ratio of the mean axial flow velocity over the cross -section of upstream conduit to the acoustic velocity at the same location, teljesuunalise keskmise vookiiruse ülesvoolu juhtme ristlõikes ja akustilise kiiruse suhe samas kohas

ainesisaldus vees, mille ületamise korral vesi loetakse reostatuks, upper limit of the concentration of a substance in water which is not harmful for a certain purpose, límite superior de la concentración de una sustancia en el agua por debajo del cual no resulta perjudicial para un uso determinado, concentration au-dessous de laquelle un corps dissous n'est pas nuisible pour un usage donné de l'eau, верхний предел концентрации вещества в воде, при котором она безвредна для использования в определенных целях

the average distance from the leading edge to the trailing edge of the wing

an accident where two aircraft come into contact with each other while both are in flight