Reduced Gravity Flight Operations

Aerospace Physiology, Spatial Awareness Briefing

ScopeThe nominal environment is similar to

commercial aviation with a few exceptions.Qualified Non-Crewmembers can expect the

same physiological responses and hazards as commercial aviation.

The aerobatic maneuver can induce physiological responses not generally experienced outside of this environment.

Research Experiment operations may present increased inherent hazard or exposure.

OverviewBasic physiology associated with moderate

altitude aviationNominal and off-nominal conditions

Altitude CountermeasuresBasic physiological response to parabolic

flightPhysiological Countermeasures

GoalsEnsure Qualified Non-Crewmembers have a

basic understanding of their physiological response to the predicted environment.

Ensure Qualified Non-Crewmembers have a basic understanding of simple countermeasures.

Ensure Qualified Non-Crewmembers have the tools to focus on their research and complete mission safely and successfully.

Hypoxic HypoxiaHypoxia: A state of oxygen deficiency in the blood,

tissues , and cells sufficient to cause an impairment of mental and physical functions.

Any condition that interrupts the flow of oxygen to the lungs:Breathing air at reduced pressure (above 10,000’)Breathing smoke/fumes/research experiment gassesChoking/DrowningMedical problems

Emphysema Asthma Pneumonia

Signs are objective and can be seen by an observerIncreased rate and depth of breathingCyanosisSlurring of speechPoor coordinationMental confusionEuphoriaBelligerenceLethargy Unconsciousness

Symptoms are sensations a person can detect while in a hypoxic state (in this case)

Blurred visionTunnel visionAir HungerHot & Cold flashesEuphoriaNumbness Tingling

ApprehensionNauseaDizzinessFatigueHeadacheBelligerence

Insidious Onset

The most dangerous aspect of hypoxia is its insidious onset

Time of Useful Consciousness[TUC]The period of time from the loss of oxygen

supply or exposure to an oxygen poor environment to the time when deliberate function is lost.

TUC or Effective Performance Time [EPT]Slow decompression

FL430: 9-12 secFL350: 30-60 secFL280: 2.5-3 minsFL250: 3-5 minsFL180: 20-30 mins

Rapid decompressionFL430: 5 secFL350: 30 secFl280: 90 secFl250: 2.5 minsFL180: 10-15 mins

Factors Affecting TUCAltitudeTime at AltitudeRate of ascentActivity Level Physical fitnessDietFatigueTemperatureHuman Factors

TreatmentGet on 100% oxygenCheck equipmentControl your rate and depth of breathingLet a crewmember knowPilot will descend aircraft below 10,000 feet

as soon as practical

HyperventilationA condition where the rate and depth of breathing is

abnormally high causing an excessive loss of CO2 in the bodyIncrease in pCO2 stimulates breathing

Inadequate respiration or high CO2 levels Physical exertion

Decrease in pCO2 reduces breathing

CausesEmotional

Fear Excitement Anger

Hypoxia

HyperventilationSigns

TetanyUnconsciousness

SymptomsTinglingDizzinessHot & Cold flashesVision impairmentFaintingMuscle tremorsNauseaNumbness

PreventionDon’t PanicControl your rate and depth of breathing

Pause between inhale and exhaleTalk out loud

Trapped GasExpanding gas inside the hollow body cavities

that cannot escapeAreas affected

EarsSinusesG.I. tractTeeth

EarsMiddle ear

Problems usually occur on descent, rarely on ascent

Causes: Head cold/upper respiratory infection Blocked or constricted Eustachian tube Failure to valsalva properly

Middle EarSymptoms:

FullnessDull hearingPain

Prevention:Do not fly with a coldDuring ascent: yawn, chew, swallow, rock head

side to sideDuring descent: valsalva

Valsalva1. Pinch both nostrils closed and tilt head up

10 deg2. Take a breath of air and close mouth3. With mouth and nose shut, blow as if you

were trying to blow your nose.

Note: the maneuver should be short in duration but sharp. Do not overpressure the ear!

