2006, the year of the 30^th anniversary of the Nautilus collection, saw the introduction of Reference 5980/1, Nautilus flyback chronograph. This model was joined in 2014 by Reference 5990/1, Nautilus Travel Time Chronograph, initially offered in a steel version (5990/1A-001), complemented in 2021 by a rose gold version (5990/1R-001).

As the successor to the 5990/1A-001, Patek Philippe has revisited the steel version by combining it with a new blue dial featuring a radiant sunburst pattern and a black-gradient rim. A perfect example of legibility, this dial is enhanced by the horizontally embossed motif typical of Nautilus watches and is adorned with applied hour markers and white gold rounded baton-style hands, all with luminescent coating.

The case water-resistant to 120m, octagonal bezel, chronograph pushers (at 2 and 4 o’clock), local time pushers (at 9 o’clock) and steel bracelet are enhanced by elegantly alternating polished and satin finishes.

Self-winding CH 28-520 C FUS caliber combines three useful and practical complications: a flyback chronograph, a Travel Time function (dual time zone with two central hour hands, one of which is skeletonized for home time) and a date indicated by hand (at 12 o’clock) coupled with the local time. Its original construction combines tradition (column-wheel drive) and the avant-garde (vertical disk clutch). The flyback function enables instant restarting of timing operation without first having to stop the hands. The central chronograph hand can also be used as a running seconds display.

The steel bracelet with patented Patek Philippe fold-over clasp, secured by four independent catches, is equipped with a new lockable adjustment system that makes it possible to gain 2 or 4 mm in length thanks to simple, quick and secure handling, thus ensuring greater comfort in everyday life.

The new Reference 5990/1A-011 replaces Reference 5990/1A-001 and joins the existing Reference 5990/1R-001 in the collection.

• Self-winding CH 28-520 C FUS caliber, with flyback chronograph and Travel Time function
  
• The skeletonized hand displays home time while the solid hand indicates local time. Day/night indications in apertures for local and home time
  
• Date coupled with local time and displayed in a subdial at 12 o’clock. 60-minute chronograph counter at 6 o’clock
  
• Porthole-inspired case construction. Case, bezel, pushers and bracelet with contrasting polished and satin finishing
  
• Time-zone pushers integrated into the case at 9 o’clock
  
• Steel bracelet with patented Patek Philippe fold-over clasp and new lockable adjustment system

Reference	:	5990/1A-011
Case	:	Steel
Diameter	:	40.5 mm (10–4 o’clock)
Height	:	12.53 mm
Water resistance	:	120 m
Crown	:	Screw-down
Case-back	:	Sapphire crystal /td>
Dial	:	Sunburst blue with black-gradient rim Horizontally embossed Gold applied hour markers with luminescent coating Local time hand: white gold, rounded baton-style with luminescent coating Home time hand: skeletonized white gold, rounded baton-style, white varnished
Displays	:	Hour hand for local time (solid) Hour hand for home time (skeletonized) Minute hand Chronograph hand/sweep seconds
Subsidiary dials	:	60-minute counter Date
Apertures	:	Day/night indication for home time (HOME) Day/night indication for local time (LOCAL) Two-position crown: Unscrewed: to wind the watch Pulled out: to set the time
Pushers	:	Adjustment of local time (press once = +1 hour) Adjustment of local time (press once = -1 hour) Chronograph start and stop Chronograph reset and flyback function
Corrector	:	Date correction
Mouvement	:	Caliber CH 28-520 C FUS Self-winding Flyback chronograph Central chronograph hand 60-minute counter Two time zones: local and home time indication Day/night indication for local time and home time in apertures Date coupled with local time by hand
Diameter	:	31 mm
Height	:	6.95 mm
Components	:	370
Winding rotor	:	21K gold central rotor
Frequency	:	28,800 semi-oscillations per hour (4 Hz)
Power reserve	:	Min. 45 hours - max. 55 hours
Bracelet	:	Steel
Buckle	:	Patented fold-over clasp with lockable adjustment system