lot 01


Big Pilot B-UHR

This watch was featured at the "German-Speaking Watches" auction

Starting bid CHF 10 000
Hammer price CHF 21 000
Buy now price CHF 28 800
Total bids 22


CaseOversized stainless steel case, with a solid stainless steel & anit-magnetic caseback, oversized pilot's crown
DialBlack dial with luminous indices & Arabic numerals, blued steel hands with luminous inserts
MovementYellow gold plated hand-wound movement, with blued Breguet hairspring, swan-neck fine adjustment, central seconds
Movement No.1014697
Case No.1034037
YearApprox 1940

Condition report

Case:Good, signs of wear (according to IWC crown is replaced)
Dial:Good, signs of patina
Movement:All functions working
Amplitude (Dial on top/Lift angle 52):Approx 280°
Accuracy (Dial on top):Approx +60 sec/day


A very rare and charismatic oversized stainless-steel military wristwatch made for the German Air Force in World War II, with corresponding stamped inscriptions on the caseback. Produced in 1940 by the famous Swiss watch brand IWC Schaffhausen, founded in 1868. Case made of stainless steel, diameter 55mm, 17.5mm thick, solid-steel caseback stamped outside with movement serial number and inside with panel indicating the type of watch, manufacturer, again the movement serial number, ‘FL’ number, material info and case serial number. ‘FL’ number stamped again on case band at 9 o’clock. Matte black dial, blued steel sword-shaped hands and central seconds hand with patinated luminous radium compound, patinated luminous radium Arabic numerals and markers of the minutes track. Caliber 52 T.S.C., hand-wound, hacking seconds. Functions – indication of time in hours, minutes and seconds. 

Lot essay 

IWC is known as a manufacturer of archetypal technical, aviator and military watches. The present B-Uhr, or Beobachtungs-Uhr (observation or navigation watch) is one such archetype. The watch was made in 1940 by order of the German Air Force (Luftwaffe), and was intended for their pilots. In addition to the Swiss brand IWC, similar watches were ordered from the German factories A. Lange & Söhne, Lacher & Co (Laco), Walter Storz (Stowa), and Wempe. However, the most famous is the B-Uhr from IWC. It should be noted that during the Second World War, IWC, operating in a country with neutral status, also supplied watches for the Ministries of Defence of Allied countries. This connection brings to mind the famous ‘dirty dozen’, produced for the British MoD. 

The B-Uhr watches were built to Luftwaffe specifications, which called for a very large 55mm case, a large pocket caliber with a hacking seconds feature, and a large crown allowing the pilot to operate it without taking off his gloves. A hacking central seconds hand is capable of being stopped by pulling the crown, allowing pilots and navigators to synchronise their watches before the start of a mission with down-to-the-second precision. The watch had to be equipped with anti-magnetic protection, as well as a long leather strap that would allow the watch to be worn over the sleeve. The B-Uhr standard described the dial of one of two obligatory designs: Type A dials featured Arabic numerals and a large triangle at 12 o’clock along an outer minute track, as in the present example, while the Type B dials had an inner hour track, short hour hand and outer minute track for long minute and seconds hands. 

The B-Uhr watches were built to Luftwaffe specifications, which called for a very large 55mm case, a large pocket caliber with a hacking seconds feature, and a large crown allowing the pilot to operate it without taking off his gloves.

From the outside, the B-Uhr watch has no other markings, including on the dial, except for the movement number stamped on the caseback and FL.-Number on the case band on the left side. All technical information is located on the inside of the back cover of the case, exactly as in this example. It includes the design type (Bauart; here is the manufacturer’s abbreviation), caliber serial number (Werk Nr.), and order number (Anforderz) – this is a so-called FL.-Number, where ‘FL’ denotes ‘flying number’ (Fliegnummer), the first two digits, 23, stand for navigation purpose, followed by the three digits of the order’s number. A detailed description may be found in the book ‘Die Fliegeruhren von IWC’ by Rüdiger Bucher and Christian Pfeiffer-Belli. In addition, the name of the material is stamped on the case back – “Rostfreier Stahl” (stainless steel), along with the case serial number. All numbers correspond to the number ranges of the B-Uhr series, issued by IWC in 1940. 

The high-end caliber 52 T.S.C. of the present example has a mainplate and bridges with a gilded and frosted finish, a large cut compensated balance wheel, a blued Breguet spiral, carefully finished steel parts with polishing and open wheels with a snailed finish. The caliber is marked with the ‘IWC’ hallmark. A total of 1200 such movements were manufactured by IWC and bore the serial numbers from 1013801 to 1015000. 1000 of these were delivered to the Luftwaffe as B-Uhr watches. While the watches of the initial batch were fitted with a cylindrical crown, the later batch had the conical crowns that we associate so strongly with B-Uhr watch design. The remaining 200 caliber 52 T.S.C. movements were delivered to the British Royal Navy to serve as deck watches. Therefore, the total production of the IWC B-Uhr was 1000 pieces, and for obvious reasons not all copies have survived to the present. This, of course, enhances their collectibility today. 

Reasons to bid 

The IWC B-Uhr Ref. 431 would appear to be an attractive purchase for the collector who desires a very rare, collectible and iconic oversized military wristwatch from a world-famous traditional watch brand, earning a reputation as one of the leading manufacturers of technical and military watches. The IWC B-Uhr, nowadays referred to as the ‘Big Pilot’s Watch’, is one of the few world-famous archetypes of military wristwatches. The present lot is a monument to the era of the Second World War, and to the skill and ingenuity of watchmakers who developed technically advanced and extremely attractive pilot’s watches. It represents the origins of an impressive and world-famous military style, the style of the ‘Big Pilot’s Watch’, and features the hallmarks of high-class watchmaking, which are seen above all in the fine finishing of the high-quality pocket-watch caliber 52 T.S.C.