Sinus ProblemsUsually happen on descent but can happen

on ascentCauses:

Cold, URI, etcAllergiesSmokingChlorinated pools

SymptomsSudden severe painReferral pain in upper teeth

Sinus ProblemsPrevention:

Don’t fly with a cold or congestedTreatment:

ValsalvaSee flight surgeon

Gastrointestinal [GI] TractCauses:

Decreased atmospheric pressureDiet/digestive ProcessSwallowed air

SymptomsDiscomfortDistentionCrampsPain

GIPrevention

Proper diet and good eating habits

Avoid carbonated drinks

Avoid chewing gum or other that may cause you to swallow air

TreatmentBelchPass flatusMassage lower

abdomenSee flight surgeon

TeethCauses:

Untreated dental problemTrapped pocket of air after dental work

Symptom:Pain on ascent

Treatment:See flight surgeonSee your dentist

Spatial Awareness and Motion Sickness Prevention

DisorientationThe inability to determine one’s true body

position or motion; a condition that can occur when sensory inputs disagree with one another or do not match up with the actual motion or position.

Organs of EquilibriumVision (eyes)VestibularProprioceptiveOrientation and body responses

Vestibular ApparatusSemicircular canals detect rotationThe Otolith Organs detect direction and

intensity of Gravity and g-forces.

Semicircular CanalsTrue sensation False sensationNo turnAccelerating turn (right)

Sense of turning clockwise

Constant turnDecelerating turn (right)

Sense of turning counter clockwise

Semicircular canals are stimulated by Angular Accelerations

Otolith OrgansTrue Sensation False SensationTilt forwardUprightTilt backward

Forward accelerationSense is tilt backwards

Centripetal acceleration Sense is upright

Proprioceptive Sense(‘seat of the pants’)

While we are in contact with the Earth, the pull of Gravity squeezes pressure sensors in the various portions of the body, thus telling us in which direction the Earth is.

In parabolic flight, however, g-forces in other directions make the proprioceptive sense unreliable.

The Visual SystemThe Visual System provides the strongest and

usually the most reliable orientation information during flight.

Causes of Motion SicknessSensory conflictStressorsErratic head movementPre-existing illnessDietUnusual environmentLack of visual cuesPoor ventilation

Motion Sickness SymptomsIncreased salivation and swallowingNausea and vomiting or retchingSleepiness, fatigue, or weaknessWarm or cold sweatFlushing of the skinPallorHeadache (usually frontal)Dizziness

Prevention of Motion SicknessProper posture during flightEliminate or reduce self imposed stressMaintain hydrationEat before flightAvoid erratic head movements (especially in

high g)Well restedPrescription anti-motion sickness medications

Treatment of Motion SicknessRemove from provocative environmentStop provocative movements or activitiesCool downIsolate senses (i.e. close your eyes)Prescription anti-nausea or anti-emetic

medication

QUIZ1) Hypoxia can be a result of:

a) Depressurization of the cabin at altitudeb) Breathing smoke/fumes or research gassesc) Both of the above

2) The most dangerous aspect of Hypoxia is:a) Insidious Onsetb) Hot & Cold Flashesc) Cyanosis

QUIZ3) How many minutes of useful consciousness

would you have if the cabin suddenly lost pressure at cruise altitude?

a) 3b) ½c) 10

4) What area is affected by pressure change?a) Earsb) Sinusc) GI tractd) All of the above

Anti-Motion Sickness GuideResearchers have intensely studied motion sickness and

its causes for many years. How and why motion sickness occurs remains hotly debated. However, some things are clear:

1. Motion Sickness is related to mismatch between the senses (inner ear,

vision, etc.).

2. In some people, as the brain adapts to the changes in the environment, the

brain produces nausea and vomiting as a side effect of the process.

3. The stronger the motion, the harder the brain has to work and the greater

the chances for motion sickness.

4. Anyone can suffer from motion sickness if placed in the right environment.

What we do know1. In a given motion environment, motion sickness will only occur if the motion is severe enough.

2. The amount of motion required for motion sickness is different for each individual and for each

type of environment.

3. If the amount is way over the required level, motion sickness can develop rapidly; lower, it may

take hours for symptoms to develop.

4. Anti-motion sickness medications work by decreasing your sensitivity to motion.

Known Environment1. Moving around a lot while in a motion environment increases the amount of

motion your brain must process.

2. Although looking out the window at the horizon can help your brain process

the sensory information in some cases, looking out the window of the Zero-G

aircraft does not help.

