Martin Brenner's, Pilot Balloon Resources 

Pibal Theodolite Models and related items
These pages contain information on Pibal Theodolites that I have acquired with the exception of the Cook Troughton & Soms S25.   Most of these instrument models are no longer in production.  Check the Theodolite Manufacturers Section for models an links to current production units.

AШT (ASHT) Aerological Theodolites Two theodolite models produced in Moscow 1971 and 1984.  They are well designed compact instruments.  Manufactured during the cold war, one with a manual is printed in Russian, English and French.  Theses example were acquired from the Ukraine  and Kiev in 2003.  The CFJ-IIB below may be derivative of these models, however the CFJ-IIB it lacks the internal filters of the AШT models.  

Askania Balloon Theodolite, This is 1940's vintage German balloon theodolite possibly a Model Gt1.  

Askania Recording Balloon Theodolite.  This is a mechanical recording balloon theodolite. It imprints on paper tape.  

ATK-2 Aerological Theodolite built in 1961.  It is similar in size to the other Soviet (Russian) theodolites but a bit heavier.  This theodolite uses 60 part verniers, yielding 1 minute resolution viewable inside the eyepiece.   

Buff and Buff Theodolite In the 1920's this was the mainstay of U.S. Meteorological Observations until the adoption of the David White Series exemplified by he 6061 below.  The theodolite illustrated here is a vernier type and is seen in publications from the 1920's military and civilian.  An example was acquired by the Smithsonian in 1923.

Cary Model D pilot balloon theodolites were built in the first part of the 20th century.  The Cary Model D is a first generation design pilot balloon theodolite that was used in the United Kingdom prior to the introduction in 1937 of the Met Office Pattern Theodolite. 

CFJ-IIB WeatherMeasure 8304.  This Chinese theodolite was imported in very small numbers during the Late 1980's.  It is one of the most modern designs for mechanical pibal theodolites.  Extremely small, light and easy to use.  

Chinese, Model 71 unknown manufacturer 30X .  This Chinese theodolite is very large 30 power modern design.  Likely produced in 1971, it was purchased and imported as military surplus in 2006.  

Chinese, Model 70-1, unknown manufacturer 20X.   This is an instrument that is standard power, of a similar design to the one above but smaller.   It was purchased in imported as military surplus in 2007.   

A. Clarkson & Co LTD SM1 Pilot Balloon Theodolite. This is Clarkson Licensed Production unit.  It represents the final example in a series of theodolite that is the standard in the meteorological services of the British Commonwealth.

Cooke, Troughton & Simms LTD. Model S25 Balloon Observation Theodolite.  This information was sent to me (photocopied from a 1928-1930 catalog) by E. Ross of Auckland New Zealand. 

David White Model 6061.  This is the model illustrated in most of the older texts.  Production dates back to at least 1941.  I purchased an example in November 1998.   It is almost identical to the Warren-Knight model 84 and similar to current production 20-8403 below except that the W-K 84 and 6061 use a different battery case (permanently attached to the instrument.)   Later 6061 units and all Warren-Knight units are constructed with a number of aluminum components.

Keuffel and Esser marine theodolite.   Marine theodolites are complex rare instruments.  In addition to gimbal mounting, these instruments operate less like transits and more like sextants. They do not measure vertical angles by moving a telescope.  A rotatable mirror is used and the vertical angle is read off an arc with an index and a driven by a tangent screw with micrometer.   This design is more suitable to shipboard use and includes a bubble based artificial horizon.

G. Gerlach Pilot Balloon Theodolite.  An example of an early design made in Warsaw.  An acquisition from a dealer in Germany, who stated that the instrument dates from the very early 20th century.

Gurley Aero Model Pibal Theodolite.   This is an example of a basic conventionally designed balloon theodolite.  This instrument was built in 1942.   The Gurley Aero uses friction gearing attached to milled heads for slow motion control of azimuth and elevation.  This arrangement necessitates the use of vernier scales as friction gearing does not support micrometers.  Gurley Aero units were built with or without lighting, and lack a secondary wide angle telescope.  They do have a gun site.   I contacted Gurley's historical division they had no information on their production balloon theodolites other than dates of manufacture. 

Dr. Kölzer-Sprenger pilot balloon Theodolite.  This example was produced in Berlin German in 1938.  It is a classic German instrument allowing reading from the front or back of the instrument.   

Nikko Pilot Balloon Theodolite This Japanese theodolite model dates from World War II.  It is similar in appearance and function to the Watts Mark B.  It allows reading from the front and back of the instrument (elevation only).  

R & A Rost (after Dr. Kölzer-Sprenger) Balloon Theodolite.  This theodolite acquired from R & A Rost of Vienna Austria is more recent variant of the Kölzer-Sprenger Berlin theodolite.  This design may also be a descendant of the Gerlach theodolite above.  

Siap balloon theodolite.  This instrument built by Siap of Italy is very similar to the Askania theodolite above.

Tamaya BT-901 model Pibal Theodolite. This is a optical manual (no electronics) theodolite. Tamaya currently makes electronic balloon theodolites.  I have photos of a WWII vintage theodolite below.

Tamaya WWII Vintage Theodolite.  Model Number unknown, used by the Japanese during the second world war. 

Troughton and Simms Pilot Balloon Theodolite.   This English theodolite was produced in 1921.   It is very similar to the earliest E. R. Watts Designs.  

Warren-Knight Model 20-8403  and Warren-Knight Model ML-474GM Pibal Theodolites.  Warren-Knight produced a number of variants of this design over the years.  Models include 83, 84, 85 and current numbering 20-8403(standard mil spec for pibal work)  20-8350 (telemetering-Large 50 part micrometer drums, no compass, 10 turn potentiometers attached to tangent screws), 20-8500 (no compass 6.8V lamps, power connector - no battery box), Model 84 (similar to David White 6061 above, different battery case, and square rheostat housing) Model 474 (green painted version of Model 6061 above, square rheostat housing), Aero 1928-USN (green paint, no compass, no wide angle telescope, no battery box).

Warren-Knight Model 20-9103.   This is a high accuracy digital pilot balloon theodolite that was designed to allow other uses such as alignment of ILS gear and other tasks.

Watts Met. Office Pattern Theodolites (United Kingdom) Watts Theodolites are closed frame units originally designed to meet a Meteorological Office Specification.  The Vertical circle is geared so that it is parallel and directly above the horizontal circle.  Both scales are directly above each other, read through the same window.  There is a magnifying glass over the window like an older sextant although the numbers are easy to read without it.  The units also have micrometers.  They are about 2/3 the size of the Warren-Knight units.  They have similar features to Warren-Knight units including wide angle scope switch, gun site, and lighting.  The ergonomics of these theodolites are excellent.  Recent generation instruments are supplied with a set of colored filters that slip over the eye piece. 

Windsway Windreader offered an advance in pibal tracking, an affordable package containing a conventional optical theodolite with the addition of azimuth (electronic compass) and elevation sensing (accelerometer) components at a cost of about 1/3 of a traditional electronic pilot balloon theodolites.

Carl Zeiss Jena Recording Balloon Theodolite.  This design dates back to at least 1935.  The theodolite records the balloons path on a foil covered paper disk.