargo and crew supplies to the International Space Station. It will also carry CATS, a laser instrument to measure clouds and the location and distribution of pollution, dust, smoke, and other particulates in the atmosphere.”
Keith’s note This morning’s launch attempt was aborted shortly before launch. Since this was an instantaneous window opportunity there won’t be another attempt today. The next attempt will be no earlier than Friday at 5:09 am ET. SpaceX was quietly working an actuator issue last night. No word as to whether is is related to this morning’s launch abort although we’re heard reports of an “actuator drift” issue in the Falcon’s Thrust Vector Control (steering) system during today’s countdown attempt.
it’s going to be a long night for those of us on the west coast
And early one for us on the East coast. 🙂 But well worth it.
A small regret that given an ontime launch , the attempted Falcon first stage landing will happen ~40 minutes before local sunrise.
I like the video from launches into the dawn. The way the light catches the engine plumes in vacuum can create beautiful effects.
Okay, boys and girls, this is the proverbial “it”. It’s time to light the candle, orbit the bird and bring that launcher home. If this works, it will be that much harder to laugh at SpaceX and their ambitions.
Space is hard, no matter who is doing it. No matter how long you have been doing it.
“Space is hard” especially when every launch is a brand new vehicle which may have a manufacturing issue that has yet to be discovered. Reusable launch vehicles will make space easier in the long run.
After the abort they said that it was due to an issue on the second stage. I don’t know if they actuator was on the second stage or not.
Musk tweeted Z actuator on the second stage
X wrote on its website. “The first burn — the boostback burn — adjusts
the impact point of the vehicle and is followed by the supersonic retro
propulsion burn that, along with the drag of the atmosphere, slows the
vehicle’s speed from 1300 m/s (2,900 mph) to about 250 m/s (559 mph).
The final burn is the landing burn, during which the legs deploy and the
vehicle’s speed is further reduced to around 2 m/s (4.5 mph).”
Is it a boostback burn? The 1st stage separates at 45 mi. down range. It will land about 200 mi. down range. Are they waiting until it coasts past the landing point, fire while pointing back. While they will need to do this to land back the Cape later, I think it is no boostback burn. They are retro rocket firing enough to arc it over to land. If it is a true boost back some diagrams I have seen need to be changed to show it. It could be just the name and does not actually describe what is happening this time.
There are 3 burns. First is a “boostback” burn that sends the rocket back in the direction of the launch site, later a “reentry” burn (the supersonic retro propulsion burn) that slows the rocket down as it re-enters the atmosphere, and then a final landing burn.
here is a diagram:
http://media2.s-nbcnews.com…
So there are still three burns, but in this case the boostback burn is shorter than it would be to return to land, and instead just stops the eastward movement of the booster and allows it to descend more or less vertically. If we include the launch itself the booster fires four times.
that sounds about right.
there’s an illuminating timeline of events during the CRS-5 launch on spaceflight101, according to which the boost-back burn for this flight is performed after first stage apogee: http://www.spaceflight101.c… (the timeline is about halfway down the page, i will post a screenshot for everyone’s convenience) i would presume that for a return back to the launch site the boost-back burn would be initiated much sooner.
So there is a two minute delay between separation and boost-back ignition. Based on the rough diagram you provided, a similar boostback burn initiated just after separation would put the booster on or near the launch site. Interesting that the booster trajectory is above that of the second stage.
i think the diagram was illustrated as being over the trajectory of the 2nd stage (which of course isn’t horizontal) for clarity / simplicity, the second stage just flies off into orbit so it’s “out of the picture” anyway. the actual trajectory would look something a bit more like this (with an immediate boost back to the launch site):
http://makeyev.ru/userfiles…
So you are saying that even though it is called a boostback, it does not actually at some point come to a dead stop for a second. This would happen if it flips and starts to coast downward and the engine is fired. Or still coasting upwards would be only 50 miles out. Since it is in space it will slow down, then speed back up due to gravity. I wonder where is the best place to fire, considering how much it slows on the way up and how far it has to get back. At separation it is closest, but has the most speed. Also a high launch angle may keep Dragon from reaching the correct altitude. Must be a computer program for that. A good way to look at it is to throw a baseball into the air. Tinkers straight up may be the way to go. No boostback burn needed. Just slow for reentry and use the paddles to line up. No energy needed to boost back. They would go up with just enough angle so that when it falls back it would be in the 10k cross range area. I hope it is possible to go about straight up. It would be the best. Quick thoughts, I may have got something that is wrong.
of course it wouldn’t come to a dead stop at any given time, but its distance relative to a stationary observer on land would stop increasing and begin decreasing at some point.
if you’ll read my post below, the boost-back burn for this flight will take place after apogee.
