9.3 Inflatable Life Vests, Slide-Rafts & Survival Equipment

Inflatable Life Vests, Slide-Rafts & Survival Equipment

Overwater flight operations and emergency ditching procedures require specialized floatation devices, rapid-evacuation slide-raft assemblies, and long-term survival equipment. Nigerian Civil Aviation Regulations (Nig. CARs) Part 2 and ICAO Annex 6 specify strict mandatory carriage requirements for inflatable life vests, infant floatation cots, escape slides, slide-rafts, and survival kits on all commercial transport aircraft operating extended overwater routes.

Passenger & Crew Inflatable Life Vests

Aircraft life vests are constructed from high-strength polyurethane-coated nylon fabric designed to provide inflatable buoyancy in fresh or salt water.

Dual Inflation Chamber Architecture

Every certified aviation life vest incorporates two independent inflation chambers (twin cell construction). This dual-chamber design guarantees that if one chamber is punctured or fails to inflate, the secondary chamber provides sufficient positive buoyancy to keep an adult wearer's head above water. Each fully inflated vest provides a minimum of 35 lbs (155 Newtons) of positive buoyancy.

Color Coding Standards

To establish clear visual authority and emergency crew identification during a chaotic water evacuation, life vests follow strict international color standards:

• Passenger Life Vests: Bright Yellow.
• Flight Crew & Cabin Crew Life Vests: Flame Orange or Red.

+-------------------------------------------------------------------------+
|                    DUAL-CHAMBER CREW LIFE VEST                          |
|                                                                         |
|      [Oral Tube Cell 1]                     [Oral Tube Cell 2]          |
|             |                                      |                    |
|      +--------------+                      +--------------+             |
|      |  Chamber 1   |                      |  Chamber 2   |             |
|      +--------------+                      +--------------+             |
|             |                                      |                    |
|      [CO2 Pull Tab 1]                       [CO2 Pull Tab 2]            |
|                                                                         |
|   [Water-Activated Locator Light] ----> 8-12 Hour Battery Duration      |
|   [Signaling Whistle] -------------> Attached via Lanyard               |
|   [Color Coding] ------------------> Bright Orange / Red (Crew Only)    |
+-------------------------------------------------------------------------+

Inflation Mechanisms & Hardware Features

1. Primary CO2 Pull Tabs: Located at the lower hem of the vest. Pulling both red tabs sharply downward pierces two small $CO_2$ gas cylinders, inflating both chambers within 2 to 3 seconds.
2. Secondary Oral Inflation Tubes: Flexible rubber tubes with non-return valves located on the upper chest. Used to top up chamber pressure manually or inflate the vest if $CO_2$ cylinders fail.
3. Water-Activated Locator Light: Attached to the upper chest area. The light battery contains water-sensing contacts or a pull-plug. Once immersed in water, the battery activates automatically, emitting a continuous omnidirectional light of at least 0.75 candela intensity for 8 to 12 hours.
4. Signaling Whistle: Non-corrosive plastic whistle attached via lanyard for acoustic signaling in fog or dark conditions.

Infant Life Vests & Floatation Cots

• Infant Vests (Infants under 35 lbs / 15.9 kg): Specially shaped vests or enclosed Floatation Cots featuring harness straps, neck supports, and a tether line for adults.
• CRITICAL EVACUATION PROTOCOL:
  • Infant Vests/Cots: Must be inflated inside the cabin prior to reaching the exit door so parents can secure the infant safely.
  • Child & Adult Vests: Must ONLY be inflated at the exit door sill immediately before jumping onto the slide-raft. Inflating adult vests inside the cabin restricts movement through narrow exits and risks trapping passengers against the ceiling if the cabin floods with water.

Aircraft Escape Slides & Slide-Raft Systems

Commercial passenger aircraft are fitted with automatic inflatable slides or dual-purpose slide-rafts at all floor-level exit doors to facilitate rapid evacuation within the 90-second regulatory limit.

