Shattering the Speedy Hesalite Apollo / NASA selection myth (maybe)

[Omegafanman]

SpeedyPhill

@Omegafanman wrote: Omega have a treasure trove of documentation...Maybe so but IMHO what they have been doing with it the last couple of years leaves much to be desired, but I won't go into details as this has been pointed out in other topics...

Hi @SpeedyPhill. As a newbie I have not picked up on a lot of the old threads. I am more than interested to understand your thoughts better. Would you please post some links or spell it out a bit more? (Also when it comes to reading between the lines I am the guy asking do you want fries with that :0)

 

[Omegafanman]

Omegafanman

Thanks - I will watch it shortly - appreciate the link.

Thanks again - I enjoyed that and picked up some new information. The undiagnosed failure mode of that LEM window was frightening. Also shows the risk they were taking when not in pressure suits. With such a small space and no bulkheads they would loose air fast. We recommend that you keep your seatbelt fastened at all times …:0)

 

[Omegafanman]

Extra information and a cross over with Space sponsorship (maybe)
Just as a foot note. I found a nicer more humanised version of the Apollo 15 instrument glass failure documented from an Australian relay station (copied below). I have noticed there seems to be a lack of information and mission crew photos for Apollo 15 from NASA. I know public interest was waning but is this lack of mission information also related to the postal covers incident... I was vaguely aware of it but not that it led to the suspension of 15 astronauts who were deemed to have ''broken faith with NASA''. Similarly the copies of the fallen astronaut caused some scandal as well. It looks like mission 15 really opened the floodgates for Space sponsorship and the value of 'flown' items.

Instrument break transcript….During their evening, at 0930 AEST, Scott and Irwin decided to enter the LM fifty minutes early to check it out, but when they opened the hatch they found the cabin had broken bits of glass floating around. It was from the face of a lunar landing range and range-rate tapemeter. This was dangerous as the tiny shards of glass could cause damage to the eyes or lungs, but there was also the worry the tapemeter may have been affected, as it was a critical instrument for their landing on the lunar surface. A tapemeter is a meter which displays its reading with a moving length of tape that unreels rather than a pointer or digital display.They promptly shut the hatch to stop any particles drifting into the Command Module and switched the LM’s air conditioner on, hoping to draw all the floating pieces to the exhaust screen where they could mop them up with adhesive tape wrapped around their hands. During the checkout good voice and data communications were established through Goldstone, and a successful TV transmission showing views of the Command Module and LM interior was completed. Later they tried using a vacuum cleaner from the CSM to suck glass particles from crevices and crannies. At Houston the engineers worked on the tapemeter to see if its operation had been affected, but it seemed to be working okay. Scott admitted, “That gave me a warm feeling to know that they checked the thing out and it would work with a broken outer pane of glass.”During the ‘late afternoon,’ at 1734 spacecraft time (0834 AEST), Scott and Irwin checked out the LM for about two hours, and collected about 60% of the broken glass. Everything checked out to specifications, including the tapemeter.

Edited: Mar 20, 2019

 

[snake.doctor]

Thank you very much for your research and all the informations listed !

 

[robinhook]

Fantastic post! This is like watching a documentary.

 

[jimmyd13]

Omegafanman

Another relevant item which I have limited information on are the super cool USAF approved American Optical pilot sunglasses ‘flight goggle’ issued to all the crews (pictured). I think these had glass lenses (any clarification gratefully received)

Here are an original pair of American Optical Pilot's from c.1943.

The lenses are glass ... trust me ... I've spent hours polishing the damn things by hand to remove old scratches and I've still not got them all. AO were making the first UV blocking and polarising lenses from the early 30s. The lenses were all glass.

 

[TLIGuy]

Omegafanman

Thanks again - I enjoyed that and picked up some new information.

If you enjoyed the Lunar Module documentary you would enjoy the others in the series. They are all fantastic and give a great historical background on the engineering and development of the major Apollo components.

Saturn 5 Rocket

The Lunar Rover

Apollo Command Module

Apollo Space Suit

Apollo DSKY Navigation Computer

 

[SpeedyPhill]

@Omegafanman
Let's recount as it all started with the disappearance of the very nice & correct straight writing caseback as NASA only approved the "Flight-Qualified by NASA" caseback in 1971... still correct but the advertizing mentioned The first and only watch worn on the Moon, a text that later even appeared on the edge of the display caseback of 2002...
For the rest... The forum has a search function

 

[Omegafanman]

TLIGuy

If you enjoyed the Lunar Module documentary you would enjoy the others in the series. They are all fantastic and give a great historical background on the engineering and development of the major Apollo components.

