Your primary lens should be the 18-55mm. Helicopters have very few air restrictions and therefore will be getting close to the landscape. The wide angle will also reduce blur from vibration and movement.

A circular polarizer will only be needed if sunny. Skip it on a cloudy day to keep your shutter speed high. Only exception is if your shots are getting destroyed by reflections clipping in your shots.

If it's a doors-open flight, invest in a wrist strap. You'll be amazed by the photos you can capture with getting the camera out the door and capturing the side of the helicopter, but it's a moot point if your camera ends up part of the landscape below. Don't worry too much about wind, though, it's not as bad as you would think and you can comfortable get your hand 1-2 feet out and for a quick shot. Just get a wrist strap.

Hood would be helpful since cheaper lenses don't handle flair well. Take it off if the camera is going out into the wind.

If you're uncomfortable with a bunch of settings, sport mode is an easy fix. It will give you a wide aperture for a fast shutter speed.

Be mindful if when the helicopter is moving and especially when it is not. Your best opportunities are when it stops moving. Vibration increases slightly in a hover, though, so don't think you can slow down your shutter. When moving quickly, you may find yourself having to pan your shots at longer focal lengths. This is a sign that your shutter is too slow, but you'll save yourself some quality as opposed to not panning.

Side note: use the helicopter as a prop for some of your images! This is a great "wow" factor since it provides perspective. Army aviation specialist, photographer, and licensed pilot here. You hit a favorite topic of mine :)