nothing on the density and velocity of the descent engine exhaust gas in the nozzle , and it didn't take me 6 months to see this , but rather 9 - 10 minutes , sure they are proud of their throttable engine, because they 'brag' about how throttable he is in just every single pages of the engine section , but its just an engine that never landed on the moon and that is certain of course , but i wonder how many months it will takes you to understand that.



or 10 minutes ...



blindly relying on documents isn't the best thing you can do when the landing as been videotaped , and the whole landing scene taken in photos , so i rely on the photos and video as well , and in the photos you can see the engine nozzle (and not the engine top) , at less than 40 centimeters of that dusty ground , also you can see a constant blowing-away of dusty surface as long as the engine isn't turned off , the ~15% throttle is the minimum , that don't mean its the percentage at landing , and to finish , you clearly didn't looked the apollo landing videos at all (or didn't see them for a while at least) , because if you did , you would clearly see that in many of them , the engine isn't stopped even after landing , and stay on for 3 to 6 seconds on some vids , (apollo 14 ones in particular).



as they said maybe , too bad that once again , the video didn't tell us the same story , this constant blowing-away of dusty surface never stop and never loss intensity as long as the engine is ON , they clearly didn't landed on a dust-free surface , and we should have seen a crater under that 40 centimeters of the ground rocket engine nozzle.

...

LLL,

I've had time to sit down and think about your dynamic pressure problem. I've concluded that dynamic pressure is already factored in to how the thrust value is calculated (same equation for dynamic pressure) (F = m° Ve where m° is mass flow rate of propellants and Ve is exhaust velocity). You then need to convert this to unit pressure, which would calculate the pressure exerted by an ideal plume. To do this you divide the total dynamic fluid pressure by the exit area of the DPS nozzle, and as I mentioned before this is using the standard P = F/A.

I hope this answers your question.

http://www.nasa.gov/centers/johnson/about/.../jsc40_pg8.html

Click to view attachment
Apollo Mission Evaluation Plan (NASA-TM-X-70019) Page 3
http://ntrs.nasa.gov/archive/nasa/casi.ntr..._1974074531.pdf

MID was clearly referring to your claim that NASA "as always they lost every single technical specification of the historical masterpiece that allegedly landed man on the moon , how strange is this ?"

The 800+ page document chock-ful of technical information about the LMs operation and it's various sub-system says otherwise - and this is just one document.

I'm sorry you didn't find the data you're looking for. Perhaps that's because the information is irrelevant to the operation of the LM by its pilot (in the same way that the pilot of a 747 doesn't need to know the density and velocity of the exhaust gas from the turbine engine in order to be able to fly the plane).

The section of the document pertaining to the descent engine I found to be very dry and technical, didn't come across as boasting at all.



You did very well to read that 800+ page document in ten minutes! I make that 80 pages a minute. More than one a second! You're certainly a faster reader than me.

LLL, I'm getting the vibe here that you seriously have it in for NASA and the Apollo programme in particular, maybe that is clouding your judgement somewhat in analysing evidence objectively?



I agree, the engine in the Apollo 14 landing sequence looks to me like it was turned off after touchdown. Here's what Shephard had to say in the 1971 technical debrief:-

"For touchdown, we had the habit of waiting (in training) about 2 seconds after the contact light came on before shutting the engine down. From the looks of things, we actually were on the ground and stopped before the engine shut off. It must have been a pretty light touchdown."



Who said the lunar surace was dust-free?

There are plenty of images showing the area beneath the LM on magazine 66, check out the hi-res versions on the ALSJ.

For example, look at AS14-66-9261 . I've highlighted some areas below (but look at the hi-res version linked). The red zone shows very clear evidence of dust being scoured (this is the direction that the LM approached from). The green zone shows some striation in the dust - evidence of the dust plume radiating out from under the LM? The blue zone, underneath the exhaust bell, appears to me to be slightly discoloured - possibly evidence that there was some kind of heating effect?

http://www.hq.nasa.gov/alsj/a14/AS14-66-9261HR.jpg

it doesn't , we don't know the density and velocity , that's why i said they've lost their technical specification , because these kind of datas are of course known before landing on the moon , F= m° Ve + (pe - p0) Ae , and we only know the Ae .

I bet there are things like rocket or missile data that is heck to get from any government sources, by way of general inquiry.

Just a thought.

LLL, Click for Big

Just "skipping through" the LM manual (I cannot claim to have "read" it), I found a couple of interesting numbers for the DPS.

Fuel filter rated flow=13.3 lb/sec
Oxidizer filter rated flow=21.2 lb/sec

It's safe to assume the corresponding mass flows were something less than these figures, which I assume correspond to a full throttle setting.

BTW, LLL, was this LM manual all "pretend", just all made up with random technical jargon to "look good" for the casual reader?

Evidence? Prove this statement, please.

And if your answer to this question is yes then please explain why it is only hoax believers that caan see this and not the thousands upon thousabds of trained and educted enginneers in the world.

So it seems the LLL's true agenda here has made itself known:

- fabricate his own or repeat other's ludicrous claims
- ignore any and all evidence that counters those claims
- refuse to do any real investigation, reading or research of his own, except for searching YouTube
- demand explanations for things he has misunderstood
- ignore those answers since they don't validate his own faulty ideas
- when definitively proven wrong about something, either ignore it or grudgingly accept it and then mope about it for several pages after

My prediction of being relegated to background noise seems to have been proven correct, at least for me.


Cz

Yeah. Copying an equation off another website, without even working it, doesn't impress me.

