Introducing TeStaF, the technical standard for pilot's watches ... (additional material added)

[JohnF]

Hi -

No, it's not a new sponsor or a new watch brand, but rather something completely different.

I got up this morning at OhDarkHundred and drove some 350km to Donauwörth in Bavaria, where EuroCopter is located, the helicopter subsidiary (okay, they make other stuff as well) of EADS. There I met up with various others invited by the FH Aachen (Applied Sciences University of Aachen), Sinn and EuroCopter to launch a new certification process for Pilot watches: TeStaF.

It's a German acronym for Technischer Standard Fliegeruhren, the Technical Standard for Flying Watches. Now, I use the term Flying Watches rather than Pilot watch for a reason.

As all of us Pilot watch fans know, the vast majority of "pilot" watches out there are purely cosmetic, purely driven by marketing, rather than by technical aspects of the watch. There has been, to date, no accepted definition for pilot watches that is comparable to that of diver watches (which are defined as those watches meeting ISO 6425). Rather than taking the extremely laborious route of getting an ISO norm established - which would require approval by all manufacturers and everyone in the industry - the people behind the project decided to take a different route: providing certification for watches meeting the TeStaF norm.

The norm has been developed by the Flight Laboratory of the Faculty of Aerospace Technology of the FH Aaachen, together with Sinn Spezialuhren of Frankfurt to define what requirements have to be met to receive certification from TeStaF for a mechanical watch with analogue display, used for civilian flights operating under visual and instrument flight rules: it is a certification that has gone through a rigorous systematic analysis of aviation regulations (similar processes exist for flight instrumentation, for instance) and both a detailed survey of what real-world operating pilots in multiple aircraft categories say they want and need, as well as an exhaustive series of empirical application-oriented experiments. The first results of this new certification process were then reviewed and validated in a detailed field test.

In other words, any watch meeting the standards set up in TeStaF fulfill the real-world functional and physical requirements for time measurement devices in different aircraft categories. This is absolutely comparable to certifying an instrument panel component, for instance, or certifying various types of aircraft engines (okay, maybe not quite as extensive as the latter... )

This is the core of what the certification process defines (taken directly from TeStaF documentation:

In the event of simultaneous failure of the aircraft‘s timing instruments, or even a suspected failure, it is the purpose of the pilot‘s watch, as the primary time measurement instrument, to enable the pilot to plan and execute any necessary time-related flight manoeuvres, thereby providing a comprehensive substitute for the timing instruments installed or mandated in the aircraft.
The functioning of a pilot‘s watch shall not be affected by the physical stress of regular flying or by unexpected malfunctions of the aircraft. In all conditions its operation shall be simple and reliable and it shall be easily readable. It shall not present a potential risk for crew members, other instruments or the aircraft itself.

So what does that mean?

Without going into extensive detail - that will come in a few days - here is a basic list:

Wristwatch with 12 or 24 hour display with minutes; central seconds hand; stopwatch function for at least 30 minutes for instrument flight rules; central stopwatch seconds display, permanent seconds hand for function check, bezel rotatable in both directions with at least one marker for measuring time; hacking mechanism.

Further: time display, rotatable bezel and stopwatch function (if incorporated) must be readable in a rapid and unambiguous manner; daytime colors include black, white and any color except red (existing regulations assign special and clearly defined warning functions in aviation to the color red!); contrast between dial markings and background, hands and background, markings on bezel and bezel backgrounds must be at least 14:1 if not higher, measured as operating, i.e. with watch crystal; readability at night must include ability to read time and stopwatch function to an accuracy of at least five minutes or five seconds without manual activation of illumination or controls; lume must cover all hour indices, hour and minute hands, central second hand, five-minute markings of stopwatch minute indices, stopwatch minute and second hands, as well as at least one market on rotating bezel; no red lume; lume must serve also to clearly orient the dial under no illumination; lume must last at least three hours in complete darkness.