Saturn 5 Rocket

The Lunar Rover

Apollo Command Module

Apollo Space Suit

Apollo DSKY Navigation Computer

Thanks … I will follow up on those. By way of exchange if anyone has an Ipad this runs as a replica DSKY. I have had some fun playing with it and it shows why wrist watches were important backup back in the day :0)

https://itunes.apple.com/gb/app/dsky/id567387896?mt=8

Dsky is the Apollo Guidance Computer DSKY simulator for iPad.
Dsky simulates the look and feel of the original Apollo DSKY keyboard and user interface

 

[Omegafanman]

robinhook

Fantastic post! This is like watching a documentary.

Thanks …. More like Forensic files without Peter Thomas or a conclusion.... gonna need more than a bucket of Luminol to solve some of these cases...….

 

[Omegafanman]

jimmyd13

Here are an original pair of American Optical Pilot's from c.1943.

The lenses are glass ... trust me ... I've spent hours polishing the damn things by hand to remove old scratches and I've still not got them all. AO were making the first UV blocking and polarising lenses from the early 30s. The lenses were all glass.

Thanks for the post, extra info and picture @jimmyd13. Great shades / quality sure lasts. I am very envious in a good way. For sunglasses I now know celluloid came in from the late twenties and from the late forties I believe more modern style plastic lenses came in. For sure glass gives better optical performance and scratch resistance. As previously mentioned it was 1972 before the FDA made shatter resistant lenses mandatory for eyeware and we have seen from 1973 that NASA was already using plastic lenses and was developing scratch proof coatings as a by product of unrelated experiments. I guess there is a balance between weight, shatter and fire risks plus overall performance. Glass and plastic can both be treated to block UV so one assumes (always dangerous) that performance in terms of UV protection can be made the same and even enhanced for use in space. Looking at all the available evidence and the dates I am still minded that the NASA moon googles probably (99%) had plastic lenses.... but I would like to be 100% sure..

 

[Texas Toast]

Since there are some space/engineering fans here I'll hope a bit more of a sidebar on the Apollo 15 meter and glass-in-space topics might be interesting.

At the 30-day mark, A15's meter glass breakage was thought to be related to torque-stress from badly shimmed instrument mounts per section 3.8 in https://www.lpi.usra.edu/lunar/ALSEP/pdf/30-dayFailure_AnomalyListing.pdf

The final A15 Anomaly Report, excerpted below, zeroed in on (annealed soda-lime) glass surface flaws and describes glass-fortifying fixes implemented post-mission.

Sub-sidebar: A Range/Rate ground test instrument intentionally broken to simulate the Apollo 15 situation for evaluation has been auctioned a couple times - I was always bummed I didn't pick it up in 2008:

Source: http://images.goldbergauctions.com/php/lot_auc.php?site=1&sale=49&lot=144&lang=1
See also https://www.rrauction.com/PastAuctionItem/3275436

Glass persisted from early Shuttle analog instrumentation (some borrowed from Apollo) to later "Glass Cockpit" upgrades https://www.aviationtoday.com/1999/11/01/the-space-shuttle-modernized/ where added cover sheets - like the Apollo fixes - are used to guard against glass breakage and/or dispersement of fragments. Don't know if the Glass Cockpit upgrades involved purged/sealed instrument assemblies where a pressure differential could exist, as was the case for the A15 Range/Rate meter in the LM. I can say a lot of glass could still be found in the cockpit of the final 2011 Shuttle flight.

Keen to learn any contrary data of course, but all of this suggests to me the acrylic Speedmaster crystal selection had little/nothing to do with any kind of NASA prohibition on glass materials in space craft.


Source: https://spaceflight.nasa.gov/gallery/images/shuttle/sts-101/hires/jsc2000e10522.jpg

----
From the Apollo 15 Mission Report: https://www.hq.nasa.gov/alsj/a15/a15mr-14.htm
14.2.8 Broken Range/Range Rate Meter Window

Sometime prior to ingress into the lunar module, the window of the range/range-rate meter broke ( fig. 14-34). Upon ingress, the crew saw many glass particles floating in the spacecraft, presenting a hazardous situation.

The window is an integral part of the meter case and is made of annealed soda-lime glass 0.085-inch thick. The meter case is hermetically sealed and pressurized with helium to 14.7 psia at ambient temperature. At the maximum meter operating temperature and with the cabin at vacuum, the pressure differential can be as high as 16.1 psi. This pressure differential is equivalent to a stress level of 6680 psi in the glass.