Brilliant, LLL.
I appreciate the astuteness of your reasoning here.



Of course, you read this thing in 10 minutes. I should've guessed.






LLL, you really must relax on the preconcieved notions which blind you to what was said.
Of course the engine nozzle was sitting a mere foot and a half off the ground when the LM was on the surface. Hell, it's nominal ground clearance was about 10 inches!

What I said was that the engine was cut off between 6 and 8 feet above the ground...normally.

And yes, 10 to 15 % thrust was the value at landing. You can look up the various Apollo Experience Reports for data on throttle setting during the final phases of lunar landings. Much more than the values I gave you would result in the vehicle ascending (the fuel was mostly burned off by that phase of the flight profile...and of course you understand, weight reduction requires less and less thrust to keep one aloft, right?

LLL, I was right there for all Apollo landings as trhey hapenned. I saw all the films of them as well... The only landings that may have had there engine running right until, or very shortly before touchdown was Apollo 11's, and Apollo 14's. Everyone else attempted to shut down upon contact light, although Al Shepard though he had landed with very low velocity and may have touched with the engine still running.

Engine cut off NEVER came 3 to 6 seconds after touchdown. Almost all of them came before touchdown. And on 11 and 14, it came immediately upon touchdown.
No one ran the engine after touchdown. The thermal effect could've damaged the vehicle. I don't think you actually know what you're seeing in those DAC films...





And again, some substantiation for this theoretical construct might be helpful.
The fact that the dust continually blew away from the area of impingement upon it clearly indicates that the DPS never got all of the dust off the surface beneath the LM...and so, couldn't have even come close to boring a hole in the hard substrate!

And of course, the photography taken of each of the LMs rather confirms this fact....

Ah, Mr. B., you have indeed been perceptive.

LLL reads that document in 10 minutes...which is probably why he never saw the figures you show above.
You're correct, those were a bit higher than 100 % flow (and would be a bit more than the requirement for a full throttle setting).
It also happens to be at about the right mixture ratio.

Thus, the fuel flow could be estimated for full throttle...and thus, if it were actually necessary to convince him of the efficacy of the LM DPS engine, calculate the fuel flow rate, which would give him a variable that could be used to calculate exhuat gas velocity....but then again, what's it matter?


It's all falsified data, of course, and the LM couldn't have landed on the Moon.


He's already come to that preconceived conclusion without any research whatsoever...

LLL,

Why don't you do your own homework, and CONTACT GRUMMAN!
I'd be willing to bet they'd be happy to provide you with all sorts of obscure technical data that is now un-classified pertaining to the LM DPS operation...data that's irrelevant to system OPS, of course from an operator standpoint.


But please, don't tell them why your asking!

If you do that, you're liable to be put in your place in a most ignominious fashion. Don't tell them that their LM, which they spent a decade developing and sucessfully fabricating, and testing, and monitoring on many an Apollo mission, couldn't have done what is was designed to have done, and proven to have done.

I'm afraid you're probably correct Cz....





Yes...there's that too, which is rather unimpressive....

Thank you for your well considered and timely response.

And, thanks to all who have participated in this enlightening topic.

And, lest I forget- mrbusdriver has contributed some excellent views.

this is not a dynamic pressure at all , you didn't made density x velocity suqared / 2 , and this is the dynamic pressure operation , so what is the density and where did you multiply by velocity suqared anywhere on that operation ? and how did you found m° ? it seems to come from nowhere at 3,71 , so you just divided thurst bu area and got p=F/A at the end while this is not the dynamic pressure calculation but the static one , since 2560 isn't the total dynamic pressure but the thrust , that's not just for fun that i said that we need density and velocity datas , because that's what is supposed to give us the dynamic pressure , straight from nasa site , dynamic pressure is density x velocity squared / 2 , how this p=f/a calculation could give the same result ?.

LLL,
YOU made the claim that we did not land on the Moon...YOU made the claim that there should have been a crater under the LM. YOU made the claim that the dynamic pressure was sufficient to do so.
I'm sure the information you seek is out there, don't go on crying becaust Trini won't do YOUR homework for you. Do some research.

you probably didn't read any of my post i guess , because i never made any claim about how that dynamic pressure would be enough , for the simple reason that i didn't kno wthat dynamic pressure , for the main reason that we need datas that i don't know if they ever exist anymore and/or have ever existed at all , (density and velocity of the exhaust gas at nozzle exit) to make the operation at least , BUT i do claim that we should see a crater under that nozzle , based on the official moon landing videos (especialy apollo 14 one that MID didn't see at all it is now obvious with his last few posts) , and i do claim that static pressure , that is always given as a 'proof' for tha no crater issue is totally irrelevant , that's why i say we need the dynamic pressure .

i think i know why you think that MID , you think i ignored your reply about radiations in the VAb's ? "they spent 2,4 minutes in the belts" how can i forget that ! i laughted about 5 days straights on that one ! , no i didn't ignored your reply , i just checked the documents you've mentioned , and try to find comparison , also i 'building' a little personal little database of various radiations figure currently , and reading some documents about radiations , so i will answer later to your reply , just in case you think i ignored it for who know what reason (thinking i was 'killed' on that reply maybe ? , in a way i hope you think that , but i don't know if you can even start to understand why i would like you to think this ...)

for the "copying that equation" , yes i did copy (not copy-pasted but same result i agree) that equation on the nasa site , because i am not a rocket scientist , and never claimed to be , but i wanted to mention that his equation wasn't the same , (missing exit pressure and area) , so i didn't have to reinvent the wheel just for that i guess .

oh , and MID by the way , when you team-up to make fun of me , don't forget your thumb's up , it's seems less serious without your famous idiotic thumb up all around .

