Bart's 5:1 Russian superiority claim

[margamatix]

jayutah said:

Uh, your signature used to be a direct, attributed quote from Bart Sibrel disputing the validity of the LM engineering.

I change my signature every week or so. That was one, ephemeral, signature.

Having said that, I completely agree with Sibrel on the ludicrous unsuitability of this craft to land on the moon and then take off again, let alone rise through 70-odd miles into moon orbit.




Run it by me again. On descent, the LM cut out its engine six feet above the moon's surface.

It weighed 11 tons



So it fell to the moon's surface with the same force as an object weighing nearly two tons would do if it fell six feet onto the Earth's surface, without coming to any harm.

I don't think so.

[nomuse]

I love the locution used here. "I happen to agree with Sibrel...."

Margamatix, with the technical, engineering, and scientific background you have demonstrated so far, it becomes extremely difficult to believe you independently came up with the majority of your arguments. The idea that your arguments (say, about melting film, see thread) come from a source external to you is bolstered by your unwillingness or inability to ever move beyond your opening argument.

This is key to our entire discussion. If I disagree with Jay (I wouldn't dare on Apollo, but I'd challenge him on live sound...) we both pull out references, discuss with fellow professionals, post links, expand our arguments, answer each other's questions, attack each others answers, etc. The conversation evolves because we both have a willingness to develop our arguments and to do the research needed.

In almost every discussion I have witnessed on this board, your discussions start with a "question" I recognize from other hoax sites. And they end with the same statement. Since you refuse to do any independent work expanding on the question or the responce, making yourself simply a condoit for the claims of Bart Sibrel or others, it is a legitimate tactic on our part to ask WHY you take this material so on trust, and refuse to explore it.

Such as this thread, where we pointed our Sibrel did either unbelievably slipshod research, or lied outright, on one of his claims. Sure, there are other claims. But look at it this way; when a doctor slips up so badly, removing the wrong limb or performing a needless surgery for the money, do we let her continue operating? Bart has built himself up as an expert, in depth and detail, on the Apollo program. His claims come out of that purpoted expertise. It is essential to the counter-argument to discover that he lacks either expertise in the subject, or honesty in his reportage.

[nomuse]

margamatix said:

Having said that, I completely agree with Sibrel on the ludicrous unsuitability of this craft to land on the moon and then take off again, let alone rise through 70-odd miles into moon orbit.

Run it by me again. On descent, the LM cut out its engine six feet above the moon's surface.

It weighed 11 tons

So it fell to the moon's surface with the same force as an object weighing nearly two tons would do if it fell six feet onto the Earth's surface, without coming to any harm.

I don't think so.

You do understand that gravity is an ACCELERATION, don't you? The LM continues to mass exactly what it did on Earth. It falls, however, much slower.

And if you don't believe an eleven-ton vehicle can fall six feet without damage, you haven't been to a monster truck show. I know. Facetious of me. The point being; why _couldn't_ the LM be designed to absorb the impact of what under lunar gravity is the equivalent of a fall of a couple of feet? Do you think those big spindly legs were just for show?

[Bob B.]

margamatix said:

Having said that, I completely agree with Sibrel on the ludicrous unsuitability of this craft to land on the moon and then take off again, let alone rise through 70-odd miles into moon orbit.

And you base this opinion on what? Your gut feeling? There are people here with actual engineering experience in the design of spacecraft that have no problem with the design of the LM. I too am engineer, I have studied the LM, and I have no reservations about its stability or its ability to rise to the prescribed altitude. I know that both you and Bart Sibrel are wrong based upon my applicable education, training and experience.

margamatix said:

Run it by me again. On descent, the LM cut out its engine six feet above the moon's surface.

It weighed 11 tons

No, it weighed about 2,700 pounds.

margamatix said:

So it fell to the moon's surface with the same force as an object weighing nearly two tons would do if it fell six feet onto the Earth's surface, without coming to any harm.

Your figures are incorrect; nonetheless, the LM was designed to absorb the anticipated impact. The legs of the LM had shock absorbers for this very reason. Were you aware of the shock absorbers or is this just one more thing you were oblivious of?

margamatix said:

I don't think so.

I really doesn't matter what you think because you are not qualified to offer an expert opinion regarding the LM's design.

[JayUtah]

I change my signature every week or so. That was one, ephemeral, signature.

Irrelevant. You asked for other examples of where you had refered to Sibrel. I gave you one. Now please stop making irrelevant requests and answer the question of Sibrel's trustworthiness regarding the 5-1 superiority matter.

Having said that, I completely agree with Sibrel on the ludicrous unsuitability of this craft to land on the moon and then take off again...

Irrelevant. You're being asked instead about the supposed 5-1 superiority that has been thoroughly, conclusively debunked.

Please answer that question.

