Viking '75 Mars Lander Construction, Looking for Viking lander design/construction information Options

[Tom Dahl]

Greetings all! I am searching for detailed construction and design information about the NASA Viking '75 Mars project hardware, particularly for the lander, aeroshell, base cover, and bioshield. Can anyone recommend good sources? I am especially looking for engineering drawings and under-construction photographs.

To set the stage, here is an album of about 100 drawings and photos which I've collected so far:

https://picasaweb.google.com/11379204157387...feat=directlink

I have already read the "usual" books, such as NASA RP-1027 "Viking '75 Spacecraft Design and Test", the press kits, the scientific papers produced about the mission, a number of industry papers covering various instruments and subsystems, the major Martin Marietta books, etc. I am hoping to find additional sources. Any ideas?

Also, does anyone know if there are aeroshell, base cover, or bioshield components lurking in a museum or in storage somewhere?

FYI, I have visited three of the best landers still on Earth: The Proof Test Capsule in the Smithsonian NASM, the Flight Capsule 3 (backup) in the Museum of Flight near Seattle, and the Science Test Lander in the Virginia Air and Space Center. I've taken nearly 1,000 photos of the three of them (most of which are publicly available in other Picasa Web albums of mine). I've taken a few measurements, but I would dearly love to find more authoritative drawings of more hardware (interior, exterior, everything). I have begun submitting some Freedom of Information Act requests to NASA/JPL which has started to bear some trivial but kind of fun fruit.
-- Tom

[tasp]

Can't remember where I read this, but at least one piece of a spare aeroshell assembly wound up in someones backyard.

Seems like I saw a pic somewhere. Maybe Sky and Telescope a LONG time ago.

[Tom Dahl]

I have begun creating a 3D model of the Viking lander, attempting to be fairly detailed and as accurate as I can manage (based on the references I have, including some 900 photographs I've taken of three authentic landers). I recently completed my first pass at the lander's sidebeam #1, which forms one third of the lander's hexagonal body. Here is a comparison between renderings of the model and photographs of the backup lander body in the Museum of Flight near Seattle.

The model linked above represents the solid machined aluminum beam without any of the brackets, fittings, and flanges which are bolted or screwed to the sidebeam. The attachment points for all those brackets etc. are represented as carefully-located bolt holes. As I understand it, each sidebeam consists of a lander-body long side and half of the adjacent two short sides. The three sidebeams are apparently connected to each other via the vertical landing leg primary support fittings, which are bolted across and under the joints between adjacent sidebeams. The top and bottom cover plates also help to hold the body together; fastener locations for those plates are included in the model.

Proportions of the model are based on dimensions I have taken from some authentic landers, various published references, and a lot of photo interpretation and cross-check. I have been careful to ensure that the various points of contact between the lander and its aeroshell are reconciled (three large bolts, one under each leg primary support fitting; six shear points, two under each sidebeam; and three guiderail roller assemblies).

If anyone has corrections or questions, I would be pleased to address them!

[Tom Dahl]

I am looking for a good-quality version of an image published in NASA Ref. Pub. 1027, "Viking '75 Spacecraft Design and Test Summary: Volume 1 - Lander Design" issued by the Langley Research Center in 1980. Figure 20 "Lander Body" (on page 25) is what I hope to find.

The PDF version of RP-1027 Vol.1 (10MB) on the NASA Technical Reports Server has an almost illegible image of Figure 20. I have examined two original printed copies of RP-1027 from nearly libraries; in both cases the original halftone printing of Figure 20 is fairly poor. Here is a version which I scanned at 400 DPI from one of the copies.

Does anyone know if a photographic print or high-resolution scan of that image is available in some archive somewhere? I recently sent a message to the "Contact Langley" web site asking about this image, in case that turns it up.

Edited to add: as a prior reply mentions, I am creating a 3D digital model of the lander. My intention is to make that model freely available, both as a 3D SketchUp mesh and as 2D blueprints. The purpose of the blueprint form is to aid my ultimate goal of scratch-building an actual model, probably 1/8th scale. My collection of published drawings and unusual photos (including "Figure 20" linked above, which shows the lander's internal Equipment Plate) are already shared, in case they help folks also interested in the Viking project.