3. Approximately 30% of flyers are insensitive to the type and amount of motion

experienced during parabolic flight and do not get sick on that flight.

4. Approximately 5-10% of flyers are very sensitive to parabolic flight in the

Zero-G aircraft.

5. The remaining 60-65% of flyers have moderate sensitivity to motion of

parabolic flight. For these people, how they behave during flight really

affects whether they will develop motion sickness or not.a. There is not a good way to predict how you will do during parabolic flight.

Prepare for your flight

1.The day and night before:a.Get plenty of rest the night before.b.Do not engage in rigorous athletic activities

within 24 hours of flight.c.Drink plenty of liquids to make sure your body is

well hydrated.d.Do not drink alcohol within 24 hours of flight.

People who drink alcohol are often dehydrated the next day. Alcohol also effects the brain’s ability to adapt to new motion environments which leads to worse motion sickness.

Prepare for your flight (con’t)2. The morning of the flight:

a.Eat a light breakfast at least two hours prior to flight (e.g. cereal). Do not overeat. Do not fly on an empty stomach.

b.Avoid eating food that may be irritating to your stomach. Do not eat greasy or spicy meals (e.g. bacon, omelets, etc.).

c.Wear light weight clothing (shorts, T-shirt) under your flight suit. It is better to be too cool than too warm.

d.Drink plenty of non-carbonated fluids to make sure your body is well hydrated. Water is the best fluid to drink.

Preventing motion sickness

During parabolic flight (High–g)

1.DURING THE 1.8G PULL-OUT PHASE (LASTS ABOUT 18-21 SECONDS)a.Body Position:

i. Keep the entire body as still as possible (do not strain, just relax in

place).

ii. The best body positions are either lying flat or sitting with your back

against the cabin wall.

iii. Flyers that lie flat on their back develop less severe motion sickness.

iv. Sitting may be required when performing projects that require

constant observation.

v. Use the position that is most comfortable. Feel free to experiment

with different orientations of sitting and lying.

Preventing motion sickness Con’tDuring parabolic flight (High–g)

b. Activity:

i. Do not nod, move or shake your head in any way. Minimize fast

head movements.

ii. Do not move around.

iii. If you must move around because of your experiment, staying

in a seated position and sliding around using your hands while

keeping your head still is best.

iv. Relax during this portion of the flight. Straining or exerting

yourself can cause motion sickness to develop.

v. If you must perform tasks during this period, do not move your

body to face the tools or equipment.

Transition1.During the transition from 1.8g to

microgravity (lasts about 3-5 seconds):

a.Keep still

b.Wait until after the transition is complete to begin

moving (you will feel the difference). Sparing the

extra few seconds will make a big difference for you.

c.Smoothly re-orient your body to face your

experimental activities.

d.Do not turn, nod, or bend your neck while moving.

Micro-g1.During the microgravity period (last 18-24

seconds):a.Body Positions:

i. Always keep your head and neck stiff like you are

wearing a neck brace.

ii. Never turn, bend or shake your head separate from

body.

iii.Keep yourself in an upright orientation.

Do not face upside-down. Especially at first. This can be quite disorienting

Micro-gb. Activity:

i. At first, keep your activities to a minimum to allow your body to

adjust to parabolic flight.

ii. Hold on to the restraints to keep stable

iii. Relax! You have plenty of time to experiment with microgravity

during the flights.

iv. Use only smooth and slow body movements.

v. Use the objects and restraints around you to help you move around.

vi. Do not kick or flail around.

vii. You may carefully and gradually increase your activity level if:

1. You are feeling fine.

2. You have become accustomed to floating, and know how to use the foot

restraints.

3. You have completed your required experiments.

Do not interfere with other people’s experiments or activities

Transition1.During the transition from microgravity to 1.8g (lasts

about 3-5 seconds):a.When you hear the call, “30 low”, or “feet down”:

i. Stop what you are doing.

ii. Smoothly orient yourself so your feet are towards the floor.

iii. Make sure there are no people or equipment under you.

iv. Gently let the gravity pull you towards a clear area on the floor.

v. Allow yourself to gently fall into your most comfortable 1.8g position.

vi. Use your hands, feet and body to push yourself into the right position.

vii.Always keep your head still and stable relative to your body.

viii.Once you are in a relaxed position, ride out the remainder of the 1.8g

period without moving your body or head.

