Mid-Altitude Training

1
Mid-Altitude Training
2
Power Available and Rate of Climb

• Power output of non-turbocharged engines
  decreases 2.5 per 1000 climbed.
• ROC depends on excess power available, so it also
  drops with altitude.

• Do not attempt high ROCs above 8,000
• Be particularly careful if AP is engaged in VS
  mode
• VS attainable at low altitude may be impossible
  as altitude is gained
• AP will attempt to maintain selected VS and will
  fly aircraft into a stall.
• Recommend no more than 500 FPM selected above
  8,000

3
Relationship between IAS and TAS

• The IAS attainable by an airplane is mostly a
  function of available power, which decreases with
  altitude.
• At 17,500 an SR-22 may cruise at 160 KTAS, with
  an IAS of only 120.
• The way an aircraft handles and feels is mostly
  related to IAS, not TAS.
• A given control deflection will be less
  effective airplane may feel more mushy.
• Autopilot will be less precise in control of
  aircraft

4
Icing

• Even in summer icing is a concern above 10,000
• Standard temperature lapse rate is 2C/ 1000
• Takeoff from SL _at_ 20C, temperature at 10,000 is
  approaching zero
• Lifting present in summer cumulous can cause
  formation of Supercooled Large Droplets (SLD)-
  responsible for most severe icing possible.
• At high altitudes
• Less power is available to counteract drag of ice
• Margin between Stall IAS and Cruise IAS is
  smaller- increases chance of ice-induced stall
• Do not fly into clouds if OAT is at or below 0C,
  regardless of season.

5
Atmosphere

• Air is 78 Nitrogen, 21 Oxygen, 1 Other
• Ratio stays the same as altitude increases, but
  density decreases
• Atmosphere is half as dense at 18,000 as at sea
  level.

6
Hypoxia

• A lack of sufficient oxygen in cells and tissue
  caused by
• Inadequate supply of oxygen
• Inadequate transportation of oxygen
• Inability of the body tissues to use oxygen

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Types of Hypoxia

• Hypoxic
• Caused by insufficient oxygen in inhaled air
• Histoxic
• Inability of cells to use oxygen
• Caused by alcohol or drugs
• Hypemic (Anemic)
• Reduced oxygen carrying capability of blood
• Carbon Monoxide/ Tobacco Smoke reduced ability of
  blood to transport oxygen
• Smokers apparent altitude at SL is 7,000
• Stagnant
• Reduced circulation of blood to tissues
• Coronary Artery Disease
• Excessive G-Forces

8
Hypoxia- Potential Symptoms

• Impairment of
• Judgment
• Memory
• Alertness
• Coordination
• Ability to make calculations
• Headache
• Drowsiness or fatigue
• Dizziness
• Increased breathing rate
• Sweating
• Euphoria or belligerence
• Loss of peripheral vision
• A blue coloration of the fingernails and lips
• Tingling or warm sensations

9
Factors Exacerbating Hypoxia

• Inhaling carbon monoxide
• Cigarettes
• Exhaust fumes
• Anemia
• Genetic
• Pregnancy
• Medications/ Drugs
• Alcohol
• Antihistamines
• Tranquilizers
• Sedatives
• Analgesics (pain-killers)
• Extreme heat and cold
• Fever
• Anxiety

10
Decompression Sickness

• Two Forms
• Trapped Gas
• Expanding or contracting gas in body cavities
  during altitude changes can result in abdominal
  pain, toothache, or pain in ears and sinuses if
  the person is unable to equalize the pressure
  changes.
• Above 25,000 distention can produce particularly
  severe gastrointestinal pain.
• Evolved Gas
• Air we breath is 78 Nitrogen.
• Most nitrogen is exhaled from the lungs some is
  absorbed by the body. Absorbed nitrogen does not
  normally present problems because it is carried
  in a liquid state.
• If ambient pressure lowers drastically, absorbed
  nitrogen changes from a liquid to a gas in the
  form of bubbles which can have adverse effects on
  some body tissues.
• Fatty tissue contains more nitrogen than other
  tissue thus making overweight people more
  susceptible to evolved gas decompression
  sicknesses.

