Aircraft Positioning Elements

An assembly drawing must say where the drawn part sits on the aircraft. The positioning rule of the drawing standard (structural elements helping the reader position the part) reads that from two families of elements, and drawing_tools detects both in the view/annotations/aircraft/ subpackage — grouped by the question they answer, not by the shape they take on the sheet:

📐 Reference Lines

The dash-dot lines of the aircraft coordinate grid, each claimed by a label naming an axis and a value: X 6815, Y-670, Z 1565.8 (DERY-3760, DERY-3761).

Aircraft Reference Lines

➡️ Orientation Indicators

The arrow drawn with a bilingual caption naming an aircraft direction: AVANT APPAREIL / FRONT AIRCRAFT, HAUT APPAREIL / TOP AIRCRAFT (DERY-3759).

Aircraft Orientation Indicators

The two detections share their access pattern. Each is computed on a FeaturedView and aggregated on the FeaturedSheet and the FeaturedDrawing, and each has a companion overlay on the three levels, also stacked into plot_data_all_overlays:

Element	Property	Overlay
Reference line	aircraft_reference_lines	plot_data_aircraft_reference_lines()
Orientation indicator	aircraft_orientation_indicators	plot_data_aircraft_orientation()

See also

The script scripts/detect_aircraft_features.py in the repository reports both detections together, view by view, and opens their overlays on every sheet carrying either.