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#176 2019-04-04 17:45:18

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

That was turned over to the military when shuttle budgets were gutted and the new direction for going forward was announced. We do have a topic on it as well.
The big thing for it is staying power on orbit for years...

http://newmars.com/forums/viewtopic.php?id=3219

http://newmars.com/forums/viewtopic.php?id=3809

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#177 2019-05-28 19:59:48

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

Try, try, try again and again until you get it right....NASA says SpaceX readying crew ship for possible flight by end of year

052819-demo2.jpg

Nasa is not happy with the communications of the details for what happened and that will have an impact for the future if they are not satisfied as to what they are told.

The first flight of the CST-100 Starliner, a capsule that will launch from the Cape Canaveral Air Force Station atop a United Launch Alliance Atlas 5 rocket is planned for late this year.

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#178 2019-06-05 19:44:29

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

NASA shrugged off a spate of design and test mishaps, saying such setbacks were “part of the process”.. simply meaning they will take the risk even if they could die....

NASA's first SpaceX astronauts ready for 'messy camping

This should not have taken more than a decade to get a manned flight on an American rocket....

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#179 2019-08-25 18:26:54

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

seems there is a terminal case of delay going on
http://www.spacedaily.com/reports/Test_ … n_999.html

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#180 2019-10-13 19:16:35

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

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#181 2019-10-13 21:19:40

Oldfart1939
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Registered: 2016-11-26
Posts: 1,757

Re: COTS - status

...subject to delays...

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#182 2019-10-20 16:59:11

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

What makes off the shelf is the ability for any one that can afford to purchase the same ability to use the parts. Firefly Aerospace partners with Aerojet Rocketdyne 3D printing of Firefly's Reaper engines, according to the formal announcement.

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#183 2019-10-22 08:31:12

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,696
Website

Re: COTS - status

Sure looks to me like NASA is rigging the COTS game to make sure Boeing flies first.  Until the Crew Dragon blew up,  it didn't look like they could credibly do that,  but it happened,  and they are using it. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#184 2019-10-22 12:33:10

Oldfart1939
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Registered: 2016-11-26
Posts: 1,757

Re: COTS - status

This is simply an unmanned capsule to ISS, and recapitulates what SpaceX did over 6 months ago. In the interim period, SpaceX will launch the inflight abort test. Parachute testing continues for certification of the Dragon recovery system.

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#185 2019-10-22 18:35:24

louis
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From: UK
Registered: 2008-03-24
Posts: 5,079

Re: COTS - status

Yep - I am sure you are right - hence the infamous tweet....

GW Johnson wrote:

Sure looks to me like NASA is rigging the COTS game to make sure Boeing flies first.  Until the Crew Dragon blew up,  it didn't look like they could credibly do that,  but it happened,  and they are using it. 

GW


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#186 2019-10-23 03:30:11

elderflower
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Registered: 2016-06-19
Posts: 1,140

Re: COTS - status

Given the shenanigans currently being exposed in Boeing by the 737max certification issue, they will be desperate for any distraction.

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#187 2019-10-23 17:25:15

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

A good reason not to award anything more to them until they can clean up there act.
Blue Origin's moon deal with Lockheed, other firms, signals new era

The Altiar design was to heavy so hopefully theirs will not be.

I would not call the Blue Origin's moon deal with Lockheed, other firms, signals new era but to call the NASA's 2nd attempt an aggressive plan to return people to the moon by 2024, and to establish a moon base since announcing the path back in 2010. The shuttle program ended in 2011, NASA began moving toward a more commercialized model thanks to a game change early on the congress workfare program.

Blue Origin said it will build the descent module -- it's Blue Moon lander -- that will be stacked with other modules. It also will lead program management along with systems and mission engineering.Northrop will build a transfer module that will guide the Blue Moon from NASA's planned lunar gateway that will orbit the moon.

Lockheed will build a reusable ascent module that will launch back into space from the lunar surface. Lockheed also will lead crewed flight operations and training.

The descent stage should be easily achievable for them....