Glass will break when there is a surface flaw large enough to grow at the stress levels present. The threshold flaw size in a dry environment is about the same as the critical flaw size and immediate breakage occurs. The critical flaw size remains the same in a humid environment, but the threshold flaw is much smaller. For annealed soda-lime glass at a stress level of 6680 psi, the critical flaw depth is 0.0036 inch, and for a humid environment, the threshold flaw depth is 0.000105 inch.

A surface flaw deeper than the threshold depth for the glass operating stress must have existed on the outside of the meter window at launch. The flaw started growing as the cabin depressurized during the launch phase, and finally grew large enough for the glass to break.

For future missions, an exterior glass doubler will be added to the flaw depth to 0.0036 inch and the critical flaw depth to 0.032 inch. This should prevent future fatigue failures since there are no reported fatigue failures in soda-lime glass at stresses below 2000 psi. In addition, all similar glass applications in the lunar module and command module were reviewed and changes are being made. In the command module, transparent Teflon shields will be installed on the:

a. Flight director attitude indicators.
b. Service propulsion system gimbal position and launch vehicle propellant tank pressure indicator.
c. Service propulsion system oxidizer unbalance indicator, and the oxidizer and fuel quantity indicators.
d. Entry monitor system roll indicator.In the first three above applications, the shields will be held in place with Velcro and will be installed only when the cabin is to be depressurized. The shield on the entry roll monitor indicator will be permanently installed\\

In the lunar module, tape will be added to the flight director attitude indicators and an exterior glass shield will be installed over the crosspointers to retain glass particles. The data entry and display assembly window was previously taped to retain glass particles.

 

[Omegafanman]

@Texas Toast - Many thanks for posting this information and the links. I think that subject to any other data ''and the acrylic Speedmaster crystal selection had little/nothing to do with any kind of NASA prohibition on glass materials in space craft'' is the only logical conclusion to make. I have downloaded the 30 day failure report for a read later. I think we all share your pain for missing out on that test instrument...Thanks again for the solid info.

 

[cvalue13]

Elsewhere there’s been posted the original NASA “Statement of Specifications” for the wristwatches to be used by NASA astronauts, which did in fact give treatment to the issue of having a “shatterproof” crystal.

While the specifications do not use the word “plexi” (etc.), I think it reasonable to assume that “shatterproof” had straightforward colloquial meaning amongst the engineers that wrote the Statement of Specifications.

Still today it looks like the materials selections prerogatives for both NASA and ISS deal with the topic in a rather pragmatic way: avoid frangible materials when you can, and when you can’t minimize risk.

In all, it seems that the “Statement of Specifications” specifically contemplated a crystal that was “shatterproof,” which meant on this metric the Speedmaster qualified at all (compared to possible competitors that used sapphire at the time). Engineers are far too specific to specify “plexi” if the quality they actually desire is more fundamental, being open to whatever material may satisfy the more fundamental requirement of being “shatterproof.”

These pragmatic materials selections for avoiding frangible materials can still be seen being discussed at length today for the various types of frangible materials used in craft or on ISS

From NASA, a white paper:

SAFELY CONTAINING FRANGIBLE MATERIALS USED IN SPACE FLIGHT EQUIPMENT


From ISS:

ISS Safety Requirements Document section titled “Shatterable Materials”

“SHATTERABLE MATERIALS
Shatterable materials are unique physical agents. A shatterable material is any material that can fracture under a load or impact and produce fragments that are potentially hazardous to the crew and/or vehicle. Common shatterable materials on the ISS include glass, ceramics, LCD monitors, certain metallic alloys, optical equipment, and any other frangible materials that can fracture and produce fragments. Shatterable material requirements are addressed based on preventing release of fragments (Section 4.7.2.5.2.1, Shatterable Material Release) and based on protecting optical glass from fracture (Section 4.7.2.5.2.2, Optical Glass Protection).

This section addresses potential IVA release of shatterable materials. Shatterable materials that do not fit into the requirements below should meet structural requirements as addressed in Section 4.2, Structures.

SHATTERABLE MATERIALS RELEASE
End items with shatterable materials shall prevent the release of fragments larger than
50 micrometers (μm) into the ISS habitable volume.
Rationale
This requirement encompasses shatterable materials that are located in or may be introduced into the pressurized habitable environment. It is established to protect the crew from physiological hazards and/or to protect the environment and VV/ISS equipment from hazards resulting from contamination.
Additional rationale for this requirement can be found in Appendix D.4.7.2.5.2.1.
4.7.2.5.2.1.1 VERIFICATION– SHATTERABLE MATERIALS RELEASE
Verification is considered successful when one of the following is completed: A or B
A. The end item design is shown to fully and permanently contain the shatterable
material, based on both of the following.
1. The contained covering is identified and proven effective in preventing
shatterable material release. (A or T)
2. Review of the end item design and review of the as-built hardware shows containment of the shatterable material. (I)
B. When containment is not practical, the following are provided:
1. For non-operational phases (launch or when hardware is not operational),
both of the following are provided: (1 and 2)
a. The contained covering is identified and proven effective in preventing shatterable material release. (A or T)
b. Review of the end item design and review of the as-built hardware shows containment of the shatterable material. (I)
2. For the operational phase, the following is provided:
a. Inspection of procedures shows that operational controls are in place to inspect for breakage prior to removing the protective covering, restoring the protective cover when not in use, and identification of any limitations in the use of the end item that prevent damage to the shatterable material.”