[Tom Dahl]

I've now completed the first-pass 3D model of the lander's three sidebeams. Here are some comparison actual photos vs. renderings, and one render by itself (sidebeam 3 is in the lower right, #1 on the left, and #2 in the upper right, with meteorology boom mounting bracket attached):



This is only a small fraction of the job, but it's nice to see the shell of the lander in the round.
-- Tom

[Tom Dahl]

For those following at home I have added the Viking lander's top cover plate to my 3D model. It was a challenge to reconcile the externally-visible features with Martin Marietta's drawing of the interior Equipment Plate (instrument locations, support posts, etc.). I've tried to minimize the discrepancies. Here is a line drawing of the overall body:

And here is a close-up of the right upper corner of sidebeam 2. Prominent are the mount for the meteorology boom and magnet cleaning brush (on the right corner), and large openings in the top cover for camera 1 (on the right), the biology and gas chromatograph mass spectrometer inlet processors (on the left), and thermal switch contactor for Radioisotope Thermoelectric Generator 1 (partly visible at top):

The current state of the 3D model is available here as a SketchUp file (6.8MB; hopefully it's downloadable).

I had a very enjoyable phone conversation today with Prof. Jim Tillman of the University of Washington, who along with his daughter were principal agents in saving and restoring the Flight Capsule 3 (backup) lander body. I'm hoping to return to visit the FC3 in the Museum of Flight near Seattle in a few weeks. I'm glad I could share a bit of my enthusiasm for the Viking program with Prof. Tillman and thank him for saving an important historic object.

[djellison]

There is a model - I'm not sure of its fidelity - at the California Science Center. If there are details there that could be useful, let me know and I'll head over with a camera.

Doug

[nprev]

IIRC, they've got the actual ground engineering test lander in the lobby of the National Air & Space Museum in DC. I wonder if the curators there have complied a dataset of public-domain information on same; might be worth an e-mail.

[Tom Dahl]

Hi Doug -- regarding the California Science Center's lander, thank you very much for the offer! I suspect that unit is a replica created by Penwal Prototypes, rather than an authentic Martin Marietta unit. I base this largely on the photo shown on the company's web site (look for the Viking Lander thumbnail), compared to on-line photos I've found of the CSC's lander. Details such as Camera 1's clear housing; the mock-up BIO and GCMS inlet processors; the silver foil bands on some leg's white cloth contamination fairing skins; the dark bands wrapping the meteorology boom cabling; the fuel tank and roll-control thrusters, and fuel-line routing and joints. I wrote to Penwal a few months ago asking about their replica and whatever references they may have had, but never received a response.

Overall I don't think it is authentic enough for my purposes, except I am very curious about the exposed camera 1. Did Penwal manage to acquire a surplus original ITEK facsimile camera unit? It seems out of character with the rest of the lander; too much detail. So I would very much enjoy seeing some photographs of that camera's innards (both the upper rotating opto-mechanical part, and the lower fixed electronics part) from various angles. If possible!

Hi nprev -- that's the Proof Test Capsule in the National Air and Space Museum. I've actually visited it three times in the last year, and accumulated about 460 photos of that fantastic unit. I have not yet attempted to contact the NASM archive division, which I really should do! Thanks for the nudge.

[Tom Dahl]

In September had the opportunity to spend a couple of days at the Museum of Flight near Seattle WA, and study the Viking lander Flight Capsule 3 (flight-backup) on display there. I took over 500 detail photographs of the lander. I recently completed processing (e.g., brighten shadows, diminish background distractions, add captions) and have uploaded them to a Google Picasa web album if anyone else is interested. They join about 180 photos of the FC3 I had taken a year ago.

The images are about 12MPixels in size. If you use Picasa web's magnifying-glass tool to see the full version, it usually takes five seconds or so before the complete image is available. Before then the little zoom-navigation widget only goes to about half size; the bar will re-scale to access the full detail when ready.

I also had a chance to meet Chris Vancil and Eckart Schmidt, both of whom worked to restore the FC3 for display (Eckart worked during the mission at Rocket Research Company on the terminal descent engines), and also Ron Hobbs of the museum staff. It's a great facility with an amazing collection.

