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Ricardo

Posts: 13289
Joined: Dec. 14 2004
From: Washington DC

RE: Black Hole eats sun (in reply to Piwin

Well if you are budgeting for things that ARENT EVEN SUPPOSED TO OCCUR, then you are “over budgeting” as I said earlier. That is what YOU seem to want, and as I said, if you do a lot of that, then you won’t get anything off the ground.

_____________________________

CD's and transcriptions available here:
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  REPORT THIS POST AS INAPPROPRIATE |  Date May 23 2022 13:09:41
 
Piwin

Posts: 3376
Joined: Feb. 9 2016
 

RE: Black Hole eats sun (in reply to Ricardo

Yeah, we're not really getting anywhere. Agree to disagree, I guess. Just to illustrate that I'm not pulling this out of my ass, here's one small chapter in JWST history, the report of the ICRP, the independent panel of experts that was tasked with reviewing what was wrong in the late 00s:

https://www.nasa.gov/pdf/499224main_JWST-ICRP_Report-FINAL.pdf

Even if you just read the short Executive Summary you'll see that this isn't some wild accusation I'm making at poor innocent engineers, as if I was somehow blaming them for not being able to predict the future. A lot goes into mission planning. Reducing it to "you can't predict the future" is simplistic and just leads to rather pointless binary discussions between that position and devilhand's position of "it's expensive so let's scrap it all".

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"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
  REPORT THIS POST AS INAPPROPRIATE |  Date May 23 2022 17:16:43
 
Ricardo

Posts: 13289
Joined: Dec. 14 2004
From: Washington DC

RE: Black Hole eats sun (in reply to Piwin

I didn’t accuse you of making a “wild accusation”. But rather, what you WANT is OVER BUDGETING…and it is exactly what was recommended in hind site of the problems:

quote:

For a project as challenging as JWST, in a portfolio without substantial flexibility, an 80% confidence budget would more likely represent a most probable cost, including maintaining 25% reserves in each year to deal with unanticipated problems.
. That OVER the standard 70/20.

So there you have it…and this type of wishful thinking would have put the project on the back burner for long enough that the limited funds allocated would have prioritized the doable projects way up front, and the scientists ready to do the analysis will all have died of old age by the time the proper funding comes in (if ever). Instead they pushed the thing along and squeezed the lemon for every drop they could along the way and got her done.

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date May 24 2022 13:12:35
 
Piwin

Posts: 3376
Joined: Feb. 9 2016
 

RE: Black Hole eats sun (in reply to Ricardo

Yeah, I guess I'm just not getting my point across, because my point is certainly not that they should overbudget.

All I'll say is to have a look at the full 22 recommendations of the report. As far as I can tell, there are only 2 that could be interpreted as "overbudgeting" (though I personally wouldn't. Corrective measures for underbudgeting are not "overbudgeting"...). They repeatedly point to problems that have nothing at all to do with "unanticipated problems", problems that stemmed from causes that were already known at the time (or that could have been known had the proper audits/analyses been performed), problems that were procedural, structural, policy-related, etc. Solve those problems and you remove a lot of the hurdles that get in the way of the project teams. Solve those problems and the project ends up cheaper, faster and easier for everyone working on it. Solve those problems and you'll be in a much better position to argue against the naysayers when the **** really hits the fan, like your example with Hubble.

Fortunately NASA didn't consider those recommendations to be wishful thinking, since they ended up implementing many of them (not sure how to handle a counterfactual like saying that requiring an 80% confidence rate and 25% contingency would have put the project on the back burner. All I can say is that they ended up implementing that recommendation, so at the very least it was within the realm of possibilities for them at that point in time). One could argue that it was too little too late, but at least it was an improvement.

https://jwst.nasa.gov/resources/JamesWebbSpaceTelescopeIndependentComprehensiveReviewPanelReport.pdf

_____________________________

"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
  REPORT THIS POST AS INAPPROPRIATE |  Date May 24 2022 16:45:20
 
Richard Jernigan

Posts: 3202
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Black Hole eats sun (in reply to Piwin

I spent 43 years working on defense contracts, mainly with the U.S. Air Force and the U.S. Navy, but also with the British Atomic Weapons Research Establishment, and the Ministries of Defense of the U.K. and another country. I also participated in the first flights of SpaceX at Kwajalein as Radar Test Director. SpaceX’s expenditure from inception to orbit was $100-million of Musk’s own money. The Kwajalein Modernization and Remoting program, to upgrade four of the planet’s most powerful and complex radars came in at a little over $200-million, from an initial estimate of $100-million. These were the smallest projects I worked on.

