In this new timepiece, Patek Philippe combines two of its outstanding patented complications: the Annual Calendar and the Travel Time system for the display of a second time zone.
The date display is synchronized with the respective local time. It simultaneously adjusts the date when the time zone is corrected. The new self-winding caliber 31-260 PS QA LU FUS 24H movement is endowed with eight patents.
For this model, the manufacture created a totally new Calatrava case. Its flanks are guilloched with the inimitable hobnail pattern and its dial is framed in the vintage genre inspired by old photo cameras. The same unique design also graces the Ref. 5226G-001 Calatrava, a watch without an additional complication powered by the self-winding caliber 26-330 S C movement.
For Patek Philippe, the technical perfection and aesthetic beauty of a timepiece have always had the same significance. The composition of the movement, case, and dial is always in the focus of the manufacture’s creations.
With its self-winding movement that features two exclusive functions, its round Calatrava case with unique design and decorative features, and an inimitable dial, the new Ref. 5326G-00 Annual Calendar Travel Time delivers a perfect example of an approach that combines all facets of watchmaking artistry with balanced elegance.
In 1996, Patek Philippe merged all of its Genevan ateliers in Plan-les-Ouates under one roof and attracted attention with the launch of its patented Annual Calendar. It is a full calendar with day/date/month that only has to be manually corrected once a year on March 1.
To develop the system that automatically distinguishes between months with 30 and 31 days, the engineers designed an innovative mechanism based largely on wheels and pinions. Since then, the Annual Calendar has become a highlight among the manufacture’s complicated watches.
Today, it comes in a broad selection of ladies’ and men’s wristwatches and is also available in several self-winding flyback chronograph model versions. In the Ref. 5033, Patek Philippe even combined the Annual Calendar with a minute repeater movement.
It was followed in 1997 by a new technical launch, this time in the domain of travel timepieces. The exclusive Travel Time mechanism features a clutch based on a Patek Philippe patent granted in 1959. The ingenious system indicates a second time zone with a second hour hand from the center.
With two pushers in the left-hand case flank, it can be adjusted in one-hour increments in both directions without affecting the precise rate of the movement. Today, the Travel Time function is also available in various watch models, including the self-winding Ref. 5990 Flyback Chronograph or the Ref. 5520 Alarm Travel Time.
For the first time, Patek Philippe has extended its range of useful complications by combining the Annual Calendar and the Travel Time in one watch. The manufacture departed from the ultra-thin self-winding caliber 31-260 that had been launched in 2011 in the Ref. 5235 Annual Calendar Regulator (31-260 REG QA) and was then reworked in 2021 for the Ref. 5236 In-line Perpetual Calendar (31-260 PS QL).
Among the optimized features introduced in 2021, the new caliber 31-260 PS QA LU FUS 24H movement retains the 20% gain in barrel torque, the increased winding power of the minirotor thanks to the use of platinum, the frequency of 4 Hz (28,800 semi-oscillations per hour), and a reduction wheel that uncouples automatic winding when the watch is manually wound, which reduces wear. Energy-wise, the performance of the new movement was further improved by a minute wheel suspended between bearing jewels to increase efficiency.
The connection between the Annual Calendar and the Travel Time function involved several technical challenges. The issue wasn’t just to accommodate both mechanisms in the same case. They had to interact in such a way that the displayed date corresponded with local time, hence the time at the location of the wearer of the watch.
And it may need to be adjusted when the time zone is corrected. Thus, in the new caliber 31-260 PS QA LU FUS 24H movement, the Annual Calendar is controlled by the Travel Time function and it is the local-time hour wheel that drives the calendar. Connoisseurs will be delighted to note that the principle of the Ref. 5531 World Time Minute Repeater (2017) has been retained. It is the first minute repeater that always sounds local time because the World Time mechanism controls the minute repeater.
For the new Ref. 5326G-001, Patek Philippe redesigned the Travel Time function as well. While the basic principle with two hour hands from the center is retained (solid hand for local time, pierced hand for home time), the two common time zone pushers in the left-hand case flank were replaced with a winding-stem setting mechanism that has three positions. It premiered in 2021 with the Aquanaut Luce Travel Time (Ref. 5269/200R-001).
The user merely needs to pull the crown to the middle position and then turn it clockwise or counterclockwise to adjust the local-time hour hand in one-hour increments in either direction without affecting the precise rate of the movement.
