Breitling Navitimer and Apple Watch: which references fit
Founder & CEO, Smartlet - CentraleSupelec engineer - Concours Lepine 2025, Awarded - CES 2026
Contents
The Navitimer has always been a computer you wear. Its bezel is a circular slide rule, built in 1952 for members of the Aircraft Owners and Pilots Association who needed fuel burn and rate of climb without a calculator. Seventy years on, the people who buy one tend to wear a second computer too, the one that counts their heart rate and buzzes when a gate changes. The question is whether both fit on one wrist. For most Navitimers, yes. For a handful of references, no, and the reason is smaller than you would guess.
- Most current Navitimers fit. Lug widths run 18mm on the 35 and 36, 20mm on the 38, 22mm on the 41 and 43, 24mm on the 46, all on spring bars.
- Some references do not. Breitling publishes a few at 22.05mm or 24.05mm, and a Smartlet watch adapter is sized to the whole millimetre.
- The Navitimer 32 is out. At 16mm, it sits below the 18 to 24mm range.
- Check the reference, not the family. Two Navitimers of the same size can get different answers.
- The setup. Navitimer on top, dial to the sky, Apple Watch underneath against the skin, both on one metal link bracelet.
The slide rule and the sensor
A Navitimer answers questions about the flight. Distance over time, fuel over distance, a unit conversion when the controller speaks in knots and you think in kilometres. It does that with a rotating bezel and a scale, no battery, no signal. Nothing about the instrument has changed in its job since the fifties.
An Apple Watch answers questions about the pilot. Heart rate on a long leg, the sleep you did or did not get before an early report, the message that the crew bus is late. Two different instruments, two different subjects. The traveller's version of this argument is laid out in two clocks, one wrist, and the cockpit version is the same, only louder.
Wearing one on each wrist works until you need a hand free. Which, in a cockpit or a boarding queue, is most of the time.
Which Navitimer fits
Our compatibility base lists the current Navitimer line reference by reference, each one checked against a published width and a published attachment. By case size, the pattern is almost boring.
| Navitimer | Lug width | Smartlet |
|---|---|---|
| Automatic 35 and 36 | 18mm | Yes |
| Automatic 38 | 20mm | Yes |
| Automatic 41, B01 Chronograph 41 | 22mm | Yes, most references |
| B01 Chronograph 43 | 22mm | Yes, most references |
| B01 Chronograph 46, Chronograph GMT 46 | 24mm | Yes, most references |
| Navitimer 32 | 16mm | No, below range |
The B01 Chronograph 43, the one most people picture when they say Navitimer, has its own compatibility page. For the rest of the catalogue, the Breitling page goes reference by reference.
The five-hundredths problem
Here is the part nobody expects. Breitling publishes the lug width of some references not as 22mm but as 22.05mm, or 24.05mm. Five hundredths. The difference is about half the thickness of a sheet of paper, and on a leather strap it would not matter at all. Nobody would ever notice.
A Smartlet notices. Its watch adapters are ordered in an exact width, to the millimetre, and seat directly in the lug holes, with no leather to absorb the slack and no soft spring to take up the difference. A watch adapter cut for 22mm in a gap of 22.05mm is one that can move. We would rather say no than ship something that sits almost right on a watch you care about. So those references are listed as not compatible, including a few Automatic 41, Automatic GMT 41 and B01 Chronograph 46 references, plus the B19 Perpetual Calendar and B03 Rattrapante.
Two Navitimers that look identical can get different answers. Look up your exact reference in the Smartlet finder before you order, not the model name. The lug hole and the pin explains why the hole decides everything.
How it wears
The Navitimer goes on top, dial to the sky, where the slide rule stays readable. The Apple Watch sits underneath against the skin, on the adapter that comes in the box, which is where its sensors read anyway, and one metal link bracelet carries both. Turn the wrist and the screen is there; leave it and the room sees a Breitling.
A B01 Chronograph 43 is not small. The Titanium edition in Grade 2 is the lightest option, and an airline pilot in our stories describes wearing it through a transatlantic rotation. The Classic in brushed steel suits a steel Navitimer, the Shadow a black dial.
For high-impact activity, keep your Apple Watch on its standard strap for that session. A Navitimer was never a gym watch either.
Before you order
Find the reference on the caseback or the warranty card, run it through the finder, and read the answer as it is: yes, no, or ask us. If you also fly with a field watch, the Sinn 103 and GMT watches follow the same logic, and why pilots still trust mechanical watches covers the rest of the cockpit argument.
Smartlet, Bronze Medal at Concours Lepine 2025 and selected for CES 2026, carries the slide rule and the sensor on one wrist. Discover the collection.
