TERMIUM Plus^®

Fiche 1,  Justifications,  Anglais

Record number: 1, Textual support number: 1 CONT

In a skidding turn, the gyro precesses towards the inside of the turn. After return on the aircraft to straight and level flight, the instrument shows a turn in the direction of the skid. In a normal turn, the gyro precesses towards the inside of the turn. The precession error is quickly corrected by the erecting mechanism.  2, fiche 1, Anglais, - erecting%20mechanism

Record number: 1, Textual support number: 2 CONT

The only really tricky part of the attitude indicator is its erecting mechanism. When power (vacuum) is first applied to the instrument, the mechanism quickly erects the gyro spindle to plumb-vertical in order to align the artificial horizon with the natural horizon. In flight, the erecting mechanism continually compensates the gyro for precession errors in order to keep it aligned throughout the course of a long flight. The design of the erecting mechanism is quite clever. In an air-driven attitude gyro, there are "pendulous vanes" suspended from pivots attached to the lower portion of the sealed gyro housing, one vane for each exhaust port. The vanes are positioned so that, when the gyro is erect, each vane half-covers its associated exhaust port. If the gyro tilts so that its axle is not plumb, the pendulous vanes shift so that one exhaust port is more-than-half-covered and the opposite exhaust port is less-than-half-covered. The resulting imbalance of discharge air exerts a force on the rotor housing at right angles to the direction of tilt, causing the gyro to precess to the erect position. As soon as the gyro is erect, the pendulous vanes return to a balanced condition to remove the precessing force. Pure magic! The erecting mechanism can erect the gyro quite quickly at initial power-up because the gyro doesn't exhibit much gyroscopic rigidity at low rotor RPMs. Typically, the horizon bar becomes level within the first 10 or 15 seconds, and then its oscillations (caused by precessional nutation of the gyro) are damped out within a minute or so as the rotor comes up-to-speed.  3, fiche 1, Anglais, - erecting%20mechanism

Fiche 1,  Justifications,  Français

Record number: 1, Textual support number: 1 CONT

Dans un virage dérapé, le gyroscope «précesse» du côté du virage. Une fois l'avion revenu au vol rectiligne en palier, l'instrument indique un virage dans la direction du dérapage. Dans un virage normal, le gyroscope «précesse» du côté du virage. Le mécanisme de redressement du gyroscope corrige rapidement l'erreur de précession.  1, fiche 1, Français, - m%C3%A9canisme%20de%20redressement

Record number: 1, Textual support number: 2 CONT

Description d'un Épervier [drone] [...] d. Le gyroscope vertical: Dans ce cas, les deux axes, ROLL et PITCH sont terminés par les potentiomètres qui détectent les écarts de positions angulaires du corps par rapport aux horizons roll et pitch. Les mécanismes d'érection ne sont prévus que pour maintenir la verticalité parfaite de la masse en rotation.  6, fiche 1, Français, - m%C3%A9canisme%20de%20redressement

Record number: 1, Textual support number: 1 OBS

Horizon gyroscopique [...] La verticalité de l'axe de toupie [delta] est approximativement assurée par un érecteur (mécanique, électro-mécanique, pneumatique) produisant une raideur en quadrature de signe convenable.  7, fiche 1, Français, - m%C3%A9canisme%20de%20redressement

Fiche 1,  Justifications,  Espagnol