I'm not going to get into this whole debate about the DPS exhaust pressure etc. since the maths are just a bit above my level of understanding.

However, in the LM Handbook, Section 2.3 is devoted entirely to the DPS and gives exhaustive details and information about it components and operations. Perhaps if you were to look through this 30-page section, you might find the information you're looking for to do you calculations.


Cz

LLL, you have no idea what you are talking about. You can't just go on wikipedia and expect to work this stuff out. For a pressure exerted on a surface by a moving fluid, the static pressure is equal to the velocity pressure, so the normal P=F/A applies!

that's the precise section i've read already (that's why i said it took me 10 minutes and not 6 months) and i didn't find the data i wanted in that section.



i think you almost have a point there , i have no idea what YOU are talking about right now , i can perfectly understand that at equal density a moving flow will have an higher pressure on a surface than a static one sorry , so what is the density and velocity of that exhaust gas at nozzle exit ?

LLL, why would NASA "place" an Earth into a photo that they knew was too small?

I think it may be time to cut to the chase here, LLL.

I don't care if you ignored my replies to the Van Allen thing. I actually don't care about the Van Allen radiation question, as it has already long been established that this radiation was not an operational problem. The data is conclusive.

You may collect all the information you like. However, understanding what's already been said, as well as the nature of radiation and its measurement and what those measurements actually mean, would be a big help before you begin to spout off again.

Radiation, was the least of my concerns pertaining to Apollo. The data collected is conclusive, the planning for it was more than adequate, and the reports on the results on all the men who passed through the belts sealed the deal. No effects.

As to thinking you were killed by my reply, which ever one that was, no, I was not thinking that. You killed yourself early on with your declarations of fact in the absence of any working knowledge about that which you speak.



You keep asking this question as if it's somehow relevant to your declaration that a blast crater should've appeared beneath the LM on the lunar surface.

Look...you're not a "rocket scientist" by your own admission. Most people aren't. In your case this is clear.
You're looking for detailed technical information from the design and operational phases of LM DPS development.

I've already told you where to go to ask about this...and, how to ask about it, so as not to get yourself completely humiliated.

There are several available sources for LM data, as I've said. However, you had better realize something:

Grumman is an aerospace engineering firm. They design and build commercial aircraft, among other things. As such they are required to maintain complete documentation on every single commercial aircraft they build. That is alot of paper, or at least, it was back in the day before huge hard drives.

They also maintained complete engineering data on every LM they built. The documentation for each vehicle would fill up an average ranch house.
When the program was over, they got rid of most of this material...to make room ( a conspiracy of practicality!). There was no reason to keep it. They're an engineering firm, not an historical archive facility. Any engineer would understand why Grumman didn't keep all of this warehouse full of paper.

However, most assuredly bits and pieces were pulled by some of the people involved with the program. It's possible that someone at Grumman can direct you to those who might be able to help with your queries...unless of course, you tell them that their LM couldn't have worked and should've left a crater on the lunar surface...

Good luck finding it.




No one's making fun of you, LLL.
Frankly, your conduct has been somewhat sad. It's not funny, really.
Those were just observations concerning what is rapidly becoming obvious to all of us. I think it's time you mellow out a little.

This is not about arguing with you. You can't win one of those here.
You should honestly approach this as a potential learning experience, as I've said before.

The radiation issue was long ago dead.
Whatever your issue is regarding blast craters under the LM, that of course is also dead, because no LM ever left one, for rather obvious reasons.

Perhaps you should now go to Grumman and ask about your data set.
When and if you ever get it, you'll of course need to relate that to your idea that the DPS at perhaps 15% throttle, maybe less, should've produced a crater in the hard lunar substrate. You'll of course need to know alot of data relating to the substrates density, cohesiveness and hardness, and then be able to show that a given velocity of exhaust gas would fracture and disperse that hard substrate...and of course, how deep it should be able to cut a hole in it...and then, of course, be able to prove this beyond a shadow of a doubt, while also showing precisley how all those photos of the DPS bell sitting there above the un-cratered lunar surface were faked...

You have alot of work to do.

Of course, it would be alot easier to learn something about Apollo in the first place before setting out on the impossible task you seem to have outlined for yourself.

So, LLL, you claim there should be a crater without know any dynamic pressure data on the engine exhaust...you simply look at landing videos of dust being blown away and determine there must be a crater.
Yes, it was blowing dust...how much? What was under the dust...more dust? Compacted soil? Rock?
Photos clearly show the scouring/erosion of the surface, even some heat discoloration, under the engine bell. How many inches of soil were "blown away" during the landing? Perhaps your "crater" is right in front of you, but is so shallow and diffuse it's all but impossible to observe.

BTW, why should an exhaust plume create a "crater"? I've seen object impacts create craters, but can't recollect a picture of a "crater" caused by a rocket exhaust plume, particularly in a vaccuum.

I have deleted habibi45678 post's for obvious reasons and remind all that offensive language, personal attacks, spamming and flame-baiting are not acceptable behaviour and are in clear violation of UM rules. Should others resort to such behaviour you will be dealt with accordingly. Please keep the discussion civil and constructive.

