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NASA Installing Shocks On Ares
caffiend666 writes "In order to abate the massive vibration issues of their new Ares I spacecraft, NASA is installing shock absorbers. 'The plan is to install 16 canisters in the bottom of the rocket with 100-pound weights attached to springs. Battery-powered motors will move the weights up and down to stop vibrations. Those are essentially remote-controlled shock absorbers, said Garry Lyles, who headed the team of NASA engineers tackling the shaking problem.' So, when the spaceship is a rocking, don't come a knocking?"
Whilst I'm not overly surprised by the decision why have they left it this late, as its a well documented problem thats been around since the beginning of space flight.
No, they are dampening the vibrations because vibrations from SRBs are too unpredictable to be canceled out in the way you describe.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
Here's a picture of it.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
Their demise wasn't caused by a flaw in the rocket itself, it was because the capsule was using pure oxygen under low pressure in order to save weight.
Unfortunately - materials that were flame-retardant or flameproof in normal air became extremely volatile in the 100% oxygen atmosphere in the capsule. They changed to a different mixture after that accident.
Their accident also happened while on the ground during a test and not in space. Their accident was actually to honor them being designated Apollo 1. (as from what I have understood from at least one source, other sources does claim that it already was designated Apollo 1). So the only in flight accident with the Apollo program was Apollo 13 - and they did survive.
So this actually tells us - beware us from accountants.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
3. First (I believe) aerodynamically unstable man rated launcher
Dunno about that one... The Gemini program's launch vehicles tended to suffer what was called the "Pogo" effect once they reached a certain speed and altitude. Tended to scare the shit out of the first astronauts to experience it.
The Apollo program had solved that.
Quo usque tandem abutere, Nimbus, patientia nostra?
There's a much more informative article on Space.com from yesterday: http://www.space.com/news/080819-nasa-ares1-vibration-update.html
3. Basically all space rockets are aerodynamically unstable. This is absolutely nothing new.
4. Before it was eclipsed by an even worse event, Apollo 13 briefly scared the crap out of everyone involved when the center engine of the second stage nearly ripped the entire rocket to little pieces. It was experiencing pogo oscillation, flexing the massive thrust frame by three inches at 16Hz, experiencing 68 gees. Just before this incredible vibration destroyed the entire craft, a fuel sensor was falsely tripped and shut the engine down, saving the ship.
Saturn V and Apollo were full of problems. Rocket science is hard, remember? I suggest that you get a clue before you mindlessly criticize.
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That is exactly what I have been saying. Apollo was the heaviest lifter we had, it worked, and it worked great. What's wrong with pulling out the blue prints, updating some components and building a newer improved version of the Apollo system? Why is this so hard to figure out? It's certainly better than wasting 1600+++ pounds on shock absorbers, damn that is just plane stupid. It's not like this is rocket..oh wait...but still!
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
>big, clunky, and with no regard for elegance.
Dealing with a vibration problem by adding nearly a ton of lead bouncy weights is not a great solution; especially when your mission is climbing out of a deep gravity well. They need to be looking for and fixing the source of the vibration.
Fortunately, they are. From Wired: "In the long term, Gary Lyles, associate director for technical management at NASA's Marshall Space Flight Center, said they are planning cold flow testing to learn more about the source of the vibration within the motor design itself. The next step would be sub-scale hot flow tests with solid rocket motors. If the tests prove conclusive, NASA will be able to look at doing a block upgrade to the motor and adding design changes to the full scale motor that will result in less vibration being produced. This would solve the problem without adding on extra weight to compensate for the problem."
Some mornings it's hardly worth chewing through the restraints to get out of bed.
Hilariously the apollo program had some pretty serious pogo oscillation problems. Pogo is shaking the rocket up and down makes the propellant flow increase and decrease making the oscillations worse.
In the apollo era, as per http://www.clavius.org/techsvpogo.html they used plumbing style water hammer chambers to eliminate the fluid surges. Let the vehicle shake but prevent the ability for shaking to cause thrust variations.
The modern solution is apparently dynamic shock absorber technology on the vehicle.
The modern solution eliminates the shaking, the old solution allowed it to shake but patched around it so it didn't have negative effects.
The modern solution is better, which makes the comparisons to Apollo kind of funny to those who know...
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger