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Drop test of Boeing’s Starliner capsule

The competition heats up: Boeing has successfully dropped a fullscale test vehicle of its Starliner manned capsule into water.

Video below the fold. It isn’t very spectacular, as all they do is lift the capsule up about 35-40 feet and then drop it at an angle into a tank of water. Nonetheless, it shows that construction is moving forward briskly.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 
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"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

17 comments

  • pzatchok

    That some now did not look right.

    The bags were collapsed but I do not know if they are needed for flotation or just impact cushions.

  • Dick Eagleson

    I think they’re supposed to deflate after impact. Leaving them inflated would raise the center of mass above the water line and leave the capsule more vulnerable to being upended by wave action than if it rides low in the water. Apollo had flotation bags to prevent such a mishap as well – or at least to right the capsule quickly if waves did flip it over – but those bags were near the top of the capsule, not on the bottom like the energy-absorber bags on Starliner.

  • PeterF

    It looked to me like the bags deflated upon impact but retained some inflation for buoyancy. NASA learned the hard way when Gus Grissom’s capsule sank. This is why this non-exciting test was accomplished in a pool. I hope they repeat it in a wave pool and at different angles of entry and speeds. They need to find the limits. – Wonder if it would fit on top of the Falcon 9…. or the Blue origins booster…

  • Jwing

    Didn’t we do similair tests about 50 years ago with the Apollo capsule?! My word,…..I never thought that in 2016 I’d be watching an exact copy of the command module being water tested as an example of this country’s latest progress in space.

  • Steve Earle

    I’m sure capsules have their place in a well-rounded spacefleet. But you’re right, seeing a disposable 1960’s like capsule isn’t what I would have expected in the here and now, even if it is bigger and better.

    And a well-rounded spacefleet is not what we have, at least not yet. After the shuttle first flew I assumed we would eventually complete the transition to space-planes and have cheap-reusable flights to low orbit at every major air-field. Maybe with a nice linear accelerator next to each runway.

    Guess I was reading too many Popular Mechanics cover stories back then :-)

  • PeterF

    The best place to put a linear accelerator would be on the west face of a mountain in Ecuador. The Panama canal was built with steam shovels and dynamite. The Ecuadorian government might actually welcome the economic boost. I wonder what the cost for that construction would be compared to the SLS?…

  • pzatchok

    Since a linear accelerator will never be able to push a ship all the way to space I wonder just how high and fast a rocket could be launched could be launched with one.

    Does anyone know the atmospheric resistance limit?

  • Steve Earle

    Good idea about Ecuador, I vote for two more as well in Borneo and somewhere in mid-Africa. Eventually the tech would get better and be able to move away from the mountains and the equator.

    So why don’t we have them? Why are we still using brute-force rockets pointing straight up towards the sky?

  • Edward

    The test is more of a proof of hardware than a proof of concept. The inflated bags likely are needed to cushion the blow because of the added weight of the capsule, and it looks like the outer ring of bags are also used for flotation. Scaling up can be harder than we think, so it is good to verify that the change in weight to surface area does not result in disaster.

    As for a linear accelerator/mass driver, this may be more useful for bulk material than it is for spacecraft, especially large spacecraft, as the accelerations are horrendous. Keeping a 10,000 lb., 700 cubic ft. satellite intact for a 3g launch is hard enough. However, it would be interesting to see if cubesats could be strong enough to be launched by a mass driver.

  • Steve Earle

    But, but,…. Popular Mechanics! They couldn’t have been wrong, could they?

    My guess is you’re right, cargo craft and durable goods only. Have there been any efforts in that direction? Or is it still at the level of the Rail Gun just now getting a tryout w/ the Navy after years of talk?

    Speaking of Mass Drivers, I just watched an old Babylon 5 episode where Mass Drivers were used to destroy cities from orbit.

    I hope for our sake we don’t ever see that in real life.

  • Edward

    Steve wrote: “I hope for our sake we don’t ever see that in real life.”

    As I recall, Londo Mollari was horrified by the sight, too.

