With take off and landing sometimes resembling a roller coaster ride, and with more vibrations and exposure to turbulence than in a plane, it's not surprising that those prone to motion sickness can become unwell very quickly indeed in helicopters. And in such a confined space, if one person gets sick it can easily trigger a chain reaction...
Helicopters have a swooping motion (that you'll either love or hate!) and can change direction suddenly with sideways movements and occasional rapid changes in altitude. All this can add up to serious spatial disorientation, particularly at night when your eyes will struggle to find any reference point.
But don't discount that Hawaii helicopter sightseeing flight, or heli-skiing trip just yet.
This is a situation where medication may not be your friend. Most meds will make you drowsy, and that's the last thing you want on a sightseeing flight, or when preparing to ski. Be wary unless you have successfully used that particular medication before. See Motion Sickness Medication
for information on over-the-counter and prescription medications.
First of all, when booking your flight, it is crucial to ensure that your seat will be a forward-facing one. This will not be a problem with most sightseeing flights, but it may be an issue on heli-skiing trips, which sometimes use helicopters with benches fixed along the sides. Ask whether it is possible to sit up front next to the pilot. Just as in a car, you are less likely to get sick in the front of the helicopter.
If you are making a booking for later that same day remember to ask about wind speed and weather conditions. Is it likely to be a rough ride? If the answer is yes, you may wish to reconsider your booking.
And take the time to introduce yourself to the pilot prior to the flight. Explain to him or her that you have a tendency to motion sickness. As it's generally the pilot's job to clear up after any sick passengers, your warning will make an impression and ensure that he or she goes easy on the turns and keeps things as smooth as they can (some pilots do like to show off a little!).
Fuel fumes can trigger nausea, particularly on a hot day, so when boarding try to stay up-wind of the helicopter.
NB: NEVER approach a helicopter from the rear, the tail propellers can be deadly. Always wait to be escorted by a crew member.
Once on board, try to relax into your seat. Holding your body stiffly is likely to bring on dizziness. Move your head around as little as possible and focus on the horizon (no looking down if you feel at all queasy!). Breathe slowly and evenly and don't hold your breath, or take sudden intakes of breath - easy to do if you're nervous, or when the helicopter makes an unexpected turn. If you are traveling with a friend, chat with them - talking regulates your breathing.
I've come across the suggestion that you should distract yourself by concentrating on taking photos. Personally I think using a camera would make me feel ill right away, but others may find that it does indeed help. If you do decide to try it, you'll be better using a camera with an LCD screen, rather than holding the camera to your face and peering through the viewfinder.
Take regular sips from a bottle of water, or suck peppermints, or other candies. This is particularly helpful on take-off and landing.
The noise of the propellers may be an issue if you're sensitive. Sometimes you'll be provided with noise-canceling headphones, but it's a good idea to take ear plugs with you.
Finally, think positive. Many people report that on gloriously scenic flights there is so much to look at that they don't even think of getting sick!