DETERMINATION OF REPAIRABILITY

Life rafts are considered beyond repair for any of the following reasons:

1. Porous fabric areas on tubes

2. Split or open tube seams

3. Leakage test failure resulting from other than a cut, tear, or puncture

4. Damaged or malfunctioning inlet valve, manifold, or oral inflation tube

5. Damaged or malfunctioning topping-off valve that cannot be corrected by replacement of the topping-off valve opening insert

6. Multiplace rafts (leaky bulkheads)

FUNCTIONAL TEST

Before functionally testing a life raft, you should make sure you have enough area to inflate

the life raft. Remember to take into consideration the inflated size of the raft; an LRU-15/A will take 20 times the area that an LR-1 requires.

To begin the test, you first open the carrying case and unfold the life raft. All life rafts have an inflation assembly, and by pulling an actuating cable, you automatically inflate the raft with CO2.

When you do this, the raft should inflate to

design shape, without evidence of restriction, in less than 1 minute. This is a CDI inspection point, so have a CDI inspector watching before you pull the cable. Once the raft is inflated, examine it for obvious defects such as cuts, tears, ruptured seams, and damaged manifold.

PULL CABLE PROOF LOAD TEST FOR MULTIPLACE RAFTS

The pull cable proof load test for multiplace rafts is done in conjunction with the functional test. Also, the test must be performed prior to placing an inflation assembly into service. First remove the inflation valve cover plate and remove the pull cable from the valve. Then apply a 50-pound pull force between the cable ball and the snap hook to determine if the cable is strong enough for the system.

Examine the pull cable for broken strands of wire, deformed snap hook, security of snap hook spring latch attachment, and loose or cracked swage fittings. If any damage is found, the pull cable is discarded and replaced with a new cable. The new cable is also tested. If the snap hook spring latch is loose, it may be repaired in accordance with instructions contained in NAVAIR 13-1-6.1.

If the pull cable passes this test, reinstall the cable. Refer to NAVAIR 13-1-6.1 for details of installation.

LEAKAGE TESTING

The only way that you can be sure that a life raft does not have a leak is to perform a leakage test. To test the LRU-15/A with a vented Ymanifold for leakage, you must ensure that either the manifold inlet is capped or an empty cylinder is installed and the manifold inlet is in the CLOSED position. Install an equalizer tube clamp. These procedures are necessary for this raft due to its design. The LRU-15/A has two flotation tubes; one is on top of the other. The equalizer tube allows C02 or air pressure to enter both tubes at the same time. If you fail to cap the inlet, you will not be able to hold the pressure within the flotation tube. If you don't use an equalizer clamp, you will blow up both flotation tubes.

NOTE: Flotation tubes must be tested separately to determine internal vertical bulkhead leakage.

All multiplace life rafts are filled with air pressure through the topping-off valves. The LR-1 is inflated through an oral inflation tube.

After you have reached the test pressure (table 6-1), shut off the air supply and wait 15 minutes.

Table 6-1.-Life Raft Test Pressures

Table 6-2.-Example of Temperature and Barometric Pressure Check .

Table 6-3.-Temperature Conversion Chart

After 15 minutes, adjust the air pressure if necessary. At this time you must record the temperature and barometric pressure. This is done because any drop or rise in temperature or pressure affects the pressure within the flotation tube. Allow the raft to remain undisturbed for a minimum of 4 hours. At the end of 4 hours, check and record the test pressure and again record the temperature and barometric pressure.

See table 6-2 for an example. By using the conversion charts in tables 6-3 and 6-4, you can determine the correct reading for your raft. If your test pressure is within limits, you are ready to deflate the raft and repack the assembly. If the raft should fail this test, you must determine the cause. Information on testing for leaks can be found in chapter 2 of NAVAIR 13-1-6.1.

CLEANING

As you work on survival equipment you find that cleanliness is very important. It gives the equipment a longer service life, and it reassures the aircrewman that he is using an operational piece of equipment. If he sees a dirty life raft, he may think it is old and that it might leak. To clean life rafts, prepare a solution of cleaning compound (MIL-C-25769) consisting of one part compound and three parts water. Apply the cleaning solution to soiled area with a spray or

sponge. Allow the solution to remain on the surface for several minutes, then rub with a soft brush or rag. Rinse the surface thoroughly with water and wipe with a cloth or sponge. Repeat this application until the surface is free from all solution. Dry the raft with a lint-free cloth, and apply a light coating of talcum powder.