An intro..........

[greymick]

Hi everyone,

If I'm breaking forum rules in some way my apologies.

I'm 45 and have two clear memories of the 60's.

Receiving a World Cup Willie bag from my mother, and Neil and Buzz on the surface.

I realise this has been covered in other threads but I've never been that convinced by the answer.

It's just the cheapness of the LM, yep I know it's not pressurised and is just an outer covering, but it looks unbelievably nasty.

The white panels fit where they touch and the bolts?.... seem randomly placed. Is there a reason it looks so haphazard?

I find it hard to subscribe to the explanation that it doesn't really matter that's all.

Rgds

[PeterB]

G'day Greymick, and welcome to ApolloHoax.

I dare say it's going to be hard to give you a convincing answer if you state ahead of time that the answer we're going to give you is unconvincing. But it's the truth.

The earliest plans for the Lunar Module showed a machine which was intended to have rounded corners and a smooth, sleek shape. But it only ever operated in a vacuum. As a result, there was simply no need for it either to be symmetrical or to have rounded edges. What was paramount, however, was to save weight, and so its designers made it the most weight-efficient shape it could be. If that all seems a bit odd, think of the various spacecraft which have travelled to the planets. All of them have bits and pieces sticking out at odd angles, simply because shape isn't an issue in a vacuum.

There's a second factor operating, too. The outer skin of the Lunar Module isn't the pressure vessel. The pressure vessel is actually a cylinder on its side, inside the outer skin of the spacecraft. The purpose of the outer skin was to provide thermal protection, and protection against meteorites. It therefore only needed to be as good as it needed to be in order to do that job. It didn't have to be pretty, and it certainly didn't have to be airtight.

I've already mentioned it, but it bears repeating - the factor which underlay nearly all design decisions for the Lunar Module was weight. New techniques for milling metal had to be specifically created for the construction of the LM because current techniques weren't up to the job of milling metal so thinly without weakening it structurally.

I hope this gives you a bit of an idea, but if you want more information, I can highly recommend the book "Moon Lander" by Tom Kelly. Kelly was the engineer at Grumman who was in charge of developing the Lunar Module.

[Jason Thompson]

Welcome greymick.

It's just the cheapness of the LM, yep I know it's not pressurised and is just an outer covering, but it looks unbelievably nasty

Think about that for a moment. 'Unbelivably' nasty. Now if they were trying to fake it why wouldn't they build a LM that looked more like the layman's expectation of what a spaceraft would look like?

The LM is covered in foil and thin panels because it is lightweight but still functions. Looks are not important. And with no air resistance ever posing a problem for it, it really doesn't matter too much how the outer skin is attached.

[Czero 101]

Two pictures of the LM Ascent stage pressure vessel without the outer skin.


(image from Eric Hartwell's "SCA/T Remembered" website)


(image from Eric Hartwell's "SCA/T Remembered" website)

Design history of the LM:

1962

(image from Eric Hartwell's "SCA/T Remembered" website)

1963

(image from Eric Hartwell's "SCA/T Remembered" website)

1965

(image from Eric Hartwell's "SCA/T Remembered" website)

Final design (LM 2 on display at the National Air & Space Museum, Washington DC)

(image from Wikipedia - Lunar Module)

Lots more information can be found at Trinitrotoluene's website:

LandingApollo.com - Lunar Module Documentation


Cz

[greymick]

Hi Guys,

Thanks for the welcome

I have no desire to labour the point, it just jars on me when I see a high def picture of the LM on the lunar surface.

Cheers

[Czero 101]

The LM was not made to be pretty, but it was eminently functional and exceeded all expectations on its missions. Keep in mind that the aluminum panels were very thin and to save weight they didn't use as many rivets or connectors as you would find on say a jet. Sometimes, all they used was tape to keep the corners together.

Launching a vehicle into orbit causes a lot of stress on the vehicle, so some of the panels probably got a little warped at that time. If the landing was a little rougher than expected, that could also have warped a plate or two. Also, lifting off from the lunar surface caused a lot of stress and as can be seen in the photo below of the back of Apollo 16's LM Orion, the panels got really messed up:




Cz

[gwiz]

The thing is, cheap looking foil covering is an excellent engineering solution for thermal control in space, provided the vehicle doesn't have to also work in an atmosphere. Google up a few pictures of modern communications satellites - they mostly have foil covering a large part of the surface.

[RAF]

czero101 said:

...as can be seen in the photo below of the back of Apollo 16's LM Orion...

When I read the OP, that was the exact image that came to mind...

[scubadude402]

a long, long time ago i remember being shocked to learn that you could drop a screwdriver through the skin of the LM. I, like a lot of people, thought that spacecraft were suppose to be"bullit-proof". But i as read and studied ( Moon Lander and Chariots of apollo are excellent sources of info to get you started) i learned that spacecraft are built to be exactly as strong as they need to be to operate in there intended enviroment. You say that the LM looks "cheap" and "nasty". maybe it does to some,but remember that there are a lot of areospace engineers in this world that also are looking at it and have no problems at all with the way it's designed. when you actually understand what it is you are looking at you will see that it is actually a marvelle of engineering. For instance the ladder from the hatch looks impossibly flimsy to support a man with all his support gear,but when you learn that the moon has 1/6 of the earths gravity you see that it's designed perfectly to support it's intended load on the moons surface. Best thing that i can tell you to do if you have any doubts is to read and study all the available material and you'll find your doubts quickly subsiding.

