Simulator sickness

July 4, 2011 by Tim McAdams

Simulator sickness is a form of motion sickness caused by physical and/or visual motion in a simulator. Compared to motion sickness, the symptoms tend to include more visual disturbances than gastrointestinal issues. Symptoms include dizziness, nausea, eye strain, feelings of warmth, headache, disorientation, and fatigue. What causes this is a conflict between the vestibular, visual, and proprioreceptive senses and pilot’s expectations based on past flight experience. As such, pilots with high amounts of actual aircraft experience are more susceptible to simulator sickness than students with little flight time in the actual aircraft. Flight time aside, some pilots are able to adapt very quickly to simulator training and others have a more difficult time.

Any flight simulator has the potential to cause simulator sickness, however rotor wing simulators are known to cause higher rates of simulator sickness compared to fixed wing ones. Helicopters simulators generally have larger visual areas and this increases the potential for a conflict. Some maneuvers require hovering close to objects which amplifies any discrepancy between what the pilot sees and feels versus expectations. 

Several techniques and restrictions have been developed to help reduce this phenomenon in helicopter pilots:

  • Limit session duration to 2 hours daily
  • Having the pilot close their eyes before freezing the visuals or repositioning the aircraft
  • Limit hover and autorotation training until the pilot can adapt to the simulator
  • Careful maintenance to eliminate any optical distortion caused by misaligned or poorly calibrated optics
  • Maintain health and be well rested
  • Insure adequate ventilation and cooling in the simulator

Flight simulators are a safe and cost effective alternative to actual flight and are an invaluable tool for training. As helicopter pilots are exposed to simulators more, the propensity for simulator sickness decreases. As technology and computer processing power continue to evolve helicopter simulators will also improve.

10 Responses to “Simulator sickness”

  1. Terry Simpkins Says:

    Great article. If you ever get to the San Diego area stop and spend some time in the FLYIT Professional Helicopter Simulators.
    We have have alot of hands on experience and have a lot of solutions to the simulator sickness issues. Over the last 12 years of demonstrations and training we have only had 2 people have simulator sickness and it was totally visual. They were both helicopter pilots.
    They also adapted very quickly after they had their simulators to use regularly.

  2. Ben Says:

    Thanks for the nice basic summary and guidelines. Congrats for refraining from adding all the usual unproven countermesures. Recommend including some of your lit. sources (e.g., Kennedy; McCauley) from which your comments were drawn, perhaps simply as “further reading” at the end.

  3. Don Diedrich Says:

    I am a retired industrial designer that worked at both Beechcraft and Swearingen early in my career and I have been working on a low cost, 5-DOF motion platform for over 6 years that can fit under most “stationary” simulation cockpits. The one degree of freedom that I decided to leave out of my initial product release is SWAY, as it is the most difficult to create within a confined area and I feel it is the least of simulated motion responses required during normal flight of fixed wing aircraft operation. I am presenting a white paper at the upcoming AVSIM FANCON in Washington, D.C. in the late fall. The title of the paper is “Making all the Right Moves” and will cover in detail the what I feel are the salient combinations of physical motion responses to realtime flight data input and visual cues received by the pilot(s).

  4. Helicopter License Says:

    Is there a physiological difference between motion sickness in a simulator and that which someone experiences when in an actual helicopter? You did a great job explaining the hows and whys of simulator sickness, and it makes me wonder if this applies just to simulators or in the sky as well. Great post, by the way!

  5. Tim McAdams Says:

    That’s a good question and I do not know the answer. If someone does, please comment.

    Tim

  6. Don Talleur Says:

    In regard to Helicopter License’s question about the difference between simulator induced sickness and motion sickness in the actual aircraft, I’d have to say yes, there is a difference. At the very minimum, the cue conflict which induces SIS is often continual in a sim that lacks the correct motion cues for the visual information presented, whereas in the aircraft, cue conflict is often transitory and does not last, allowing the pilot to regain normal cue alignment (so to speak). That is to say, in the aircraft, the conflict is generally the result of head movement out of the plane of motion of the aircraft; the semi-circular cannals are sensing motion in a direction different from what is actually occuring. In the Sim, the semi-circular cannals are sensing the motion induced by the sim, but the visually depicted information does not jibe with the simulated motion, hence the conflict. Some amount of simulator induced motion conflict seems inevitbale, as it is difficult to simulate all three axes of motion, as well as acceleration on all three in a completely realistic way.

  7. Helicopter Licenses Says:

    Thanks for the nice summary! I personally do not suffer from simulator sickness but many of my friends do!

  8. airplane simulator Says:

    airplane simulator…

    [...]AOPA Hover Power » Blog Archive » Simulator sickness[...]…

  9. cfa Says:

    I wish to show appreciation to this writer for bailing me out of this type of predicament. Because of looking out throughout the search engines and meeting proposals which were not beneficial, I believed my entire life was gone. Living without the presence of approaches to the difficulties you’ve solved through your entire post is a serious case, as well as the kind that could have badly affected my entire career if I had not noticed your blog post. Your primary ability and kindness in maneuvering every aspect was excellent. I am not sure what I would have done if I had not come upon such a point like this. I can at this moment relish my future. Thank you so much for your skilled and effective guide. I won’t hesitate to suggest your web site to anyone who needs to have support about this issue.

  10. tips for men how to last longer Says:

    This is a very good tip especially to those fresh to the blogosphere.
    Short but very accurate information… Many
    thanks for sharing this one. A must read article!

Leave a Reply

*