Others included the Strategic Defense Initiative (SDI, “Star Wars”) and every ICBM system development on our side, starting with Minuteman II. I worked on numerous proposals.

First I would observe that the James Webb Space Telescope ICRP estimate to complete was $6.5-billion. The actual cost of $10-billion was only 1.5 times over this estimate, rather than the factor of 2 overrun cited as poor planning by Piwin.

During my last 18 years I worked for three different contractors at Kwajalein Missile Range/Reagan Test Site in the Central Pacific. I was responsible for about half the technical content of two $1.5-billion proposals for staffing the range. Staffing of the missile range carried low technical and cost risk, so the contractor’s fee was low, and cost overruns were nearly zero.

On other projects, cost overruns of double the original estimates were not uncommon in some phases of the effort.

The first 25 years of my engineering career were in exploratory and advanced development of technology and systems to defeat the Soviet strategic missile defenses. For the last 15 years or so I was internationally recognized as a leader in the field, and involved in planning major projects.

CIA estimated that the USSR spent over 100-billion rubles on strategic missile defense. The penetration aids on the Minuteman II missile system cost about $200-million to defeat the Soviet defense, 1969 dollars.

The technology and systems development projects typically consisted of three phases: exploratory and advanced development, development of manufacturing processes and test, and production for deployment. During exploratory and advanced development various design concepts are explored. One concept is selected for detailed design and development. Hardware is built, tested and refined. This first stage carries the most technological risk: design ideas turn out not to work, unforeseen problems arise. This stage experiences the greatest cost and schedule overruns. But exploratory and advanced development cost much less than production, so the advanced development overruns are a small fraction of overall system cost.

The JWST is a one-off. Actual hardware fabrication was a much smaller fraction of the cost than production for an operationasl military system. The exploratory and advanced development overruns were nearly half of the eventual total system cost, by no means unusual in a project for extensive development of novel technology.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date May 24 2022 17:55:49
 
Piwin

Posts: 3376
Joined: Feb. 9 2016
 

RE: Black Hole eats sun (in reply to Richard Jernigan

quote:

the actual cost of $10-billion was only 1.5 times over this estimate


Just to clarify, the factor 2 was in reference to the JWST baseline in the confirmation review (which I believe is right after the round of PDRs, end of phase B, in NASA world? If I'm correct about that, then personally I think at PDR you should be able to give a solid ballpark estimate of the costs). That figure was around $5.1 billion, and later revised upwards following the ICRP recommendations. I did get the year wrong though, since the estimate comes from 2008, not 2009.

What I'm mostly arguing against is the line of thought that lumps everything into unforeseeable problems and says you can't expect any financial accountability at all in research projects. I don't think it's wise to communicate that way about these projects, especially when there are those who would like to scrap them altogether. Of course, internally they do take these problems seriously, and the fact that there even was an ICRP (and that its recommendations were followed) is proof enough.

After a quick glance at articles of the time, I think the ICRP chair, John Casani, struck the right chord. His message to the outside world was 1. It's hard to get these complicated projects right, and 2. there were faults in the previous budget and we're doing X, Y and Z to correct them. Saying 1. without 2. is in my opinion a mistake. Investors, whether private corporations or taxpayers, will expect some degree of accountability. Dismissing that expectation of accountability on the grounds that it's scientific research just won't fly. And if we persist in telling people that science=0 financial accountability, then there are some interesting scientific projects in the future that may quite literally not fly...