Turnsa.While the aircraft is turning, between sets

of parabolas:

i. The plane will enter the turn after a high-G pull-out.

Do not move until the pull-out is over.

ii. Once the pull-out is over, and the turn has begun,

rest a few moments until your body is used to the

stable gravitational force.

iii.After a few moments of adjustment, you may walk

about the cabin like normal without difficulty.

Symptomatica. If you do start feeling motion sick:

i. Limit all of your activity.

ii. Hold firmly onto available restraints.

iii. Keep yourself upright during microgravity.

iv. Do not turn, nod or shake your head at all.

v. Do not look out the window.

vi. Keep your eyes open.

vii. Only look at objects that are right side up.

viii.Rest quietly in your most comfortable position during the 1.8g pull-outs.

ix. Have a motion sickness bag open and sticking out of each of your upper

flight suit pockets.

x. If the sickness goes away with rest, you may return to activity.

Onseta. If you do get motion sickness:

i. Continue to restrain yourself to the cabin floor.

ii. Sitting up is the best position.

iii. Press the motion sickness bag around the mouth with both hands

iv. Do not choke off the neck of the bag with your hand.

v. Hold the bad snuggly against your face until all vomiting or retching

ceases.

vi. Once vomiting/retching has ceased immediately seal the motion

sickness bag.

vii. Use available paper towels to immediately clean up any spills.

viii.Place the used motion sickness bag and paper towels into a Ziploc

bag.

ix. Make sure you have fresh motion sickness bags available.

x. Most people feel much better after getting sick.

xi. If you continue to be sick, stay along the cabin walls out of the way

of other flyers.

xii. Flight personnel may move sick individuals to the seats in back.

Medication1. Anti-Motion Sickness Medications:

a. Are effective in limiting motion sickness.

b. Work by decreasing your sensitivity to motion.

c. However, if the motion is severe enough, you can still experience

motion sickness.

d. The beneficial effect of the medication can be nullified if you do

not follow the recommendations outlined earlier.

e. The available medication may have some side effects:

i. Dry mouth

ii. Mild sleepiness/sedation

iii. Mild decreased concentration

iv. Changes/blurring of vision

Preventiona. Hard candies and water are available during the flight to help

with dry mouth.

b. The medication must be taken properly for it to work:

i. Must be taken exactly as directed by flight personnel.

ii. Must be taken at least one hour prior to takeoff to be effective.

iii. Must be taken under the direct supervision of the flight personnel.

c. Because some of the potential side effects might impair your

ability to safely drive a vehicle, you must designate someone

who will drive you around for the rest of the day after you take

the medication. You cannot receive the medication if you do

not have a designated driver.

After the Flight:a. General recommendations:

i. By the time most flyers disembark from the airplane after their flight, they are

feeling fine . If anything, they are hungry and thirsty.

ii. Occasionally, first time flyers can notice some dizziness or feeling of instability

after their flight. This could potentially interfere with their ability to drive or

operate heavy machinery. Because of this, it is recommended that on the day

of your flight, you do not drive, operate other machinery or engage inactivity

that requires a lot of coordination, especially if you feeling dizzy or unsteady.

iii. After your flight, make sure to drink plenty of fluids. Flying in the Zero-G

aircraft can deplete your body’s fluid stores.

iv. You should minimize alcohol intake after a flight. It can lead to more

dehydration and can negatively interact with the anti-motion sickness

medication. Drinking alcohol after flight can cause motion sickness symptoms

to return.

v. Avoid strenuous activity. Your body needs rest to adapt to the vigorous

sensory information it experienced during flight.

