Upcoming Jumps

Halo Briefing

Oxygen System
Jump Procedure
Physiology
Blood Oxygen Saturation
Preventive Measures
Time of Useful Consciousness

DISCLAIMER: THE AUTHOR MAKES NO WARRANTIES OR REPRESENTATIONS AND ASSUMES NO LIABILITY CONCERNING THE VALIDITY OF ANY ADVICE, OPINION, OR RECOMMENDATION EXPRESSED IN THIS MATERIAL. ALL INDIVIDUALS RELYING UPON THIS MATERIAL, DO SO AT THEIR OWN RISK.

ALTITUDE:
Normal variations in barometric pressure can change the exit altitude plus or minus 300' above ground level. Jumpers should set their altimeters to ZERO at takeoff and should not adjust their altimeters during the flight to Exit Altitude. At high altitudes it is not uncommon to see differences as large as plus or minus 500' ft between typical skydiving altimeters. Jumpers MUST NOT set their altimeters from the aircraft altimeter. Skydiving altimeters will usually stop recording at some point on the climb - needles will stop moving or digital displays will go blank. They usually will start working on the way back down. FREE FALL time from 18,000 is approximately 1 minute and twenty seconds, 22,000 - 1'40" and 30,000 - 2 minutes. These again are approximates and can vary plus or minus 10 seconds.

Your Ears:
Another aspect of High Altitude jumping is the fact that the decreased atmospheric pressure will require that each jumper continuously equalize (EQ) his or her ear pressure during the accent and in freefall. Although rare, failure to EQ your ears can result in a very painful EQing after opening and or a ruptured ear drum. Jumpers can equalize by simulating a chewing motion, yawning motion, or by pinching the nose and with the mouth closed attempting to blow air from the mouth. This will be practiced during your training. (Valsalva techniques)

OXYGEN SYSTEM:
Six-man portable Pre-Breathing 02 console, manufactured by American Safety Flight Systems, Inc. This console will provide 100% oxygen to six jumpers for one hour. MBU 12/P or MBU 5/p demand oxygen mask, CRU 60 O2 manifold and or Airox VIII demand regulator, twin 22 bailout bottles (12-15 minutes of air in FREE FALL) or twin 53 bailout bottles (45 minutes). The masks have an FAA TSO and are certified 40,000 feet. These mask are very expensive, so please take care that they are not damaged.

JUMP PROCEDURE:

Prior to your jump you will be required to attend a short class which will familiarize you with your issued equipment and safety procedures for high altitude jumps. After the class you will be fitted with an oxygen mask and helmet, this may take a few minutes so please be patient. Your bailout bottle will be attached to your rig or if you are jumping HALO rigs provided by the instructor they are already attached. Upon being fitted with all your equipment you will receive a Jump Master safety check and then directed to the console and assigned to a specific port or 02 hose. You will also be paired off with another jumper for the flight. Each jumper will monitor their "buddy" for signs of hypoxia and or hyperventilation. The O2 Monitor/safety officer will check each jumper as well as we climb to exit altitude.  Jumps of 18,000 to 22,000 will not need pre-breathing and we will begin breathing 100% oxygen at 10,000 feet. Jumps over 22,000 will require a 30 - 45 minute pre-breathing period to flush the nitrogen from our blood stream. Jumpers will begin breathing 100% 02 (ABO) in the plane for 30 minutes and after take off continue breathing 100% 02 (ABO) all the way to exit altitude for a total of 50-55 minutes. You will receive supervision and instruction during jumps over 22,000 feet. As the flight ascends to exit altitude, the Jump Master will check your blood 02 level and record both your heart rate and 02 saturation. As the masks are demand type, you must make sure you have a snug fit and when you take your first breath you will notice a cold or cooler air entering the mask. This cooler air is from the console and will confirm air flow has started. it will be very obvious that air is flowing each time you inhale. Do not remove the mask from your face to exhale. Important: If while inhaling, you remove your mask from your face, the oxygen will keep flowing through the mask until you place the mask back on your face and exhale. This is normal but it will waste a tremendous amount of oxygen. NOTE: If you are pre-breathing for a higher jump and you remove your mask prior to exit altitude, you will negate your nitrogen purge and could suffer symptoms of the Bends. Just one breath of regular air will return your blood levels close to normal and you may need to abort your jump for safety reasons. Again the Jump Master and 02 Monitor will be checking you as we go to altitude.

