Errors and Innovation
Posted: January 25, 2015
Many great ideas and innovations come about as a result of error or failure. Aviation is a field where error sometimes results in lethal consequence. Soaring flight is a type of aviation with its own unique challenges and safety concerns. Soaring is a recreational (and sometimes competitive sport) in which pilots fly unpowered aircraft known as sailplanes or gliders. Sailplanes are typically towed aloft by a tow plane, and then released at an altitude of 1000′ to 2000′ feet. Sailplane pilots utilize lift (regions of rising air) to stay aloft, and often can fly hundreds of miles for many hours.
Sailplanes are designed to be aerodynamic, with narrow fuselages and long thing wings. One of the results of these design constraints is that pilots are typically seated in a very reclined position.Two risks in soaring flight are the risk of mid-air collision due to multiple gliders in close proximity in a region of lift. Another risk is structural failure due to flying in extremely turbulent air. In the event of an emergency from one of the above risks being realized, a sailplane pilot may need to rapidly bail out of the sailplane and parachute to safety. However, a fast exit from a sailplane may be impeded by a number of factors including:
- Low reclined seating position
- Narrow cockpit designs make lifting the upper body with arms only very difficult
- Poor physical condition or injury to the pilot after a collision
- High g forces such as those found in a spiral dive after a midair collision.
Consider that in a spiral dive following a midair collision, at a typical 2G acceleration a 120 pound pilot would be trying to lift 240 pounds out of the seat with just their upper arms in a very short time period.
DG Flugzeugbau, manufacturers of the DG series of sailplanes introduced an innovative safety system to address these concerns after a high profile fatal midair collision of involving a DG-800A sailplane collided with another glider. Although the DG-800 pilot was conscious following the collision, he was not able to bail out of his sailplane before impact with the ground.
The NOAH safety system is now available for DG and LS series sailplanes. In this system, an aircushion is built into the seat. It is activated using a single lever. Once activated, the seat belt is released, and the air cushion inflates to the height of the cockpit fuselage, allowing the pilot to easily just roll over the side of the aircraft to exit the cockpit (as seen in the photo below).
The forces that drove this innovation were two fold. The idea behind the NOAH system was actually proposed many years before it was put into production by DG. It did not receive widespread support among the soaring community until after several high profile collisions in which pilots were known to have survived the collision but were unable to escape the aircraft. Fear of litigation might have been one motivation in the development of this system, community outrage might have been another. I believe DG had nothing more than the honorable goal of making soaring safer as their motivation which has been demonstrated by their willingness to help pilots retrofit their system into sailplanes manufactured by other companies.
Today the NOAH system a standard offering for DG sailplanes. In 2011, a proposal was made at the Soaring Society of American annual convention to require NOAH systems as all SSA sanctioned soaring events in addition to the already mandated parachute requirement. This proposal has yet to be enacted.
Johnson, S. (2010). Where Good Ideas Come From: The Natural History of Innovation.
DG Flugzeugbau. Emergency Exit Assist System: NOAH. Retrieved from
http://www.dg-flugzeugbau.de/noah-e.html on January 19th, 2015.