Edited: Apr 10, 2022

 

[cvalue13]

Texas Toast

but all of this suggests to me the acrylic Speedmaster crystal selection had little/nothing to do with any kind of NASA prohibition on glass materials in space craft.

not that there’s a prohibition, but instead a pragmatic approach to materials selection that attempts to avoid frangible materials when possible, or to when not possible to minimize risk from those materials.

so when it came to watches, if there existed two more or less frangible options for the crystal, then all else equal in terms of performance and risk, the materials selection would have quite straightforwardly selected for the less frangible option - regardless of whether other equipment on board may have been more frangible for some other reasons.

which again, means not that NASA selected the speedmaster because of its hesalite crystal, but instead that the speedy with a hesalite crystal qualified to be considered in part because it happened to have a hesalite crystal.

I can’t say off hand that there were chronographs with sapphire crystals at the time, but there had for decades existed “sports” watches with sapphire crystals (eg the JLC reverso) - which the specifications were selecting against.

 

[Omegafanman]

@cvalue13 Interesting information above which I consider as follows in terms of the original Moonwatch question. I also note the specifications are all more recent and I have not tracked down anything from the sixties or seventies yet which reflects that wording.

On any large complex structures there will be multiple specifications (oil rigs, ships, aircraft etc). I have seen many examples were these become contradictory. They can also be relaxed or ignored subject to a risk assessment to allow for specialist equipment (sometimes by differentiating the structural specifications). It would be pointless and very expensive to apply all Lloyds register specifications to be ice cream machine on an ocean liner. There is also the risk/benefit consideration. Is a shatterproof material less fire resistant for example.
I have still not seen any evidence of a shatterproof requirement, specification or test being applied to the NASA watches in the sixties or seventies. Glass was also clearly being used for instruments etc in Apollo and the shuttle.
Sapphire glass was available in the sixties but I do not know how many chronograph watches in the price range would have been around with anything other than plastic crystals when they made the equipment selection. As sapphire glass has become the de facto high end watch crystal there has been nothing to preclude or prevent there use in space (the X33 being the obvious example). Many personal preference watches have also flown with Sapphire crystals (I don’t know the spec of the Panerai which was recently used on a space walk?)
Of course the shape and design of crystal will make some less prone to breakage, but I have not seen or heard of any qualification tests to check those for flight approval. COTS parts are being used more and more in space flight to reduce unnecessary costs. The Speedmaster was unmodified and commercial off the shelf. I still do not think on all known data the crystal material was or is part of the selection criteria and it is not reviewed to to same standards as the structural design.
.

 

[hen]

Its just a myth to make you pay top dollar for a second rate crystal.

 

[cvalue13]

Omegafanman

I also note the specifications are all more recent and I have not tracked down anything from the sixties or seventies yet which reflects that wording.

In case I’m misunderstanding: the “Statement of Specifications” I posted first that mention the requirement of a “shatterproof crystal,” we’re the specs sent by NASA to the manufacturers prior to the testing and selection of the Speedmaster.

A few folks here have pdf copies of the memorandum that contains the statement of specs.

 

[Omegafanman]

cvalue13

In case I’m misunderstanding: the “Statement of Specifications” I posted first that mention the requirement of a “shatterproof crystal,” we’re the specs sent by NASA to the manufacturers prior to the testing and selection of the Speedmaster.

A few folks here have pdf copies of the memorandum that contains the statement of specs.

I think they just bought the watches off the shelf for the tests and an official order was placed after the testing and selection process.
@SpeedyPhill or @TLIGuy might be able to elaborate. It would also be good to see a pdf of the original specification from the sixties if someone one is able to post that up.

 

[Omegafanman]

A bit of thread drift but this has also got me wondering if they did anything special for the cameras…. Another instrument with a lot of glass which gets waived around.

Some of the items found after Neil Armstrong died also look like they had glass elements ..
https://www.hq.nasa.gov/alsj/a11/a11ReturnedEagleArtifacts.html#8
.

Edited: Apr 11, 2022