Post Flighta. If you are not feeling well after your flight:

i. Occasionally, some people continue to have symptoms of motion sickness

after returning from flight. Symptoms are virtually always gone after a good

night’s rest.

ii. If you are still feeling quite poorly after your flight, tell the flight personnel

before you leave the hangar.

iii. If you do continue to have motion sickness symptoms, the most important

thing is to rest and avoid any activity or motion.

iv. Rest quietly in a cool, dark environment.

v. If possible, drink plenty of clear liquids.

vi. Eat light food (crackers, bananas) only as tolerated.

vii. If, despite these measures, you are still feeling uncomfortable, further

medical advice regarding motion sickness is available. Contact Flight

Clinic (281) 483-7999. Tell the person who answers that you have just

flown on Zero-G aircraft and would like to speak to the Flight Surgeon. The

Flight Surgeon will evaluate your situation and determine what to do next. If

no answer, contact JSC Security at (281) 483-4658.

Detailed Research Activity Planning (Putting it all together): Exactly what are you going to do during parabolic flight? What

steps must you compete during your experiment? To understand exactly what each step of your experiment entails, think about the following points. To help yourself keep things straight, write things down.

a. What physical motions and activities are needed for a given step?

b. Think about exactly when each step must be performed. Will the

activity be performed in microgravity, during the high-G pull-out or

both? Determining this will help you determine where to put the

equipment so that it is easily available during the appropriate period

without having to move around.

c. Does the task require one hand, two hands, or no hands? Makes sure

you are adequately restrained to get the job done without floating

away.

d. What equipment do you need to perform the task? Make sure the

equipment is positioned so that you don’t have to move around to get

to it.

e. Do you think you’ll be doing the step during the high-G pull-out? Practice performing

the step while lying down or sitting down and keeping your head still. Plan on using a

stiff notepad so you can write while lying down and holding notepad over your head.

f. How long do you think it will take to perform the task? Remember that it usually will

take you a lot longer than you think it will. Practicing on the ground under normal

gravity will show you how long it typically takes. A rough estimate is to double the

time to see how long it will take you during parabolic flight - practice it on the ground

first!

g. What do you do if you or one of your experiment partners gets motion sickness and

can’t complete their steps? Can somebody else finish their steps for them? Can you?

h. Carefully look at each step of your activities and compare them to the

recommendations given earlier. If you determine that an activity might cause you to

break some of recommendations given above, think about how to adjust that activity

or place your equipment to minimize a problem with the activity. Doing this before

flight can help you eliminate physical activities positions that are too provocative.

Detailed Research Activity Planning (Putting it all together): (Con’t)

Conclusion:Although motion sickness can occur during parabolic flight,

there are steps that you can take to prevent it. Knowing what to do (and not to do) is the key to motion

sickness prevention. Taking a little time to plan ahead will go a long way to help

you finish your experiment, experience microgravity and have a great time!

Following these step-by-step guidelines is the best way to avoid motions sickness. These guidelines also discuss how to manage motion sickness symptoms and limit their impact on your flight experience.

Don’t forget that the RGO aircraft flight personnel are also available for advice or assistance. They have put forth a lot of care and effort to make sure your parabolic flight experience is enjoyable and rewarding.

Plan ahead, don’t worry and have a Great Time!

QUIZDuring the high–g pull-out you should ____

a) Move aroundb) Hold your head and neck stillc) Make rapid head movements

The night before your flight you should____a) Drink plenty of fluids and restb) Stay dehydratedc) Drink only clear alcoholic beverages

The morning of your flight it is best to eat ___a) Nothingb) Greasy foodc) Light meal that agrees with you

During the micro-g phase of flight you should__a) Kick and flailb) Move slowly and in control, holding on to structurec) Twist you head and neck quickly

If you feel ill it is best to______a) Stop what you are doingb) Look out the windowc) Lay face down

QUIZ (Con’t) If you are about to get sick you should____

a) Sit up, signal NASA TDs, hold bag firmly around the mouth with both hands.b) Let go and float freec) Close your eyes and squeeze the bag tightly

If you begin to get sick you must____a) Get everything in the bagb) Go the lavatoryc) Go to the front

Effects of parabolic flight may last ____a) Well into the evening in some casesb) A lifetimec) 12 minutes

Avoid ____ immediately after flighta) Drinking alcohol, strenuous activity, driving if on medsb) Walking, or dancingc) The ‘noid

Medications are effective and may affect you for ____a) Eternityb) A weekc) Several hours

Signature PageI ______________, have read and understood the causes and potential effects of parabolic flight, and the associated physiological and spatial disorientation issues.DATE OF BRIEFING: _____________

_____________________________NAME