Aesthetic reasons favored the decision for this discrete crown setting system: Patek Philippe wanted a sleek design in the Calatrava style to emphasize the special motif on the case flanks. Setting the time in the home-time zone is done in the classic manner with the crown in the outermost position.
The caliber 31-260 PS QA LU FUS 24H movement has a stop-seconds mechanism that allows the time to be set with one-second accuracy. This function is only active while the crown is pulled to the outermost position. This prevents the movement from stopping when selecting a new time zone and preserves the rate accuracy of the movement. When the owner is not traveling, the two hour hands can be superposed with the crown and will then look like one hand.
To make sure the watch always displays the date that matches the respective local time, the engineers also had to modify the Annual Calendar mechanism.
In a conventional annual calendar, the display advance around midnight lasts about 90 minutes, so a date misalignment could occur if the time zone is adjusted in this time span. To assure that users see the correct date longer, Patek Philippe’s engineers shortened the display advance of the Annual Calendar discs by a factor of 5 to about 18 minutes.
Thanks to a cam system with partial toothing connected to the hour wheel, the 24-hour wheel executes its rotation in four phases instead of continuously: 180° rotation in 3 hours (toward midnight), 9 hours of standstill, 180° rotation in 3 hours (toward noon), 9 hours of standstill. This improves the coordination of the calendar switching phase with local time. But the word acceleration also suggests higher energy consumption.
To optimize the efficiency, precision, durability, safety, and operating convenience of the caliber 31-260 PS QA LU FUS 24H movement, the engineers developed several innovations that resulted in eight patent applications. For instance, these technical refinements make it possible to reduce the energy consumption and wear of certain components, to switch from the 30th to the 1st and from the 1st to the 30th without desynchronizing the calendar when adjusting the time zone, to prevent shifts and double jumps of the displays or avoid damaging parts of the movement if the moon phase, the month, or the day of the week are corrected in a time frame during which this is explicitly inadvisable.
The sapphire-crystal case back reveals the architecture of the caliber 31-260 PS QA LU FUS 24H movement with the elegantly cut and gently curved bridges. It affords a better view of the wheels of the base movement and the exquisite manually executed finissage that reflects the strict directives of the Patek Philippe Seal.
The newly designed white-gold case has a diameter of 41 millimeters. With its slightly chamfered bezel and the polished, inclined lugs, it underscores the sleek and timeless elegance of the Calatrava design yet expresses its very own distinctive personality.
The case middle displays Patek Philippe’s signature hobnail motif along its entire circumference. The subtly shining pattern of tiny pyramids was showcased on the bezel of the famous Ref. 3919 Calatrava “Clous de Paris” in 1985; it was produced for over 20 years and became one of the best-known models of the watch world. In 2021, it experienced a strong comeback in the new, highly contemporary Ref. 6119 Calatrava “Clous de Paris” that is made in rose gold and white gold.
On the case of the Ref. 5326G-001 Annual Calendar Travel Time, it provides a new perspective of this very refined element of the Patek Philippe style. To allow the hobnail pattern to so elegantly adorn the complete flank of the caseband, Patek Philippe conceived an exceptional case design in which the strap lugs are attached to the case back.
The vintage-style dial is crafted entirely by Cadrans Flückiger in Saint-Imier, a dial specialist which has belonged to Patek Philippe since 2004.
The dial is charcoal gray with a fine gradation to the periphery and has a slightly granular structure that is reminiscent of the cases of old photo cameras. The time of day is shown by applied Arabic numerals in white gold with beige luminous coatings.
The hours of local time and the minutes are displayed with luminous white-gold “Seringue” hands that with their long tips resemble syringes. A pierced “Seringue” hand indicates the hours of home time. The three apertures of the Annual Calendar – day of the week and month on one line at 12 o’clock, date at 6 o’clock – show easily legible black inscriptions on white backgrounds.
Two small round windows marked “LOCAL” at 8 o’clock and “HOME” at 4 o’clock are day/night indicators for local time and home time, respectively. This balanced arrangement is complemented by the subsidiary seconds that sweeps the moon-phase aperture at 6 o’clock.
The calendar indications can be adjusted with the aid of small correctors in the caseband located near the respective functions: day at 10, month at 2, date at 4 and moon phases at 8 o’clock. The vintage aspect is emphasized with a slightly raised box-design sapphire-crystal glass.
