With this it would be:
- max_weight: the maximum weight of the complete vehicle (including
truck and trailer, in the German traffic rules (Straßenverkehrsordnung,
StVO) that's a "Zug"; if I interpret my dictionary right, in English
it's a road train.
-1
There is no (common) restriction that limits the actual weight of
truck+trailer, thus it makes no sense to define maxweight as limit for
the complete train.
Let me explain:
http://commons.wikimedia.org/wiki/File:Zeichen_262.svg
limits the permissible weight of a *vehicle*. The truck and the trailer
are TWO distinct vehicles (!), thus - for the sign given above - the
truck alone and the trailer alone must stay below 5.5t. The complete
train may have a weight up to 11t!
This it is not a good idea to define maxweight as weight limit for a
road train. Instead we keep 'vehicle', the legislation of the country
will define what is a 'vehicle'.
Mappers should not have to worry about the exact interpretation of
'vehicle' in the context of semitrailers, agricultural tractors with
trailers, etc.
- maximum gross weight: (however the tag is called then): the maximum
weight the complete road train is allowed to have if fully loaded.
This sign
http://commons.wikimedia.org/wiki/File:Vorschriftszeichen_7a_Gewicht.svg
restricts the gross weight. But for highest level of confusion and
inconsistency, the Vienna Convention restricts the gross weight of
"vehicle or combination of vehicles" and not just vehicles, thus
contrary to the road sign above, the trailer must be included. I sadly
overlooked this.
Thus if we define maxgross_weight per vehicle, the road sign cannot be
tagged as maxgross_weight:hgv=5.5 as proposed. The proposal needs a fix!
Since it applies to "vehicles plus any trailers" and not just vehicles
(which are defined differently). And defining it as vehicle+trailer will
add confusion and may not work in the international context outside the
Vienna Convention countries.
Any suggestions how to fix this?
a) Introduce maxgross_train_weight=X?
b) Keep maxweight=X, flush maxgross_weight (looks odd anyway) and add a
new tag:
maxweight:type=gross_vehicle, gross_train, laden, empty, etc.
to qualify the maxweight?
I would additionally define that the definitions + _weight can be used
as properties in conditional restriction, eg. maxspeed=80 @
(empty_weight>5.5).
This suggestion also has better backward compatibility and it also
enables country defaults.
Drawback is that only one maxweight-restriction per way is possible.
Opinions?
martinq
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