heli - high
- helicopter structure
- helicopter suppression
- helicopter timetable
- helicopter trainer
- helicopter wireframe
- helicopter-based minesweeping operations
- helicopter-borne
- helicopter-capable ship
- helicopter-standard vision
- helideck
- helideck technique
- helipad
- heliport
- helium
- helium bubble photograph
- helium driver
- helium gas transmission
- helium tunnel
- helium-bubble generator
- helium-bubble method
- helium-filled aerostat
- helium-filled balloon
- helium-filled envelope
- helmet
- helmet mode
- helmet pointing system
- helmet-canopy impact
- helmet-mounted display
- helmet-mounted projector
- helmet-mounted visual
- helmet-mounted visual system
- helmet-position detector
- Helmholtz equation
- Helmholtz free energy
- Helmholtz resonator
- Helmholtz theorem
- Helmholtz's law
- helo
- hemispherical dome
- Herbst maneuver