Further: rotatable bezel must have clearly perceptible minute ratcheting and operating elements for stopwatch functions must have a clear point of resistance to indicate activation; all controls must meet temperature requirements; all controls must be operable when wearing common aviator gloves.

Further: accuracy tests are to be taken in four positions (6 up, 9 up, dial up, case back up) and at the following temperatures: -15°C, 23°C and 55°C, with the watch fully wound. Minimum acceptable accuracy under these conditions is plus/minus 30 seconds/day; at 23° no less than 15s/day, with a power reserve of at least 36 hours, with the first three hours with active stopwatch function..

Water resistance according to DIN 8310, with this being rechecked after each of the following additional tests: watch must withstand a reduction in ambient pressure from 0.752 bar to 0.044 bar within 15 seconds, maintain integrity at 0.044 bar for no less than two hours; this test is to be repeated after a pause of one hour; watch will be subjected to a pressure change between 1.013 bar to 0.752 bar and back no less than 2000 times (this tests the integrity of the watch case to the usual pressurization of civilian aircraft from surface to operating altitude); manufacturer must state operative temperature range, which must be at least between -15°C to +55°C; the watch must also be able to go from the minimum temperature to the maximum within 5 minutes in both directions.

The watch must be able to withstand 6g of acceleration in four positions for one minute each (i.e. not a short test, but rather the watch must operate and continue to operate while under these conditions!); further, the watch must also withstand uniformly varying frequencies between 2Hz and 10Hz as well as between 30Hz and 60Hz with amplitude as defined in MIL-PRF-46374G;

In addition to water reistance according to DIN 8310/ISO 2281, the watch and individual parts must not be damaged by fuel, lubricants, solvents, cleaning agents and de-icing fluids.

There is no test for magnetic fields, as empirical field tests have shown that magnetic fields such as are used in civilian aircraft do not pose a danger to watches; however, a demagnetised watch must not influence a standard magnetic compass certified for use in aircraft when placed in 10mm distance by more than 2.5° deviation.

Further: anti-reflective coatings are a must, as are non-glare case components; readability of cockpit instruments must not be compromised by watch lume; protruding parts may not catch on or block aircraft functions; the strap must withstand a tensile force of 200 N without damage.




Whew.

What does this mean for the watch industry?

Well, first and foremost, they can apply for certification of their watches.

Second, obtaining certification means, at the very least, that you've got one serious watch.

Third: certification is for a designated design, with design variances approved, rather than for an individual watch. This keeps certification costs down and is how aviation equipment in general is certified for use.

Fourth: this is not an insurmountable process, but rather one that does require some solid work on the manufacturer's side. Certification includes protocols and variances, and TeStaF wants to work with manufacturers to help them get certification, i.e. this is a supportive role and process.

Fifith: while no one can effectively be stopped in telling folks that they make pilot watches, certification is the process where the wheat is separated from the chaff.



So, that's it in a nutshell. More to follow, but I gotta get some sleep.

PS: Goodness. Forgot the URL: FH Aachen: TeStaf-Projekt

[KOB.]

Further: rotatable bezel must have clearly perceptible minute ratcheting and operating elements for stopwatch functions must have a clear point of resistance to indicate activation; all controls must meet temperature requirements; all controls must be operable when wearing common aviator gloves.

Water resistance according to DIN 8310

The rotatable bezel would count out many of the 'pilot chronographs' and certainly the Nav-B type watches as would some of the WR requirements. I don't know much about DIN 8310, but I was under the impression that it had to pass this requirement to be classified a 'Dive Watch'. Nor do I suspect that the clocks in an aircraft have a WR rating to DIN 8310? So why would the instrument that replaces it require additional functionality. WR wouldn't be high on my list of requirements for a 'pilot watch'.

thereby providing a comprehensive substitute for the timing instruments installed or mandated in the aircraft.