If they went straight up they would lose the benefits of doing a gravity turn. Eliminating the gravity turn could more than offset whatever fuel savings they would gain by eliminating the boost-back burn of the first stage.
What gravity turn do you mean? Falling straight down, it would not turn and I see no benefit of turning. but would do a reentry burn and a landing burn. There would be a gravity turn in the arc away from shore for safety in case of a destruct. It would be much safer than burnback toward populated area. If it burned too long and then was destructed it would hit a populated area. I may protest doing that and suggest using not exactly straight up method only. I would be close to the ballistic path it might take. I can not believe the range would approve boostback. After officials, media get what they want to do and the dangers, they may not allow their method. My method would be safe. Inertia would keep all debris away. It would have to be very close to landing for a destruct pieces to hurt anything. About the same as a launch. It is fine landing on the ship if the boostback burn is never long enough for pieces to hit me.
Gravity turns are started moments after launch during pitchover and while speed is very low. It takes just a small amount of thrust to start the turn, then they can gimbal back to inline thrust for efficiency, meanwhile gravity will continue the turn that was started basically for free since no thrust is required, and also gravity drag is reduced because some of the gravity component is being used to turn the vehicle. The gravity turn even continues during staging when there is no thrust.
If they launch straight up or nearly straight up as a method of keeping the first stage near the launch site, that puts the entire burden of the turn on the second stage. I guess the second stage could start a gravity turn when it ignites, but I am thinking the benefit would not be as great as starting it shortly after launch. If there is a loss of benefit that would be an offset to the gains of eliminating/reducing boost-back burn.
Your point about flying back towards the coast I agree with. I think the regulatory hurdle over that will be greater than the technical hurdle.
Thanks. That might be the problem. There would be an arc. If the 2nd stage coasted until gravity arced it to the best place to fire, it may still have enough fuel There is always fuel left over after the 2nd burn to circle the orbit. I hope it works and they do it. NASA TV cameras might be able to show a lot of it from KSC. Newtons Laws of Motion says it would be safe.
I’m surprised that they haven’t done even a partial boost-back burn on previous flights, instead they will be attempting it for the first time on the same flight where they will be attempting a landing. Normally they seem to be more incremental in their approach, but maybe they decided that the previous water landing counts as the first successful landing (technically speaking) so in that sense this flight is mainly about trying boost-back for the first time. Although of course from a PR and historic viewpoint all of the attention will be on the landing and recovery of the booster if they are successful.
On that note, what will really be the historic moment is when a stage is successfully used on two different launches. Whether this particular stage will be that historic stage depends of course on a successful recovery, but also on whether SpaceX plans to use this stage on a second flight or keep it for study or as a museum piece.
there have been four soft-splashdown tests, and they did a boost-back burn on both the third and fourth.
http://en.wikipedia.org/wik…
the fourth one they needed to return closer to the coast for the cameras on NASA aircraft to observe the supersonic retropropulsion. the NASA video captured the flip over and the boost-back burn and the retro burn. it’s quite something to watch:
http://youtu.be/_UFjK_CFKgA
It says to control downrange. They might have just retro burned to keep it from going so far downrange. The camera might show different views. I do not see it coming back the way it went.
the wording is weird and kind of vague, so perhaps you are right.
well, the camera’s view is from 50 miles away, and more or less looking downrange in the direction of the launch, so it would be really difficult to “see it coming back the way it went” – kind of like if you were looking at a car a mile away, could you really tell if it were driving towards you or backing up?
Are those actuators tested during launch rehearsal?
Would think so but this was just slow drift. Maybe that’s why they want to look at it again. I think hydraulic pressure only comes up in the terminal count.
