Ares I DM-2 Motor Test - Aug 31, 2010

[rdale]

ATK confirms that the DM-2 test is still funded and will take place in the fall. I can't seem to find if there are major differences between last fall's DM-1 and this one though other than a change in the exit cone design.

[phred]

I would think there would have to be major differences, or else why would there be another test?

[rdale]

A different end/exit cone design, but I'm not sure what all that involves.

[FinalFrontier]

ATK confirms that the DM-2 test is still funded and will take place in the fall. I can't seem to find if there are major differences between last fall's DM-1 and this one though other than a change in the exit cone design.

There is no way this will happen unless there are things going on behind closed doors that we are not aware of, or unless there is more to this "garver gambit plant" then previously thought. Otherwise there is no reason for a four or five segment booster anymore for anything only Jupiter or ares could use them and they are both dead right now.

[rdale]

From what I understood - it's already paid for (other than test labor) so there wasn't much to be gained by selling it for scrap.

[phred]

It would seem a shame to dispense with such a major componant as this family of motors.  The 2011 budget summary does call for "New approaches to first stage launch propulsion."  Maybe that means a more sophisticated liquid propellant booster (with flyback capability?)

It's speculation at this point.

phred

[Patchouli]

How far along is the 5 segment RSRM and could it be applied to a new SDLV?

[robertross]

How far along is the 5 segment RSRM and could it be applied to a new SDLV?

Probably a year away at the most?
One of the interesting comments I made a while back on the Direct thread (though it was taken out of context) was that 'IF' they were spending more time trying to adapt the propellant burn characteristics to ensure reduced thrust oscillation, and Ares I isn't needing it any longer, then a Jupiter (or any inline SDHLV) could use it as-is due to the attachement method in the ET, and how it dampens this out.

Of course they still need more things tested on this SRB, like parachutes, so it still has way to go, but if we 'drop' the need for reusability in the near term (as in get a pair of unqualified flight units), then we should be able to mount the 4-segment recovery system on top and see how that works. If it doesn't, then it really doesn't matter.

Course this will probably never happen...

[wannamoonbase]

Another example of a broken Washington government.  A useless system continuing nearly a year after a very obviously dead vehicle.

The feds need to start writing better contracts.

[sandrot]

[...] The feds need to start writing better contracts.

They did a good job apparently. Isn't it illegal to change the course (despite Obama's wishful thinking?).

[HIPAR]

Sometimes it costs less to allow a contract to complete a milestone rather than pay termination costs.  With all that talk about NASA eventually perusing heavy lift to go beyond LEO, these motors may retain some purpose.

---  CHAS

[Jorge]

Another example of a broken Washington government.  A useless system continuing nearly a year after a very obviously dead vehicle.

The feds need to start writing better contracts.

The feds cannot write contracts that violate federal law, namely the Congressional Budget and Impoundment Control Act of 1974.

Funds appropriated by Congress (in this case, CxP funding for FY10) cannot be impounded by the executive branch (in this case, NASA) for other purposes unless Congress passes supplemental appropriations language allowing it.

The fact that the executive branch has a budget proposal for FY11 that cancels the program in question has no bearing on the law.

[JohnFornaro]

Another example of a broken Washington government.  A useless system continuing nearly a year after a very obviously dead vehicle.

The feds need to start writing better contracts.

The feds cannot write contracts that violate federal law, namely the Congressional Budget and Impoundment Control Act of 1974.

"Writing better contracts" cannot be considered as a suggestion that the feds should be writing contracts that violate the law, so the admonition seems unnecessary.

[rdale]

ATK:

The test bay @ ATK is being readied to stack segments for the 2nd full scale test fire of Ares I 5-segment solid rocket motor this fall.

[renclod]

The 3rd segment of the Ares I first stage DM2 is in the test stand at ATK in prep for ground test early Sept, 2 more segments to go

[renclod]

http://www.nasa.gov/images/content/450887main_179554-07.jpg
http://www.nasa.gov/images/content/450891main_179554-14.jpg

"The 4th segment of Ares I first stage is in the test stand in prep for ground test early fall - one more segment to go"

[sdsds]

Of course ATK might proceed with the test regardless of funding, but September 30 is the end of FY10.  Are they on track to fire this motor before then?

[renclod]

Of course ATK might proceed with the test regardless of funding, but September 30 is the end of FY10.  Are they on track to fire this motor before then?

September 2 (according to @ATKRocketNews)

[Will]

Of course ATK might proceed with the test regardless of funding, but September 30 is the end of FY10.  Are they on track to fire this motor before then?

If the contract is cancelled, firing the motor is probably the cheapest way to dispose of the propellant.