It seems that you have a specification that exceeds the specification of device it replaces, but maybe someone else that is more knowledgeable than I can comment.

And your standard seems to rule out digital watches. Surely it is about functionality required and not how that functionality is achieved?

Of course, you can put whatever you like in the standard.....

Just a thought.

KB

[Drop of a Hat]

This is super cool.

Sent via Tapatalk

[Dark30]

That is very interesting, thanks for posting!

I am curious to see how a watch to these specs looks, if you ever have an image of something that qualifies if you could post it I'd appreciate it.

[drjmills]

If you go to the URL linked in the original message and look in the Gallery you'll see:

FH Aachen: Galerie

[Crusader]

John has done an excellent job summarizing the TeStaF project. As the freelance project co-ordinator for the TeStaF project (the final phase of which which caused my absence from the forum for the past few months) I am going to add a few details in this thread.

Firstly, it has been announced at Eurocopter by Professor Janser of the Aachen University of Applied Sciences that two watches, a Sinn 103 and the Sinn EZM 10, passed the tests and will be issued the first certificates. Pictures will be relased by Sinn shortly, I expect.

Secondly, here is the official English Sinn announcement of the project:

Technical Standard for Pilot's Watches
Technischer Standard Fliegeruhren
(TeStaF)


Summary:
The Department of Aerospace Engineering of the FH Aachen – University of Applied Sciences and Sinn Spezialuhren have jointly developed a technical standard for pilot's watches (Technischer Standard Fliegeruhren, or in short, TeStaF). Comparable to the standard for diver's watches (DIN 8306 / ISO 6425) it gives the assurance that a pilot's watch meets all current requirements for time measuring instruments when piloting an aircraft.

Background:
„Pilot's watches“ were the principal timekeepers during the rapid development of flight in the 20th century. Today they are still the primary time measuring instrument in some prototypes, and in aerobatic and historical airplanes, and they continue to serve as back-up systems in other aircraft.

But what does constitute a professional "pilot's watch"? How is it put to use by a pilot in flight? Which features are indispensable? So far, there has never been an accepted definition for pilot's watches comparable to that for diver's watches (DIN 8306 / ISO 6425).

The Project:
As early as 2008 Sinn Spezialuhren took the initiative to tackle this research project and fill the gap. In order to bring the TeStaF to life, it was crucial to bring together the expert knowledge and the experts of a number of disciplines. In a joint project, the Department of Aerospace Engineering of the FH Aachen – University of Applied Sciences and Sinn Spezialuhren with the help of many external experts developed the "Technischer Standard Fliegeruhren" (TeStaF), the technical standard for pilot's watches. The TeStaF will be presented to the public at the facilities of Eurocopter Deutschland, the leading manufacturer of helicopters and an important contributor to the project, on 19 July 2012.

The goal was the creation of an unambiguous, technical-functional catalog detailing which requirements pilot's wristwatches with analog time display must meet today in civil aviation under Visual and Instrument Flight Rules.

• A detailed survey of pilots of many different aircraft categories provided information on their functional and practical timing requirements in flight.

• A comprehensive series of experiments and measurements was conducted in the laboratories of the Department of Aerospace Engineering of the FH Aachen – University of Applied Sciences as well as on several airplanes and helicopters concerning the physical challenges of flight operations.

• Current and historical horological and aviation-related standards were surveyed and reviewed with a view to their applicability for the TeStaF.

• Finally the results gathered were subjected to a detailed field-test spanning several weeks in the course of the prototype testing of a Eurocopter helicopter – and confirmed.

The Result:
A wristwatch which meets the "Technical Standard for Pilot's Watches" offers the assurance that it fulfills the relevant functional and physical requirements for time measurement devices in aircraft.

