---By "model" I mean a numerical CFD model, not a physical object. And yes, you need those models in order to design spacecraft and ensure their safe operation. You need those models in order to determine how the plumes behave and interact with their environments. Part of my job is to provide the tools for just such determinations. My customers pay me for it because they really do need it. ----

Jay, I know what kind of model you meant, they are used in weather forecasting every day. Models are forecast and forecast are fowl-able. We have models of what the weather is going to do and quite often, the model is incorrect. What I was saying to you was we have lots of footage showing alleged landings and take offs. We now have actaul data (allegedly) and no longer need the model. After seeing some of this footage, if it is real, you won't convince me that the soft loose upturned soil of the landing probe was not visibly and noticably affected.


Jay wrote - It only stands to reason...

...i.e., "Based on my inexpert opinion"...

in the strange alien environment of the moon

Now I'm smiling, I only used that statement because it so often comes from your side of the argument (not from you but other Hoax Busters) that the things that are not explainable are due to the "strange alien environment of the moon). Sorry, I shouldn't't lump you in with them either as I ask of you....

Jay wrote -
Impacting where on the surface? How hard? Spreading outward how far? With what distribution? At what departure angle? The answers to your questions -- and to the arguments you've based on them -- are available only through the type of model you've rejected. You're operating way down on the "rocket make lots of fire" level and pretending that that's a sufficient understanding to rule on authenticity.

I'm trying to raise your level of understanding, but you don't seem interested.



I guess I'm just comparing pictures to movies to testimony. I watch the footage of 16 landing and it appears they have thrust all the way down tog touchdown. Now, it also appears they killed the engine just after probe contact as they let out a good "whoo" and the video show a pretty solid bounce. Then engine appeared to be moving quite a sufficient amount of soil at touchdown, heavy and thick. Hence, if 11 had ignition all the way to the surface, I am having a hard time understanding why the soil is so unaffected....ie the probe soil displacement along with the little mound of soil built up on the inside of the pad that has been pointed out. You mentioned 2500 lbs of thrust at touchdown. I'd be willing to venture to say on 11 it was a little more. Either way, 2500 lbs is a significant blast. Your right, I don't know the complete affects of a zero atmosphere on that type of blast, I'm using the video footage to grasp that understanding on 15, 16, and 17 since I have conceded those flights probably did operate as scheduled and the LEM didn't power plant didn't change significantly from 11 to 17. They were kicking up some serious dust when they landed.

Jay wrote -
You seem to want to abandon all rigor and just form uneducated opinions about what you see in selected evidence. Fine, but don't have any delusions that this "proves" anything except that a little knowledge is a dangerous thing.

If you want to argue that the triangle impression is anomalous because the surface would have been swept clean, then show me your fluid dynamics results. Don't just wave your hands and declare it would be so. Don't just make vague references to things you think are relevant just because they share a few similarities. The flour experiment was meant to illustrate the qualitative difference between fluid pressure and mechanical pressure, but instead of trying to learn from it you just ridiculed it. Maybe you should go back and think about it again before you post further.



No Jay, I still own the same horse I rode in on. The picture anomaly I am still at odds with is the fact the soil from the probe has spilled over and on top of the print. The other fact that came to light during that discussion (same horse) when you pointed out the dust under the pad indicated a slide. I merely am questioning (same horse) how and why the dust you use as your evidence, appears to be undisturbed by the thrust of the LEM as it landed. I agree with you that engine shutdown might have occured just before pad contact, they cannot pinpoint the exact time I know. No, I don't have the kind of model you mention, I just look at the dust displacement during landing from alleged actual videos. Given that, no one has adequately explained the probe displacement overlaying the print. That horse is in the barn unless someone has an answer an ignorant dunce like myself can understand.


