private pilot ground school Articles | Index    

Hypoxia
2010-03-18

Hypoxia

An adult will breath in 3,000 gallons (by volume) of air per day. This includes 600 (20% of total) gallons of oxygen. Your blood system has 25+ trillion (12 zeros) red blood cells (hemoglobin). Each one is capable of loading up four oxygen molecules for distribution throughout the body. when returning to the lungs for a refill they unload CO2 first.

Hypoxia is oxygen starvation. Lack of oxygen impairs the whole body but most importantly the brain. The first part of the body to show significant effect from oxygen deficiency is the retina of the eye. Every individual is affected but in different ways and to different degrees. The danger in hypoxia is that it occurs insidiously below the conscious threshold. Hypoxia makes you happy and such happiness in the cockpit is very dangerous. The best warning indicator for hypoxia is the altimeter. You will quickly recover by descent to a lower altitude.

Since hypoxia is due to reduced barometric pressure, low-grade hypoxia begins on takeoff. The percentage of oxygen is same but less is reaching the blood stream. Any stress or increase in activity requires more oxygen, up to 8 times more. Pilot performance deterioration begins at takeoff, as well. Slowed response times and inability to deal with complexities due to hypoxia compromise safety. Noticeable oxygen deficiency effects begins at 4000’ safety margins are beginning to erode. Hypoxic symptoms of difficulty breathing or headache may not be obvious or may not occur at all even though there are the foregoing changes in mental status.

I have seen complete personality changes occur after a couple of hours around 12,000’. Symptoms such as headache, drowsiness, dizziness, euphoria, tingling, perspiration, or belligerence are typical. Tunnel vision and blue fingernails occurs with times as little as 15 minutes above 15,000’. At 16,000’ disorientation, lapses of judgment, loss of impulse control, risk-taking behavior, decreased problem solving abilities, impaired memory, mood disturbances, and lowered coordination are common. Unconsciousness occurs in 10 minutes at 20,000’.

All effects are made worse and happen at lower altitudes with fatigue, age, smoking, health habits, and drinking. Oxygen recommended above 10,000 day and 5,000 night. If oxygen is being used, the pilot must be knowledgeable about the operation of the system and be able to recognize his and the system’s warnings of oxygen deficiency. FARs require oxygen if ½ hour above 12,500’, crew above 14,000’, everybody above 15,000’.

Comment

 
 External Links
 Recent articles
About Students
ol li A student won #39;t learn from those they distrust BR li A student won #39;t improve unless told what...

Airline Pilots
The second most frequent cause of death among airline pilots prior to age 60 is a general aviation accident P ...

Flight Contradictions
ul li The rudder is not used to turn the plane Rather it keeps the nose straight BR...

First Flight Preparations
P 1 Schedule aircraft instructor BR 2 Aircraft keys BR 3 Read Owner #39;s Manual BR 4 ...

Fuel Accidents
ul li The number one cause of engine failure is lack of fuel BR li 10 of General Aviation accidents are caused...

Standard Rate Turns
P All banks under the hood are at standard rate Standard rate turns requires two minutes to make a 360 degree circle One minute for a...

Applicant Summary
You must have an application for a rating form FAA Form 8710 1 a waiver form as required a medical certificate and radio license for foreign...

Landings on Final
Over the fence Vref U U 5 knots or 1 2 Vso No exact POH figures BR B Soft field Approach...

VFR to IFR Options
P What to do If you #39;re on top do the four C #39;s Climb communicate confess comply If fuel and weather...

Time For First Solo
This method to safely soloing a student puts the burden on the student It is not the way I do it but it is worth considering ...

The Last Thing You Learn
P If you make a good landing the yoke should be positioned for taxiing When you turn off the runway the correct positioning of the yoke will...

Major CFI Applicant Problem Areas
P middot; Not fitting lesson to student level BR middot; Too much talking without check on comprehension BR middot; Avoiding unknown an...

Mad As Hell And Taking It
P In flying we react in an emergency as we first learned to react When we show anger we react as we first learned to react Just...

Postflight Debriefing
The postflight debriefing begins as a self evaluation by both student and instructor as to why certain operations were less than successful or why...

Pilot Error 50 Years Ago
P In December of 1947 an Air Force study released the following analysis of pilot errors that precipitate accidents There is no reason to think things have...

Emergency Landing
Best glide U U 10 knots ...

Practice Illusions
P B Autokinesis B BR On a dark night fly toward a single light Student is to stare only at the light...