[renclod]

ATK: NASA releases funds: Ares rocket work may continue through at least September

http://bit.ly/dcdAy0

>>> "We have received our routine contract notice from NASA for incremental funding through the remainder of GFY10," said Trina Patterson, senior manager of media relations for ATK Space Systems.
...
The 2010 funding of $160 million allows for another Utah test of the rocket motor in September as part of the completion process for the first stage of the Ares I. <<<

[rdale]

DM-2 scheduled for Sept 2, 2010

http://www.nasa.gov/pdf/466575main_07022010_wkly_summary.pdf

[jacqmans]

News Release Issued: July 7, 2010 9:00 AM EDT

ATK Completes Installation of World's Largest Solid Rocket Motor for Ground Test
NASA's First Stage Test is Currently Scheduled for Early September
PROMONTORY, Utah, July 7 /PRNewswire-FirstCall/ -- Engineers and technicians at Alliant Techsystems (NYSE: ATK) and NASA have completed installation work on the second Ares I First Stage five-segment Development Motor (DM-2), in preparation for its static-fire, which is currently scheduled for early September.

(Photo:  http://photos.prnewswire.com/prnh/20100707/CG31370)

(Photo:  http://www.newscom.com/cgi-bin/prnh/20100707/CG31370)

The Ares I First Stage is the largest solid rocket motor ever built.  It was designed to maximize astronaut safety while providing the nation with a reliable launch capability for both crew and cargo missions.  As the prime contractor, ATK continues to perform on schedule and cost in support of NASA's space exploration programs.

The motor, which is 154 feet in length and 12 feet in diameter, has been installed horizontally in a specialized test stand in Utah.  Results from this test will be compared with data from the ground test of the first five-segment motor and Ares I-X test flight both successfully completed last year.

"A robust ground and flight test program is a critical part of human-rating to ensure reliability and safety when launching crew into any orbit," said Charlie Precourt, VP and GM of ATK Space Launch Systems. "This test is a vital milestone in further growing the performance database for this new five-segment solid rocket motor."

Although the five-segment motor is based on the design heritage of the flight-proven Solid Rocket Boosters on the Space Shuttle Program, it was upgraded utilizing modern technologies and materials.  These include the addition of a fifth segment, changes to the propellant grain, a larger nozzle opening and upgraded insulation and liner.

"We designed this motor using a knowledge base gained from over three decades of operations, during which we constantly monitored and improved our design," said Precourt.

ATK technicians are in the process of instrumenting the five-segment rocket with sensors and gages to collect measurements on more than 750 data channels. This information will be used to evaluate performance, roll control, acoustics, motor vibrations, oscillations, nozzle modifications and insulation upgrades. The full-scale motor test will advance the safety, technology and knowledge of solid rocket motors.

When fired, the motor will produce 3.6 million pounds of maximum thrust or 22 million horsepower.  Utilizing the in-line configuration with a single five-segment solid rocket motor first stage and liquid upper stage, this launch vehicle is designed to lift more than 54,000 pounds of payload directly to Low Earth Orbit.

"The combination of a solid propulsion first stage and liquid propulsion upper stage provides optimum payload capability, reliability and lowest cost," said Precourt. "These motors were designed not only to carry humans to orbit but also for use on a heavy lift vehicle where performance and reliability are key requirements."

The DM-2 ground test will:

Validate numerous design improvements to the insulation, liner, propellant and nozzle systems.
Provide side load data that can be used in future test flights leading to heavy lift development.
Compare roll torque data to information collected from the stable flight of Ares I-X to further the design of the roll control system.


The first stage is designed to be recovered and reused. This enables NASA and ATK to collect vital post-flight information and performance data, confirming a safe and robust design.

ATK is a premier aerospace and defense company with more than 18,000 employees in 24 states, Puerto Rico and internationally, and revenues of approximately $4.8 billion.  News and information can be found on the Internet at www.atk.com.

[edkyle99]

... also, the small issue of shaking the crew

That problem was addressed.

Two higher-res. images of what could end up being the prototype booster for Sen. Nelson's new rocket. 

 - Ed Kyle

[renclod]

Anyone care to take a stab at the pros & cons for a layperson like myself? Thanks.

I am sure many would care, but hopefully not here in this thread.
This is a DM-2 test dedicated thread.
Let's keep it on topic.

[phred]

So, the temperature of this motor will be lowered for the test.  I wonder how this is done.  It's a big motor.

Also, is the temperature lowered to test for the likelihood of a Challenger accident sort of problem?

phred

[Downix]

So, the temperature of this motor will be lowered for the test.  I wonder how this is done.  It's a big motor.

Also, is the temperature lowered to test for the likelihood of a Challenger accident sort of problem?

phred

Give me a few hundred gallons of LN2, I'll get the temperature down....

[renclod]

So, the temperature of this motor will be lowered for the test.  ... is the temperature lowered to test for the likelihood of a Challenger accident sort of problem?

The main goal is to characterize dispersions due to MBT variations.
MBT=mean bulk temperature (of the solid propellant)
When the solid propellant is warm, it burns faster, more energetic.
When cold, it burns less energetic, and longer.
In all, the total impulse generated is approx. the same.
But this dispersion influences the launch trajectory and must be accounted for.
The Shuttle does that too.
It is also quite important for the Orion's LAS (the tractor motor's characteristics, not the RSRMV).
And of course it is important for a single stick launcher's first stage, like Ares I. Also for a booster like Ares V.

