upda - volu
- update procedure
- updraught
- upgrade
- uplift ratio
- uplock cylinder
- uplock latch
- upper advisory area
- upper air
- upper air area
- upper air movements
- upper airspace
- upper area control center
- upper atmosphere
- upper case
- upper control area
- upper flight information region
- upper information center
- upper level control area
- upper stage propulsion
- upper surface
- upper wind
- upper wing
- upper-air chart
- upper-air forecast
- upper-air observation
- upper-air sounding
- upper-air temperature
- upper-case letter
- upper-level anticyclone
- upper-stage rocket
- uppermost atmosphere
- uprated engine
- upslope fog
- upward current
- upward dihedral
- upward flight
- upward leg
- upward movement
- upwind approach
- upwind landing