On a separate note, I would have loved to be a fly on the wall in some of the places you've worked. With my former work in languages, I had the opportunity to sit in on a variety of meetings related to space projects (ESA, CNES, Ariane, Thales, etc.). Hence some basic familiarity with what is involved in the budgeting process and with just how tense discussions on planning and financing can get. Unfortunately it was mostly in office rooms rather than on-site locations. When I was offered an assignment in Kourou (which paid surprisingly little but was appealing just to be able to see a bit of the action up close), it was unfortunately at a time where I was struggling with a crippling fear of flying, so I declined. By the time I had worked my way back up to being able to handle longer flights, I had already changed careers.

_____________________________

"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
  REPORT THIS POST AS INAPPROPRIATE |  Date May 24 2022 21:10:01
 
Richard Jernigan

Posts: 3202
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Black Hole eats sun (in reply to Piwin

Piwin-

I confess to being both sarcastic, and imprecise. I did not intend seriously to question your criticism of the JWST cost overrun. I just meant to point out the ICRP’s inability to predict the final cost much more accurately than the NASA budgeteers they criticized.

Under the U.S. Department of Defense contracting regulations of the late 20th century, the Preliminary Design Review reported upon the detailed design of the concept selected at the Conceptual Design Review. This design formed the baseline for physical testing. Up to this point the work had been almost entirely theoretical. The revolting developments began to happen when the preliminary design was built and physically tested. Unacceptable test results required analysis and redesign. Some reserves of time and money would be included in the original plan to accommodate analysis and redesign. The greatest cost and schedule uncertainty occurs after Preliminary Design Review, and before Final Design Review.

In my experience, more experienced organizations produced more accurate initial cost and schedule estimates. For example, before undertaking the Trident ICBM program, Lockheed Missiles and Space Company had executed development and production of Polaris and Poseidon. Raytheon had many successful radar technology and system development programs before their efficient and prompt production of the radar system for the present U.S. ICBM defense. These companies had a reputation for accurate cost estimates and on-time delivery. But the cited programs were incremental technology developments, not great leaps forward. These companies also had reputations as expensive and risk averse.

On the other hand, General Electric Reentry Systems Division had a solid record of developing ICBM reentry vehicles.
There were moderate cost and schedule overruns, but the technology was revolutionary. Improved accuracy enabled smaller warhead yields, smaller reentry vehicles, and the development of ICBMS carrying multiple independently targeted reentry vehicles.

But GE performed miserably on a contract for lightweight, subscale reentry vehicle decoys, which in my estimation required only moderate technological innovation. The brilliant innovators in reentry vehicle design had retired or moved on. GE was ill equipped in the art and science of decoy evaluation, and failed to bring in subcontractors with the requisite experience. And they made amateurish mistakes in design and test.

A few years ago Larisa and I visited the U.S. Space and Rocket Center in Huntsville, Alabama, which commemorates the development of the Saturn 5 moon rocket. The hardware on display is immense and impressive. I pointed out what I considered the most impressive display of all, a summary of the program plan. It was extremely risky, with little or no slack for redesign and retest. I said to Larisa, whose mother was an aeronautical engineer in the USSR, “This, and the amount of money thrown at it, is what impressed the Russians.”

“Aside from the money, why was the U.S.A. able to do it?”

“Von Braun and the Peenemunde brain trust made sure to surrender to us instead of being captured by the Soviets. We made sure they had enough earlier support to develop the ability to do this. It was a tour de force, but it was built on incremental development. As you know, the Soviets gained an initial lead in the space race, but lost it to catastrophic test failures and redesign delays.”