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#188 2019-10-24 19:36:28

Oldfart1939
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Registered: 2016-11-26
Posts: 1,757

Re: COTS - status

The Blue Origin, Northrop Grumman, Lockheed Martin group will need to get a realistic design put together quickly. My only concern is what will be the end result, as we all remember: "A camel is a horse designed by a committee."

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#189 2019-10-24 20:07:25

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

If the one that is footing the bill for the work they will get what they want in the design the question is whether the big shots will listen to the one that has the cash and has already proven that he can launch and return as well as develope engines.
Northrop Grumman, Lockheed Martin have the desired talent in there engineers the question is will they listen to the design concepts or keep heading down the gateway path....
Got lite, dig in and keep the flights coming....

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#190 2019-10-25 11:50:08

elderflower
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Registered: 2016-06-19
Posts: 1,140

Re: COTS - status

Oldfart is very rude to camels.

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#191 2019-10-25 17:21:50

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

Once when the fish is out of the water would a camel be wrong in a green pasture....but then again look at who is on the committee to see why it happened.

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#192 2019-10-26 08:56:57

Oldfart1939
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Registered: 2016-11-26
Posts: 1,757

Re: COTS - status

Elderflower-

Conan the Barbarian had good reason to dislike camels.

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#193 2019-10-26 10:23:39

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,696
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Re: COTS - status

I suppose there's camel's toes and camel toes.

Language is slippery,  is it not?

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#194 2019-11-03 21:22:33

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

SpaceX trumpets progress on commercial crew parachute testing it has now carried out 13 consecutive successful tests of a new parachute design for its Crew Dragon spacecraft after overcoming initial problems with it.

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#195 2019-11-04 19:23:56

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

The Boeing Starliner today did a test of the escape system from a ground launch platform and it went from 0 to 600 plus mph in 5 seconds. It landed a short time later after achieving 1 mile in distance carried by its parachutes to an earth landing on the air bags.

AAJOQJY.img?h=436&w=799&m=6&q=60&o=f&l=f

Boeing Tests Starliner Spacecraft's Launch Abort System for Rocket Emergencies
https://videos.space.com/m/Fo1GmKuy/see … t=9wzCTV4g

Starliner capsule was programmed to reach a speed of 650 mph (1,046 km/h) in just 5 seconds. Engines on board the spacecraft fired intermittently over the course of 10 seconds in order to carry the capsule away from the launch pad and the hypothetical unstable rocket.
Then, the spacecraft oriented itself and a suite of parachutes released in three pulses over the course of about 25 seconds. The parachutes are crucial for crew safety because they both slow the capsule down and orient the spacecraft for a safe landing.

Those parachutes come in three pulses: two drogue parachutes, three pilot parachutes and three main parachutes. Only two of the last category deployed during today's test, but that is within the range of acceptable safety conditions for the vehicle, Landa said.

About 60 seconds into the procedure, the Starliner capsule jettisoned its heat shield and deployed airbags to soften the landing still further.

Boeing's next launch for the Starliner vehicle, its uncrewed demonstration mission to the International Space Station, is scheduled for Dec. 17 from Florida.

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#196 2019-11-04 21:22:10

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

Speaking of parachutes for mars they are getting next to not being something that is useable to slow a payload to mars as the mass continues to climb.

https://ntrs.nasa.gov/archive/nasa/casi … 005898.pdf

The equation is derived which expresses the tension in the partially unfurled parachute in terms of the physical characteristics of the system and of the deployment rate which can be determined by a numerical solution of the fundamental equations of motion.

https://ntrs.nasa.gov/archive/nasa/casi … 005172.pdf

We can apply an equation from the Rocket Equations Page to figure out the parachute needed for your rocket and how fast your rocket will be going during descent. The rocket, under its parachute, will speed up toward the ground until the drag force on the chute is equal to the weight of the rocket.

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#197 2019-11-08 11:56:10

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,696
Website

Re: COTS - status

According to AIAA's "Daily Launch" email newsletter (and some other stories from other sources),  the failed parachute during the Dreamliner abort test was a parachute rigging error.  Literally,  it was not connecting the extraction drogue to the main chute it was supposed to extract. 

This is from the same Boeing that screwed up a stability augmentation system on 737MAX,  and screwed up a fatigue life design on the wing attach forks in the 737NG. All I have to say is this so very clearly ain't the same Boeing that built the B-17 and the B-52.