I'm not pinning you to anything, and the ascent engines visible affect on the flag is a valid point to the horse we are talking about. It Merely points out the fact the exhaust is significant. No, I don't want the bible. I guess my attitude here comes from when I talk to people about this, they have been so brainwashed into believing the exhaust was a gentle cushion of air that had little affect on the soil. The affect of the thrust on the flag (3500lbs) is significant to demonstrating to common folk like myself exactly what is happening here. It isn't gentle summer breeze as they have been lead to believe. Your right, you didn't say the soil was unaffected. I merely feel it would have been more affected based on videos of 15, 16, and 17 during descent and landing.

You base your beliefs on data that is understandable to you, I base mine on data that is understandable to me. Pictures go along way with me and the guy from NASA said, "Tell them the proof is in the photos". A statement that resonated within my soul so here I am.

You know, it was rumored, rumored mind you, no fact to base this on, that Chris Craft used a vacuum chamber to dry out his home furniture after a flood. Too bad NASA won't free up any time today to demonstrate these facts but I guess whackos like me are few and far between and like the President, no need to debate if your ahead in the polls.



Always,

Uncle Jim

Well, the may be the same 'type' of model, but I would argue that the one Jay is using is much simpler than a weather forecast, and much less fowl-able.

__________________
Hwæt! We Gardena in geardagum,
þeodcyninga, þrym gefrunon,
hu ða æþelingas ellen fremedon.

(snipped)

I thought you were a kindler, gentler hoaxer, mr. unclejim...

Whoops! I think your horse got loose again.

__________________
"You keep using that word. I do not think it means what you think it means." Inigo Montoya

Jay, I know what kind of model you meant, they are used in weather forecasting every day.

Some are. That is not the only application of CFD, nor is it particularly representative of the strength or fidelity of CFD. We routinely build CFD models that very faithfully represent the actual measured effects.

We now have actaul data (allegedly) and no longer need the model.

I disagree. The numerical models and other things help us understand the observations in the photographs and videos.

I am having a hard time understanding why the soil is so unaffected....ie the probe soil displacement along with the little mound of soil built up on the inside of the pad that has been pointed out.

I agree you're having a hard time. That's the problem.

For example, why do you think the exhaust traveled flat across the ground? I explained what happens to a plume when it hits a flat surface. If you had internalized that explanation, you would realize that the bulk of the plume dispersal would have been above the footpad and therefore not very eligible to drastically affect a pile of dirt under the lip of the footpad.

You mentioned 2500 lbs of thrust at touchdown. I'd be willing to venture to say on 11 it was a little more.

I wouldn't. In order to maintain a constant descent rate (i.e., hover) the computer has to constantly reduce the throttle setting as fuel is consumed. The amount of thrust necessary to hold a descent rate is equivalent to the lunar weight of the spacecraft and its fuel. Fuel is the single biggest mass-contributing element to an Apollo spacecraft. Apollo 11 landed with practically dry tanks. That means it would have landed with the lowest hover thrust of any of the missions.

Either way, 2500 lbs is a significant blast.

Compared to ... ?

They were kicking up some serious dust when they landed.

Compared to ... ?

The picture anomaly I am still at odds with is the fact the soil from the probe has spilled over and on top of the print.

Why is this anomalous given the scenario I described?

I merely am questioning (same horse) how and why the dust you use as your evidence, appears to be undisturbed by the thrust of the LEM as it landed.

I provided an explanation. You simply expressed disbelief in it.

I just look at the dust displacement during landing from alleged actual videos.

Did you talk to any of the pilots? They'll tell you what they saw in three dimensions, that the grainy flat films don't show.

That horse is in the barn unless someone has an answer an ignorant dunce like myself can understand.

Whether you're an "ignorant dunce" or not is irrelevant. If that condition exists, it can be remedied -- but only with your cooperation.

Notwithstanding, it is not generally true that fully explicative answers are necessarily comprehensible to the layman. The explanation is the explanation; whether you understand it is up to you. If the explanation requires a detailed understanding of fluid dynamics, and you don't have that understanding, then any explanation we could offer would be either incomplete or incomprehensible to you.

...and the ascent engines visible affect on the flag is a valid point to the horse we are talking about.

No. It isn't.

It Merely points out the fact the exhaust is significant.

