The advent of aviation at the start of the 20th century gave way to a whole new genre of watch: the pilot’s watch. Some models feature additional functions you won’t find on everyday watches. Find out more about these unusual features and whether these watches make worthwhile purchases.
What distinguishes a pilot’s watch from other timepieces?
Pilot’s watches came to be as a result of early pilots needing a way to tell time without taking their hands off the flight controls. The simplest solution was to mount a pocket watch on a strap they could wear around their wrist. Watches like the Cartier Santos from 1904 were a sensation in the heyday of the pocket watch, ushering in the era of the wristwatch.
But the strap isn’t the only factor that has maintained the popularity of pilot’s watches. These timepieces are considered robust, reliable, and highly-functional tool watches. They often feature streamlined, minimalist dials with contrasting dark backgrounds and light numerals, hands, and indices, making them readable in varied lighting conditions.
Over the years, watch manufacturers have added a number of new functions to pilot’s watches. Some of the more useful additions include chronograph complications, which can aid pilots in navigation. Likewise, many feature a GMT function, which displays the time in multiple time zones. Others still are equipped with rotating countdown bezels, which allow pilots to keep an eye on different time intervals.
In addition to the more common functions mentioned above, some pilot’s watches boast more unique features. Let’s take a look at some of the more unusual functions on the market.
Watches With Altimeters and Compasses
You’d be hard pressed to find a cockpit without an altimeter. It tells pilots their current altitude as well as whether the aircraft is ascending or descending. This is obviously essential information during flights with poor visibility. Several timepieces are also equipped with this feature. Most manufacturers have turned to electronic measuring instruments, such as the watches in Tissot’s T-Touch line. However, others have created fully mechanical altimeters. Such is the case with Swiss manufacturer Oris’ Big Crown Altimeter. This watch has a small metal capsule within it that is similar to the kind found in an aneroid barometer. The capsule reacts to changes in air pressure and expands or contracts accordingly. This movement is then transferred to a needle that displays the pressure and corresponding height on a scale.
No aircraft is complete without a compass. If the dash compass fails to work, however, it is relatively easy to determine direction using an analog clock. In the Northern Hemisphere, simply point the hour hand toward the sun and halve the space between the hour hand and 12 to find due south. In the Southern Hemisphere, you can follow the same procedure to find due north. Watches like the Breitling Cockpit B50 or the Citizen Promaster Altichron are equipped with special compass bezels for this express purpose. In addition to the four cardinal directions, they also feature graduation, transforming your average pilot’s watch into a full-fledged navigational tool.
Slide Rule and Drift Angle
Before computers made their way into cockpits, pilots had to manually calculate their course, fuel consumption, rates of descent and climb, and flight path deviations. This was done using a slide rule for multiplication and division as well as figuring squares and square roots and solving logarithmic and trigonometric equations.
Manufacturers experimented with adding a slide rule to pilot’s watches early on. Breitling developed a watch with an integrated slide rule in 1942: the Chronomat. Ten years later, the traditional Swiss company presented the first Navitimer, which would go on to become a major hit. The pilot’s chronograph features a characteristic slide rule bezel and remains one of the most popular Breitling models to this day. It is an absolute must-have in any pilot’s watch collection. If you can do without a chronograph function, the Seiko ProSpex Automatic Aviation SRPB61J1 is a more affordable alternative.
Another piece of vital flying information is the impact of crosswinds and air currents on a flight path. Pilots must calculate what’s called the drift angle in order to take the appropriate course of action. In modern aircraft, computers usually complete this task; however, glider and recreational pilots don’t always have sophisticated equipment and must be able to calculate it by hand. Watches like the Hamilton Khaki Aviation X-Wind can be of great assistance in these situations. They are outfitted with a special slide rule bezel that is designed to calculate drift angle.
Charles Lindbergh and the Hour Angle Watch
One of the earliest pilot-specific complications was developed at Longines. In 1927, the Swiss manufacturer partnered with American navigation specialist and aviation pioneer Philip Van Horn Weems to created the so-called Weems Second Setting Watch. The timepiece features a rotating disc in the center of the dial that can be synchronized with a time signal. The watch went on to inspire the development of the famous Longines Lindbergh Hour Angle watch in 1931 and still remains a cornerstone of the Longines portfolio to this day.
In 1927, Charles Lindbergh approached Longines in the aftermath of his historic transatlantic flight. He wanted to develop a watch that pilots could use to calculate their current position over the open sea – thus, the Hour Angle watch was born. Together with a sextant and astronomical tables, navigators were able to use the watch to determine their current longitude and latitude. The Lindbergh Hour Angle watch likewise remains a part of the Longines catalog.
Are pilot’s watches worth it?
If you’re wondering when you’d ever need an altimeter, a compass, or a slide rule in this day and age, you have a fair point. Any modern smartphone could likely do any of those jobs more conveniently and accurately. Smartphones even take the cake when it comes to displaying the time. But does that mean watches are superfluous? Definitely not!
Watches with mechanical altimeters or a slide rule bezel may seem like a useless gimmick, but they are undoubtedly proof of your timepiece’s level of craftsmanship. Many of these pilot’s watches are accompanied by rich histories and eye-catching aesthetics, making them perfect conversation starters. Plus, while you may not need them every day, the watch does boast an impressive collection of fully-functional tools. If you need to solve a math problem and don’t have a calculator on hand, for example, you could use your slide rule!
Watches with these features are mostly geared toward pilot’s watch enthusiasts who are looking for something novel. They also make fantastic collector’s items. Classic pieces like the Breitling Navitimer and the Longines Hour Angle watch maintain relatively steady prices, making them more stable investments.
Read more
IWC Mark XVIII: More Than Just a Pilot’s Watch
Sinn 203 St: A Diving Chronograph With Pilot’s Watch Potential
Why is the IWC Big Pilot considered an icon among pilot’s watches?
