I found my copy of Wernher von Braun's monograph "Das Marsprojekt"  (only two 
words, not three) which was published in 1952 and written, no doubt, a full 
decade before SI was formalized in 1960.

It consists of a complicated mix of centimeter-gram-second units, entangled 
with metric "gravitational" units  in the form *meter, ton(force), second* 
units.

The ton force "t" is not defined, but I assume it is exactly 1000 kg-force, 
i.e. 1000 x 9.800665 newtons.

The word mass is not used.  Vehicle "Gewicht" is given in units of t.  Thrust 
is also given in units of t for each rocket stage.

Propellant flow rates are in "t/sec" for each stage.

It is amazing that von Braun did not use an absolute system of units based on 
mass for the "free fall" environment of travel to Mars, but it not surprising 
that the German engineers quickly adopted SI in Huntsville, Alabama when they 
learned of the CGPM adtions of 1960 formalizing SI for all applicalions.  

The duplicate below was posted by mistake before I was able to complete the 
change to the above subject title.

Gene.

---- Original message ----
>Date: Sun,  6 Feb 2011 16:27:56 -0600 (CST)
>From: <[email protected]>  
>Subject: [USMA:49789] German R  
>To: "U.S. Metric Association" <[email protected]>
>
>---- Original message ----
>>Date: Sat,  5 Feb 2011 11:06:00 -0600 (CST)
>>From: <[email protected]>  
>>Subject: [USMA:49761] RE: Super Bowl: NFL, stop with the Roman numerals  
>>To: "U.S. Metric Association" <[email protected]>
>>
>>The German rocket engineers used metric *gravitational* units, i.e. 
>>meter-kg(force)-second units, not SI.  von Braun's monograph "Das Mars 
>>Projekt" was also m-kgf-s, but to their credit they were the first NASA 
>>Center to adopt SI which is a metric "absolute" system, 
>>meter-kilogram(mass)-second.
>>
>>You are mistaken to imply that NASA Research Centers have abandoned SI.  Only 
>>NASA-Houston (manned space flight) has not used SI (for the Shuttle).
>>The canceled Constellation Program tried to revert to inch/pound units.
>>
>>Gene.
>>
>>---- Original message ----
>>>Date: Sat, 5 Feb 2011 09:40:27 -0500
>>>From: "Kilopascal" <[email protected]>  
>>>Subject: [USMA:49753] RE: Super Bowl: NFL, stop with the Roman numerals  
>>>To: "U.S. Metric Association" <[email protected]>
>>>...
>>>   I will disagree with you about you comment on Space
>>>   Flight.  America's greatest achievements in Space
>>>   Flight came when it was under the direction of
>>>   Werner von Braun, a German who did all of his
>>>   designs and conceptualizing using metric units.  In
>>>   an interview in the early '70s he told the
>>>   interviewer that he never used USC and loathed it.
>>> ...   
>>
>

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