LAR-5

LAR-5 (Lung Automatic Resuscitator) is a type of rebreather used primarily for underwater diving and military operations. It was developed by the United States Navy in the 1960s as a compact, lightweight breathing apparatus that could be used for long-duration missions.

History

The LAR-5 was developed in response to the need for a compact, lightweight rebreather that could be used for long-duration underwater missions. The design was based on the earlier LARU (Lung Assisted Resuscitation Unit), but with several improvements to increase its efficiency and reliability.

Design

The LAR-5 is a closed-circuit rebreather, meaning that the user's exhaled breath is recycled within the system rather than being vented to the surrounding environment. This makes it ideal for stealth operations, as it produces no bubbles that could reveal the diver's location.

The rebreather uses a mixture of oxygen and helium known as heliox to provide breathable air. The helium reduces the risk of oxygen toxicity, which can be a problem with pure oxygen rebreathers.

Operation

To use the LAR-5, the diver first fills the rebreather's gas cylinder with the appropriate heliox mixture. The diver then dons the rebreather and adjusts the breathing loop to fit comfortably. Once underwater, the diver can adjust the rebreather's settings to maintain the optimal gas mixture for the current depth and workload.

Applications

The LAR-5 is used primarily by military divers for long-duration, stealth operations. It has also been used in scientific research and underwater archaeology, where its long duration and lack of bubbles can be advantageous.

See also

• Rebreather
• Underwater diving
• United States Navy