No. The APS is almost half again more powerful than the DPS at hover. It also ignites ten feet from the surface and the plume impinges on an irregular platform.

A nylon flag is affected by even the slightest breeze. Compacted cohesive regolith is comparatively unaffected. The Apollo 11 flag was blown over by the hot-fire test of the RCS. That's how easy it is to blow over one of those flags.

You cannot quantitatively compare the APS to the DPS. You cannot quantitatively compare a flag to a compacted regolith.

I guess my attitude here comes from when I talk to people about this, they have been so brainwashed into believing the exhaust was a gentle cushion of air that had little affect on the soil.

Most of the people I have heard argue this can cite fluid dynamics computations or first-order approximations of them that support their beliefs. Those who argue it was a tremendous blast offer only unquantified comparisons of dubious fidelity. Which would you consider more brainwashed?

The affect of the thrust on the flag (3500lbs) is significant to demonstrating to common folk like myself exactly what is happening here.

But it's not exactly what is happening in the descent. It just bears enough resemblance to it in order to appeal to the layman.

You base your beliefs on data that is understandable to you, I base mine on data that is understandable to me.

Sensible, but since my data and my understanding of it are the same that are used to engineer these mechanisms in the first place, and yours is admittedly based on your lay analysis, which of us is more likely to be closer to the truth?

Pictures go along way with me and the guy from NASA said, "Tell them the proof is in the photos". A statement that resonated within my soul so here I am.

Good for you. Now what are you willing to do in order to understand what you see in the photos? Welch didn't necessarily intend that the photos simply be looked at casually by laymen without consulting other materials. The proof may or may not be in the photographs. But if it is, extracting that proof is not necessarily a task for the casual investigator.

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

Someone might like to check my maths here (okay, the process is a bit dodgy, but I think the concept is sound)...

Consider the thrust plume as it blasts out of the combustion chamber, hits the surface of the Moon, and spreads out. This thrust will exert an amount of pressure on a point on the surface which is related to the distance that point is from the combustion chamber (I think).

In any case, some sort of inverse square rule would suggest that as the plume spreads, it'll exert steadily less pressure the further it is from the combustion chamber.

So how much pressure are we looking at when the plume has spread out to the foot pads?



The maximum diameter of the LM was 9.37 metres (from one footpad to the opposite footpad);

A circle with a diameter of 9.37 metres has a circumference of 29.4 metres;

Converting from Metric to Imperial, we get a circumference of 1158 inches;

The thrust from the DPS at touchdown was about 2500 pounds;


Divide thrust by circumference, and you get a pressure of a little over 2 pounds per lateral inch.



Now I remember Uncle Jim made a mention of breath exerting a pressure of 8 ounces. Well, I don't know how much pressure a person's breath actually exerts, but I think 8 ounces is about a quarter of 2 pounds. That's not so far off, is it?

If Apollo 11 was faked, how did NASA make everything on the Moon look like it did on the (supposedly) real later missions?

And if Apollo 11 was faked, how did NASA manage a more challenging mission as the first real landing? After all, each mission from Apollo 11 added something new, up until about Apollo 16:

Apollo 11: landing plus 1 EVA.

Apollo 12: pinpoint landing plus 2 EVAs.

Apollo 14: pinpoint landing in rough country, plus 2 EVAs, the MET, and an EVA up a hill.

Apollo 15: pinpoint landing, plus 3 extended length EVAs and the Rover.

Apollo 16: pinpoint landing in the highlands.

Which of these was the first landing on the Moon?

The engine did change; one difference that would have a noticeable impact on the dust levels is that the bells on the engines used for the last three landings were longer.

According to the The Apollo 15 Flight Journal

In fact, there was damage to the bell of at least one LM (Apollo 15) from the landing due to impact of the bell into the regolith. This was of significant concern to the missions because of the possibility of a pressure build up within the bell and a subsequent explosion that could damage the LM.

Any extrapolation from 15, 16, and 17 to the 11 landing will have to consider this. How can one do this without the use of Jay’s models?