[margamatix]

jayutah said:

Irrelevant. You're being asked instead about the supposed 5-1 superiority that has been thoroughly, conclusively debunked.

Please answer that question.

Once again, I didn't start that thread, I hadn't contributed to that thread, and at the time I was already under fire for commenting on too many aspects of the Apollo fakery at once.

I declined to comment on the thread because of this, and had continued to do so.


Although- unlike you- I do not base the success of my posts on my ability to cut n' paste the longest message possible, I will make an exception here, under extreme provocation.....



"The Soviets had a five-to-one superiority to the U.S. in manned hours in space. They were first in achieving the following seven important milestones:

• First manmade satellite in earth orbit…
• First man in space…
• First man to orbit the earth…
• First woman in space…
• The first crew of three astronauts onboard one spacecraft…
• The first space walk…
• The first of two orbiting space craft rendezvousing… "



So of course, Bart Sibrel IS wrong. He should have said a 7-1 superiority.



We didn't go there Jay. It was all faked in Nevada. Get over it.

[ottawan]

Just a point of order.

You're 7th "milestone" is in error. The craft did not "rendezvous" as they were not capable of altering their orbits.

They were launched a day apart into the same orbit and came no closer together than 3.1 miles.

That was Vostok 3 with Andrian Nikolayev and Vostok 4 with Pavel Popovich.

[Bob B.]

margamatix said:

The Soviets had a five-to-one superiority to the U.S. in manned hours in space. They were first in achieving the following seven important milestones:

• First manmade satellite in earth orbit…
• First man in space…
• First man to orbit the earth…
• First woman in space…
• The first crew of three astronauts onboard one spacecraft…
• The first space walk…
• The first of two orbiting space craft rendezvousing…

So of course, Bart Sibrel IS wrong. He should have said a 7-1 superiority.

The 5-to-1 superiorty was in regard to "manned hours in space", not important space milestones. You would have know this had you read every one of our posts as you swore to God you do.

Furthermore, Bart Sibrel's list is incorrect in some places and misleading in others. For instance, the first man in space and the first man to orbit the earth is one in the same, thus Sibrel is just padding the list. Also the first woman in space isn't exactly an important milestone. Finally, the Soviets did not perform the first rendezvous in space, this was done by the Americans during the joint Gemini 6/7 mission. The Soviets just launched two spacecraft on trajectories that caused them to fly by each other at a close distance. Neither craft had the capability to change its trajectory and maneuver to a true rendezvous.

edit spelling

[Bob B.]

margamatix said:

jayutah said:

Irrelevant. You're being asked instead about the supposed 5-1 superiority that has been thoroughly, conclusively debunked.

Please answer that question.

Once again, I didn't start that thread, I hadn't contributed to that thread, and at the time I was already under fire for commenting on too many aspects of the Apollo fakery at once.

I declined to comment on the thread because of this, and had continued to do so.

Oh by the way, your further evasion is duly noted.


edit spelling - darn, can I ever get it right the first time!

[sts60]

Although- unlike you- I do not base the success of my posts on my ability to cut n' paste the longest message possible, I will make an exception here, under extreme provocation.....

You rarely fail to take strenuous objection to any perceived slight, and yet you make such a statement?

Don't tell me it's between you and him. You made a snide comment, but more importantly, it's clearly wrong. I've seen JayUtah post in a number of places, and I have yet to see him "cut and paste" any substantial material of his own into a post. Sometimes, I wonder at his patience in posting lengthy newly-composed explanations to people who often reject them out of hand.

But a lot of his posts are lengthy because he makes detailed explanations. If you can't be bothered to read them, fine, but don't decry someone for taking sufficient time to analyze your claims carefully.

So of course, Bart Sibrel IS wrong. He should have said a 7-1 superiority.

Well, your post was quite pithy, so it had the virtue of being a quick read. It also showed you weren't paying attention to the central point of this thread: the fact that Sibrel claimed the USSR had a five-to-one advantage in spaceflight hours when Apollo flights started (Sibrel himself said this claim included Gemini), and that this claim is utterly, spectacularly, wrong. As was clearly detailed by Jason Thompson and Bob B. on the first page of this thread. Didn't you read these posts?

We didn't go there Jay. It was all faked in Nevada. Get over it.

Tell you what. I don't speak for Jay, but show me something that demonstrates you have any understanding of spaceflight, or space environments, or the most fundamental aspects of heat transfer, and I will consider "getting over it".

[JayUtah]

I declined to comment on the thread because of this, and had continued to do so.

Irrelevant. You claim to have read every post. You're simply being asked to comment upon the posts you say you've read. If you haven't read them, you're being asked now to read them and comment on them.

So of course, Bart Sibrel IS wrong. He should have said a 7-1 superiority.

