II. History of High Altitude Glider Flying and its Medical Aspects
Wave Flying has become increasingly important in recent times, as equipment and knowledge have improved over the last ten to fifteen years. Long Distance Wave Flights in the European Alps now happen regularly. In New Zealand and France during the last world championships the competitors had to prepare for wave flights at altitudes of up to 23 000 ft / 7000 m.
- At altitudes of more than 20 000 ft / 6000 m, flying is lethal without oxygen. Decompression Sickness (DCS) with Types I and II (minor symptoms up to CNS and cardiovascular collapse) can readily occur and may destroy the health of a pilot.
- Adequate oxygen equipment and hypobaric chamber-training should be mandatory for this type of rigorous and demanding glider flying. It is imperative for flight safety. In the USA altitude records of about 50 000 ft / 15000 m and recent speed records (Jim Payne) were all done with aid of the wave! In the USA, Poland, and the former GDR, hypobaric chamber training along with hyperbaric chamber facilities were widely supported by the authorities, even demanded in some places, prior to wave flying.
- For a long time in Germany there has been a general lack of knowledge about oxygen needs when flying above 10 000 ft / 3000 m, with obvious detrimental influences on flight safety. This was the case for many years and no action was taken to improve this situation, even though expert opinion and knowledge in this field was available. One famous "Alpensegelflieger", Jochen von Kalkreuth, died at high altitude several years ago of hypoxia in his glider, apparently due to confusion about high altitude limits. The common situation was that expensive oxygen equipment was rarely bought or used.
- With intensive support by the German Armed Forces, namely by Rainer Wienzek from Bueckeburg, the Military Flying Club and the knowledge and training by the Institute of Aviation Medicine, this situation in Germany has improved during the last ten years. It has focused on the following main subjects: 1. OXYGEN DEFICIENCY AT ALTITUDE, 2. DECOMPRESSION SICKNESS (DCS), 3. OXYGEN SYSTEMS.
- Inexpensive, newly developed, Oxygen Demand Systems, like "EDS" from Mountain High/USA and "FLOWTIMER" from Spiegelberg in Hamburg have helped to resolve the problems of the limited stores of oxygen that can be carried aboard a glider. Now it is possible to fly for more than 11 hours with a 5 ltr bottle up to 18 000 ft / 5500 m.
- At altitude new "PULSE OXYMETRY" devices can measure the amount of oxygen available in the pilot’s body, more commonly known as the oxygen saturation of hemoglobin, using a sensor clip on the finger. This measurement shows the pilot that he is either in a "safe" range or that he is becoming hypoxic.