Apparently the secod stage engine Z actuator was drifting, i.e. moving slowly in the absence of a control signal. This could be caused by a very small leak in one of the hydraulic valves. The drift could easily be overcome by a small control input; it’s a little like when your alignment is off and you have to maintain a little pressure on the steering wheel to go in a straight line. So it would not (IMO) have caused the vehicle to go off course but I can understand wanting to have everything just right before launch. Still it is not clear whether they will actually fix the system or just analyze whether they can fly with it as is. Next attempt Friday.
SpaceX has commendably routinely operated with a super abundance of caution. The downside of delays is more than balanced by the upside of avoiding failures and their customers have expressed their support for that trade-off.
At most (but not all) times that SpaceX delays a flight they point out that the system is robust enough to fly nominally even if launched. But they choose not to. Good for them.
I wonder which axis the ‘Z’ actuator controls? Normally pitch and yaw are in the XY-plane.
Maybe the actuator’s direction of action is parallel to the Z axis.
mistaking miles and kilometers is a simple mistake, really not all that uncommon, people tend to read distance measurements in the units they are most familiar with
lol. don’t be so silly.
it’s a very common mistake. even the best of us make such errors from time to time. i’m sure if you wanted to inform her of the error, she’d correct it.
Common indeed. Don’t forget the Mars Climate Orbiter. Many years ago full metrication was proposed for the ISS program. NASA turned it down. I know this sounds absurd, but if we all used the metric system we would not have conversion errors.
… so what?
and how long ago is “many years ago”?
anyway, this is irrelevant. NASA is all metric now, and this comment isn’t about NASA.
The U.S. has been slowly moving, inch by inch, toward metrics for decades. 😉
Lololol busted me up 🙂
Are you certain that NASA is all metric?
Yes, by law and by internal policy, NASA uses the metric system. however, they’ve got decades worth of old equipment and data that is in imperial units and so they still have to work with those when they’re there.
in press releases they often provide figures in imperial units because that’s what the general US population is used to.
“NASA is all metric now” is not correct. NASA plans to use metric when possible going forward.
NASA started doing that in about 2001, so yes, now.
http://solarsystem.nasa.gov…
You missed the point of that link. NASA is not all metric now. It is a goal – where it is practical and economically feasible.
For example, the tons of circuit boards used by NASA (and in SLS) are described in mils (1000ths of an inch). Currently. Right now. Tomorrow.
For example: https://www.fbo.gov/index?s…
It is commendable and for any international program extremely important that parts be interchangeable and metric. But that is not there yet.
Part of the problem is that the US aerospace is traditionally English units and NASA has to live in that world.
that, and also because much of the SLS is derived from the Shuttle, which was done in imperial units.
i did not miss the point of that link, and i already knew about NASA using imperial units when it has to, i said as much earlier. and why not? i’ll say it again.
any new NASA project since circa 2001 should be being built with and run in metric units, save that which uses old equipment / designs / data. are you happy now??
you don’t have to take my word for it. here is the text of the current NASA policy:
“Metric System of Measurement. It is NASA policy for all new programs and projects subject to NPR 7120.5 to use the International System of Units (commonly known as the Systeme Internationale (SI) or metric system of measurement) for design, development, and operations; in preference to customary U.S. measurement units, for all internal activities, related NASA procurements, grants, and business activities.”
http://nodis3.gsfc.nasa.gov…
now, if you want to continue to pick at the troubles NASA has metricizing, go right on ahead. no matter what you say, metric is still NASA’s policy – not their policy in their future, it’s their policy now. my statement was correct.
My quibble was with . “NASA is all metric now”, which I see as implying that their physical hardware is all metric – nice as that would be, but isn’t nor will be any time soon.
I have no problem with something like “NASA’s policy is to use metric unless it is unfeasible or uneconomical.”
of course the hardware can’t be all metric. they have 40 or 50 years worth of equipment and documentation that’s mostly done in imperial units.
i forget when, but at some point they did a study that estimated it would take something like $400 million dollars to go through all that and convert everything to metric.
http://www.popsci.com/milit…
There are two types of countries: those that use the metric system and those that have put men on the Moon.
Bravo!
NASA could have used cubits, palms, and furlongs for measurements to get to the Moon. As long as it is consistent. However, not using the standard units used in science everywhere, including the US, and used in engineering and manufacturing essentially everywhere on Earth (including much in the US), and used in common usage everywhere on Earth except the US, affects our efficiency and the desirability of our products.