[renclod]

http://www.nasa.gov/pdf/470054main_july162010_wkly_summary.pdf

"... specifically conditioned to 40 °F propellant mean bulk temperature.
Specific test objectives associated with the cold temperature include
demonstration of low temperature o-rings (no heaters),
internal insulation/field joint j-leg performance,
and overall ballistic performance of the RSRMV."

[rsnellenberger]

"demonstration of low temperature o-rings (no heaters)"

It's good to see that Roger Boisjoly's tests finally got scheduled...

[Calphor]

So, the temperature of this motor will be lowered for the test.  I wonder how this is done.  It's a big motor.

Also, is the temperature lowered to test for the likelihood of a Challenger accident sort of problem?

phred

There is actually a building that has been rolled (it is on a track) over the motor and the entire building has been cooled to the correct conditioning temperature. Once the motor has been properly conditioned, just before firing, the building will be rolled back exposing the motor for the test fire.

[Calphor]

"demonstration of low temperature o-rings (no heaters)"

It's good to see that Roger Boisjoly's tests finally got scheduled...

IIRC they actually changed the O-rings to a more resilient material with a lower glass transition temperature.

[rsnellenberger]

"demonstration of low temperature o-rings (no heaters)"

It's good to see that Roger Boisjoly's tests finally got scheduled...

IIRC they actually changed the O-rings to a more resilient material with a lower glass transition temperature.

Well, I assumed that there was some technical improvement to be tested -- but couldn't resist the snarking opportunity, considering the requests for o-ring testing support that preceded the Challenger accident.

[psloss]

"demonstration of low temperature o-rings (no heaters)"

It's good to see that Roger Boisjoly's tests finally got scheduled...

IIRC they actually changed the O-rings to a more resilient material with a lower glass transition temperature.

Well, I assumed that there was some technical improvement to be tested -- but couldn't resist the snarking opportunity, considering the requests for o-ring testing support that preceded the Challenger accident.

Of course it wasn't until after the accident, but a lot of testing was done as a part of the redesign effort.  There was a good deal of testing of both "original" joint designs (case/case and case/nozzle) in 86-87; there's footage of at least one JES test where the ignition behavior on 51-L was more or less reproduced on the joint between the two right-hand aft segments.

[rdale]

Per latest weekly update, launch moved up to Aug 31.

http://www.nasa.gov/pdf/471972main_july30_2009_wkly_summary.pdf

[ugordan]

Per latest weekly update, launch moved up to Aug 31.

Wishful thinking? 

[JayP]

Per latest weekly update, launch moved up to Aug 31.

Wishful thinking? 

Depends on your point of view. If it Launches, something went really, really wrong

[Space Pete]

The Huntsville Times: "ATK sets test this month for next Ares 1 solid rocket motor".
http://blog.al.com/space-news/2010/08/atk_sets_next_test_for_next-ge.html

The test will be a horizontal ground test firing Aug. 31 at 10:05 CDT at ATK's facility in Promontory, Utah.

[FinalFrontier]

Per latest weekly update, launch moved up to Aug 31.

Wishful thinking? 

Depends on your point of view. If it Launches, something went really, really wrong

LOL

Well 5 seg may have a "sunk cost" place on SLS. OFC we dont actually need 5 seg, but its sort of a "well now we have it." type thing. I suppose it would be nice to see these tests not go to waste

[Space Pete]

ATK and NASA to Perform Second Ground Test of the Ares Five-Segment Solid Rocket Motor.

Aug 11, 2010

PROMONTORY, Utah, Aug. 11 -- Alliant Techsystems (NYSE: ATK) and NASA will test the second fully developed Ares five-segment solid rocket motor, known as Development Motor-2 (DM-2). The five-segment rocket motor is an upgraded version of the Shuttle's 4-segment booster, and has also been identified as a key element of NASA's future Heavy Lift Launch vehicle.


What:

Horizontal ground test firing of Ares DM-2.


Date:

Tuesday August 31, 2010.


Time:

9:05 AM MDT.


Where:

ATK Aerospace Systems facility in Promontory, Utah


Test Objectives/Background:

• A total of 53 design objectives will be measured through more than
  760 instruments.
• DM-2 is a "cold motor" test. The motor will be cooled to 40 degrees F
  to measure solid rocket motor performance at low temperature, as well
  as to verify design requirements of new materials in the motor joints.
  These new materials will allow for the elimination of joint heaters that
  were necessary in the original 4-segment motor design. This will save
  significant weight, further reduce system complexity and simplify
  launch operations, while simultaneously delivering increased operating
  margins at lower ambient temperatures.
• Other objectives include data gathering on vital motor upgrades such
  as the new insulation and motor case liner and the redesigned nozzle
  which increase the robustness of the design.
• When fired, the motor will produce a maximum thrust 3.6 million
  pounds, or 22 million horsepower.
• The cases have all previously flown on the space shuttle, collectively
  launching on 57 missions.
• A public viewing area is available along State Road 83 North
  approximately 20 miles west of Corinne, Utah.


Media Contacts:

Trina Patterson

George Torres
   
Cell: 801-699-0943
   
Cell: 801-699-2637
   
email: [email protected]
   
email: [email protected]


http://atk.mediaroom.com/index.php?s=118&item=1025

[Space Pete]

Check out ATK's "trailer" for DM-2!