Go Blue!

__________________
Living on Earth may be expensive, but it includes an annual free trip around the Sun.

Haven't seen the old derrick in a while. 'Course, I kind of quit caring after Bud Adams (don't let the door hit you in the a** on the way out) weaseled out of town...

Back on topic - unclejim, what would it take to convince you that A11-13 were not "fakes"? Just curious.

Just a couple of things.

First the thrust of a rocket engine is dependent upon two parameters. The flow out of the nozzle and the pressure force at the exit plane.

http://www.grc.nasa.gov/WWW/K-12/airplane/rockth.html

For the LM at landing, about half the thrust is the pressure force and half the force is due to the flow. So in reality the force on the lunar surface is around 1500 lbs. My over 2000 lbs car is in the parking lot right now and it is not creating any holes, ruts or whatever.

Second, the engine nozzle was about 54 inches in diameter or about 2300 square inches. Using the two numbers shows that the pressure is less than 1.0 psi.

>>I only used that statement because it so often comes from your side of the argument (not from you but other Hoax Busters) that the things that are not explainable are due to the "strange alien environment of the moon"<<

It's a valid point, but not presented that way. The moon environment is different from Earth, obviously, but there is nothing strange about it. However, quibbling over terminology aside, it remains true that the difference in the environment is a significant factor. One cannot always argue that something that behaves a certain way on Earth will behave the same way on the moon. As an example, take Bill Kaysing's comments about rocket tests in the Nevada desert producing huge clouds of red smoke. This, he says, coupled with the fact that no clouds of red smoke were seen on the LM footage, shows the landings were faked. He utterly fails to consider that a rocket tested in the Earth's atmosphere will certainly involve the gases present in the atmosphere in its combustion process, a situation obviously not applicable in the lunar environment, so the argument cannot stand.

On the other hand, light behaves the same way wherever you are, so in most arguments about shadow angles and the like, terrestrial examples are admissable in counter arguments.

But the soil is notunaffected. As I pointed out, there is evidence of significant streaking of the soil that is consistent with the effect of the descent engine as understand it, and I also pointed out that the displaced soil does seem to be affected in a similar way. All you are doing here is quibbling over quantity. And still I search in vain for the pile of soil on the inside of that footpad, or any other in the Apollo 11 record.

It isn't, for reasons already described. The two engines are not equivalent, and nor are the two things being affected by them.

It points to the fact that the ascent engine exhaust has a significant effect on a flag. It is not related in any way to the effect of the descent stage on the lunar regolith. You might as well ask why a kid on a tricycle bounces off a brick wall when a bloke on a motorcycle can ride straight through a plate glass window.

So the explanation of a man with detailed understanding of the physical processes involved is inadequate because you feel that things should have happened differently?

And it hasn't occurred to you that this might be because it's true, or because that's what all the evidence at hand leads them to conclude?

I look at the photos of the LM on the lunar surface, see the wide engine bell, see the streaked soil, and I conclude from the evidence available that the engine thrust at touchdown was sufficient to disturb the surface, but not a huge blast that dug out a crater or anything like that. Since the composition of the lunar regolith is not something I am overly familiar with, I don't have any basis on which to argue that it should have been more affected either. If I'm curious about how unaffected the soil should have been, I go and do a bit of research, and I find out things like the thrust at touchdown, the diameter of the engine bell, the likely effect that would have on something like the lunar regolith. Lo and behold, I conclude that the photo makes perfect sense in light of the facts I turned up.

You, on the other hand, are making an argument that requires knowledge of the LM, the engine, the lunar regolith and many other factors to substantiate it. You freely admit you do not have that knowledge, demostrate no inclination to go and educate yourself, and then you refuse to accept the arguments of individuals who have the relevant knowledge and are willing to pass it on. Not only that, but you throw in a random photo for no reason, and then produce other evidence that is not as related to the problem at hand as you seem to think, ignoring the comments that tell you why it isn't relevant. The visual effects observed in that photo have been explained sensibly to you, yet you are either unable or unwilling to accept them.

__________________
"The very powerful and the very stupid have one thing in common: They don't alter their views to fit the facts, they alter the facts to fit their views." The Doctor, Doctor Who: The Face of Evil.

First the thrust of a rocket engine is dependent upon two parameters. The flow out of the nozzle and the pressure force at the exit plane.

For most launch vehicles the pressure thrust is zero at some altitude. American rockets are traditionally tuned for optimum expansion (i.e., exit plane pressure equal to ambient pressure) at sea level while Russian rockets are traditionally tuned for optimum expansion at about two minutes into the initial boost. N.B. this is for launch vehicles that are designed to operate within an atmosphere and thus to adapt to changing ambient pressures.

For the LM at landing, about half the thrust is the pressure force and half the force is due to the flow.

That's actually higher than I would have estimated. I would have put it around 10-20 percent of total thrust.

Optimum expansion is not practically achievable for a vacuum. You can never have a nozzle in which the average static exit plane pressure is zero. But because the nozzle doesn't have to accommodate changes in atmospheric pressure as it climbs, it can be optimized as far as possible. Oops, I think I see my mistake: I haven't factored in the throttle. At 25% throttle you would have much less than optimal expansion.

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

I'm sorry I can't respond to all of you, the library guard only allows us so much time.

You know, I took on a grievance last year and brought it to a meeting where we were outnumbered 128 -2. Well, here I Am again and my butt is just about as sore. The sad thing was, is that in that case the grievant and myself were correct.

Put all of your thrust ratings, nozzle theories, and degrees away boys. I've proven what I need to prove and no, it wasn't that Apollo 11 didn't land on the moon.

If you look at my opening statements I spoke of how a person who opposes anything is likely to get trampled in a discussion on this site. It is sad some of you don't see the moon landing for what they are when it comes to the Hoax discussion. It is the D.B. Cooper of Space. A fun topic . If you have the evidence on your side, why are you so defensive?

The horse I leave on is the one I rode in on. Actually I didn't ride a horse in but Jay convinced everyone of that so I'll go with it. I thought I made it obvious in my opening statement I was walking in, in a humble manor into your home. Not quite, but almost instantly the condescending nature of a few of the board masters presented themselves like a car salesman on a used car sales lot.


The picture is just that, a photo. For what Jay claims to be true, not only would the triangular print be smeared, but the displaced soil from the probes next to it would be flattened as well. I see that, an LA homicide detective see's that. We simply disagree fellas, it's not the end of the world. I didn't come here to change your mind on this fellas, I knew that would be impossible. I came here to see if anyone could adequately answer some of the question I have, and no, they just weren't about this one photo.

Now Jay kept accusing me of changing horses. Well no, not at all, not on this subject. Jay presented the soil around the pad as evidence and he has to expect that evidence to be required to be validated, not taken just at his word, no matter who he is. And while he claimed he never said the soil was unaffected by the blast, he implied that.

I believe Jay wrote:

There is nothing in the fluid dynamics model of the LM exhaust plume that stipulates significant direct or indirect loading at the site of the footpads. You're simply handwaving here.

And then later Jay wrote:

You're the one saying it's unaffected. I never did. Why do you keep trying to pin your assumptions on me?
God Jay, you crack me up. It looks like you the one doing the hand waiving here.

Why are you guys hiding in your own protective little world when you have an unbeatable case? (not necessarily conceding Jay, just saying based on current evidence, your side is unbeatable [-X ). Go take a look at other post on this site under this subject. You track out like scavengers, find someones claim, and then drag it back to your den in secret to ravage it with your comrades. You never confront anyone with your knowledge on their turf or do you?

I dated a girl once who had a God given talent (yeah I wish). She'd say her piece, listen to the response, maybe argue some more, listen some more and walk away when it was over. I said to her once, "Man, you missed a great shot, you could have pointed out....." She just responded, "My mother taught me at a young age that most people have to have the last word as they find power in that, so I let them have it."
So gentlemen, say what you have to say, I'll read it all. I'm going to go back and try to reread all of this as it was a bit overwhelming at times. I honestly have enjoyed it.

