gravity wrote:

please read the NIST publications which define the Avoirdupois pound in
terms of kilograms. this is not debateable since NIST is *the* authority in
the US.

The NIST publications define the numeric conversion factors, not the
legality for use of any particular terminology.

The approximate conversion factor for a pound (mass) is 0.4535924 kilogram.

The approximate conversion for a pound (force) is 4.448222 newton.

The gravitational acceleration, small g, is defined as exactly 9.80665
in SI units, but it is not similarly defined in inch/pound units.

Interestingly enough, however, is that the ratio of pound-force per
pound (lbf/lb) (thrust to mass ratio) is exactly converted to newton per
kilogram (N/kg) by the factor 9.80665.

The position of the US Government can be summarized from the following
excerpt found in Federal Standard 376B, Preferred Metric Units for
General Use by the Federal Government.

In the intro to the section on mass there is a note that says,

*** There is ambiguity in the use of the term "weight" to mean either
force or mass. In general usage, the term "weight" nearly always means
mass and this is the meaning given the term in U.S. laws and
regulations. Where the term is so used, weight is expressed in kilograms
in SI. In many fields of science and technology the term "weight" is
defined as the force of gravity acting on an object, i.e., as the
product of the mass of the object and the local acceleration of gravity.
Where weight is so defined, it is expressed in newtons in SI. ***

The document then goes on to show many conversion factors from both
pounds (mass) and pounds (force) to SI units. No indication that one is
more legal or correct than the other.

Soooo, use pounds any way you wish; just do the math correctly.

73,
Gene
W4SZ