Thanks for the fast response, AztecInca


Cz

the datas don't say much , the most detailed being apollo 10 where the departure and return figures are shown
ascent max 3,63/h rad return max 0,21/h rad (such a big difference in radiations for ascent and return is already suspicious by the way)
for apollo 11 , 12 , 14 , 15 , 16 , 17 , we don't have those details ,
then apollo 13 , ascent 2,27/h rad return unknown ... (total overall 0,24 rad)
apollo 11 , total 0,11 rad in the VAb's in a total of 0,18 rad , so plus ~192 hours in cislunar space where they allegedly take 1 milirad/h that makes 0,19+- rad already (not counting the EVA , where they should take more than that , i would say about 4 times more minimum) , so 0,11 + 0,19 = 0,30 rad , already apollo 11 is looking faked there.
apollo 12 , show a total of 0,97 rad in the VAb's (while the official total is 0,58 rad...)
apollo 14 tells us they received a total of 0,65 rad in tha VAb's , and it is supposed to be the largest dose of all apollo missions (but as we just see apollo 12 had more ... ) , total overall 1,14 rad for A14

then for missions 8 , 15 , 16 and 17 , no information for tha VAb's radiation exposure at all it seems.



well , it is the least of your concern , no problem about that , but unfortunately it is the major concern for current and future manned space flight (including low earth orbit ones ).

just a little example , directly from the SRAG site :

"..As NASA ponders the feasibility of sending manned spaceflight missions back to the Moon or to other planets, radiation protection for crew members remains one of the key technological issues which must be resolved..."

source.



you prefer that i stop asking question and accept the obviously wrong static 1,5 psi figure that should explain why there was no craters under that nozzle ? , sorry i will not take that 1,5 psi figure for granted , in the same style , i did not accept as valid alternative your flagpole rotation theory on the moving flag issue.



i was looking for detailed information only because of the false argument that is the 1,5 psi , because i mostly base my claim that there should be a crater under that rocket engine nozzle by looking at the very official landing video , nothing less than that , the dynamic pressure would be a nice addition of course , and could only confirm what we've seen on the video , yet i didn't have these density and velocity datas at nozzle exit , so , for now i will do without .



only for you apparently , and once again , i have no problem with that , you are totally free to fool yourself by pretending that the radiation issue is dead.



these rather obvious reason have to be more obvious than the landing videos then , can you point these obvious reasons ? because the landing video show a constant blowing-away of dust as long as the engine is ON , and should exhibit a crater under these nozzle , at least this is obvious for me , how long didn't you saw the apollo 14 landing video for example ?...



you mean northrop grumman right ? grumman don't seems to exist anymore , so i don't see what i could obtain from
an dead grumman company , beside this , according to you they have just get rid of their ranch full of documentations about their historical vehicles , so what next ...

- edited correcting mistakes -

Here's the entire entry from the Apollo 10 Mission report

From the Apollo 10 mission report:
"The personal radiation dosimeters provided an onboard reading of the total integrated radiation dose received by each crewman. This dose was 470 millirads for the flight. Three passive dosimeters containing thermoluminescent powders were also carried by each crewman to measure the total radiation at chest, thigh, and ankle locations. The following readings, all well below the threshold of biological damage, were obtained after the flight.

Total dose, millirads (Chest - Thigh - Ankle)
Commander: 410 - 386 - 460
Command Module Pilot: 560 - 465 - 550
Lunar Module Pilot: 470 - 455 - 450

The Van Allen belt dosimeter provided a telemetered measurement of the rates of ionizing radiation inside the command module. During ascent through the belts, the maximum radiation rates measured were 3.63 rad/hr for a skin dose and 2.09 rad/hr for a depth dose. The maximum rates during the return to earth were 0.21 rad/hr for skin dose and 0.16 rad/hr for depth dose.
The total adsorbed radiation dose for each crewman was approximately 0.5 tad, well below the medically significant threshold. Results of radio-chemical assays of feces and urine and an analysis of onboard nuclear emulsion dosimeters will be presented in the supplemental medical report."


Really?

Explain then how I found these in their respective Mission Reports:

Apollo 11
"12.2.4 Radiation
The personal radiation dosimeters were read at approximately 12-hour intervals, as planned. The total integrated, but uncorrected, doses were 0.25, 0.26, and 0.28 rad for the Commander, Command Module Pilot, and Lunar Module Pilot, respectively. The Van Allen Belt dosimeter indicated total integrated doses of 0.11 rad for the skin and of 0.08 rad for the
depth reading during the entire mission. Thus, the total dose for each crewman is estimated to have been less than 0.2 rad, which is well below the medically significant level. Results of the radio-chemical assays of feces and urine and an analysis of the onboard nuclear emulsion dosimeters will be presented in a separate medical report.

The crewmen were examined with a total body gamma radioactivity counter on August 10, 1969, after release from quarantine. No induced radioactivity was detected, as based on critical measurements and an integration of the total body gamma spectrum. The examination for natural radioactivity revealed the levels of potassium 40 and cesium 137 to be within the normal range."

Apollo 12
"10.2.5 Radiation
Initial estimates of radiation dosage were determined from the personal radiation dosimeters worn by each of the crew and from the Van Allen belt dosimeter. The final readings from the personal radiation dosimeters yielded net integrated (uncorrected) doses of 690, 630, and 640 mrad for the Commander, the Command Module Pilot, and the Lunar Module Pilot, respectively. The Van Allen belt dosimeter displayed integral doses of 510-mrad depth dose and 970-mrad skin dose for the command module. The personal radiation dosimeters and the Van Allen belt dosimeter skin-dose sensor did not integrate comparable doses during the return passage through the Van Allen belts, although it was predicted that the readings would be nearly equal. The possibility exists that the personal dosimeters were stowed in a way that increased radiation shielding.