[JosephB]

Anyone know how long the cool down period lasts?

[gladiator1332]

Check out ATK's "trailer" for DM-2!

What cost more, the DM-2 test or that video? 

[e of pi]

What cost more, the DM-2 test or that video? 

Personally I just love the line, "Soon everyone will believe!" It's like a soon as this test happens we'll all wise up and see how critical a five-segment SRB is to everything and they'll show those fools who laughed at them at the academy.

...Perhaps I read too many webcomics about mad scientists.

[Hauerg]

So ATK is filming a glossy commercial for a static test firing.
No wonder that space has been that expensive all those years..

[e of pi]

So ATK is filming a glossy commercial for a static test firing.
No wonder that space has been that expensive all those years..

But without the commercial, how will they show them all?

[TheFallen]

So ATK is filming a glossy commercial for a static test firing.
No wonder that space has been that expensive all those years..

The question is: Does that Tom Cruise-wannabe actually work at ATK or did the company go to an online casting website to get this actor?

[JosephB]

Was trying to find current ATK info on DM-2 without luck but came across this dated document that was interesting, with some neat images. Delete if you feel the need to.

[Calphor]

So ATK is filming a glossy commercial for a static test firing.
No wonder that space has been that expensive all those years..

The question is: Does that Tom Cruise-wannabe actually work at ATK or did the company go to an online casting website to get this actor?

He actually works at ATK.

[zerm]

So ATK is filming a glossy commercial for a static test firing.
No wonder that space has been that expensive all those years..

It's corporate PR and every gov. contractor does it- it's not a big deal and not a big expence. Hell, I could make a similar quality vid. with the equipment I have here in my office and $75 worth of editing software. Space is expensive because cheap gets people killed, not because big contractors do PR videos. Please- let us find some other nit to pick.

[Space Pete]

Ignition time has changed to 10:27 AM CDT/3:27 PM GMT.

[Chris Bergin]

I'll have a look at this thread late tonight or early tomorrow to see about converting it to the live coverage pages, but we'll keep it on the Ares section regardless (I'll mirror a direction post in the live section).

Should be fun if the first firing was anything to go by (guy taking the key to the firing room etc).

[Chris Bergin]

Check out ATK's "trailer" for DM-2!

That's actually a really good video, very clever with the scene where the engineer is working at his desk, thinking about a "better future" with the photo of his family.

ATK also do the best Shuttle FRR presentations too

[Space Invaders]

From the objectives list:

"The [new materials used for the joints] will save significant weight".

Do we know exactly how much weight that is? And is this improvement specific to the 5-segment SRB, or can it be applied to the 4-seg as well?

[Downix]

From the objectives list:

"The [new materials used for the joints] will save significant weight".

Do we know exactly how much weight that is? And is this improvement specific to the 5-segment SRB, or can it be applied to the 4-seg as well?

IIRC, the work done on the 5-seg can carry over to the 4-seg, altho with the SLS some of the work will no longer be needed, like nozzles able to steer.

[edkyle99]

IIRC, the work done on the 5-seg can carry over to the 4-seg, altho with the SLS some of the work will no longer be needed, like nozzles able to steer.

SLS, like STS, will need TVC on the solids.  What it won't need is independent roll control, like Ares I.

 - Ed Kyle

[TrueBlueWitt]

IIRC, the work done on the 5-seg can carry over to the 4-seg, altho with the SLS some of the work will no longer be needed, like nozzles able to steer.

SLS, like STS, will need TVC on the solids.  What it won't need is independent roll control, like Ares I.

 - Ed Kyle

According to previous work by the DIRECT team.. they have Sufficient TVC just gimballing SSMEs.. TVC is NOT required on the solids.

I would post a link, but the search engine on this site is just attrocious.. I have NEVER found anything I was looking for with it!

[PahTo]

I've raised this question in a couple other threads, so I'll try here.

What is the best performance we can expect from an "uprated" (R)SRM?
That is, with reduced or no TVC hardware, and using HTPB instead of PBAN, what will/can the Isp be (recoverable 4-seg booster)?

(Bonus:  is it true that HTPB is actually a lower performance, but better Isp because it burns cooler and thus doesn't need such heavy casing?)

Thanks!

[Chris Bergin]

I would post a link, but the search engine on this site is just attrocious.. I have NEVER found anything I was looking for with it!

Some people seem to be able to work out the trick of the forum search, but I'm the same as you Mark is working on a new forum in the background, so hopefully that'll sort it out.

[Lars_J]

SLS, like STS, will need TVC on the solids.  What it won't need is independent roll control, like Ares I.

 - Ed Kyle

According to previous work by the DIRECT team.. they have Sufficient TVC just gimballing SSMEs.. TVC is NOT required on the solids.

First of all "The DIRECT team" is NOT an official authority on the matter. They are not the NASA SLS design team.

You've got to take everything the DIRECT team says with a pinch of salt. Sure, they claim to have NASA engineers that have helped them with their numbers. But until those individuals step forward, who knows? And even if they are who they claim to be, perhaps they are not 100% correct? A lot of what they say make a lot of sense, but you have to be skeptical.