[wdmundt]

Another way to look at it is that many different kinds of problems had to be solved for the LM to work, and those problems were solved in a variety of ways. The looks of the thing were given around zero attention. The ultimate combination of the solutions may look nasty to some, but it looks like problem-solving genius to others.

I, for one, love the look of the LM.

[JayUtah]

The thing is, cheap looking foil covering is an excellent engineering solution for thermal control in space...

Yep, and tape is the best way to stick it on.

The ascent stage did have a rigid skin of very thin aluminum sheet. And it was fastened over an insulation blanket, etc. All it had to was hold the insulation in place, keep the sun off the inner skin, and absorb incoming micrometeoroids. They don't have to fit perfectly. They just have to not fall off -- and even that's somewhat optional.

I'm not sure what would convince you that the precision of the outer skin doesn't matter. Some aerospace fabrication techniques require millions of dollars of research and equipment. Others are not much harder than hanging drywall.

[Bob B.]

From the Apollo Spacecraft News Reference…

THERMAL AND MICROMETEOROID SHIELD

After the LM is removed from the spacecraft-Lunar Module adapter (SLA), it is exposed to micrometeoroids and solar radiation. To protect the LM astronauts and equipment from temperature extremes, active and passive thermal control is used. Active thermal control is provided by the ECS. Passive thermal control isolates the vehicle interior structure and equipment from its external environment to sustain acceptable temperature limits throughout the lunar mission. The entire ascent stage structure is enclosed within a thermal blanket and a micrometeoroid shield. Glass fiber standoffs, or low thermal conductivity, hold the blanket away from the structural skin. Aluminum frames around the propellant tanks prevent contact between tanks and blanket. The thermal blanket consists of multiple-layered (at least 25 layers) of aluminized sheet (Mylar or H-film). Each layer is only 0.00015 inch thick and is coated on one side with a microinch thickness of aluminum. To make an even more effective insulation, the polymide sheets are hand crinkled before blanket fabrication. The crinkling provides a path for venting, and minimizes contact conductance between the layers. Structures with a high thermal conductivity, such as antenna supports and landing gear members, that pass through the thermal blanket also have thermal protection. Individual blanket layers are overlapped and sealed with a continuous strip of H-film tape. To join the multilayered sections, the blanket edges are secured with grommet type fasteners, then the seam is folded and sealed with a continuous strip of tape. Mylar sheets are used predominantly in the areas where temperatures do not exceed 300^o F. In areas where higher temperatures are sustained, additional layers of H-film are added to the Mylar sheets. H-film can withstand temperatures up to 1000^o F, but, because it is a heavier material, it is used only where absolutely necessary. Certain areas of the ascent stage are subjected to temperatures as high as 1800^o F due to CSM and LM RCS plume impingement. There areas are thermally controlled by a sandwich material of thin nickel foil (0.0005 inch) interleaved with Inconel wire mesh and Inconel sheet. Finally, the highly reflective surfaces of the shades provided for the front and docking windows reduce heat absorption.

The micrometeoroid shield, outboard of the thermal blanket, is a sheet of aluminum that varies in thickness from 0.004 to 0.008 inch, depending on micrometeoroid-penetration vulnerability. It is attached to the same standoffs as the thermal blankets. Various thermal control coatings are applied to the outer surface of the shield to provide additional temperature boundary for vehicle insulation against space environment.

So what we see on the outside of the LM ascent stage is an extremely thin aluminum sheet, only 0.004 to 0.008 inch thick, held in place with standoff supports. A layer that thin has little rigidity and as few standoffs as necessary was used to minimize the weight. As a result the outer layer looked very flimsy, but it was lightweight and effective. Whether or not is looked pretty was not a consideration. The outside looks as it does by design.

The thermal protection of the descent stage was very similar except it did not include the micrometeoroid shield; we therefore see the thermal blanket directly. As described in the NASA documents, this blanket was intentionally crinkled to improve its effectiveness as insulation. It may look sloppy to the untrained eye, but it is common practice. Look at a photo of any spacecraft today and you will see the same crinkled appearance as seen on the LM.

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[Ginnie]

I agree with wdmundt. The LM looks beautiful. You couldn't make something like that up if it didn't have the purpose of actually going to the moon.

[sts60]

Hi, greymick, and welcome. You might also take a look at the Photos of Armstrong thread where we belabored this issue at some length. I don't have anything else to add to the other responses here except that "haphazard"-looking placement is partly the result of the engineers figuring out where different levels of thermal protection were needed.

[gillianren]

greymick said:

Hi Guys,

Thanks for the welcome

I have no desire to labour the point, it just jars on me when I see a high def picture of the LM on the lunar surface.

Cheers

Why is this one thing enough to convince you? What about every other piece of evidence--and there are thousands? If this one thing doesn't seem right to you, but there are thousands of others, doesn't that mean that it's more likely to be your assumptions that are wrong, not the thing itself?