Approximately half of the total dose recorded on the personal radiation dosimeters was received during the phase Just prior to entry. This disparity was expected because of a different trajectory which resulted in a longer traverse through the Van Allen belts."

Seems like there is some pretty detailed information in those reports after all. Funny how you missed all that.

As for the other missions:

Apollo 14
"10.2.5 Radiation
The Lunar Module Pilot's personal radiation dosimeter failed to integrate the dosage properly after the first 24 hours of flight. To ensure that each lunar module crewman had a functional dosimeter while on the lunar surface, the Command Module Pilot transferred his unit to the Lunar Module Pilot on the fourth day of the mission. The final readings from the personal radiation dosimeters yielded net integrated (uncorrected) values of 640 and 630 millirads for the Commander and the Command Module Pilot, respectively. No value can be determined for the Lunar Module Pilot. The total radiation dose for each crewman was approximately 1.15 rads to the skin and 0.6 rad at a 5-centimeter tissue depth. These doses are the largest observed on any Apollo mission; however, they are well below the threshold of detectable medical effects. The magnitudes of the radiation doses were apparently the result of two factors: (1) The translunar injection trajectory lay closer to the plane of the geomagnetic equator than that of previous flights and, therefore, the spacecraft traveled through the heart of the trapped radiation belts. (2) The space radiation background was greater than previously experienced. Whole-body gamma spectroscopy was also performed postflight on the crew and indicated no cosmic ray induced radioactivity."

Apollo 15
"10.2.4 Radiation
The Commander’s personal radiation dosimeter failed to integrate the dosage properly after the first 24 hours of flight. In order to have functional dosimeters on each lunar module crewman while on the lunar surface, the Command Module Pilot transferred his unit to the Commander prior to lunar module intravehicular transfer. The final readings from the personal radiation dosimeters yielded net integrated (uncorrected) values of 360 millirads for the Commander and 510 millirads for the Lunar Module Pilot. The passive dosimeters worn continuously by all crewmen during the entire mission yielded an average of 300 millirads at skin depth. This dosage is well below the threshold of detectable medical effects."

Apollo 16
"10.2.4 Radiation
The personal radiation dosimeters showed the total absorbed dose to the crew was approximately 0.5 rad at skin depth. This is well below the threshold of detectable medical effects.

This was the first Apollo mission in which three minor solar flares occurred. Although the nuclear particle detection system registered a slight increase in proton and alpha particle fluxes, no measureable radiation dose increment was received by the crew from these flares."

Apollo 17
"11.2.4 Radiation
The personal radiation dosimeters showed the total absorbed dose to the crew was slightly less than 0.6 rad at skin depth. This is well below the threshold of detectable medical effects.

The Lunar Module Pilot's personal radiation dosimeter read higher than the other two crewmen's units, due to atypical performance of the dosimeter at low dose rates."

As to why the amount of information given declines from one mission to the nest, perhaps they noticed that, as they predicted, the radiation issue wasn't all that much of a concern, so there was no need to report as much detail on something that had so little impact in the missions.



From the Apollo 13 Mission Report:
"9.2.6 Radiation
The personal radiation dosimeters were inadvertently stowed in the pockets of the crewmen's suits shortly after lift-off. The Command Module Pilot's dosimeter was stowed at 23 hours and was hung under the command and service module optics for the remainder of the mission. The final reading from this dosimeter yielded a net integrated (uncorrected) dose of 410 mrad. The other two dosimeters yielded net doses of 290 and 340 mrad.

The Van Allen belt dosimeter registered a maximum skin dose rate of 2.27 rad/hr and a maximum depth dose rate of 1.35 rad/hr while ascending through the belt at about 3 hours. Dose rates during descending belt passage and total integrated doses were not obtained because of command module power-down and later, by the absence of high-bit-rate telemetry during the entry phase.

The crewmen were examined by total body gamma spectroscopy 30 days before flight and 6 and 16 days after recovery. Analyses of the gamma spectrum data for each crewman revealed no induced radioactivity. However, the analyses did show a significant decrease in total body potassium (K_0) for each crewman as compared to preflight values. Total body potassium values determined on the second postflight examination had returned to preflight values for each crewman.

The absorbed dose from ionizing radiation was approximately 250 mrad, which is well below the threshold of detectable medical effects. The crew-absorbed dose from the neutron component of the SNAP-27 (part of experiment package) radiation cannot be determined quantitatively at this time. Preliminary evaluations indicated that it was also well below the threshold of detectable medical effects."

So yes, "return unknown" because, as indicated, the CSM was powered down and no telemetry could be sent.




But... didn't you just finish telling us at the beginning of your post that those missions didn't have detailed reports?


If you couldn't find detailed reports, then where did you find those figures? And where did you get your qualifications to say whether they should have been getting "4 times more minimum"? What do you base that on? What evidence can you provide that shows that to be a correct assumption?



