Over 80% marine accidents occur owing to human errors of ship officers. This study investigates the situation wherein a deck officer is embarrassed by the fear of collision in a close-quarters situation (CQS), thereby failing to perform prescribed collision-avoidance measures. Increased perceived collision risks (PCR) due to beginner-deck officers' fear of collision threatens navigation safety in CQS scenarios.
This study investigates the influences of onboard career (OC), license rating (LR), and age on the deck officer’s PCR in CQS. To quantify the PCR, a head-on and crossing situations were simulated based on the International Regulations for Preventing Collisions at Sea. The heart rate variability of deck officers was measured when the own ship and target ship (TS) approaching each other at a speed of 10 knots until they collided from distance range of 2.5 nautical miles.
Results show that the mean PCR of deck officers at perceived collision risk bearing range (relative bearing) S4 (112.5˚~157.5˚) was highest. Next, PCR measurements were higher in the order of 090˚, 045˚, and 000˚.
Multiple regression analyses reveal that the OC and LR negatively influenced on the PCR; however, age had no effect on the PCR.
T-test results show that deck officers with OCs ≤ 4 years group was higher PCR than those with OCs ≥ 5 years. Deck officers with LRs of 4-6 class group was higher PCR than those with LRs of 2-3 class group. The results of this study are contributed to identify certain key cognitive collision risk factors that are required to improve marine navigation safety.
Based on the results, in a CQS with a risk of collision, the deck officer must special attention to the manoeuvre of the TS because the PCR of the deck officer increased significantly from the distance of 1.5 NM, it is recommended to take early avoidance action at least before that distance to prevent collision. Second, professional navigation training using a ship handling simulator should be strengthened specially for deck officers with OCs ≤ 4 years and with LRs ≤ class 4. This recommendation could expect prevent ship collision accidents by preventing human error due to panic and psychological stress and by increasing a deck officer’s ability to perform collision avoidance actions.
The Collision Avoidance Algorithm (CAA) has been developed to provide guidance for avoiding collisions in various CQS. The CAA can be use as an action guideline to prevent human error of deck officer and prevent ship collision.