[edkyle99]

IIRC, the work done on the 5-seg can carry over to the 4-seg, altho with the SLS some of the work will no longer be needed, like nozzles able to steer.

SLS, like STS, will need TVC on the solids.  What it won't need is independent roll control, like Ares I.

 - Ed Kyle

According to previous work by the DIRECT team.. they have Sufficient TVC just gimballing SSMEs.. TVC is NOT required on the solids.

No big throat solid has ever used a fixed nozzle, to my knowledge.  Consider Titan III, Titan 34D, Titan IVA, Titan IVB, STS, Ariane 5, H-II, H-IIA, H-IIB, and GSLV Mk3, for starters. 

 - Ed Kyle

[edkyle99]

Press Release describing tomorrow's DM-2 test.

 Ares 5 Segment SRB Firing

Alliant Techsystems (NYSE:ATK) and NASA will test the second fully developed Ares five-segment solid rocket motor, known as Development Motor-2 (DM-2). The five-segment rocket motor is an upgraded version of the Shuttle's 4-segment booster, and has also been identified as a key element of NASA's future Heavy Lift Launch vehicle.

Horizontal ground test firing of Ares

What: DM-2

Date: Tuesday August 31, 2010

Time: 9:05 a.m. MDT ATK Aerospace Systems facility in

Where: Promontory, Utah

Test Objectives/Background:

-- A total of 53 design objectives will be measured through more than 760 instruments.

-- DM-2 is a "cold motor" test. The motor will be cooled to 40 degrees F to measure solid rocket motor performance at low temperature, as well as to verify design requirements of new materials in the motor joints. These new materials will allow for the elimination of joint heaters that were necessary in the original 4-segment motor design. This will save significant weight, further reduce system complexity and simplify launch operations
, while simultaneously delivering increased operating margins at lower ambient temperatures.

-- Other objectives include data gathering on vital motor upgrades such as the new insulation and motor case liner and the redesigned nozzle which increase the robustness of the design.

-- When fired, the motor will produce a maximum thrust 3.6 million pounds, or 22 million horsepower.

-- The cases have all previously flown on the space shuttle, collectively launching on 57 missions.

-- A public viewing area is available along State Road 83 North approximately 20 miles west of Corinne, Utah.

CONTACT: Trina Patterson, +1-801-699-0943, [email protected], or George Torres, +1-801-699-2637, [email protected]

ATK Note to Editor: Media passes are required; contact Trina Patterson at (801) 699-0943 or [email protected]. -- Foreign media requests must be submitted by 4 p.m. MDT on August 16 -- All other media requests must be submitted by 4 p.m. MDT on August 27 -- Remote still cameras will need to be approved in advance and set up a day before the test -- Reporters will need to be on site by 6:00 a.m. the day of the test to be escorted to the viewing site. -- The media will be located in a viewing site optimal for photos and video. -- A press conference will be held 45 minutes following the test -- One-on-one interviews at the motor will be available after the firing -- Broadcast: Live equipment needs to be scheduled in advance to arrange for parking -- Satellite coordinates for downlink -- 9 MHz Ku band -- Satellite: Galaxy 28 (89 degrees west) -- Transponder: 17K Slot "D" -- Uplink: 14353.500 (H) -- Downlink: 12053.500 (V) -- Data: 8.448

Date: Tuesday, August 31, 2010

Location: Promontory, UT, US

 - Ed Kyle

[Jim]

IIRC, the work done on the 5-seg can carry over to the 4-seg, altho with the SLS some of the work will no longer be needed, like nozzles able to steer.

SLS, like STS, will need TVC on the solids.  What it won't need is independent roll control, like Ares I.

 - Ed Kyle

According to previous work by the DIRECT team.. they have Sufficient TVC just gimballing SSMEs.. TVC is NOT required on the solids.

No big throat solid has ever used a fixed nozzle, to my knowledge.  Consider Titan III, Titan 34D, Titan IVA, Titan IVB, STS, Ariane 5, H-II, H-IIA, H-IIB, and GSLV Mk3, for starters. 

 - Ed Kyle

Titan III, Titan 34D, Titan IVA were fixed nozzles.  TVC was by fluid injection.

[edkyle99]

IIRC, the work done on the 5-seg can carry over to the 4-seg, altho with the SLS some of the work will no longer be needed, like nozzles able to steer.

SLS, like STS, will need TVC on the solids.  What it won't need is independent roll control, like Ares I.

 - Ed Kyle

According to previous work by the DIRECT team.. they have Sufficient TVC just gimballing SSMEs.. TVC is NOT required on the solids.

No big throat solid has ever used a fixed nozzle, to my knowledge.  Consider Titan III, Titan 34D, Titan IVA, Titan IVB, STS, Ariane 5, H-II, H-IIA, H-IIB, and GSLV Mk3, for starters. 

 - Ed Kyle

Titan III, Titan 34D, Titan IVA were fixed nozzles.  TVC was by fluid injection.

Roger that.  Fixed nozzles on those.  But they did provide steering via. the fluid injection method.  I should have said "non-steering" rather than "fixed nozzles".