15, 16 and 17 were covered earlier. The Apollo 8 Mission report does not contain a section on radiation exposure. It is contained in a separate report:

From Preliminary Clinical Report of the Medical Aspects of Apollos 7 and 8 - May 1969
"Radiation
No concern was felt prior to the Apollo 7 mission, as our experience in Gemini with earth orbital flights had shown only minimum radiation exposure. Prior to the Apollo 8 mission, however, concern was expressed concerning the radiation that might be experienced in going through the Van Allen belts on a translunar trajectory - orbiting the moon and return. Our calculations led us to believe that if no solar flare occurred, the maximum radiation levels encountered would be approximately 200 millirad . The actual radiation dose in the cabin as determined by the personal radiation dosimeters was 200 millirad. The passive dosimeters on chest, thigh, and ankle varied from 133 t o 177 millirads +/- 10 percent."

and

"CONCLUSIONS

It is evident that the Apollo spacecraft is capable of supporting man adequately in a space environment from a physiologic point of view. It appears that the spacecraft environment offers no undue hazard, and radiation levels have not proven to be significant in the flights thus far."



Yes, and no one, anywhere has ever tried to claim that radiation protection was NOT an important issue, but rather that it was studied, the risks assessed and managed as best as they could. The findings I quoted from the Mission Reports prove that the spacecraft and the spacesuits were more than capable of protecting the astronauts during a mission of the duration experienced during Apollo. Notice in the quote you provide the use of the phrase "the feasibility of sending manned spaceflight missions back to the Moon or to other planets" which obviously indicates that NASA is looking at missions of different types and of longer durations than those of Apollo. And if you'd have read some of the other responses earlier about the radiation "issue" there are other good, logical reasons for NASA to do current radiation research.


And you can continue to fool yourself in believing you have ANY idea of what you are talking about with the "radiation issue" OR with the "crater" issue. Its amazing how these things are so "obvious" to you but have managed to escape the almost 40 years of scrutiny by scientists, technicians and engineers who have actual training and qualifications in their fields.


You OBVIOUSLY didn't read the rest of MID's post because if you did you OBVIOUSLY would have seen this:



So what you OBVIOUSLY missed there was MID's OBVIOUS suggestion that perhaps, if someone at Northrop Grumman can't give you a direct answer themselves, they could possibly point you in the direction of someone who could.

Its called RESEARCH and it is something you also OBVIOUSLY have no idea how to do.


Cz

EDITED for typos...

nothing that i didn't know (since i've read this same document) , but thanks for the double checking.



i did found the same datas in the same mission reports , thank you for the double checking again , and where are the details contained in the apollo 10 one ? ascent max dose , entry max dose ? that's the details i was talking about .



see above ...



oh you mean , and in the others missions reports that i supposedly didn't read , even if i mentioned that i checked the documents listed by MID in is radiations reply ? and even if these documents are the same that the documents you just copy-pasted large portion of ? , ok let's see what i 'missed' then ... , hope it's interesting.



ok nothing new there , 0,30 rad is the total radiation dose , not the VAb's specific details at all , next.



ok 0,50 rad is the total radiation dose , not the specific VAb's radiations figures , next.



0,6 rad ok , the official (probably corrected value) is 0,55 rad , so this is the total radiation dose and not the specific VAb's radiations doses , proving my point that 8 , 15 , 16 , 17 have no details concerning the VAb's radiations dose , that's just what i wanted to say.



did you think i meant anything else than that ? except confirming that the return is unknown what do you have ?
i said return unknown , what the hell to you think i meant beside WE DON'T KNOW THE RETURN DATAS ! ??

and 0,24 rad is the total radiation dose , as for the 2,27 rad/h max i did mentioned it , thanks for the double checking again anyway.



for apollo 11 i was talking about the lack of specific ascent and return datas , but i did mentioned the 0,11 rad already , and then i added an estimation based on the official alleged cislunar radiations figure (1 milirad /h) of the remaining 192 hours (estimating a ~3 hours LEO of the 195 hours total mission time) , that should have yelded about 0,19 rad (192 milirads to be precise) , so 0,11 rad (of the VAb's plus 0,19 rads is 0,30 rad , yet the official radiation dose of apollo 11 is 0,18 rad.



4 times more minimum is an estimation based on a document* where they monitored radiation in LEO on EVA's , and the radiation where roughly 3 to 4 times more in EVA , so i estimated , since the GCR are in a wider spectrum outside magnetosphere , i don't see how it could be less than 4 times more at least , in fact i am probably well optimistic in this estimation , and by the way for example , an estimation of F,Cucinotta state that they would have taken 11 times more radiations in their 0,25g/cm2 shielded suits , than in the Command Module (8g/cm2 shielding) in case of encountering the famous 1972 solar flares (just to give an idea) , so considering outside there is also a wider spectrum of solar radiations , even without major solar flares by the way , just in general , my 4 times more figure estimation is certainly highly optimistic , it was just to not overdone it.

-edit- * source. page 18 "..A single set of data exists that records doses received to an astronaut and a cosmonaut exclusively during EVA (Deme et al., 1999). During low solar activity (29 April, 1997), the Hungarian Pille TLDs were
worn in a pocket on the outside of the Orlan-M space suits. Measured EVA absorbed dose rates were between 60
and 80 mGy hr-1, approximately 3 to 4 times higher than the contemporaneous dose measured inside the station.."



where ? except total radiation dose i didn't see specific VAb's ones , and for the apollo 8 mission , no luck as well , this is also the total radiation dose , and not the specific VAb's one , (0,16 rad official total radiation for apollo 8)



it is evident for me , that the apollo craft where capable of supporting man adequately (if their 8g/cm2 alleged shielding is anything real) in LEO for sure , i don't think (in fact im pretty sure about that) that they had ever crossed our protective magnetosphere once .




for sure , longuer duration mission put an even bigger risk radiation-wise , but in this case , they speak about any mission , they didn't only mention longuer mission , but just any single possible mission , simple as that , ans they think the problem isn't solved yet , but in the seventie's it was solved right ? maybe grumman lost the miracle technology that solved the problem in their ranch ? someone know where is that 'full of documents' ranch ? it would be quite an amazing find for the current scientific community i guess.




oh i see , you didn't like that word ? sorry then , english is not my mother language and i tend to repeat myself with a limited vocabulary i agree , i will try to vary a little , but i do like this word , it is simple and effective.