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Decompression Sickness

• Types of evolved gas decompression sickness
• The bends (Caisson disease)
• Characterized by pain in and around the joints.
• Pain gradually becomes more severe, can become
  temporarily incapacitating, can result in
  collapse.
• The chokes
• Chest pains and burning sensations
• A desire to cough
• Cyanosis
• Sensation of suffocation
• Progressively shallower breathing
• Ultimately, collapse and unconsciousness.
• Paresthesia (Pins and Needles)
• Tingling and/ or itching
• A red rash
• Cold and warm sensations
• Shock can result from decompression sicknesses as
  a form of body protest to disrupted circulation,
  can cause
• Nausea
• Fainting or dizziness
• Sweating

12
SCUBA

• Diving will compound decompression sickness due
  to compressed air breathed during dive.
• After diving, flying to 8,000 exposes a person
  to the same effects as a non-diver flying
  unpressurized at 40,000.
• FAA recommendation and ASE policy on waiting
  periods is
• After decompression stop dive, at least 24 hours.
• After non-decompression stop dive
• If flying above 8000, at least 24 hours.
• If flying at or below 8000, at least 12 hours.

13
Vision at Altitude

• Reversal of light distribution at high altitudes
  (bright clouds below the airplane and darker,
  blue sky above) can cause a glare inside the
  cockpit.
• Glare effects and deteriorated vision are
  enhanced at night when the body becomes more
  susceptible to hypoxia and can occur at altitudes
  as low as 5,000 feet.
• Empty visual field caused by cloudless, blue
  skies during the day can cause inaccuracies when
  judging the speed, size, and distance of other
  aircraft.
• Sun's ultraviolet rays at high altitudes are more
  intense- sunglasses are recommended.

14
Negative Effects of Oxygen

• Prolonged use can be harmful to health, with
  symptoms including
• Bronchial cough
• Fever
• Vomiting
• Nervousness
• Irregular heart beat
• Lowered energy
• Symptoms appeared on the second day of breathing
  90 percent oxygen during controlled experiments.
  It is unlikely that oxygen would be used long
  enough to produce the most severe of these
  symptoms in any aviation incidence.
• Prolonged flights at high altitudes using a high
  concentration of oxygen can produce some symptoms
  of oxygen poisoning such as infection or
  bronchial irritation.
• Sudden supply of pure oxygen following a
  decompression can often aggravate the symptoms of
  hypoxia.
• Oxygen should be taken gradually, particularly
  when the body is already suffering from lack of
  oxygen, to build up the supply in small doses.
• If symptoms of oxygen poisoning develop, high
  concentrations of oxygen should be avoided until
  the symptoms completely disappear.

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Regulations re Oxygen Use
FARs

• Flight Crew must use oxygen at Pressure
  Altitudes
• Above 14,000 for any time
• 12,501- 14,000 for more than 30 min
• All passengers must be provided with oxygen above
  15,000 PA
• Flight Crew must use oxygen at PA-
• Above 12,000 for any time
• 10,001-12,000 for more than 30 min

ASE PPs
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Oxygen System Components
Cannula/ Mask
Only in Emergency
Regulator
Oxygen Tank
Preferred Equipment
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Oxygen Bottle
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PreciseFlow Demand Conserver

• Regulates 02 to mask so that 02 only flows when
  wearer is breathing
• Useable with dual-lumen cannula or mask
• With cannula
• Connect Delivery and Sensing outlets to
  cannula
• Set mode selector to CONSERVE
• With mask
• Connect Delivery outlet to mask
• Set mode selector to CONSTANT
• Set cruise altitude against triangle with
  altitude selector
• Flow indicator built into tubing from 02 tank
• Shows on/ off only, not rate of flow

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A-3 Flow Meter

• Hold vertically, adjust flow until floating ball
  (flow indicator) is at level of cruise alt on alt
  scale
• Check every 15 min with pulse oximeter check
• Normally use only with Oxymizer cannula
• In case of nasal blockage/ equipment malfunction,
  may use with mask
• With mask, adjust flow to maximum (full open),
  regardless of altitude

