Marine Institute Memorial University of Newfoundland Liferaft Operational Performance James Boone – Offshore Safety and Survival Centre.

Marine Institute Memorial University of Newfoundland

Liferaft Operational PerformanceJames Boone – Offshore Safety and Survival Centre

• Inflatable liferafts in use since WWII

• First recognized in SOLAS in 1960

• Increasing numbers of inflatable liferafts

• Increasing size of inflatable liferafts– 35 person davit-launch was “large”

– 150 person inflatable liferafts now common

• Liferafts can provide rapid evacuation (MES)

• Evacuation not complete until liferaft is cleared from side of vessel by paddling or towing

Liferafts:Background

• Towing performance specified in CALM conditions– Standardized test conditions

– Easily repeatable

• Capable of being towed at 3 kts [Res. MSC.48(66)]

– Fully loaded

– Sea anchor streamed

• Tested with 1 km tow [Res. MSC.81(70)]

• Tow force recorded at 2 & 3 knots

• Tow force supplied on type approval certificate

Liferafts:Towing

• Lifeboat, Rescue Boat or FRB

• Must tow at 2 kts in calm weather– a 25 person liferaft, or

– the largest liferaft carried on vessel

• Towing performance specified in CALM conditions

• Emergency response requires performance in prevailing conditions

What are the weather limits for towing performance?

Liferafts:Towing Craft

Funding• National SAR SecretariatProject Sponsor• Canadian Coast Guard – Marine SAR

Project Partners• Marine Institute – Offshore Safety & Survival Centre• National Research Council – Institute of Ocean Technology• Memorial University – School of Human Kinetics

Liferaft Operational Performance: Project Background

• $2.1M total budget over 3 years

• Investigate aspects of liferaft performance while being towed

• Focus on passenger vessel industry

• Full-scale and model scale trials

• Human performance testing in controlled motion environment

• Results intended to inform standards development and training

Liferaft Operational Performance: Project Background

Full Scale Sea Trials:16 and 42 Person Liferafts

• Proof of concept

• Select raft configurations

• Logistics

• Develop Instrumentation

• Collect Data for Scale Model Development and Validation

Full Scale Trials:16 and 42 Person Liferafts

Wave distribution

observed in full

scale trials

Full Scale in Wave Tank :16 person raft tow force prediction

Predicted Tow Force in Grand Banks Wave Spectra extracted from

NRC Report

TR-2006-01

An Empirical Method for the Estimation of Towing Resistance of a Life Raft in various Sea States

Mak, L.M., Kuczora, A., Simões Ré, A

Full Scale in Wave Tank :16 person raft towing observations

Preliminary Analysis Suggests:

• Mean tow force and raft heave increase with floor inflation, drogue deployment, even weight distribution and increased tow speed. Floor inflation also increases tow force variation. Raft heave tends to decrease with tow speed.

• Even weight distribution and drogue deployment increase raft surge, while floor inflation decreases raft surge.

TR-2006-01

Mak et al.

Model Scale Tests Ongoing:16 and 42 person rafts

NRC IOT Lead

- António J. Simões Ré

Objectives

- Match full-scale weather

- Validate scale model

- Use validated model to predict weather limits for liferaft towing performance

Model Scale Tests Pending:150 person raft

Full Scale Trials:150 Person Liferaft

Sept 2006

Full Scale Trials:150 Person Liferaft

Full Scale Trials:Data Acquisition

Human Performance Trials:

MUN School of Human Kinetics Component Lead by Dr. Scott MacKinnon• Raft as motion environment• Motion effects on survival task performance• Motion effects on cognitive task

performance

Human Performance Trials:Example Task• Painter cut in

calm and waves

Conclusion of Work:Tasks Remaining

• Analysis of full scale data• Completion of scale model testing and analysis

of data• Integration of data and development of

analytical model for predicting liferaft towing performance in weather

• Use human factors studies and predictions from analytical tool to prepare a training needs analysis for liferaft towing and use

Conclusion of Work:Outputs Pending

• Conduct a workshop to communicate and discuss the results of liferaft operational performance study

• Recommend changes to liferaft and towing craft standards and certification based on use of a validated liferaft performance evaluation method/tool

• Recommend changes to training standards for liferaft use based on engineering performance evaluations and human factors analysis

Further Information For additional information including dates

and agenda for the upcoming project workshop tentatively scheduled for March 2007 – please contact:

James Boone or Robert Rutherford

Offshore Safety and Survival CentreMarine Institute of Memorial UniversityPO Box 4920 St. John's, NL Canada A1C 5R3

[email protected]

[email protected]

Thank you for your time