[Tom Dahl]

A few months ago I was delighted to acquire a vintage set of blueprints of the "Viking Lander Body Structure Assembly" by Martin Marietta. With the permission of the UMSF administrators I am making scans of them available to all, hoping they provide useful information or at least enjoyable viewing. Here is a PicasaWeb album.

Overview

I suspect this set of blueprints was intended to guide assembly of the core body and its myriad brackets and fittings, rather than to support the fabrication of the various piece parts. There are extensive dimensions listed on the plans (which is what I find so valuable!), but not enough to fully define the parts. The print set consists of 35 sheets. Sheet 1 is composed of over 100 individual pages, consisting of notes, parts lists, and Design Change Notices. Sheets 2 through 35 are the actual shop drawings (one large page per sheet). In the above album I have shown the drawing sheets first, then the various notes pages. What follows in this message are some of my interpretations and explanations of the contents of this historic blueprint set.

Five Lander Body Variants

Martin Marietta's part number for the core lander body is 837J3100000. The plans show five (5) distinct variants of the body, denoted with tags -009, -010, -019, -020, and -029. All five have unique features (generally quite small). Variants 9 and 29 are fairly close to each other; 10, 19, and 20 have a lot in common. I would love to learn what variants correspond to which manufactured lander body units. There is a table on Sheet 1 page 2.004 which seems to list the five body variants with cryptic nomenclature:

ASSY/PART NO. --- NEXT ASSEMBLY --- TT
837J3100000-009 --- 837K0100000 --- PC (?Proof Test Capsule, PTC?)
837J3100000-010 --- 837J1000200 --- TM (?Thermal Effects Test Model, TETM?)
837J3100000-019 --- 837J2000200 --- SD (?Lander Structural Dynamic-Test Model, LDTM?)
837J3100000-020 --- 837J3000200 --- SS (?Lander Structural Static-Test Model, LSTM?)
837J3100000-029 --- 837K0100000 --- <blank>

I don't know the meaning of the "TT" column, but I'll guess that it represents the purpose or role of the lander units (perhaps Test Type). If so, I wonder if the table's two-letter designations represent the test units who's names I've added to the table in parentheses. For what it's worth, the Flight Capsule 3 (backup) lander body in Seattle's Museum of Flight has stenciling from Martin Marietta on sidebeam 2 which includes the notation "P/X 837K0100000-009" (as well as "S/N 0000003"). This suggests that the FC3 body is of variant type -009; perhaps the two Flight bodies FC1 and FC2 are also this type?

According to the set's revision history information, the initial release of the prints was on 27 June 1972. The revisions incorporated into this set occurred during the interval from 7 March 1973 to 15 January 1975 -- just seven months prior to launch of Viking 1. The last few revisions are mostly re-labeling of part-numbers or changes to fasteners. (Assembly of the Flight landers had been largely completed by late 1974.)

The lander body components are assigned Martin Marietta part numbers generally of the form 837J310xxxx-yyy, where xxxx identifies the component and yyy identifies a specific variant. For example 837J3100053-001 is the Surface Sampler's main mount (which happens to only come in one variant). The drawings often do not identify a specific variant in overview contexts, but all components have a formal variant tag. Sheet 1's parts-list pages include a group for each of the five lander variants (e.g., pages 9.001 to 9.021 contain the parts list for variant 9; pages 19.001 to 19.017 list parts for variant 19). I have collated all parts-lists pages into a spreadsheet showing which component variant belongs to which body variant(s). The spreadsheet also enumerates the drawing sheet(s) on which the given component is notably visible.

Scan Process

My paper copies of the drawing sheets are printed on C-size (17 x 22 inch) sheets, reduced from the master E-size (34 x 44 inch) sheets. The reduction is by a bit over 50%; Martin Marietta's reduction-copy process was a bit casual, yielding some skewed orientations accommodated by wide margins. I suspect this print set came from two different master original printings, because some sheet images are slightly larger with different borders than others. I have rectified the scans to be squared to the image area and of uniform size. I scanned the paper sheets at 600 DPI, which yields an image of about 120 million pixels (nearly 13K by 10K pixels). Google's PicasaWeb service currently allows a maximum image size of 50M pixels, therefore the album contains 300 DPI versions. Each sheet's image caption includes a link to a full-resolution version on DropBox.