About 2 minutes prior to exit, the pilot will give the two minute warning. (Hand Signal) At this time bring your attention to the Jump Master. The Jump Master will point to the jumpers as a group and then give the hand signal to "open" or "turn on" your bailout bottle and disconnect. Remember, turn on your bottle, take a deep breath, hold it, disconnect from the console, and then inhale, breathing normally and checking your flow meter or Blinker. Place the hoses in a pile behind the console on the far side of the plane. CRU 60 users will connect their "Mushroom" to ease in exhaling. This entire procedure will take less than 30 seconds and is factored into your exit, so do not rush, but perform the procedure in a timely manner. Please confirm that you are not entangled in the hoses, place yourself in "Standby" and prepare to exit on command. the Jump Master will open the door and perform a visual "Spot" confirmation. The Jump Master will point at you and then point at the door, you will then exit the plane. If the plane has standby and exit lights, the Jump Master may direct your attention to the lights, whereupon you will exit at the lighting of the "Green" light. The standard exit is a front to rear trailing exit.  This exit will be practiced on the ground.  At no time will you grab the inside edges of the door, as you approach the door and feel you have to grasp the edge of the door, place your hands outside the door and grasp at the piont the outer skin joins the door bulkheads.  This " Grasp" will be demonstrated in class.

NOTE: A "No Show Exit" is recommended at higher altitudes due to the time and exertion that is expended in an oxygen poor environment putting out floaters. You will be required to tell the pilot and Jump Master the type of exit you will perform.

PHYSIOLOGY:
Please read this section completely. The time of useful consciousness without supplemental oxygen at 23,000 is approximately 4 minutes. The jumpers are exposed to an environment without sufficient oxygen for 1 minute and 54 seconds. This is based on the jumpers removing their mask and exiting the aircraft within 1 minute plus a free fall time of 54 seconds to 15,000 feet, where the time of useful consciousness is considered indefinite. This leaves a buffer of two minutes. NOTE: The symptoms of hypoxia and hyperventilation are identical except that you do not turn BLUE with hyperventilation. Sit still, breath normally and relax. If you are turning red, you are most likely Hyperventilating--Slow your breathing and relax. Counting at the end of each breath will help you focus on your controlled breathing exercise.

PHYSIOLOGY OF HYPOXIA:
Cause: Deficiency in the amount of oxygen that reaches the body's tissue. (e.g. exposure to altitude with progressively insufficient oxygen at higher cabin pressure altitudes).

Effect: The central nervous system, brain and other organs cannot function properly.

Contributing Factors: Smoking, alcohol, drugs (including antihistamines, antihistaitanes, tranquilizers, sedatives, and analgesics), anemia, carbon monoxide, fatigue and anxiety.

Manifestation: It is impossible to predict when or where hypoxia will occur during a given flight or how it will manifest itself, particularly if it occurs gradually.

Symptoms:

1. Increased sense of well-being (referred to as Euphoria) or belligerence.
   
2. Rapid breathing.
   
3. Slow reactions.
   
4. Impaired thinking ability.
   
5. Unusual fatigue.
   
6. Dull headache.
   
7. Warm or tingling sensation.
   
8. Sweating.
   
9. Loss or reduced vision.
   
10. Blue discoloration of the fingernails and lips.

NOTE: The symptoms are slow but progressive, insidious in onset and marked at altitudes above 10,000 feet.

ALTITUDE AND PERFORMANCE: Performance can seriously deteriorate within 15 minutes at 15,000 feet. Night vision can be impaired starting as low as 5,000 feet. Heavy smokers may experience early symptoms of hypoxia at lower altitudes.

ALTITUDE and BLOOD-OXYGEN SATURATION:
Sea level - about 95 - 98%

10,000 feet - about 90%
You could begin to experience some of the symptoms of blood oxygen starvation.

14,000 feet - about 84%
Thought, memory and judgment processes are greatly impaired. Peripheral vision may be affected and hands could begin to shake.

16,000 feet - about 77%
You may not be capable of controlling the aircraft and could even lose consciousness.

18,000 feet - Loss of consciousness could occur in 15 to 30 minutes.

Above 18,000 feet - Effects of hypoxia are described in terms of useful consciousness, which ranges from 10 minutes at 20,000 feet to 15 seconds at 40,000 feet. See chart below.

PREVENTIVE MEASURES:

1. Refrain from alcohol and do not smoke prior to flight.
   
2. Use only medications prescribed by a flight surgeon or aviation medical examiner.
   
3. Do not fly above 10,000 feet w/o supplemental oxygen on board.

SUPPLEMENTAL OXYGEN: FAR 91.211 requires that:

1. Pilots of un-pressurized aircraft use supplemental oxygen when flying higher than 12,500 feet MSL for 30 minutes or more and at all times above 14,000 feet MSL.
   
   
2. Every aircraft occupant be provided supplemental oxygen above 15,000 feet MSL.