I can't imaging how an LV with two SRBs, be they four or five segments, could have control authority without those boosters steering.  Even with four SSMEs, the solids would still provide more than 80% of the liftoff thrust.

 - Ed Kyle

[Chris Bergin]

Will start a new thread in about three hours. Will have an article, including some latest info on SD HLV to beef things up - especially after even ATK note "has also been identified as a key element of NASA's future Heavy Lift Launch vehicle" in their materials now.

[madscientist197]

I can't imaging how an LV with two SRBs, be they four or five segments, could have control authority without those boosters steering.  Even with four SSMEs, the solids would still provide more than 80% of the liftoff thrust.

Why? It's not like the vehicle needs to be able to do a backflip in a few seconds or anything. The minimum steering requirements would be set by wind and other asymmetric loading conditions (e.g. SRB tail-off). For general steering you only need to be able to slightly perturb pitch, yaw and roll etc. as you can trade off control authority versus time to manuever. There's generally little requirement for a vehicle to be able to steer fast. I doubt many vehicles use their full steering control authority...

[robertross]

Will start a new thread in about three hours. Will have an article, including some latest info on SD HLV to beef things up - especially after even ATK note "has also been identified as a key element of NASA's future Heavy Lift Launch vehicle" in their materials now.

Cool.

I wonder if that is just a sales pitch, or a 'negotiated'* settlement to move things forward in the HLV arena based on the latest happenings. Time will tell.

*speculation

[Jim]

(e.g. SRB tail-off).

That is the reason for the need

[MikeMi.]

http://forum.nasaspaceflight.com/index.php?topic=22617.msg632941;boardseen#new

[Generic Username]

DM-2 crapped all over my house.

At first I was like: http://up-ship.com/blog/?p=6964

But then I was all: http://up-ship.com/blog/?p=6970

[PahTo]

Wow--thanks for sharing, Generic Username.  With all the warnings given during a shuttle launch (exhuast is acidic, etc etc), I wonder about the pH of the dirt...

Well, if your lawn furniture dissolves, it's only "so bad".  Now if your mailbox dissolves...
;-)

[Generic Username]

I wonder about the pH of the dirt...

Whatever it is, it's damned sticky. It was a perfectly dry day... no dew on the ground, not a cloud in the sky, yet it sticks like mud. About four hours later, with the sun shining and the wind blowing pretty hard... there's not the slightest evidence of the stuff blowing away. I expect rain will eventually take care of it, though.

Well, if your lawn furniture dissolves, it's only "so bad".  Now if your mailbox dissolves...

Then I'm *definitely* putting the stuff on eBay.

[Lars_J]

Yikes! Hopefully that's just plain dirt and not the toxic stuff.

[PahTo]

Thanks for the info, Jim.  Could this be handled by single-axis TVC (what I call reduced TVC hardware), or are we talking the same/similar package that currently flies on STS?

(e.g. SRB tail-off).

That is the reason for the need

[robertross]

Then I'm *definitely* putting the stuff on eBay.

I think you should!

(to help pay for those clean-up costs!) 

sorry to hear about your 'mess'.

[Generic Username]

Yikes! Hopefully that's just plain dirt and not the toxic stuff.

A neighbor has complained that where the specks of dirt were on some of her garden plants, the leaves have been bleached white.

So I'm sure it's *fine.*

[Lars_J]

Yikes! Hopefully that's just plain dirt and not the toxic stuff.

A neighbor has complained that where the specks of dirt were on some of her garden plants, the leaves have been bleached white.

So I'm sure it's *fine.*

Umm 

[robertross]

Yikes! Hopefully that's just plain dirt and not the toxic stuff.

A neighbor has complained that where the specks of dirt were on some of her garden plants, the leaves have been bleached white.

So I'm sure it's *fine.*

*cough cough*  *wheez wheez*

I'd be taking a vacation at this point...in fact, a day 'prior' to launch.

Part of the EPA issues with solids.

Political reality never equalled common sense. They do need to replace these solids with all-liquid boosters....

...some day.

[Generic Username]

They do need to replace these solids with all-liquid boosters....

Indeed so. But for a first stage booster, you kinda need the propellant to be dense-ish, to help reduce the size of the vehicle, so hydrogen is right out. And kerosene, methane, propane and the like are known producers of the evil, evil carbon dioxide, so those are out. So, clearly we are left with a booster fueled with hydrazine and fluorine.

It'll be *fine,* don't worry.

[Generic Username]

*cough cough*  *wheez wheez*

Actually, directly related to *that* point, was this earlier ATK escapade:

http://up-ship.com/blog/?p=2514

[robertross]

They do need to replace these solids with all-liquid boosters....

Indeed so. But for a first stage booster, you kinda need the propellant to be dense-ish, to help reduce the size of the vehicle, so hydrogen is right out. And kerosene, methane, propane and the like are known producers of the evil, evil carbon dioxide, so those are out. So, clearly we are left with a booster fueled with hydrazine and fluorine.

It'll be *fine,* don't worry.

Not the thread for it, but I would say that hydrocarbons are not out. They are still the best bet when weighing the pros & cons (technically, not politically...for now).

[chrisking0997]

I <3 this thread...

[edkyle99]

... I would say that hydrocarbons are not out. They are still the best bet when weighing the pros & cons (technically, not politically...for now).

Technically, yes, but the projected development cost has killed the kerosene idea from a political standpoint.  There isn't any money.  For super-heavies, it is going to be SRB or nothing.  And it really isn't clear to me that there is even enough money for the SRB based super-heavy. 

 - Ed Kyle

[Generic Username]

Some local news coverage:
http://www.abc4.com/news/local/story/ATK-fallout/Jv5DnBUzBEu8uBF3adO9fw.cspx

Jana Burdick's husband was working outside when the fallout covered him.

“It did burn him a little bit on his skin,” she said. “There was ash covering everywhere.”

"You really don't want to be playing in it but at the same time it's really not hazardous or toxic,” said DEQ spokesperson Donna Spangler.

[spaceman10]

What was the change in the exit cone design?

[robertross]

What was the change in the exit cone design?

IIRC, one of the changes was to make it longer to improve performance.

[edkyle99]

What was the change in the exit cone design?

The nozzle throat diameter was increased, to handle the higher ejected mass rate (increased thrust). 

In addition, the propellant grain shape was modified to alter the propellant burn rate.  Insulation between the propellant and the casing was also modified.  There was talk about a longer nozzle at one point, to improve specific impulse, but I'm not sure that was implemented.

 - Ed Kyle

[PahTo]

What is the Isp of the 5-seg PBAN booster?  And what is the expected Isp of a 5-seg HTPB?  It sounds like two-axis TVC will be required for all variants of HLV...
Thanks!

The nozzle throat diameter was increased, to handle the higher ejected mass rate (increased thrust). 

In addition, the propellant grain shape was modified to alter the propellant burn rate.  Insulation between the propellant and the casing was also modified.  There was talk about a longer nozzle at one point, to improve specific impulse, but I'm not sure that was implemented.

 - Ed Kyle

[sdsds]

what is the expected Isp of a 5-seg HTPB?

I think there's no hard number because there is no expectation that SDHLV/SLS will move away from the current propellant in the near term.  At least, there doesn't seem to be funding in any of the budget proposals for further development of SRB technology beyond the current 5-seg Ares-I contract.

Specifically as regards the technology in DM-2, can anyone say for certain if all the components used for this motor were at least candidates for the qualification motors?  Or were some still Shuttle-legacy technology that will be replaced before the qualification effort starts?

[edkyle99]

What is the Isp of the 5-seg PBAN booster?  And what is the expected Isp of a 5-seg HTPB?  It sounds like two-axis TVC will be required for all variants of HLV...
Thanks!

My notes say 237s sea level, 265.5 sec vacuum for the existing PBAN, but I believe those numbers were squishy.  The longer nozzle would have moved the vacuum ISP up beyond 270 sec, perhaps near 275 sec.  Not sure about HTPB.

 - Ed Kyle

[jacqmans]

News Release Issued: October 27, 2010 8:00 AM EDT

ATK and NASA Report Initial 30-Day Findings From Development Motor (DM-2)
Data Confirm ATK Five Segment Solid Rocket Motor is Ready for Flight Testing
Five-Segment Design Matures to Support Future Launch Vehicles with Significant Performance Improvements at Reduced Cost
PROMONTORY, Utah, Oct. 27 /PRNewswire/ -- Data from the second successful five segment Development Motor (DM-2) test conducted by ATK (NYSE: ATK) and NASA show that the new motor performed precisely as designed, providing substantially higher performance and reliability than the heritage space shuttle solid rocket booster at a lower cost.

"These extensive test results confirm the ATK five segment Solid Rocket Motor (SRM) is ready for flight testing," said Charlie Precourt, vice president and general manager of Space Launch Systems, ATK Aerospace Systems.  "The five-segment first stage design was based on more than 30 years of safety-driven improvements on the shuttle program. The result is a higher performing, more reliable solid rocket motor, which equates to increased safety for crew and mission success for cargo."

The 30-day findings from the August 31 ground test were compared to data collected from the first ground test (Sept. 2009) and the Ares I-X flight test (Oct. 2009) to develop a greater understanding of motor and material performance and first stage avionics. The data were also compared to ground test, flight, and post-flight data collected throughout the Space Shuttle Program.

Modifications to the motor include an added fifth segment, changes to the propellant grain, a larger nozzle opening, and an upgraded liner and insulation — all designed to meet performance requirements and increase reliability while lowering manufacturing costs.

"We were able to incorporate many design changes during the five-segment development that we identified during the shuttle program but were not able to make given the shuttle vehicle's operations tempo," said Precourt. "We also incorporated materials and streamlined processes that have been flight-proven in our commercial programs."

Propellant grain changes included an additional fin to provide the necessary thrust profile at liftoff and changes to propellant angles at joints to increase structural safety factors. The ballistics data from DM-2 were exactly in line with predictions.

The new insulation and liner is made of environmentally-friendly material that replaces the obsolete asbestos-based insulation used on shuttle. Advantages include improved thermal properties and lower density, offering 10 percent or 2,000 pounds in weight savings, which allows for heavier payloads. Process improvements developed with the new green material have also yielded safety and schedule benefits. Results from DM-2 showed the new liner provided higher thermal protection than the shuttle motors.

