|Reports are supplied at the request of the customer
and it is for the customer's exclusive use. Reports express an opinion of the time of the
examination of the jewelry. This report is for customers use only for the following two
purposes, indicating estimated retail replacement value to obtain insurance coverage, or
for the purpose of providing geological information. GoldSmith Works does not guarantee
that the appraisal valuation will result in a sale at the price. Estimated retail
replacement value is arrived after analyses of what the approximate high retail cash
asking price is for labor, materials, and design. These prices may be substantially higher
than actual transaction or warranty with regards to any item described in the report,
since jewelry grading is not an exact science, this report represent the best
opinion of the company. GoldSmith Works is in no case responsible for differences that
occur by repeated grading by other experts in the field and/or use of other standards,
norms, methods or criteria other than those used by GoldSmith Works. GoldSmith Works is
expressly held harmless by customers including, but with out limitation for any claims or
actions that may arise out of negligence in connection with the preparation of this
laboratory report, or actions based upon the customer's use of the report. The information
on the carat weight, clarity grade, color grade on the report is approximate due to the
limitations in jewelry grading. The item was tested, graded, and examined under 10x
magnification using the techniques and equipment available to GoldSmith Works, including
fully corrected triplet loupe, binocular microscope, master color comparison guides,
diamond color comparison tools, electronic carat balance, non-contact optical measuring
device, and ancillary instruments necessary at the time of Examination.
W.W. I I WALTHAM A.F.U.S. ARMY A-11 PILOTS HACK WATCH
In 1942 specifications were issued by the Army for a navigation hack watch designated the
U.S. A.A.F A-11. The A-11 was more complicated than the B-1. The A-11 specifications
called for a minimum 15-jewel movement and was put through a *program to meet certain
standards of abuse tolerance and accuracy and was put out for contract with a much more
detailed specification sheet. It represented the militarys acknowledgement that
timekeeping was a critical element of modern warfare.
The A-11 hack watch was an AAF item issued to pilots and navigators and were worn to give
the crewman an approximate timeframe for navigation, assembly times, etc. Benrus,
Bulova, Elgin & Waltham produced watches for the military, including the A-11, the
renamed Army Air Force primarily utilized the Waltham A-11 with the 6B/234 specification
of black dialing, white numerals and a hack feature.
A characteristic design distinction between the A-11 and the other 6B/234 Navigators
watches was that it featured additional Arabic numerals outside of the minutes chapter
ring to denote 10 minute increments
The "hack" nickname for the A-11 comes from the fact that when the winding stem
is pulled out, the sweep second hand stops moving. It will start moving again when the
stem is pushed back in against the case. The hack feature also meant that the seconds hand
jumps from one second mark to the next, rather than moving smoothly.
Army officers and NCO's were issued wristwatches procured by the Ordnance Department. If a
paratrooper officer or NCO had an A-11, they would have gotten it by trading for one or by
some other means.
A-11's were not widely available and were closely controlled in the AAF supply sytem.
Throughout the war center-seconds remained the primary distinction between the Navigators
hack watch and the basic military wristlet field watch, due to the added expense of
The definitive Navigators hack watches of the Allied and Axis powers shared the same basic
characteristics: Black Dial, White Arabic Numerals and Indices, White Hour, Minute, and
Center-Seconds Hands; but adopted radically different sizing.
Both the US and England utilized the A-11.
By contemporary standards they were small watches, around 31mm, but highly legible.
navigation hack watch performance specifications
From US ARMY SPECIFICATION NO. 94-27834-B, dated FEBRUARY 22, 1943 - WATCH, NAVIGATION,
TYPE A-11 (HACK):
F. METHOD OF INSPECTION AND TESTS:
F-5. Individual Tests.- Each watch shall be subject to the following tests:
F-5a. Room Temperature Rate Test - Horizontal Position. - The watch shall be fully wound
and run for one day to allow it to settle down. The daily rate of the watch then shall be
determined for a period of 3 consecutive days with the watch in a horizontal position with
the dial up and with a daily winding. The average of the daily rates during the test
period shall not exceed 30 seconds.
F-5b. Room Temperature Rate Test - Vertical Position. - The daily rate of the watch shall
be determined for a period of 3 consecutive days with the watch in a vertical position,
with the pendant down and with daily winding. The average of the daily rates during the
test period shall not exceed 30 seconds. The difference between the average daily rate
obtained in this test, and in the test specified in Paragraph F-5a, shall not exceed 45
F-6. Routine Type Test. - The following tests, in addition to those specified in Paragraph
F-5, shall be applied to not less than 5 watches selected at random from each hundred or
fraction thereof that are contracted for.
F-6a. Plus 35 Degrees Centigrade (Plus 95 Degrees Fahrenheit) Temperature Rate Test -
Pendant Down Position.- The watch shall be fully wound and then subjected to a temperature
of plus 35 degrees Centigrade (plus 95 degrees Fahrenheit) for a period of 5 hours. During
this period, the daily rate of the watch shall not differ more than 20 seconds from the
average daily rate obtained in the test specified in Paragraph F-5b. (In order to arrive
at the correct figure for the rate allowance for the temperature test, the error noted for
the 5-hour period shall be multiplied by 4.8 in order to determine the rate for 24 hours).
F-6b. Zero Degrees Centigrade (Plus 32 Degrees Fahrenheit)- Temperature Rate Test -
Pendant Down Position. - The watch shall be tested as descrived in Paragraph F-6a, except
that the watch shall be at a temperature of zero degrees Centigrade (plus 32 degrees
Fahrenheit). The daily rate of the watch shall not differ more than 40 seconds from the
daily rate obtained in test specified in Paragraph F-5b.
F-6c. Waterproof Test. - The watch shall be suspended above a beaker of water placed in a
vacum chamber which shall be evacuated to 5 1/2 inches of mercury (to simulate a condition
of 72 inches of water), then the watch shall be immersed for a period of 15 seconds. There
shall be no evidence of leakage of water into the watch during the test period. Leakage
will appear as bubbles emanating from the back, crystal, or stem of the watch.