NAVI 111 Week 1 - Different Electronic Navigational Aids (Flashcards)

A set of Question and Answer flashcards covering the 20 key electronic navigational aids introduced in Week 1 notes.

What navigational aid uses S-band (10 cm) and X-band (3 cm) radar, has a rotating antenna, and detects targets and obstacles to aid collision avoidance?

Radar — a detection system that uses radio waves to determine the range, angle, or velocity of objects; displays distance to land, vessels, floating objects, and obstacles.

What navigational instrument is non-magnetic, uses a fast-spinning disc, and automatically determines geographical direction?

Gyro Compass — a non-magnetic compass that finds the correct North position automatically, not affected by external magnetic fields.

What bridge navigational equipment maintains vessel steering automatically, allowing the crew to focus on other tasks?

Autopilot — an automatic system to control the rudder on the vessel.

What bridge system automatically acquires targets, plots speeds and courses, and helps avoid collisions?

ARPA (Automatic Radar Plotting Aid) — displays target positions and courses to assist collision avoidance.

What bridge device measures a ship’s speed and distance traveled from a set point to help determine ETA?

Speed & Distance Log Device — measures speed and distance traveled; used to calculate estimated time of arrival.

What instrument measures water depth by emitting sound pulses and listening for echoes from the seabed?

Echo Sounder — uses sound waves to determine depth by timing the return of echoes.

What computer-based navigation system uses electronic charts and can replace paper charts under IMO regulations?

Electronic Chart Display Information System (ECDIS) — digital navigation chart system.

What automated tracking system displays other vessels in the vicinity and helps pinpoint location?

Automatic Identification System (AIS) — automatic vessel tracking and identification system.

What international tracking system requires vessels to automatically transmit identity and position every six hours to improve maritime domain awareness?

Long Range Identification and Tracking (LRIT) — SOLAS-mandated tracking system.

What device provides the rudder angle, helping to control the rate of turn?

Rudder Angle Indicator — displays the current rudder angle.

What instrument continuously records vital information about ship operation, including a voice recording for at least the last 12 hours?

Voyage Data Recorder (VDR) — records voyage data and audio for investigations.

What navigational tool indicates how fast the ship is turning, typically in degrees per minute?

Rate of Turn Indicator — shows the turning rate of the vessel.

What system uses satellites to determine the ship’s location and assist in navigation and speed measurement?

GPS Receiver — Global Positioning System receiver.

What acoustic system allows an officer on an enclosed bridge to hear external sound signals from nearby ships?

Sound Reception System — acoustic-electronic aid for hearing signals on an enclosed bridge.

What system uses lights to indicate a craft’s position, heading, and status and has historical regulatory usage?

Navigational Lights — required lights indicating position and course; historical adoption by US (1838) and UK (1849).

What monitoring and alarm system detects if the Officer on Watch is unresponsive or inefficient and notifies others?

Bridge Navigational Watch & Alarm System (BNWAS) — monitors bridge activity and alerts if OOW cannot perform duties.

What device is the ship’s horn, typically in duplicate, with both air-driven and electrically operated units for use in poor visibility?

Ship Whistle — ship’s horn used for signaling in bad weather or low visibility.

What bridge equipment is used for ship-to-ship or ship-to-shore communication, with VHF for short range and MF/HF for longer range?

VHF & MF/HF — communications systems for routine, safety, urgency, and distress messages.

What bridge instrument records the course steered by the vessel automatically, with date and time stamps?

Course Recorder — records the vessel’s course for evidence of navigation.

What bridge system controls and changes the vessel’s course, including rudder actuators, steering gear, and tiller?

Steering System — the mechanism on the bridge for steering the vessel.