And by the way,  the reason the lunar landers NASA is seeking are as big as they are,  is the 3000 km x 70,000 km orbit of LOP-G about the moon.  This drives up the one-way delta vee from about 1.6 km/s for low circular lunar orbit to something near full lunar escape speed (about 2.38 km/s). 

They (NASA) did this weird damned orbit for LOP-G so that SLS block 1 with Orion could actually reach it,  or with useful payload without Orion.  But getting from the LOP-G to the lunar surface is much harder than it was from low circular lunar orbit for Apollo. 

This whole farce is to justify SLS with something it can actually do.  And I still don't see any solar flare radiation protection in the LOP-G crew module designs.  They will kill a crew if they ever do get this thing into that ridiculous orbit about the moon. 

Stupid is as stupid does.

GW

PS -- I have seen Spacex define roughly what went wrong with Crew Dragon.  The explosion traces to a leaking check valve in an NTO line feeding the Super Draco system.  The NTO reacted with the metals in the helium pressurization system,  causing the explosion.  No real details,  though.  Supposedly,  they are replacing the check valve with something else,  presumably some sort of positive cutoff.  Not so sure why two check valves in series would not work just as reliably,  but that's just me.  Meanwhile,  they seem to be doing better than Boeing at remembering how to rig parachutes.  That technology is well over half a century old. Closer to a full century for low speed chutes.

Last edited by GW Johnson (2019-11-08 12:03:23)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#198 2019-11-09 09:42:22

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,810
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Re: COTS - status

My concern is the brown cloud. The idea of using the service module for launch abort is brilliant! Why waste mass on two systems when one system will do? It's more efficient. But this video shows the service module crash; when it hit the ground a brown cloud formed. That's N2O4 aka NTO released when the tanks ruptured due to crashing. That stuff is toxic.

For the Apollo-Soyuz mission in 1975, when the Apollo capsule returned, crew failed to flick the switch disabling/securing the automated system that uses thrusters to maintain capsule orientation. After main parachutes deployed, the automation system tried to use thrusters to fight against capsule rocking and sway as it was suspended under the chutes. When the capsule entered thick atmosphere, a valve opened allowing fresh air to enter the capsule, to equalize pressure. Remember, in space Apollo used 100% oxygen at 5 psi. But when thrusters fired at the same time this valve was open, it allowed N2O4 from the thrusters to enter the capsule. This caused the capsule to fill with visible vapour, and all astronauts suffered from inhalation.

Wind will tend to catch the parachutes, pushing the capsule farther down wind. That means when the service module crashes, there's danger of wind blowing N2O4 toward the capsule. How far did the SM crash from the capsule? Is this safe?

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#199 2019-11-09 10:32:38

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 16,492

Re: COTS - status

That would mean we need an added layer of materials for the tanks to be able to survive a crash or hard landing in that you change the design for the worst and live rather than die for under protection.

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#200 2019-11-09 10:58:27

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 3,696
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Re: COTS - status

I have grave doubts about ever armoring tanks enough to survive a crash.  That would be very heavy indeed.  Way too heavy to fly.

A better solution is to vent the NTO tanks immediately after service module separation,  while the service module is still falling,  so that those tanks are empty when it crashes.  The hydrazine is toxic enough (rather resembling anhydrous ammonia),  but the NTO is far worse as a toxin.

A possible best solution would be to rig some means of self-destruct for the service module just after separation.  That might be as simple as simultaneously venting both the NTO tanks and the hydrazine tanks,  since they are hypergolic.  But I have concerns over how reliable the complete self destruction might be,  if done that way.

The other route to protect the crew from vapors released by the crashed service module would be some sort of emergency breathing gear.  A full face mask or helmet is needed,  a simple oxygen mask will not serve,  not with NTO.  I presume they return in pressure suits.  The easiest thing to do would be to close the helmet visors (and reseal the gloves!) and go back on oxygen,  until they can walk clear.  That requires a portable oxygen bottle for each person.

GW

Last edited by GW Johnson (2019-11-09 11:01:32)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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