-edited to correct mistakes-

"Prior to the Apollo 8 mission, however, concern was expressed concerning the radiation that might be experienced in going through the Van Allen belts on a translunar trajectory - orbiting the moon and return. Our calculations led us to believe that if no solar flare occurred, the maximum radiation levels encountered would be approximately 200 millirad . The actual radiation dose in the cabin as determined by the personal radiation dosimeters was 200 millirad. The passive dosimeters on chest, thigh, and ankle varied from 133 t o 177 millirads +/- 10 percent."

I don't understand what the "problem" is here. Scientists estimated the amount of radiation astronauts would receive during a Moon mission, and then that "estimation" as confirmed by actual measurement.


End of story...

Perhaps then, to avoid further misinterpretations, when posting figures you should post where those figures are from.

I'm rather unclear on your insistence that the lack of specific dose readings for the transits through the VAB is representative of some sort of cover-up or misrepresentation on NASA's part. The exposure information given is the cumulative dose readings of all exposure during the mission. Are you suggesting that the astronauts should have had separate dosimeters that they wore only when transiting the VAB and then stored them in some kind of lead lined box during the rest of the mission as well as secondary dosimeters to show cumulative exposure?


First, the 1 millirad/hour figure is an estimate, also you are not taking into exposure levels inside the CSM vary slightly depending upon where you are inside it, also, during certain phases of the mission, all 3 astronauts were wearing their full spacesuit, which would further shield them from exposure. And the unadjusted cumulative levels do correspond relatively closely to your estimate, taking into account the variables listed.



Can you please provide a reference to where Francis A. Cucinotta specifically states this? So far I have found a lot of documents to which he is attached, usually as part of a group of researchers (a search for his name at the NASA Langley Technical Report Server brings back about 60 results, and I'd rather not read all of them). A lot of the reports he has been involved with deal with radiation shielding as it relates to long duration interplantary (and possibly interstellar) missions, although admittedly a few of the abstracts I read did deal with Lunar missions, but again, ones that involve longer durations than any of the Apollo missions.

Again, though, I am curious as to how the levels of exposure that the astronauts might face if there had been such a large solar event as the famous 1972 event relate to the documented exposure levels they DID face during while there were no major events recorded. It has already been put forth that NASA put great importance on the study of solar flare events and, while it was not possible to predict specific events, they were able to predict the most likely times for such events to happen and planned the Apollo mission around those estimated times. In addition to that there were procedures already in place should they have been caught by surprise by an unexpected solar flare event or CME.



If I am understanding this correctly,what you are saying is that the exposure levels should be 4 times higher than those recorded during solar minimum, and your basis for this figure is your "conservative estimate" based upon a statement that deals not with "every day" solar radiation, but one of the largest solar events on record. Is that about right...?

And please provide your source for the "wider spectrum of solar raditaions" you used to further refine your estimate.


Key point - "the Hungarian Pille TLDs were worn in a pocket on the outside of the Orlan-M space suits".

That says nothing of the dose experienced by the astronaut inside the protective spacesuit.

You're taking one individual set of data that discusses one finding during LEO EVA activities and applying that to EVA activities on the Lunar Surface...? or rather the whole mission? How do you justify that leap of logic?

You do realize that the document you're quoting specifically talks only about LEO EVA's, right? That it mentions nothing (as far as I could gather from the parts of the report concerning your quote that I read) about nor makes any comparisons to EVA activities on the Lunar surface or in Cislunar space?



Now you're just being argumentative. The report you cited talks about radiation studies for future missions. Since it is already established that future missions will be of longer duration, your assertion that they were actually talking about the Apollo missions has no basis in fact, whatsoever. The problem was solved, or rather the risks were managed for the Apollo missions.



No offense was intended towards your language skills, which are a lot better than some others we have seen in this forum.

You say that things are so obvious to you, yet you did not address this:





Cz

I mostly have the feeling that you just quickly read my post , then tried to 'pin' me on the radiations issue , assuming that i didn't read anything (thinking that i can't even read maybe ?) , but hey you are maybe right trying to put the blame on me is also a nice tactic coming from you , no big surprise , im sure MID would have loved to put a thumb up on that one heh ?.



they had secondary dosimeter for the VAb's reading , if not they couldn't have obtained these 3,63 rad/h max for apollo 10 for example , since the personal dosimeter didn't registered total dose of 3,63 rad , even if it would be possible to estimate this based on two reading of the total dose , i bet they have better things to do in LEO than to fake VAb's estimation with personal dosimeter anyway.



it is an estimation yes , just in case you didn't know that also mean it could be higher (you seems to pretend it can only be lower heh ?) , but we don't have any other estimation around no ? so this 1 milirad/h (2 at solar low+-) seems to be the good one to make an estimation , of course i don't take this 1 milirad/h very seriously , but again , i don't have personal alternative source estimation of cislunar radiation , so i just take that , but this 1 milirad/h by the way , seems to be an 'ideal' estimation , because they claim it double at solar low , meaning this is the GCR background radiation estimation only , that mean the total radiation in cislunar space is probably higher than this , since it contain every possible solar events radiation in addition , probably not counted in that 1 milirad/h estimation, for the simple reason that they are unpredictable , even to this day , why i say that you think ? simple , they say this 1 milirad/h will double at solar low , and GCR do fluctuate according to solar cycle , less in solar maximum and more in solar minimum.



source. at 3/4 of the page , ".. says Cucinotta. An Apollo command module with its aluminum hull would have attenuated the 1972 storm from 400 rem to less than 35 rem at the astronaut's blood-forming organs.."