    As I think about it, the reason our satellites are lightweight and fragile is because of the limitations of the rockets that take them up. If mass drivers were used, satellites might be able to be made heavier and stronger in order to survive the forces of acceleration. That is something else that would be interesting to investigate. Vibrations and acoustics related to the mass driver would also have to be taken into account. The shrouds that protect satellites from the airstream tend to vibrate and act as huge speakers, blasting loud acoustical noises at the enclosed satellite, and I suspect the same problem would exist for payloads launched by mass drivers.

  • pzatchok

    A linear accelerator could be made long enough that the acceleration is kept to a reasonable limit. around 3g’s constant is fine.
    Dragsters do 4+
    Patriot missiles turn at over 10.
    fighter jets pull over 8 in turns.
    Hell a human pulls over 3 during a sneeze.

    The problem is the max sustainable speed.
    The air is to dense even at the highest mountain to launch just a payload. We would have to launch a rocket for assistance to reach orbit.
    The hyper-sonic speeds needed would burn up any payload before it reached orbit.

    I could see it as a replacement for the first stage rocket. Nothing more.

  • PeterF

    A linear accelerator as a first stage replacement has been speculated for years instead of using an aircraft to carry a vehicle to a higher launch altitude. (remember the X-15?) (All the pilots qualified for astronaut wings)
    A maglev sled accelerator at the equator would gain the 900mph rotation speed of the earth as well as the speed of the fully reusable electrically powered sled/glider. Solid rocket boosters would be strapped on the sled for added thrust as needed.
    Hypersonic speeds can be achieved using a helium atmosphere along the accelerator terminus section as it is at the Holloman test track. (A MUST see if you ever get the chance.) Instead of a plastic baggie a more permanent structure would conserve the helium.

    On the moon a similar facility could consist of an oval “race track”. The solar powered sled would return to start after imparting escape velocity or even earth return velocity to payloads with no need for atmosphere shrouds.

  • Edward

    Pzatchok wrote: “A linear accelerator could be made long enough that the acceleration is kept to a reasonable limit.”

    Please keep in mind how far a rocket travels as it accelerates at around 3g, even just the first stage. To really make this work, a higher acceleration would be necessary so that the accelerator could be a more reasonable 2 or 3 miles long.

  • Steve Earle

    I’m starting to see why we have never built one. Sounds like it’s still easier and cheaper to build First Stages than to build an accelerator that still requires the Second/Third stages to achieve orbit.

    Clearly they would be best suited for the Moon or Mars where air density wouldn’t be an issue.

    And Edward, you are correct, Londo Mollari was horrified, but not horrified enough to do anything differently. Good illustration of how power corrupts and leads to bad bad things…..

  • pzatchok

    The Helium shroud idea is fine for very short tracks but is not for a space bound linear accelerator.

    If you permanently enclose it you still have to deal with the sonic booms. They just happen at a higher speed.
    And you still have to deal with the impact of hitting the normal dense atmosphere when you leave the helium tube.

    As for length a linear accelerator for the speeds we would be needing as not much more than a really good maglev train. And we already make those things pretty long. As in hundreds of miles.

  • Edward

    Careful about the hundreds of miles accelerator. It limits the places that you can build, especially if you want to end the accelerator at high altitude.

    I can imagine a 10-mile accelerator that curves up a mountain at the end, but the g-forces to curve the payload upward may be killer.

    One option could be one of the sharpest drops (climbs) on Earth, Telescope Peak at 11,000 feet with a base, eight-ish miles away, at about 1,000 feet in Death Valley (Panamint Valley). That would make for a 20-ish degree, eight-ish mile accelerator.

    https://en.wikipedia.org/wiki/Telescope_Peak#Geography

    Someone should check my math, but I came up with a 20g acceleration on a 10 mile accelerator to get to 1.5 miles/per second, which is close to the speed at which a first stage might burn out (although, it would probably happen closer to the von Karman line than 11,000 feet altitude).

    So now, in order to make this work, we need second stages and payloads that can handle 20g accelerations. This is not impossible, as anti-aircraft missiles have higher accelerations, sometimes reaching mach 1 shortly after leaving the launcher, and sometimes have second stages. However, the size or type of payload that can be launched this way may be limited.

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