What Deploys an Emergency Raft?
To begin the deployment of an emergency raft, you throw it out of the airplanes door or overwing. Once you tug on the painter cord, compressed gas is released from the reservoir through the aspirators which pull in the ambient air utilizing the venturi effect. After this, the raft will inflate in a matter of seconds.
Emergency rafts can also be deployed by using hydrostatic release units. These function by sealing the life raft container to the deck of the vessel you’re on. Once the vessel you were on starts to sink, the water pressure triggers the hydrostatic release units to sever the tie between the life raft and the deck of the vessel.
In general, these are the steps to take when using an aviation life raft:
- Make sure you have your life vest on.
- Collect any essential gear you may need to take with you on the raft.
- Remove your life raft from where it is being stored and place it by an open door.
- Hold onto a painter line or inflation lanyard.
- While holding onto the painter line or inflation lanyard, throw the life raft overboard.
- Pull the lanyard out until you’ve hit about six feet.
- Tug on the lanyard quickly and sharply to pull the inflator pin, which will begin the inflation process.
- After the inflation process is complete, board your life raft and erect its canopy if it has one.
This process may differ slightly depending on the brand of life raft you’re using.
How Are They Maintained?
Regular inspections are crucial to maintaining your life raft. Let’s explore what particular parts of a life raft you should inspect and what you should be looking for:
- Look for any tears in the raft.
- Next Service Date – check that the raft is within its service limits which will ensure all items are functioning properly.
- Check the gauge of the reservoir to ensure the unit hasn’t leaked.
Maintenance that requires a trained professional:
- Pressure testing the raft to ensure there are no leaks in it or no porosity in the fabric, also referred to as an Air Retention test.
- Check function of aspirators and pressure relief valves.
- Check all lights/batteries on the raft are working and ensure battery life will meet the life of the overhaul.
When Do Aircraft Life Rafts Need to Be Replaced?
While aircraft life rafts are highly durable, eventually, they can wear out due to usage or aging fabric/glue. Here are some of the signs that your life raft might need to be replaced:
- For corporate jet life rafts, ensure you have the correct capacity life raft for the number of passengers you have in flight.
- Aged life raft – any life raft over 15 years is susceptible to porosity in the fabric or leaks at the seams due to the age of the glue, it’s recommended these units be inspected annually.
- If they do not pass the CMM testing requirements the unit will no longer be serviceable and need to be replaced.