That is not his claim. He said the Soviets had a 5-1 advantage in hours in space. That -- not qualitative milestones -- is what you're being asked to comment upon.

Now please answer the question. For all the protestations you've made about how inappropriate the question is, and all the side-trips you've taken, you could have answered the question a dozen times over by now.

[JayUtah]

We didn't go there Jay. It was all faked in Nevada. Get over it.

I understand space travel and you don't. Get over it.

[sts60]

I change my signature every week or so. That was one, ephemeral, signature.

Does that you mean you no longer believe the claim you used in your signature? Or that you didn't agree with it in the first place? Or you did agree with it, but you don't think we should challenge it?

Having said that, I completely agree with Sibrel on the ludicrous unsuitability of this craft to land on the moon and then take off again, let alone rise through 70-odd miles into moon orbit.

We've shown you facts and figures. What problem, exactly, do you have with the LM?

And since Sibrel has been shown to be incompetent in many of his technical claims, why should his opinion matter?

Run it by me again. On descent, the LM cut out its engine six feet above the moon's surface.

It weighed 11 tons

So it fell to the moon's surface with the same force as an object weighing nearly two tons would do if it fell six feet onto the Earth's surface, without coming to any harm.

I don't think so.

The LM mass at landing was the sum of:

dry mass of the ascent stage: 2180 kg
ascent stage propellant: 2639 kg
descent stage dry mass: 2034 kg
descent stage propellant: 8212 initial, minus that consumed during descent: let's say about 1000 kg left - most of it was burned during descent.

That's a total of roughly 7900 kg, or 17400 lbs, or 8.7 tons. Not 11 tons. So you're wrong there.

If the engine was cut off at 6 ft above the surface, we can find out how long it would have taken to free-fall the remaining distance:
s=(1/2)a t^2, where a = (32 ft/sec^2)/6 = 5.3 ft/sec^2

t^2 = 2 / (5.3 ft/sec^2) * 6 ft = 2.25 sec^2, or t = 1.5 sec.

The speed at touchdown would then be v = a t
= 5.3 ft/sec^2 * 1.5 sec = 8 ft/sec or 2.4 m/sec.

The LM landing gear consisted of four legs, each comprising a primary strut which took up most of the load and secondary struts which took up more lateral loads. Each struct had a built-in shock absorber made up of a crushable aluminum honeycomb - pretty standard engineering practice. The primary structs would compress up to 10" under 4500 lbf of load, and up to 32" under 9500 lbf of compressive load. (Source: LM Structures Handout, LSG-770-154-10, NASA/MSC, May 1969.)

Let's say the LM took nine vertical inches (3/4 foot) to come to a stop as it compressed the shock-absorbing struts. The average deceleration d is found by combining the equations
s = 3/4 ft = 1/2 d t^2 and delta v = 8 ft/sec = d t (I'm ignoring signs for deceleration vs. acceleration here)

So, t = (8 ft/sec)/a, and substituting

3/4 ft = 1/2 d (64 ft/sec / d)^2

So d = 43 ft/sec^2 = 13 m/sec^2 or about 4/3 G - not very rough!

The force applied to the landing gear is then F = md
= 7900 kg * 13 m/sec^2 = 103,500 kg-m/sec^2
or 25.9 kN per leg. One newton = 0.225 lb,

so each landing leg in this scenario was subjected to 5800 lbs on landing - well under the load the struts were designed to take in their compressive range.

Of course, this is not exact - the contact probes were 67" (5' 7") long, not quite 6'; the engine didn't really cut off 6 feet off the ground as margamatix claims; and there could have been a little downward velocity, although not much.

Indeed, according to the the Apollo Lunar Surface Journal, the A11 touchdown was very gentle; others were somewhat bumpier. There was also an engineer's comment that an engine cutoff above 10' would have exceeded the LM landing gear design rating - which, of course, is why it was designed to be shut down once the contact light came on.

Also: looks like the average Apollo landing had about one thousand pounds of fuel left in the descent stage. So I think I was rather conservative in my initial estimate of mass anyway.

So we can dispense with margamatix's claim that the LM should have been harmed by the descent engine being shut off (around) six feet above the surface.

[rocketdad]

Thank you, sts60, for the informative answer.

That's why I keep coming back here, for the "mathemagic." I'm truly interested and happy to learn. I'm a bit of a putz with the numbers myself, so I'm glad to have people like you who are willing to do the "heavy lifting" for us.

From this, I can extrapolate that dr. von Braun's 50-person lander design would need much better shock absorbers.

[margamatix]

jayutah said:

That is not his claim. He said the Soviets had a 5-1 advantage in hours in space.

Did he? Well then I'll have to stand corrected. Like I have said, about a dozen times now, I haven't read Bart Sibrel's claim and so am not qualified to comment on it.

Hope this helps.