Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Furnishings and Equipment (hierarchy name)
4. Tools and Equipment (hierarchy name)
5. equipment
6. [equipment by process]
7. power producing equipment
8. engines (power producing equipment)

Anotations

Scope note:

Internal-combustion engines in which a spray of fuel introduced into air compressed to a temperature of approximately 1000 degrees Farenheit (538 degrees Celsius), ignites at a virtually constant pressure.