On its release in 2000 in the limited-edition IWC Portugieser 2000, IWC's Cal. 5000 was lauded by the brand's followers. It marked the restart of completely-in-house watch movement development for the company and brought back the legendary Pellaton winding system. The movement was seen as a landmark in other ways, with 8-day power reserve, automatic winding, and a massive 16.75 ligne (38.2 mm) diameter.
In 2002, IWC introduced the Big Pilot's Watch, Ref. 5002 with a new version of the Cal. 5000. The new Cal. 5011 brings central seconds and a date window to the movement family for the first time. The circular power reserve indicator dial at 3 00 remains, giving watches using this movement a unique appearance. Cal. 5011 was updated in 2006 with faster 21,600 A/h operation to become Cal. 51110, and was used in the new Big Pilot's Watch, Ref. 5004. This was further updated in 2008 as Cal. 51111, which continued in Ref. 5004 and was also used in Ref. 5009 after 2012.
The fact that Cal. 5000 uses a single mainspring and barrel has impacted the reputation of this movement. As admitted by Richard Habring and other IWC staff, the watch was meant for “weekend wear” and is thus tuned to keep time accurately over a week. But the single mainspring does not deliver power consistently, so the movement runs quite fast for the first two days, more predictably for the next few, and slows down at the end. This causes issues for timing, maintenance, and daily wear. The next-generation Cal. 52000 family used double barrel construction to deliver more consistent torque and timing throughout the week.