By the way, remember the meeting and grievance that the grievant and I were outnumbered 128 to 2. Although we received a butt whippen in public, the behavior in the scheduling process we brought to light ceased almost immediately.

Always,
Uncle Jim
One last quote for you on this subject
"Why Did God Create Alcohol? So us Irish would never rule the world."

Put all of your thrust ratings, nozzle theories, and degrees away boys. I've proven what I need to prove and no, it wasn't that Apollo 11 didn't land on the moon.

Ah, one of those wolves in sheep's clothing. You come here silently intending to determine that we're all dogmatic, concrete-headed buffoons who take things too seriously, and so you manage to wrangle a discussion that appears to you to have proved exactly that point. I said it before and I'll say it again: your methods are intended to convince people of a certain thing, not to determine whether that certain thing is the truth or not. This includes the notion of what our motives may be. You have exhibited no behavior to date that violates that characterization.

You would make a fine lawyer, but a very poor investigator.

If you look at my opening statements I spoke of how a person who opposes anything is likely to get trampled in a discussion on this site.

Of course. That's exactly the opening scene in the rhetorical script that you're acting out, which I see about four or five times a year in the various venues where I argue. You start out by saying, "I know you guys will beat me up for this." That predisposes an audience to attribute to our supposed hard-headedness and argumentativeness, any opposition we might offer. Then you lay out a case to which you know we will object. And you keep hitting on it, keep bringing out other evidence, in order to prolong the objection. The exact reasons for our objection are immaterial, because your plan all along is simply to elicit the objection. Once the objection is on the table you can invoke your a priori presumption of antecedent and attach it to the consequent you knew would be produced.

But of course in the real world -- not the isolated world of litigation -- an objection can come from many sources, not just the one you identify. The objection in this case came on the basis of quite a lot of applicable fact. You asked a question; we attempted to answer.

If you have the evidence on your side, why are you so defensive?

It takes two to tango; you deployed several arguments intended to support the same conclusion. The sustained refutation is in response to a sustained attack.

I thought I made it obvious in my opening statement I was walking in, in a humble manor into your home. Not quite, but almost instantly the condescending nature of a few of the board masters presented themselves like a car salesman on a used car sales lot.

Hogwash.

Astronot's contribution began with, "You’ve come to the right board, we don't treat posters that have questions rudely." There was even banter about sports and hobbies.

My first response was a brief summary of a determination I had made on the feature in question, and an outline of the scenario leading to it and a reference to the sources I had used as data. I made a followup to another poster who questioned me on some aspects of my findings. Both responses were factual and dispassionate.

The first time you mentioned me by name was to say

You simply dismissed my analysis by saying there were no "skid marks" (there are) and immediately suggested that my conclusion was based on some sort of preconceived opinion. Now that your ulterior motive is a matter of admission, I can see why you were so anxious to start down the path of personal arguments.

You continued, "(Jay, don't quit your singing job)". How can that be interpreted except as a personal attack?

Let's not bandy further: the ad hominem attacks started right there, with you, despite "olive branches" having been extended by me and by others. And I'm not the only one who feels this way. After I expressed my resentment of your approach, R.A.F. responded, "My thoughts about this, if posted, would certainly get me banned from here."

You came here with the intent to provoke a fight in which you would certainly get beat up, so that you could run home complaining about the bullies. Only we didn't bite; so you had to throw the first punch.

For what Jay claims to be true, not only would the triangular print be smeared

No. The bottom of the footpad is cupped so that it will ostensibly ride up on top of regolith rather than digging in. It is also covered with loosely-wadded insulation material (aluminized Mylar and H-film). The footpad will rotate in two axes on its "ankle" in response to underlying terrain. The insulation material will crush and deform in response to a load. Both of these will alter the profile of the portion of the footpad that is in contact with the regolith as the load varies.