I know nothing about space telescope design and development, but NASA has repeatedly touted the JWST as revolutionary in both design and capability. The development of accurate cost and schedule eluded both the original NASA/ industry team and ICRP’s panel of outside experts. I can offer no diagnosis.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date May 24 2022 23:35:08
 
Piwin

Posts: 3376
Joined: Feb. 9 2016
 

RE: Black Hole eats sun (in reply to Richard Jernigan

quote:

sarcastic


Well that's embarrassing... I completely missed the point you were making. Sorry about that! It's probably for the best that I don't work as an interpreter anymore

_____________________________

"Anything you do can be fixed. What you cannot fix is the perfection of a blank page. What you cannot fix is that pristine, unsullied whiteness of a screen or a page with nothing on it—because there’s nothing there to fix."
  REPORT THIS POST AS INAPPROPRIATE |  Date May 25 2022 13:56:08
 
Ricardo

Posts: 13289
Joined: Dec. 14 2004
From: Washington DC

RE: Black Hole eats sun (in reply to Richard Jernigan

Sorry for the aside but the minute man references got me going down the rabbit hole of the Teller device mechanism. I know it is a top secret thing, but the idea seems to be that the final fission stage of the tamper casing is what amounts to the vast majority of the destructive force (plus perhaps fission of the entire radiation casing) in the range of 50% or more? What is hard to wrap my head around is how could that be if X-ray Ablation occurs first, in order to crush the spark plug that initiates the fusion. I guess the timeline is vague to me (I know it is fast, but is it fast enough?) such that tritium production (fusion) can send neutrons (sub light speed) fast enough to fission what is left of the tamper AFTER the ablation? Does Ablation not imply total destruction of the tamper material? In addition, a bizarre description based on photo evidence of a “neutron gun array” directed at the second stage component??? I assume that would be helping the ablation stage, or maybe slow enough to add to the final fission?? I don’t get it. (And i feel dirty talking about it )

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date May 27 2022 18:11:48
 
JasonM

Posts: 1783
Joined: Dec. 8 2005
From: Baltimore

RE: Black Hole eats sun (in reply to Ricardo

The key top secret ingredient is styrofoam packing peanuts. Clear disregard for the environment here.

https://en.m.wikipedia.org/wiki/Thermonuclear_weapon
  REPORT THIS POST AS INAPPROPRIATE |  Date May 27 2022 19:00:04
 
Richard Jernigan

Posts: 3202
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Black Hole eats sun (in reply to Ricardo

Sorry, you seem to be better informed about thermonuclear weapon design than I am.

I could plead the Sherlock Holmes defense, but it would not be precisely accurate. As you probably know, Watson was astonished to find that Holmes did not know the Earth orbited around the Sun. Holmes propounded the theory that memory had a strictly limited capacity. Once it was full you needed to forget a fact in order to learn a new one. Holmes remembered only those facts necessary for his profession, the detection of crime.

In my case the limiting resource was time. I was so busy carrying out my responsibilities I didn’t delve into those of many others. My job was to get the bombs past the Soviet defenses. It was up to others to design the thermonuclear explosives.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date May 29 2022 19:42:28
 
Ricardo

Posts: 13289
Joined: Dec. 14 2004
From: Washington DC

RE: Black Hole eats sun (in reply to JasonM

quote:

ORIGINAL: JasonM

The key top secret ingredient is styrofoam packing peanuts. Clear disregard for the environment here.

https://en.m.wikipedia.org/wiki/Thermonuclear_weapon


I guess it means the styrofoam peanut plasma holds the tamper “together” enough after ablation so the fast neutrons from the tritium fusion can fission what is left there. Maybe the failed Castle Koon shot was related to the difficulty of controlling that second stage (they admit a design flaw that caused too fast ie unfocused collapse of the second stage). Seems to me the lack of info on the mechanism design is in hopes the “enemies” run into the same trouble (fizzle).

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date May 30 2022 16:35:16
 
Richard Jernigan

Posts: 3202
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Black Hole eats sun (in reply to Ricardo

quote:

ORIGINAL: Ricardo

Does Ablation not imply total destruction of the tamper material?



No. The Wikipedia article claims that ablation of about 3/4 of the tamper material is the most efficient case. I don’t understand why 3/4 is most efficient. But ablation calculations are relatively straightforward. I needed to understand and use them in a different context. Sandia Corp in Albuquerque NM had a supercomputer app to do the calculations in the late ‘60s, and underground nuclear tests at the Nevada Test Site verified the results.

