The basic functions of a helicopter helmet are to protect the user from impact, protect hearing and provide a platform for night vision goggles (NVG). We accomplish the impact protection by providing barriers between the wearer and the impact that mitigates the amount of force that passes into the user. The helmet provides hearing protection via ear cups with acoustic foams and accessories. The helmet uses both fixed and quick release connections between the visor cover and NVG mounts.
For a secure fit, wear the helmet with the chin strap and nape tightened until snug. It is important to wear a helmet of the proper size with an appropriate comfort liner thickness. Please see the section “Helmet Size Guide” to find what helmet size is appropriate. A helmet that is not the right size could be unsafe. If the helmet is too large, it may shift and may even be removed entirely during an event. If too tight, the helmet may cause pain and “hot spots.” Watch the Fitment Guide Video for assistance in fitting or see the section below.
Fitment Guide for the Kairos™ Retention Assembly
In order to properly don the helmet for the first time, ensure everything is loose. Undo the one-time cam locks and ensure the Boa® Closure System has all the tension released by pulling the dial, located on the nape, completely out. Make sure the ear cups are centered in the domes. Place your thumbs inside the ear cups and slightly spread the helmet.
Position the front edge of the helmet firmly against your forehead and rotate the helmet rearward and down onto your head. The front edge of the helmet should be sitting approximately one inch above your eyebrows. This ensures the front edge of the helmet doesn’t obscure your field of view and properly positions the helmet-mounted NVG Quick Disconnect for use with Night Vision Goggles.
A word of caution: Having too thick of a comfort liner installed in your helmet will cause the helmet to sit higher than two fingers and may cause discomfort. A comfort liner that is too thin will cause the helmet to sit lower than previously described. In both cases, the helmet may be uncomfortable and may cause your NVG’s to not properly adjust.
Now, grasp the buckle on the chin strap by the red tag. Reach in under your chin and try to touch the opposite side of the shell. As the buckle gets close, follow the hook side strap down until the magnet catches. You should hear an audible “click” when this occurs.
Be aware that there is a “ladder buckle” on your chin strap, ensure that the excess tail of the strap is not secured by the “ladder buckle” when adjusting for the first time. Once the strap is secured and if the “tag” end of the strap is through the buckle, it will be difficult to properly adjust.
To tighten, firmly pull on the tail end of the chin strap to attain a snug fit. You may need to adjust the position of the pad for maximum comfort.
Once you have the chin strap properly adjusted, secure the excess end using the “ladder buckle” and insert the remainder through the webbing on the bottom of the chin pad.
The Boa® Closure System is state of the art and is the most advanced closure system in the industry. To properly operate the Boa dial:
Ensure the dial is pushed all the way in. Tighten the system by turning the dial clockwise. As you tighten the Boa® dial, the earcups and nape will close in around the head, securing the helmet. Proper adjustment of the earcups will result in approximately 50% compression of the ear-seals. Securing the helmet should cause a distinct drop in external noise and feel slight to moderate pressure from the earcup seals. This will also cause the helmet to pull back and down, depending on how much the Boa dial is tightened. Turning left with tension applied to the nape loosens the retention assembly, or if preferred, pull the dial out completely to release all of the tension.
Once you have obtained the proper fit, lightly pull one of the cam lock straps towards the front of the head until taut. As you hold the cam lock strap taut, close and secure the cam lock. This process should not need to be repeated on subsequent donning, nor should it be released to doff the helmet. Repeat this process for the opposite side. Avoid over-tightening the cam lock straps; it may cause the nape or ear cup to be out of position. Your helmet is now, flight ready.
To remove the helmet: reach behind the neck and find the Boa® dial and turn counter-clockwise, or if desired, pull the dial out to remove all tension. It should only take a few “clicks” to the left on the Boa® dial to loosen the nape enough to doff the helmet.
Pull down the red tag on the chin strap buckle to release the chin strap. It will immediately fall away.
Place thumbs inside the ear cups and slightly spread the helmet. Push the helmet up and rotate it forward to properly remove it. Properly store helmet until further use.