New low-temperature O-rings enabled the elimination of joint heaters and the associated cabling and infrastructure. This lowers joints complexity, thereby eliminating additional failure modes, and saves 500 pounds in weight, while providing a stronger seal than previous O-rings.

A main objective of DM-2 was to test the new O-rings at cold temperatures. The motor was conditioned to approximately 40 degrees F., and flaws were introduced into the joints that allowed hot gases to potentially penetrate the insulation into the joint and thermal protection system where the O-rings are housed. Even under those conditions, the seal and thermal protection system on DM-2 performed as designed.

"We are very pleased with the initial data collected from DM-2," said Precourt. "It shows the performance of the motor and components either met or exceeded our predictions."

Thrust oscillation is another area where DM-2 results are significantly better than initial models predicted. Through combined DM-2, DM-1 and Ares I-X results, and with computational fluid dynamics analyses, NASA and ATK engineers have learned the behavior attributed to thrust oscillations in five-segment solid rocket motors is 30 to 60 percent less than previously predicted. Specifically, the DM-1 and DM-2 data indicate that this motor is very quiet, producing very low pressure oscillations.  Also Ares I-X showed that in flight, the overall structure of that configuration is less susceptible to excitation than previously expected.

The technical and material improvements to the motor, combined with new tools and streamlined processes, have enabled ATK to produce motors at a lower cost.

As the prime contractor for the five-segment motor first stage, ATK continues to perform on schedule and within cost to support NASA's space exploration programs. ATK is currently maturing the first stage avionics, and will complete a critical design review in the fall of 2011.

ATK is a premier aerospace and defense company with operations in 24 states, Puerto Rico, and internationally, and revenues of approximately $4.8 billion.  News and information can be found on the Internet at www.atk.com.

[robertross]

News Release Issued: October 27, 2010 8:00 AM EDT

{snip}
"We are very pleased with the initial data collected from DM-2," said Precourt. "It shows the performance of the motor and components either met or exceeded our predictions."

Really??

L2 says differently... 

[renclod]

launch, baby, launch !

[Calphor]

News Release Issued: October 27, 2010 8:00 AM EDT

{snip}
"We are very pleased with the initial data collected from DM-2," said Precourt. "It shows the performance of the motor and components either met or exceeded our predictions."

Really??

L2 says differently... 

Link?

[robertross]

News Release Issued: October 27, 2010 8:00 AM EDT

{snip}
"We are very pleased with the initial data collected from DM-2," said Precourt. "It shows the performance of the motor and components either met or exceeded our predictions."

Really??

L2 says differently... 

Link?

Part of the STS-133 documentation on L2:

http://forum.nasaspaceflight.com/index.php?topic=23127.0

[rdale]

I see the RSRM presentation - but I don't see where it says the motor didn't perform up to predictions? Unless I'm reading page 4 wrong where it says "motor performance predicted to be nominal - well within family and requirements"?

[robertross]

I see the RSRM presentation - but I don't see where it says the motor didn't perform up to predictions? Unless I'm reading page 4 wrong where it says "motor performance predicted to be nominal - well within family and requirements"?

Well it (issue) has no bearing on the 4-segment design, which is the intent of that presentation. But to this discussion, and how PR is saying "It shows the performance of the motor and components either met or exceeded our predictions." is not entirely correct.

[Space Pete]

I see the RSRM presentation - but I don't see where it says the motor didn't perform up to predictions? Unless I'm reading page 4 wrong where it says "motor performance predicted to be nominal - well within family and requirements"?

Well it (issue) has no bearing on the 4-segment design, which is the intent of that presentation. But to this discussion, and how PR is saying "It shows the performance of the motor and components either met or exceeded our predictions." is not entirely correct.

Remember, this is a public press release, not an internal memo - even if the results were not what they were expecting, they're not going to admit it, and certainly not in the current climate.

[renclod]

Remember, this is a public press release, not an internal memo - even if the results were not what they were expecting, they're not going to admit it, and certainly not in the current climate.

I don't get it ... "a public press release" is something thay they do in order to ... NOT "admit" issues ?! It does not make sense. Who/What is forcing both NASA and ATK to release a report that was patently false ?! They could simply shut up.

What are you guys talking about ?

[rdale]

Who/What is forcing both NASA and ATK to release a report that was patently false ?!

Fill me in please - what is patently false about the press release?

[renclod]

Who/What is forcing both NASA and ATK to release a report that was patently false ?!

Fill me in please - what is patently false about the press release?

That is my question.
robertross reports that the press release is false - not me.

[phred]

I don't suppose ATK has released a thrust vs. time graph for DM-1 or DM-2?

[sdsds]

Quick note:  ATKRocketNews (Trina Patterson) has begun tweeting DM-3 status:
"The center forward segment has been moved into ATK's test stand preparing for ground test of the 5-segment SRB in UT this fall" and  "We stack the 5-segment SRB horizontally in the test stand from top-down; unlike vertical stacking @KSC were it's from the bottom-up"