Door Arming & Disarming Mechanics (Girt Bar System)

• Arming (Doors to Automatic): Cabin crew manually connect the heavy metallic girt bar into brackets locked into the cabin floor threshold. When the door is opened while armed, the floor-anchored girt bar pulls the flexible slide pack out of its door container.
• Disarming (Doors to Manual): Crew disengage the girt bar from the floor brackets and lock it into stowage hooks on the slide pack housing, allowing the door to be opened normally for catering or boarding without deploying the slide.
• Cross-Check Protocol: Dual cabin crew verification ("Doors to Automatic and Cross-Check") verified visually and confirmed over the interphone system.

Automatic Inflation Dynamics & Manual Backup Handle

When an armed door is opened in an emergency, the falling slide pack pulls a mechanical inflation cable:

• Inflation Time: High-pressure compressed gas cylinders ($CO_2/N_2$) combined with ambient air aspirator tubes expand the slide-raft fully within 4 to 6 seconds.
• Red Manual Inflation Handle: If automatic inflation fails upon opening the door, cabin crew must immediately reach down and pull the red manual inflation handle located on the girt flap attached to the floor sill.

Slide-Raft Ditching Conversion & Detachment Protocol

On extended overwater aircraft, door slides function as self-contained survival rafts (Slide-Rafts). During a ditching evacuation, the slide-raft must be converted and detached from the sinking aircraft:

1. Board Passengers into Slide-Raft
               |
2. Lift Sill Girt Flap Cover
               |
3. Pull Girt Release Handle (Frees Girt Bar from Floor)
               |
4. Slide-Raft Remains Attached ONLY by Mooring Line
               |
5. Cut Mooring Line with Safety Knife (or Quick-Release Latch)
               |
6. Cast Off Slide-Raft & Deploy Sea Anchor

• Mooring Line Safety Knife: A hook-shaped safety knife is stowed in a dedicated pouch on the upper tube of the slide-raft near the mooring line attachment point. Crew members cut the heavy nylon mooring line to prevent the sinking aircraft from dragging the slide-raft underwater.
• Slide-Raft Survival Accessories:
  • Erectable Canopy: High-visibility yellow/orange fabric canopy supported by inflatable arch tubes, providing thermal protection against hypothermia and sunburn.
  • Sea Anchor (Drogue): Weighted fabric cone deployed into the sea to create hydrodynamic drag, stabilizing the raft against wind drift and wave capsizing.

Slide-Raft Pack Transfer & Removable Life Rafts

Nig. CARs 2.5.1.3(c) item 11 lists a slide raft pack transfer drill and a life raft removal and inflation drill among the aircraft-specific emergency drills a licence applicant must perform, so moving a raft is examinable in its own right, separately from deploying one at its own door.

• Why a transfer is needed. A slide-raft is only useful at a usable exit. If the door it belongs to cannot be used — fire outside, a sill below the waterline, a jammed door, or a failed inflation — the pack itself is still serviceable and must be taken to an exit that can be opened.
• How the transfer is made. The pack is released from its door container or floor stowage, carried or dragged along the aisle to the usable exit, and its girt and mooring attachment is connected to the fitting at that door before inflation. A packed slide-raft is heavy and awkward, so the drill is normally a two-crew task, or crew plus a briefed able-bodied passenger.
• Manual inflation. A transferred pack will not inflate automatically, because automatic inflation depends on the girt bar being anchored to the floor of its own doorway. The raft is thrown clear of the fuselage with the mooring line still attached, then inflated by pulling the manual inflation handle on the pack.
• Removable life rafts. Some aeroplanes carry separately stowed life rafts in overhead or ceiling compartments instead of dual-purpose slide-rafts. These are removed from stowage, carried to the exit, tethered, thrown out, and inflated by the same manual handle. Know which of the two systems your type rating covers, because the drill differs.

Aircraft Ditching Survival Kit Components

Every slide-raft carries a packed waterproof survival kit containing essential life-support items required under Nig. CARs standards: