Blue Origins capsule for New Shepard.

GW Johnson · 2017-04-04 12:50:13

Bob:

You cannot scale the length from the burn time. That implies an end-burner.

From the illustration, the motor case is approximately 20 inches diameter and at most 40 inches long without the nozzle. Minimum about 30 inches, when you allow for a curved pressure-vessel head in there somewhere.

If it were an end burner, 30 inches burnt in 2 sec is an average burn rate at average motor pressure of 15 in/sec. There is no such solid propellant. There never has been, not of any type of solid. There have been precious few that reached ~1 in/sec. Most are under 0.2 in/sec. Some are down near 0.05 in/sec. Cannot be an end-burner.

Half an inch/sec is a realistic "high burn rate" at average motor pressure. In a 2 sec burn time, that burns through a 1 inch web of propellant. The radius of the motor as illustrated is about 10 inches. If only half that were propellant web to burn, that's 5 inches, requiring an impossible 2.5 in/sec burn rate. So it's not a simple radial burner either, not at those proportions overall.

I took a very crude look at a wagon-wheel design inside a 20 inch diameter. That would be a 1 inch thick "rim" of propellant around the case to burn radially outward, with "spokes" 2 inches wide projecting inward from that rim toward the center. 6 of the spokes were 6 inches long, nearly reaching the center, and 6 were short at 3 inches long. They're 2 inches wide because each face burns toward the other. I don't really know all 12 spokes will fit without interference. Much less how the cast tooling could be made.

I got a web fraction (web/radius) 0.1 (as you would expect), cross sectional loading 44%, and overall volumetric loading of 41%, allowing some gas collection volume at one or maybe each end. 70,000 lb for 2 sec is 140,000 in-lb total impulse; at Isp = 249 sec for a high-solids, fine-AP propellant, with HTPB binder and 20% aluminum, that 562 lbm of propellant. The wagon-wheel grain that holds it is 64 inches long, which does not match the illustration. So it's not a wagon-wheel or similar design.

I have to conclude they have a custom grain design in there, one with only an inch or so of web to burn, but very much higher cross sectional loading than a conventional wagon-wheel or "finned" design. We had a custom one like that in Phoenix, but at over twice the L/D illustrated here, and a much larger web fraction. It would not serve here.

By the way, "web" is the distance into the propellant that you burn. It is always and everywhere perpendicular to the local burning surface. web = rate x time. Web x average surface = propellant volume.

GW

Last edited by GW Johnson (2017-04-04 12:59:28)

RGClark · 2017-04-04 14:02:59

Perhaps these images can give a better idea of the size of the motor:

index.php?action=dlattach;topic=10685.0;attach=477875;image

It's likely also there is a safety covering over the motor of some appreciable thickness. So the actual diameter would be less than what appears in the images.

Bob Clark

GW Johnson · 2017-04-04 19:13:43

That's why I picked 20 inches diameter, not 3 feet.

GW

SpaceNut · 2017-04-05 17:05:10

The capsule is designed for quick turn as the motor is a drop and replace designed, just check or adding new insulation inside the can which extends inside the capsule area.
I agree that a truck would not only change the center of balance but with it that complete section could become the new drop and replace for reflight. Then reload when your timeline indicates for the next schedueled flight.
I could see the initial price drop with full ocupency for all seats and a very rapid launch cycle....

GW Johnson · 2017-04-06 09:10:18

The second illustration in post 27 above is a cross section. It seems to show more-or-less what I concluded in post 26 above: a motor with considerable internal void space and a highly-configured burning surface to reduce the web to be burned.

It does appear larger than I first assumed, seemingly nearer 30 inches diameter instead of 20 inches diameter. Head-to-head, the pressure vessel is about L/D 1.5, with the grain assembly less than that. There's no clue what the objects nestled around the nozzle are.

Needs to be a design with a well-characterized reliability in test firings. Otherwise, a motor explosion would kill the crew before the crash could.

GW

tahanson43206 · 2021-06-07 05:40:06

BusinessFinancial Times
Jeff Bezos to go to space after stepping down at Amazon

Mr. Bezos is (apparently) planning to fly on his own vehicle.

If he succeeds (and survives) I would think that would be a winning round in his competition with Musk.

(th)

Mars_B4_Moon · 2021-06-09 06:40:54

More Faked Hype from Blue??

Yet another suborbital capsule?

Certain guys of the Private Sector have been hyped since way back in maybe 2002, 2003, 2004 from the very early days of this forum http://newmars.com/forums/viewtopic.php?id=1795 We were told how all the Millionaires the world and US Billionaire Private Sector Rockets were going to the Moon and Mars. The only person who has delivered after 20 years of hype about Millionaires and Billionaires owning the Moon is Musk.

I don't believe the Bezos hype, he owns media like the Washington Compost that spread 'news' to hype himself. I'm not going to call him a sophistacted 'fraudster' yet but he's 20 years doing it, trying to get up there and still sub-orbital but he's good at using lawyers & attorney to sabotage other members of the Private Sector... and for a multi millionaire, billionaire he's very good at claming welfare benefit from the US Government...now he wants what another 10 Billion from US Tax payers? At his rate of rocketry, The Planetary Society, Firefly space, Rocket Lab, Richard Branson, Brazil, South Korea Aerospace, the country of New Zealand, the Communist nations of Vietnam and even the 'Sea Launch' might rise from the dead zombie like from a bombed out civil war area of Ukraine and may get to Space Before Jeff Bezos.

Bezos is good at copyrighting stuff he never made and exploitation of loopholes in regulation in order to gain advantage or present figures in a misleadingly favorable light. Let's look at launch rates, when something goes horribly wrong with the launch in another nation or another Private company, Rocket Lab for example seems to be able to get back to launching faster than Blue Origin does when everything goes right The fact that 'Jeff Bezos' and his brother, Mark Bezos? claim to be going up on the next one just shows they must be getting desperate for publicity and even if sucessful he will still be ...Sub Orbital !!!
Maybe the Divorce and all those Union Worker lawsuits have finally driven the guy insane.
The guy wants a $10 Billion Bailout Fund for Bezos Space Firm that can not get a payload to Mars, nothing to the planet Venus, he does not even go to the Moon or the ISS but he still wants the sub orbital rocket funded?
Even if SpaceX were to hit get blasted by an asteroid or scifi space aliens in the morning he has already proven Bezos philosophy is the wrong method, Elon Musk inspires building and leadership, Musk's unique ability to juggle all these sciences, to tackle a whole bunch of insanely hard companies simultaneously may be fairly unique, he's becoming the JFK, Wright Borthers and VonBraun and Howard Hughes even if the government refuses to fully support him and finds itself corrupted and bribed by Bezos what will happen is guys and companies like SpaceX and Musk will continue to lead.

More Private Sector companies are coming from Canada from Spain from other places, they possibly have better engineers and a better work rate.
Another company coming Relativity Space will do launches
https://spacenews.com/relativity-raises … -r-rocket/
Relativity raises $650 million round, announces Terran R rocket

What if 'Virgin' beats him?

"Virgin Galactic is working on a plan to send Branson on a suborbital flight aboard the VSS Unity SpaceShipTwo rocket plane over the July 4 holiday weekend."

http://www.parabolicarc.com/2021/06/07/ … eff-bezos/
This would beat Bezos by a couple of weeks.

Last edited by Mars_B4_Moon (2021-06-09 07:14:24)

SpaceNut · 2021-09-24 19:36:12

William Shatner is headed to space next month aboard Bezos rocket

The 90-year-old will take part in a 15-minute civilian flight in October, and the whole thing will be filmed for a documentary.
The "Star Trek" alum will reportedly head to space next month aboard the New Shepard capsule rocket

GW Johnson · 2021-09-25 12:49:30

Look, the more people fly aboard Bezos's rocket/capsule or Branson's rocket plane, the better. Same for Musk's rocket/capsule into orbit. So what if they are rich? It's more folks that are NOT government employees, and more publicity, than we ever had before.

Might not be as good as it could be, but it sure beats the ever-lovin' hell out of what we had before. You have to maintain some perspective about this.

GW

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#26 2017-04-04 12:50:13

Re: Blue Origins capsule for New Shepard.

#27 2017-04-04 14:02:59

Re: Blue Origins capsule for New Shepard.

#28 2017-04-04 19:13:43

Re: Blue Origins capsule for New Shepard.

#29 2017-04-05 17:05:10

Re: Blue Origins capsule for New Shepard.

#30 2017-04-06 09:10:18

Re: Blue Origins capsule for New Shepard.

#31 2021-06-07 05:40:06

Re: Blue Origins capsule for New Shepard.

#32 2021-06-09 06:40:54

Re: Blue Origins capsule for New Shepard.

#33 2021-09-24 19:36:12

Re: Blue Origins capsule for New Shepard.

#34 2021-09-25 12:49:30

Re: Blue Origins capsule for New Shepard.

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