Spin Awareness (Discussion)
Flight situations where spins may occur BR Recognize a spin and apply recovery technique BR Techniques specific to aircraft BR power off and flaps up...

It's About Time
A sailing ship #39;s speed over a nautical a mile was historically measured by means of a knotted knots rope tied to a log...

Advice to instructors
P Go down to lost and found and get your memory every time you have a senior moment P P As a...

Planned Instruction
The military is a leading exponent of programmed instruction Under such a program every thing in the future is based upon the building blocks...

Fitting The Hood
P The hood should be fitted prior to engine start Note that the attitude indicator has both a wings level and a level index mark at its...

A History of Running Lights
I have developed a possible sequence for the development of red and green running lights on ships and aircraft I would like to make the following case ...

Fatigue and Flying
P Acute fatigue occurs when a long period passes with a lack of sleep Chronic fatigue occurs when several acute fatigue periods occur without adequate recovery time...

WD-40 and Cleaning
P The use of WD 40 is not recommended on aircraft It is not recommended because only a light lubricant is left after the solvents evaporate ...

The Instructor
I can teach you to fly in about five minutes but it will take the rest of your life to get it right It is not just...

Lost Procedures
Maintains original heading BR Identifies available landmarks BR Uses Navaids and contacts ATC for assistance BR Considers precautionary landing as an option ...

Crash Survival
#1 survival item is to let a responsible person know where you are going your route and ETA Insurance is to make contact after arrival ...

Soft-field Takeoff
P Introduction BR The situation is a takeoff area of unlimited length but having a soft surface the nature of which would prevent acceleration ...

Special Use Airspace (SUA)
P Not on charts but often mentioned by VOR Tower broadcasts Locally by Livermore ATIS to warn of National Guard firing range near Danville San Ramon border...

It's About Judgement
P In flying there are as many ways to gain skill and experience as there are pilots Time alone is a very poor criteria Once pilot...

Temporary Flight Restrictions (TFR)
P Broadcast by ATC to warn air traffic to remain clear of areas such as open air affairs forest fires space launches crime scenes ...

The Competence of Incompetence
With the advent of a new study as to what constitutes competence there is a new fear by the self assured that they may be among ...

Eights
P Eights combine the skills acquired from doing left and right turns about a point and S turns First find a with one leg giving ...

Airworthiness Directive
P B AD Compliance Record B P P Aircraft No: Make: Serial Number P ...

About Questions
P A friend was hauling a body from a remote location in Canada Only a caretaker was around the strip After considering the trees that lined...

Engine Logs
P B Overhaul B P P Does not change prior history Time is added as quot;since overhaul quot;...

The PTS
Everything about the Practical Test is a given If you have studied the PTS you know what is going to happen You may not know when or just how...

1995 Statistics
Most flying decisions are easy if the decision is based upon safety Being safe does not mean without risk Engine operations are safe...

IFR Rated Pilot
ul li 1 accident in 4 459 hours in IFR conditions BR li 1 accident in 61 900 hours in...

Private Pilot Endorsements
An instructorÝs endorsement indicates that he feels you have been instructed in and are competent to perform a given maneuver At that time Your logbook is a legal document...

Downwind Takeoff
P demonstration BR At controlled airports the non assertive pilot just goes where he is told to go There are occasions where for convenience...

Trim Use
P Correct use of the trim requires that control pressures be applied to hold the desired flight attitude Then the trim is adjusted to relieve present control...

Cold Weather
P Hot or cold temperatures affect the quality of the preflight In the winter as your body cools you tend to mentally and physically slow down...

Shirt Tails
There has been a long tradition in aviation related to cutting off the shirt tails of newly soloed student pilots One story has it that the practice ...

A Need to communicate
P What is the only question an instructor can never answer It is the unasked question Many concerns are unspoken The unspoken fear of every...

On Checklists
ol li Flying an airplane requires that a series of relatively complex procedures A checklist is most viable if a long series ...

Teaching Precepts
P Docendo Discimus We learn by teaching When by yourself you are the instructor BR BR ...

Age as a Factor In Flying
P The average General Aviation pilot was 39 years of age in 1990 Pilots over 60 have 2 1 times more accidents than pilots in their 50...

Private Pilot Requirements
At least 17 read write and speak English 3rd class medical written test oral test flight test 61 103 BR Private...

 Related Links
 
©2010 4VFR.COM, All Rights Reserved Powered by 4vfr.com