A few of the drawing sheets are fairly clear prints, but most have extensive background mottling introduced in Martin Marietta's copy/print process. I have begun digitally cleaning the scans. In order to avoid loss of faint and obscured detail this is largely a manual masking job, which is very tedious. To date I have completed masking the first three drawing sheets (numbers 2, 3, 4). I hope to occasionally replace others with cleaned versions. A few of the sheets have annotations applied by a prior owner of the set. I will be removing such annotations during masking.

Lander Body Size

All linear dimensions are in inches and are usually specified to thousandths. These blueprints confirmed my earlier suspicion that the hexagonal body's long and short side lengths of 43 and 22 inches as stated in some NASA documents are incorrect. The long side length is approximately 43.359 inches; the published figure probably resulted from a simple rounding. However, the short side actual length is approximately 24.566 inches, which is about 10% larger than the published value. The height of the core body (excluding top and bottom covers and some integrally-machined protrusions) is exactly 18.000 inches, which agrees with the published value.

By the way the odd values for the side lengths are not direct design parameters. They are derived from the actual design parameters which are the distances from the body geometric center to the perpendicular midpoints of the sides. The design distance from the body center to the midpoint of a long side is specified as exactly 26.700 inches. From body center to midpoint of a short side is specified as exactly 32.125 inches. Application of some mathematics yields the side length values listed above. (I was pleased to discover that length estimates I had made earlier, based on known Aeroshell data, a scale USGS drawing of the lander, and knowledge of the nine-point interface between Aeroshell and lander, were only off by a few hundredths of an inch.)

The core lander hexagonal body consists of three (3) sidebeams, each machined from a single piece of aluminum. The three sidebeams are broadly similar but differ in numerous details (flanges, holes, stiffeners, etc.). The sidebeams are spliced or butted together with the vertical joints on the centerlines of the three landing legs. Therefore each sidebeam represents one complete long side and the halves of two adjacent short sides (appearing as angled short "wings" seen from above). Here is a rendering I've created of sidebeam 1.

Blueprint Notations

Each of the drawing sheets has a border dividing the sheet into an 8 by 8 grid of 64 zones. Zone coordinates range from 1 to 8 (bottom to top) and A to H (right to left). One portion of a drawing will frequently refer to another view or section on the same or a different sheet. Such zone references are denoted by a square containing number / letter coordinates, with a small sheet-number outside the upper right corner.


Large circles with multi-line text generally represent part numbers (e.g., 837J3101042-009) or fastener types (e.g., ST25D40-5-3).


Small circles containing a dash and three digits denote a simple flat shim part (of which the lander contains dozens). Sometimes the circle is omitted. The three-digit number is the variant tag for the shim's part number, all of which belong to the overall lander part number 837J3100000. For example, a notation of "-075" refers to shim 837J3100000-075. The parts-list pages show the shim's nominal sizes, with width and height larger than final to allow for trimming tolerances. The drawing sheets generally show the final shim sizes (which I've listed in the above spreadsheet when known).


Horizontal triangles containing a number are flags which reference one of the notes listed on pages 2.001 to 2.003 of sheet 1. Such notes detail process operations, assembly instructions, etc.


Small rectangles define construction reference planes, or specify tolerances in relation to a reference plane or point. In the following example the lower rectangle defines the associated feature (not seen in this fragment) to be Plane E. The upper rectangle specifies that this plane must be parallel ("||") to Plane A (defined elsewhere) within 0.020 inches.


A few features on the lander required a particular degree of machined surface finish. These are denoted with a stylized kind of letter J with an adjacent number (representing the roughness average value in microinches).


Anachronism

Most of sheet 18 is devoted to a prominent component which is not present on the final Flight-type lander bodies. It is an earlier design for the lander's Radar Altimeter Antenna mount (described in the parts list as "Support-LAA" and belonging to body variant 10). This photo of the Thermal Effects Test Model (TETM) has such a projecting assembly, visible at the right upper corner of the front of the inverted body (which corresponds to the lower left corner of sidebeam 2). This reinforces the idea that body variant -010 was used for the TETM, and that "TM" in the table I listed near the top of this write-up is the Thermal Model.