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Dual- Lumen Cannula

• Use only with PreciseFlow regulator
• Worn in nose
• Only effective when breathing nasally
• Talking, mouth breathing reduce effectiveness and
  lower Sp02
• Limitations
• Face mask must be accessible for anyone required
  to use/ have available O2, in case nasal blockage
  develops
• May not be used above 18,000
• Regular smokers may not get enough oxygen with
  cannulas
• Add 7,000 to cruise altitude when adjusting flow
• Not recommended above 11,000

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Oxymizer Cannula

• Use only with A-3 flow meter
• Bladder holds O2 until breathed in allows for
  lower flow rate than mask
• Same concerns and limitations as dual-lumen
  cannula

22
Face Mask

• Normally use only with PreciseFlow regulator
• May use with A-3 if cannula malfunctions or is
  ineffective
• Use
• If nasal blockage experienced
• Smoker who needs high flow rate
• Not guaranteed to work with beard
• Higher the altitude, worse the effectiveness with
  beard
• Need to use hand mike when wearing
• Push boom mike up

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Oxygen System- Preflight Inspection

• Visual inspection of
• Masks, cannulas, and tubing for tears, cracks, or
  deterioration
• Regulator for valve and selector condition and
  positions
• Oxygen quantity
• Don mask or cannula and perform functional check
  of flow, flow indicators, and connections.
• Verify that all components and valves are shut
  off.

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Oxygen System- General Tips

• Unless aircraft is full, always have one more
  regulator and mask/ cannula set up and connected
  than required
• Don cannula or mask before TO if planning a climb
  to gt10,000, easier than donning in-flight
• Immediately prior to takeoff
• Turn on O2 at bottle
• Turn regulator to high flow level and verify flow
• Turn off regulator until O2 needed
• Petroleum products, such as lipstick, chapstick,
  and hair oil may spontaneously combust in the
  presence of 100 O2
• Do not use, and ensure that passengers do not
  use, if using O2
• No occupants may remain in the aircraft if O2
  bottle is refilled while in aircraft
• Anecdotal evidence suggests women
• May need O2 earlier than men
• May need to set flow to higher than cruise alt.

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Pulse Oximeter

• Worn with fingernail against screen side, turns
  on automatically when worn.
• Artificial fingernails may impede reading
• Nail polish said to be OK
• Uses red and infrared light to measure pulse rate
  and level of oxygen saturation in blood (SpO2).
• ASE Policy is to check SpO2 every 15 minutes when
  using oxygen, or with any concern re hypoxia.
• Maintain SpO2 above 90
• If necessary adjust O2 flow to higher altitude
  than cruise altitude.

(Green, Yellow, or Red)
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Pulse Oximeter- Limitations

• Does not detect nor account for effect of carbon
  monoxide in blood
• Doesnt warn about CO poisoning
• Smokers SpO2 may look fine even when hypoxic
• Dependent upon presence of a good pulse may not
  get good reading with
• Very low blood pressure
• Impaired blood flow to the fingers
• Cold temperature causing constriction of the
  blood vessels in the extremities
• Drug use which causes
• Vasoconstriction or vasodilation (e.g.,
  nitroglycerine), or
• Change in blood color (e.g., sulfonamides).

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Oxygen System Failure

• If no or low flow is suspected, check
• Connections
• Tank to regulator (likely to pop off)
• Regulator to mask
• Kinks or twists in lines
• Master on/ off valve
• Flow adjustment on regulator
• Try another mask/ cannula and regulator hook-up
• If unable to resolve quickly, descend to 10,000
  or lower

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Emergency Descent

• 1. Power Lever- IDLE
• 2. Mixture- AS REQUIRED
• Caution
• If significant turbulence is expected do not
  descend at indicated airspeeds greater than VNO
  (178 KIAS)
• 3. Airspeed- VNE (201 KIAS)