The new Ref. 5326G-001 Annual Calendar Travel Time is delivered with two interchangeable straps, one beige calfskin with nubuck texture (original version), the other black calfskin with embossed textile finish and beige decorative stitching (additional strap).
The eight patents of the new caliber 31-260 PS QA LU FUS 24H movement
Time-setting with three crown positions (Swiss patent application CH 716383 A2): This time-setting system has a lever with three positions that can deactivate certain wheels as long as they are not performing any correction. This reduces energy consumption and wear of the respective wheels. The result is a gain for the balance amplitude (rate accuracy) and for reliability
Forward/backward mechanism for the Annual Calendar (European patent application EP 3776095 A1): This system relies mainly on the addition of a tooth and a spring on the month lever that allows the transition from the 30th to the 1st and from the 1st to the 30th without desynchronizing the date. Therefore, the user can easily switch the time zone forward or backward with the winding stem.
Linear time-zones spring (European patent EP 3650953 B1): This system consists of a star wheel and a jumper spring. It allows a strong torque increase between the local time hour wheel and the home time hour wheel and thus an acceleration of the date jumps despite the increase in energy consumption. It provides the user with more precise information.
Pivotable holding bridge (European patent applications EP 3714336 A1 and 070431/2021): This system keeps the day disc in position without the use of a center screw. To remove the disc, the watchmaker merely needs to pivot the bridge to the side. This releases the star without requiring the disassembly of the movement and without any modification of the settings. This timesaving and simplification is part of the improvements in watch maintenance.
Inertial delta (European patent application EP 3822711 A1): This mechanism offsets the inertia difference between a heavier and a lighter wheel. When the time zone is being corrected in either direction, it prevents an unintended forward or backward misalignment of the time displays (home time, local time, minutes). This increases the accuracy of the displays.
Braking mechanism for the date disc when a correction is made (European patent application EP 3882716 A1): This system with an additional spring (brake) is only active when the crown is pulled to the middle position. It prevents double jumps of the date disc if the user exerts too much force. It safeguards the greater reliability of the mechanism (amplitude gain and wear reduction).
Flexible correctors (European patent application 20205322.9): With a system of flexible leaf springs for switching protection purposes, this mechanism prevents the risk of a material failure when the user performs a correction during an unfavorable time window. This improves the reliability and longevity of the movement.
Model: Ref. 5326G-001 Annual Calendar Travel Time
Caliber 31-260 PS QA LU FUS 24H
Self-winding mechanical movement. Annual Calendar with aperture displays for the day, date, and month. Two Travel Time zones (local time and home time) with day/night indicators for local and home time
Moon phases and small seconds
Diameter: 33 mm
Inside case diameter: 31.74 mm
Height: 5.6 mm (2.6 mm for the base movement, 3 mm for the Annual Calendar and Travel Time module)
Number of parts: 409
Number of jewels: 47
Power reserve: Min. 38 hours, max. 48 hours
Winding rotor: Off-center minirotor in 950 platinum, unidirectional winding
Frequency: 28,800 semi-oscillations per hour (4 Hz)
Balance spring: Spiromax® in Silinvar®
Balance spring stud: Adjustable
• Pushed home: manual winding
• Pulled to middle position: Setting of local time in either direction in one-hour steps
• Pulled all the way out: Setting of home time with hours and minutes, stop seconds
• Hour hands for local and home time and minute hand from the center
• Subsidiary seconds at 6 o’clock
• Day and month on one line at 12 o’clock
• Date at 6 o’clock
• Day/night indicator for local time at 8 o’clock
• Day/night indicator for home time at 4 o’clock
• Moon phases at 6 o’clock
Month at 2 o’clock
Date at 4 o’clock
Moon phases at 8 o’clock
Day of week at 10 o’clock
Patek Philippe Seal
18K white gold
Sapphire-crystal case back
Water resistant to 30 m (3 bar)
Case dimensions: Diameter: 41 mm
Height (crystal to display back): 11.07 mm
Granular, charcoal gray with black gradation to the periphery
Applied numerals in 18K white gold with beige luminous coating
Railway track minute scale and beige printed markers
Seringue hands for local time hours and minutes, 18K white gold with beige luminous coating
Pierced Seringue hand for home time hours, 18K white gold, lacquered beige
Small seconds with dagger hand, 18k white gold lacquered beige
Calfskin with nubuck finish, hand-stitched, beige
Delivered with additional calfskin strap with embossed textile pattern, black with beige decorative stitching
Fold-over clasp in 18K white gold