To expose materials to heavy doses of thermal X-rays, a blast chamber and tunnel are excavated. A nuclear device is installed in the blast chamber. Test materials are installed in the tunnel, their distance from the nuclear device according to the dose required. Blast doors between the device and the samples allow the radiation to pass, but close soon enough to keep material debris for damaging the samples.

After the explosion people entered the tunnel to retrieve the samples. One of my good friends was given this task. He suited up in anti-contamination gear with a full face mask and a supply of air to breathe. While in the tunnel he began to feel dizzy and feverish, an alarming development. He has a degree in nuclear engineering and was familiar with the symptoms of radiation sickness.

He’s about my age, and shows no ill effects of his adventure, so far.

Turned out he was coming down with the flu.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date May 30 2022 19:24:51
 
Ricardo

Posts: 13289
Joined: Dec. 14 2004
From: Washington DC

RE: Black Hole eats sun (in reply to Richard Jernigan

quote:

No. The Wikipedia article claims that ablation of about 3/4 of the tamper material is the most efficient case. I don’t understand why 3/4 is most efficient.


Right, so only 1/4 of it is squeezing in on the spark plug…so after fusion occurs, that 1/4 left over might fission, but since it is separated from the other 3/4, is that small amount enough fission to account for 50% of the descructive force??? That is what had me scratching my head.

_____________________________

CD's and transcriptions available here:
www.ricardomarlow.com
  REPORT THIS POST AS INAPPROPRIATE |  Date May 31 2022 12:20:59
 
mrstwinkle

 

Posts: 487
Joined: May 14 2017
 

RE: Black Hole eats sun (in reply to Richard Jernigan

Sounds like the plot of the game Half Life
  REPORT THIS POST AS INAPPROPRIATE |  Date May 31 2022 17:36:26
 
Richard Jernigan

Posts: 3202
Joined: Jan. 20 2004
From: Austin, Texas USA

RE: Black Hole eats sun (in reply to Ricardo

quote:

ORIGINAL: Ricardo

quote:

No. The Wikipedia article claims that ablation of about 3/4 of the tamper material is the most efficient case. I don’t understand why 3/4 is most efficient.


Right, so only 1/4 of it is squeezing in on the spark plug…so after fusion occurs, that 1/4 left over might fission, but since it is separated from the other 3/4, is that small amount enough fission to account for 50% of the descructive force??? That is what had me scratching my head.


Two thermonuclear devices whose effects (not design) I frequently studied were the 300 kiloton warheads of some U.S. ICBMs and the estimated 1 megaton warheads of Soviet exoatmospheric interceptors.

Fissioning uranium produces about 17 kilotons of energy per kilogram of uranium. A little arithmetic gives 35kg for the pre-ablation mass of the tamper of the U.S. warhead, 59kg for the Soviet.

Uranium density is about 19 grams/cubic centimeter. This requires 1,858 cubic centimeters of uranium for the 300 kt warhead, 3096 cc for the 1 megaton device. To give a feel for the size, this amount of uranium would fit in a cube 4.76 inches on a side for the smaller warhead, 5.74 inches for the larger, pre-ablation.

The fission of these relatively small amounts of uranium is driven by neutrons from the fusion reaction, not by critical mass uranium neutrons as in the explosive-compressed trigger.

I have no practical experience with this subject, so someone should at least check my arithmetic.

RNJ
  REPORT THIS POST AS INAPPROPRIATE |  Date May 31 2022 18:01:16
 
JasonM

Posts: 1783
Joined: Dec. 8 2005
From: Baltimore

RE: Black Hole eats sun (in reply to Richard Jernigan

The wiki also says that the whole Radiation case is made of fissile material. Is that “radiation case” the outer shell enclosure of the whole warhead? Maybe it’s not enriched uranium so as not to give off high levels of radiation just parked atop a missile on a submarine… idk?
  REPORT THIS POST AS INAPPROPRIATE |  Date Jun. 1 2022 0:43:57
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