Sinn Model 103 Ti UTC TESTAF

Model 103 Ti UTC TESTAF

The traditional pilot’s chronograph.

• Tested and certified to the Technical Standard for Pilot’s Watches (TESTAF) by the Aachen University of Applied Sciences
• Second time zone on a 12-hour basis
• Case made of titanium, bead-blasted
• Ar-Dehumidifying Technology enhances functional reliability and freedom from fogging
• Functionally reliable from –45°C up to +80°C
• Captive pilot’s bezel with minute ratcheting
• Sapphire crystal glass
• Transparent back made of sapphire crystal glass
• Pressure-resistant to 20 bar (= 200 m water depth)
• Low pressure resistant

TESTAF – For the first time, a standard for pilot watches for professional use is defined.

TESTAF – a completely new departure

What are the distinguishing features of a professional pilot’s watch? Which aviation requirements does it need to fulfil? Which features are indispensable? To provide universally valid answers to these questions it was necessary to formulate a norm or standard. Such a standard did not, however, exist for pilot’s watches at that time. And so in 2008 Lothar Schmidt (Dipl.-Ing.), managing director and owner of Sinn Spezialuhren, seized the initiative and decided to close this research gap together with Prof. Dr.-Ing Frank Janser of the Aachen University of Applied Sciences, for years now one of the most respected centres for aerospace technology (the mechanical engineering faculty, to which the aerospace technology department belongs, topped the 2012 university rankings). With its long tradition of developing and testing aerospace instrumentation, the Aachen University of Applied Sciences uniquely combines a strong practical orientation with profound scientific knowledge and flight engineering expertise. The faculty is one of the few in Germany to own its own aircraft; it uses these for teaching, flight laboratory and research purposes. The Aachen University of Applied Sciences is one of the leading teaching and research institutions in Europe in the field of aviation.

Technical progress in watches

The collaboration with the Aachen-based aerospace engineers permitted a number of technical advances in watchmaking to be applied for the first time. Under TESTAF, for example, the low pressure resistance of the watches must be tested more than once. Indeed, they are subjected to several thousand pressure change cycles in order to simulate the actual stress conditions on the wrist of a pilot. Besides being water resistant, a pilot’s watch must also be resistant to common aviation fluids such as fuels, hydraulic fluids and cleaning and de-icing agents. In addition, the magnetic field of the pilot’s watch itself must not interfere with the avionics such as the aircraft’s emergency compass. A further safety aspect is that a pilot’s watchmust not dazzle the pilot and must be largely free of reflections.

Specifications

The aim of the project was to draw up a clear catalogue of technical and functional specifications which precisely describe the time measurement requirements during flight in the following categories:

1. Functionality

• Required functions during flights operating under visual and instrument flight rules
• Readability in daylight and in darkness
• Good operability
• Accuracy and power reserve

2. Resistance to external stress

• Absolute and cyclical ambient pressure changes
• Operative temperature range and rapid temperature change
• Shock and impact resistance, G-forces and vibration
• Resistance to water and other aviation fluids
• Effects of magnetic fields on the watch

3. Safety and compatibility with other instruments

• Effects of the watch’s magnetic signature on avionics
• Avoidance of reflections and dazzle
• Appropriate form
• Secure strap fastening

 

Published by WatchMundi