The value is the uID of the referenced element, exactly as given in its uID attribute, e.g. the uID of the wing to which an engine pylon is attached. Any number of references can point to the same element.
References to symmetric components
A component with a symmetry attribute, e.g. a wing with symmetry="x-z-plane", results in two components: the component described by its data (defined side) and its mirror image (mirrored side), which is a component of its own. The symmetry attribute of a reference to such a component selects the side that is meant:
| Value | Referenced part of the component |
def | defined side only |
symm | mirrored side only |
full | both sides, i.e. the defined and the mirrored component (default) |
The attribute is only used in references to components with a symmetry attribute.
The figure shows an engine pylon whose parentUID references a wing mirrored at the x-z plane. With def, the pylon belongs to the defined side of the wing only, with symm to the mirrored side only, and with full to both sides.
<enginePylon uID="pylon">
<parentUID symmetry="symm">wing</parentUID>
...
</enginePylon>Side appended to the uID in older datasets
Older datasets often append the side to the referenced uID instead, e.g. wing_symm for the mirrored side of the wing wing or engine1_def for the defined side of engine1. This is not intended and must not be used: the string does not match the uID of the referenced element. Reference the uID unchanged and select the side with the symmetry attribute, as in the example above.
<enginePylon uID="pylon">
<parentUID>wing_symm</parentUID>
...
</enginePylon>