I have seen exactly this type of compressive skidding on snow, which has many of the same mechanical properties as lunar dust (albeit for completely different reasons). In fact, if I had any inkling you were genuinely interested, and I had the ability to present it graphically, I could show you in step-by-step detail how one large crease in the insulation could be flatted into two creases by progressively heavier loads and produce exactly the triangular pattern of furrows seen in the compressed area near the footpad. You're dismissing the scenario simply because it doesn't jive with your simplistic impression of what a skid "must" look like.

but the displaced soil from the probes next to it would be flattened as well.

Only if the displacement occured before the flattening. As I explained in great detail, the displacement aft obviously occurred after the flattening and I proposed a scenario -- supported by multiple sources of data -- to explain just how that can have happened. The trench, in addition to being longer than the probe, is also wider than the probe. The regolith is displaced only on the rearward side of the trench, and the probe lies in the rearward portion of the trench. This absolutely telltale evidence that the probe was pushed backwards after having been embedded in the soil along most of its length.

The probe furrow is cut through compressed regolith because with the probe bent the way it is, it will continue to drag through it after the footpad has compressed it. There is evidence of compression on either side of the furrow.

I see that...

But you aren't an expert.

...an LA homicide detective see's that.

Anonymous authority. What makes him an expert on the Apollo lunar module? I am a recognized expert, and I have training in soil mechanics. Does your detective friend?

Further, I clearly refuted his rationale for dismissing the skid using nothing but dispassionate fact. You won't allow me to question him directly, and there's no evidence you transmitted my refutation back to him so that he could revise his opinion, if necessary. Once I pointed out that the "buckling" theory was not supported by the data, you dropped it altogether and moved on to something else.

I came here to see if anyone could adequately answer some of the question I have...

You came here expecting opposition to your questions. You got it. Now you seem to be complaining because you got what you expected.

You came here believing that your "underdog" conclusion had a very slim chance of being true. Now you seem to be complaining because that's apparently the outcome.

When you were presented with well-reasoned, factually-based, comprehensive answers using multiple sources of data, your response was not very consistent with someone who just wanted an explanation for an observation. People looking to be enlightened because they lack understanding generally don't fight that enlightenment tooth and nail when it's offered. From the very beginning you took up an argumentative position contrary to everything that was proposed. You cited anonymous testimony to confirm what you already believed. You sidestepped or simply expressed disbelief in all that was said. You ignored the items of data that directly refuted your assertions.

It's far too late for you to claim complete to be innocently asking questions.

Jay presented the soil around the pad as evidence and he has to expect that evidence to be required to be validated, not taken just at his word, no matter who he is.

I pointed out that there was a buildup of regolith which you and your detective friend had both apparently missed. You acknowledge that it was there and immediately launched into a secondary argument about why it shouldn't have been there. It took a few rounds of discussion before you were made to understand that it was intended to show, along with other bits of evidence, that the footpad indeed skidded.

You still have not dealt with the totality of evidence that universally points to the skid conclusion. You have taken a few potshots at pieces of it. You have followed a few related tangents. But you still have not explained how so much independent evidence can point so strongly to one single conclusion, and yet still be wrong.

And while he claimed he never said the soil was unaffected by the blast, he implied that.

I believe Jay wrote:

There is nothing in the fluid dynamics model of the LM exhaust plume that stipulates significant direct or indirect loading at the site of the footpads. You're simply handwaving here.

Yes, I said that. I can see where you might have been confused by that, and it relates to a part of the reconstruction that I didn't explicitly state. Sorry for misleading you like that, but let me go back and fill in a few gaps.

Let's hypothetically put the LM five feet or so above the lunar surface, hovering, and not moving forward, backward, left, or right. Where with the plume impact? Mostly on a spot directly beneath the nozzle, expectedly. You get the most velocity right in the center of the nozzle, so right under the thrust axis will be the strongest impact. As you move away from that axis, the downward loading decreases gradually until you get to the boundary of the supersonic portion of the plume. The vertical surface loading then falls off dramatically through the subsonic plume portion -- most of which disperses before striking the ground. Portions of it are even striking the bottom of the LM because they curl up around the lip of the nozzle. So if you go out to the diameter of the footpads, several meters from the thrust axis, there is no downward force at all.

