maintenance of direction during advance

advance to and during the attack

during air-raids

during one's time as a prisoner of war

hold advance / hold (up) advance

advance in a different direction

direction of advance

contingency maintenance / special maintenance

depot maintenance (beyond O and I level activities, performed in an industrial-type facility) / D-level maintenance

maintenance checks / routine maintenance, scheduled tasks

maintenance idling (periodic running of engine for maintenance purposes)

organizational maintenance (O-level) (day-to-day work that standard airfield maintenance groups perform in support of airfield operations)

routine maintenance / scheduled tasks, maintenance checks

scheduled tasks / routine maintenance, maintenance checks

special maintenance / contingency maintenance

advance force

advance planning funds (APF)

advance warning

advance, flank, and rear guard

advance-warning satellite

axis of advance

fend off enemy's a advance

limit of advance (line)

main line of advance

maintain the momentum (of the advance)

route of advance

speed of advance

United Nations Advance Mission in Cambodia (UNAMIC)

United Nations Advance Mission in the Sudan (UNAMIS)

zone of advance

advance route

disrupt an advance

significant advance / breakthrough