An overview of the key TeStaF requirements (abbreviated):

1 Functionality
 Required functions for Visual and for Instrument Flight Rules
 Readability in daylight and at night
 Safe operability
 Accuracy and power reserve

2 Resistance to External Stress
 Absolute and cyclically changing ambient pressure
 Operative temperature range and rapid temperature change
 Shock and impact resistance, G-forces and vibrations
 Resistance to water pressure and common aviation fluids
 Effects of magnetic fields on the watch

3 Safety and Compatibility
 Magnetic signature effects of the watch on the avionic suite
 Prevention of reflections and glare
 Form
 Secure strap fastening

Tests and Certification Process:
The FH Aachen – University of Applied Sciences has developed a rigorous test regime for the TeStaF. As part of the technology transfer program by the Aachen Institute of Applied Sciences e.V. (AcIAS) it is offered to all watch manufacturers.

If tested successfully, the fulfillment of the TeStaF requirements by pilot's watches is recorded in a certificate analogous to the certification of the U-series watches by the Germanischer Lloyd. Only certified watches may carry the word "TeStaF" and/or the TeStaF logo on the case and/or the dial.

The Way Ahead for the TeStaF:
From the very beginning the project partners aimed at creating a universal standard available to all watch manufacturers. Accordingly, the TeStaF is freely available as a scientific publication in both German and English

Continuing development of the TeStaF in order to reflect progressing aviation requirements is planned. For this purpose a scientific advisory committee of experts has been established. Suggestions for the further development of the TeStaF by users or by the industry are most welcome.


Additional information are available at FH Aachen: TeStaf-Projekt [the website is in German, but the TeStaF standard can be downloaded in an English version there]

So where's the beef?
- low-pressure resistance tested in a 2,000-cycle pressure change to imitate the stress a watch is exposed to on the wrist of a professional pilot.
- for the first time in aviation watches, the detrimental effect of a watch's magnetic field on the avionics (especially the emergency compass) is being taken into considerations.
- resistance against typical aviation fluids (fuel, lubricants, cleaning and de-icing agents) complements basic water-resistance
- No special or proprietary technologies are needed to obtain certification

Thirdly, a good number of members of this forum were involved in the project: many pilots partcipated in the initial "critical Flight Timing Requirements Survey", and others contributed with their expertise (like e.g. Colin a.k.a. Nalu). The project is indebted to all of them.

[tribe125]

Hmm... it seems churlish to question an in-depth development programme, but why no quartz - for a standard that is presumably intended to be appropriate for industry-wide application?

[Mike Weinberg]

Hmm... it seems churlish to question an in-depth development programme, but why no quartz - for a standard that is presumably intended to be appropriate for industry-wide application?

It looks very much as if this project was suggested to begin with by Lothar Schmidt, because Sinn doesn't make any quartz pilot watches. Any number of Casios could meet these specs.

[Andrew McGregor]

Nothing in the standard appears to prevent a quartz watch from passing. However, the low temperature limit will be HARD to do with a quartz watch. I expect a Spring Drive would have no difficulty.

[JohnF]

Hmm... it seems churlish to question an in-depth development programme, but why no quartz - for a standard that is presumably intended to be appropriate for industry-wide application?

I think there are several reasons. Consider as well that this is a standard designed for analogue display watches, not digital. That would be covered, I think, by either extending this or creating a second standard. Nothing to prevent them from doing that.

However, I think that the standard is one for a designated piece of mission-capable aerospace equipment (hence the certification process) that serves primarily as a backup to mounted cockpit watches. When we were at EuroCopter during the facility tour, there were two mockups of cockpit displays for a certain type of helicopter. The one display was the old standard analogue display cockpit (slang term: watch store, Uhrenladen), the other was the so-called glass cockpit with electronic displays (slang: mouse movie theater, Mäusekino). On the glass cockpit side of things, there was no analogue backup clock whatsoever: hence TeStaF is the only independent time display unit within a glass cockpit (at least that one), and given the inevitable risks, no matter how small, of a watch battery failing and turning the watch into a deadweight, the mechanical nature of the standard makes sense to me.

JohnF