So much for primary effects. But what happens to the plume as it hits the ground? It disperses, obviously, but not in a hemispherical pattern. And not in the pretty billows of smoke you see in earth launches. It goes out radially from the point of impact. As seen from above it would make a perfect circle of expanding exhaust products. But as seen from the side -- if the entire plume were made magically visible (as is done in our Fluent models) -- it would not be a hemisphere centered at the point of impact. In fact it would be a low, flat disk of material, with most of the gas departing the surface along an elevation angle of but a few degrees, and at fairly high velocity.

Thus, near the plume impact area you would expect the mostly horizontally moving gas to "scour" the surface, just as you hose the dirt off your sidewalk. But the farther outward you go, the higher above the surface is the densest portion of the reflected plume, since it's climbing at a shallower angle. It's still moving very fast, but it's decreasingly in contact with the surface and decreasingly able to scour it significantly.

The density of the exhaust plume is also decreasing at a rate proportional to the radius. This is the basic law of radial expansion. Plus, you have kinetic-molecular expansion into the vacuum. The plume, after striking the lunar surface, disperses rapidly. This does not preclude the visible dust seen in the 16mm films. After conversations with the pilots, I'm told the film overrepresents the amount of dust actually displaced. It is often assumed there is an opaque sheet of dust, when in fact the dust sheet was usually transparent.

Okay, so that's the general idea. The behavior of the plume simply doesn't lead us to expect a lot of scour near the footpads.

But what about the scour that is observed near the footpad in question? That's a good question.

As stated in my reconstruction, the LM was moving forward and to the left prior to touchdown. This means the bulk of the plume would have swept the right rear quadrant of regolith some seconds prior to touchdown. The streaking you see is the effect of the full brunt of the exhaust as it passed over that area, not the supposedly far-reaching effect of the exhaust as it fired from where it came to rest. This is amply evidenced by the total lack of streaking in any of the other quadrants.

And then later Jay wrote:

You're the one saying it's unaffected. I never did. Why do you keep trying to pin your assumptions on me?
God Jay, you crack me up. It looks like you the one doing the hand waiving here.

That statement was intended specifically to discuss the inboard regolith buildup. You imply that such a buildup should have been blown away by the exhaust. Its very presence in its current form seems suspicious to you.

Now I will admit here to having conducted a little rhetorical manuevering. I apologize if having done so has offended you or misled you.

Nothwithstanding the results of plume impingement models, I can't verify that the regolith buildup is, in fact, untouched. Nor can I verify that it has been eroded. There simply is no basis for making any judgement on that point. If it was eroded, it was eroded. If it went untouched, it went untouched. You seemed to want to polarize the issue: that if it wasn't totally obliterated then it must have been "untouched". My disavowal of the "untouched" hypothesis was not so much a retraction of my previous statements as it was an attempt to force the issue of suspension of judgment.

In a litigation setting, one outcome is usually presumed and the opposition is required to make a case refuting it. In criminal proceedings, innocence is presumed and thus a prosecutor carries the burden of proof. If he fails to satisfy it, the accused is found "not guilty". He is not found "innocent". To determine innocence one must make a case for innocence. The defense, instead, has merely to rebut a case for guilt. The two are most certainly not the same thing.

In an investigational setting, there are three outcomes to each hypothesis: "proved", "disproved", and "inconclusive". Litigation merely decides what to do in the inconclusive case. But in our mode we can let it stand as inconclusive. Litigation must have an outcome. Investigation need not.

That was the point I was hoping to make.

You never confront anyone with your knowledge on their turf or do you?

All the time. Most of the people with whom I associate here have "extracurricular" opportunities to share these ideas. Most simply don't have the time to do it as much as I do.

I honestly have enjoyed it.

Would it help if I took you less seriously from now on?

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base