In article BTiz writes:
On Aug 17, 7:56=A0am, Tony wrote:
Curious,

Sporting Code 3 defines the Ultralight Class as a take off weight of
less than 220 kg, or 485 lbs. =A0Is this maximum allowed takeoff weigth
or the actual weight of the glider for that flight?

Tony... as I read the sporting code.. they always refer to "Mass",
whether it be max or minimum attainable.
So to me, in the US to read, "ULTRALIGHT, a glider with a takeoff mass
not exceeding 220 kg," that means maximum gross weight.


Much of the world does not report weights of things, but they report
masses in kilograms (or grams). A mass of 220 Kg would "weigh" 485 pounds.

There is no reason for the use of a mass measurement to imply that it
is the certificated maximum gross takeoff weight.

It could be:

1. The empty weight. This is how the part 103 definitions are
written.

2. The weight as actually flown.

3. The maximum legal gross weight at takeoff.

Since we do our flying on a planet with a fairly constant gravitational
accelleration, we can safely use mass or weight units of measurement.


Again, the international code refers to MASS because that is the way
that most of the world records these things.

(NOTE: often they measure with a spring scale, which is actually
measuring force, but it may indicate the mass (assuming normal earth
gravity).)


Alan