The modern world runs on binary (and its extension bases) and the decimal system. Using units that make calculating how many square yards in an acre or teaspoons in a gallon is wasteful in so many ways.
As the old binary joke goes: There are 10 kinds of people. Those who use the right units, and those that don’t.
Please don’t be offended by this. I say this in a positive spirit. Quite often you ridicule other posters and their comments. The constant use of “LOL” is usually taken as an insult, or as in this case the direct: “don’t be silly” is a direct insult.
This is supposed to be an enjoyable comment section, not a hostile slam zone.
Just sticking my 2 cents in, unsolicited.
the poster is acting like saying miles when kilometers was meant is some sort of horridly unprofessional and abominable act, which i really don’t think there’s any other way to call that but silly.
i usually only post “LOL” when i actually laugh out loud. in your case, yes, i actually laughed at you. claiming to be objective and factual when your posts reek of political bias is laughable. add to the top of that your inability to post any facts or figures which support your claims… well, it was a night of hilarity for me.
Fine, make it personal. It is harmful to the blog. That it is also detrimental to having people take you seriously is of your concern.
My concern is that flaming never helps a board. You can laugh at me or others all you want. Personally I roll my eyes in dismay at some things you post, but I choose not to to post eye-rolling animated emoticons after your posts. It simply degrades the environment. So do what you need to do.
It ain’t personal. comparing Maricia Dunn to Fred Flintstone because of a simple mistake in units is personal. and it’s silly!
as far as people taking me seriously, that’s something you only get when you post things that are intelligent, insightful, or relevant, and i’ll gladly stand on my general record of posts.
the people here who’ve seen me frequently post can probably tell you – i’ve stuck with the facts so far as I know them, and when i correct people it’s usually because they’re wrong, and if i’m in error, i gladly admit it. how else does one learn?
“is personal. and it’s silly!” You don’t understand the point that the “personal” refers to posters within the board, not comments on public persons. Flaming has nothing to do with whether someone calls Congressman X a moron. If they call Nasawatch poster “XYZ” a moron, then it is destructive.
so… calling out someone who’s behaving in a silly manner upsets you. okay. you need to relax and not be so uptight.
Remember, I am referring to mocking posters internally, not people on the outside. I have been a moderator on message boards and I see the ill effects of mocking and hostility to fun discussion. People don’t like to participate when they fear getting rolled. I don’t let attacks stop me, but it makes the discourse sour. remember, nothing said in these comments have any meaning or effect anywhere in the real world. Its only a place for fun and informative discussion. Name-calling only hurts.
A couple of months ago on nasawatch I was so amazed at what a poster said that I replied with “LOL” and a mocking response. I am heartily unhappy with that lapse, and I issue a general mea culpa for my uncivil behavior.
very well. next time someone makes a comment lambasting someone else for making a trivial mistake, i’ll expect you to deal with it.
I have – repeatedly.
For example: http://nasawatch.com/archiv…
In a project report I wrote I once mistakenly typed nm instead of μm in a number of places. I’m glad my bosses realized it was just a simple mistake instead of crucifying me the way people are crucified online for similar simple mistakes.
I’ve yet to meet a person who’s not committed simple errors as such.
If you want accountability / to point her in the right direction for this mistake, then go ahead and email her and let her know about it. I’m sure she will gladly correct her article, and then thank you for bringing the error to her attention.
I think the reason that people are not reacting to this the way that you seem to be expecting them to is because Marcia Dunn is a seasoned space reporter, when I see her name on the byline I stop and read it because I know it will be a good article. Many people including myself find her articles to be well written, interesting, accurate and informative. Somewhat rare considering the balancing act of trying to make things interesting for the general public while also satisfying people who are knowledgeable about the details and wanting in-depth info. So when we see a typo like this we realize it was the type of mistake anyone can make under a deadline.
If we are going to pick battles about accuracy it should be with reporters who consistently botch up facts out of carelessness because they are more about being entertaining. I don’t see Marcia Dunn as falling into that category so no real need to start a riot about it.
You think her editor would have caught this? Meaning they fact-check every bit of minutia in every story that their space and science reporters write? I would assume that most space and science reporters are only grammar checked by their editors.