400 rem compared to 35 is 11 times more.



major event is something , the problem is you can't avoid the fact that , ANY events will increase radiations (and then this idealized 1 milirad/h will increase , no doubt about this) , and the problem is , they where in solar peak years for the major parts of the whole apollo missions , this alone is enough for me to put extremly high doubts on the official radiations figures of this apollo program.

just an interesting example , for the SRAG site again :

"..Near solar maximum, the Sun produces about three CMEs per day, whereas near solar minimum, it produces about one every five days.."

don't mean that all the CME's will go directly toward the earth/moon direction of course , but still , this is only CME's , and they where 3 per days average , so in a 12 days missions 36 CME's +- ... (not even talking about the solar flares that are also severals per day in solar peak !) , of course when you read the official documents , "everything fine , we monitored the sun , blahblah ..." monitoring the sun don't mean controling the sun , they could just have saw the damage aftermath , nothing more than that , solar flares and CME's are unpredictable , they only roughly know higher risk period (aka solar maximum period are higher risk of course).

same page than precedent post , but just in case , here the source again.

note that Cucinotta made a pretty 'conservative' estimation on that 400 rem figure , i've seen estimation of 26 Sieverts (skin dose tough) for a 0,50g/cm2 shielding for that same flare figure , note Cucinotta seems to speak about 0,25g/cm2 shielding suits , so 2600 rem ... very unhealthy to say the least.



No , you didn't understanded correctly , the 4 times more is just a ratio EVA , IVA , the fact that this test occured in solar minimum don't change much , since the EVA , certainly didn't occured in the SAA (they avoid the SAA as much as they can for EVA's) , so the main radiations exposure was caused by GCR , and the main radiation outside magnetosphere will be GCR as far as we've been told at least , (plus solar events radiations of course) , the ratio will just be higher outside in my point of view , for the simple fact that outside magnetosphere , there is a wider range and density of GCR energy's and solar radiations as well , and i don't have particular source that i remember right now , because this is just logical , since the magnetosphere is protective (a cocoon by the SRAG own words) , that mean lower energy GCR and solar radiation don't penetrate in LEO altitude (trapped in the belt's and so on) also the highest energy are a bit weakened too , so outside , you have more GCR , more solar radiations , and as a deadly bonus , at higher energy than in the cocoon of the magnetosphere.



it is a point , not a key point in my point of view , because it would not make any sense to monitor EVA's radiation with totally irrelevant radiations at the end , so these dosimeters even in an exterior pocket , where probably shielded and/or put same shielding condition than the spacesuits , it wouldn't make sense to take these radiations for anything else than 'pocket survival' if it wasn't the case , and i doubt anyone care about the survival of a fabric pocket right ? , and why would they mention these radiations at all in a documents about EVA radiations afterall ?



yes LEO EVA's , and outside it would be similar condition but at higher rates of radiations and higher energy , so what's wrong with taking this single LEo estimation to estimate cislunar one ? , beside this , there is very few EVA's radiations figures to compare to , i think i have seen 2 more in some documents i have , but im a bit tired to search them tonight , i will check that tomorrow , but from memory they where confirming this 3 to 4 times higher dose (maybe it was the same one on different document tough , i will see that later).



argumentative ? you mean like your "key point , it was in a pocket..." argument ?

-edited to correct mistakes-

Comparing your original post with the actual text shows that you confused dose and dose rate. For example, the 3.63 and 0.21 rad figures that you quoted as dosages for Apollo 10 were actually peak dose rates in rads per hour. This confusion makes a nonsense of the rest of your post.

.686 g/cm^2 = 100 mils of aluminum. That's 2.54 mm. A tenth of an inch. The CM was built of much thicker aluminum.
The radiation during the short Apollo missions was not a problem.

LLL,
If you believe that someone is breaking the rules of this site then please use the report button and allow the moderators to deal with it. Please do not continue to make accusations like this in the forum. This could be considered flamebaiting and that IS against this forum's rules:

I asked you to clearly indicate when you are posting data from source material and to indicate that source so as to avoid confusing data that you have assumed with data you have actually researched.

Hardly trying to "pin" anything on you, rather trying to make the discussion go smoother and to avoid more misunderstandings. If that is a "tactic" - and the inference in your post is that of it being a ploy on my part to do something against you - in your eyes, then I clearly admit to it.

Yes, LLL, I want your posts to be easier to understand. I want to know where you are getting your information from so I and others can check it out for ourselves. I want to be able to tell the difference between information you are just assuming and information you have actually sourced from somewhere.

I understand that English is not your first language - and I applaud you for the level of competence you have so far shown with it - but there is still some confusion because of this language barrier. If you can make your posts clearer, especially when dealing with quoted information, then we will all have an easier time understanding each other.

If you do see it as a "tactic", again with the negative connotation implied by your post, on my part then one must wonder why you view having your posts easier to understand as a "bad thing".

And what MID does or doesn't do is his business and holds no bearing on the subject of this debate.