United States of America
Stanley P. Desjardins (Stan) has contributed to helicopter safety by creating and developing crash survival technologies and incorporating those technologies in manufactured products. Stan started two companies that have conducted extensive research into crash survival technology and have advanced helicopter crash survivability in particular. His companies have conducted survival related research and development for several modes of transportation including not only helicopters but also fixed-wing aircraft, automobiles, passenger railcars, and spacecraft.
Stan was born in 1930 in the United States and grew up in Idaho. Prior to entering college, Stan’s US Army National Guard Battalion (Idaho) was activated and he eventually served as a Platoon Leader in the 3rd Infantry Division in Korea during that conflict. His rank when discharged was Master Sergeant. He used the GI Bill to attend the University of Idaho and earn a degree in mechanical engineering.
Upon graduation in 1958, Stan joined the Thiokol Chemical Corporation where he was first engaged in developing and qualifying the first stage of the solid-fueled Minuteman ICBM. Later he was given responsibility for all rocket nozzle design at the Wasatch Division. While at Thiokol, Desjardins continued his engineering education and received four patents on rocket motor technology.
Initial Helicopter Work
In 1968, Stan accepted a position with Dynamic Sciences (AvSER), a small Phoenix-based company devoted to transportation research. The company was working under contract from the US Army to study helicopter crash survivability. They were conducting full-scale drop tests of decommissioned aircraft and using the information gathered to create survivability technologies. Also working with Dynamic Sciences at that time were James W. (Doc) Turnbow and Harry S. Robertson, who also became leaders in crash safety technology. This research led to findings that post-crash fire and spinal injuries were the leading causes of fatal and serious injuries in helicopter crashes that could potentially be survivable. Furthermore, the research showed that the mitigation of these injuries was feasible. Harry Robertson went on to develop crashworthy fuel systems and Stan Desjardins to develop seats that absorbed crash energy by sliding downward with the stroking force controlled by energy absorbers. The energy absorber device limited the loads applied to the occupant’s spine. By reducing the compressive forces experienced by the seat occupant, spinal fractures are prevented. After determining that Dynamic Sciences was not interested in applying the technology and manufacturing the resulting products, Stan left and started Simula Inc. to not only continue developing energy absorption (EA) technology but also to supply the technology to the vertical lift fleet.
Stan initially formed Simula to design and produce EA seats, but he was also dedicated to continuing safety research and applying the results to the resulting hardware. The company’s first product was the crashworthy pilot seat for the UH-60A Sikorsky Blackhawk which used armored buckets manufactured by Norton Co, Worcester, Massachusetts. Eventually, the company opted to manufacture armored buckets in-house because of quality problems with the procured products and thus, moved into the armor business. Safe’s armor business became a major product line for the company when it expanded to include body armor as well as vehicle and ship deck armor. Simula went on to design and produced seats for other military aircraft including the SH-60B Seahawk, AH-64A Apache, SH-3 Sea King, CH-53 Sea Stallion, V-22 Osprey tilt-rotor, UH-1Y Venom, and AH-1Z Viper. Simula also produced seats for several foreign military aircraft, including the Westland/Agusta EH101 Cormorant, and the Royal Australian Air Force S-70A-9. Simula developed and/or manufactured crashworthy seats for several commercial aircraft as well, including the Bell 212, 412, 230, 430, 427, the 609 tilt-rotor, and the Kaman K-MAX, helicopters.
Stan remained very interested in research and continued to study human tolerance, energy absorber design, and other crash survivability topics supported by contracts awarded to Simula by the US Army and US Navy. Two of those contracts placed years apart involved rewriting and updating the Crash Survival Design Guide which served as a primary resource of aviation crash survival information and as a guide for the design of crashworthy features of aircraft. His work advanced energy absorber technology to include adjustable-constant-load energy absorbers, profile load energy absorbers, and adjustable profile energy absorbers. Having adjustability in the seat energy absorbers became particularly important because as women joined the aircrew population, the range of occupant weights to be protected expanded substantially.
Simula also conducted research on inflatable restraint systems for helicopters which led to the development of airbag systems. Inflatable restraint systems were installed in the UH-60 Blackhawk and the OH-58 Kiowa. The airbag system was credited by the Army Safety Center for saving several lives in OH-58 crashes. An offshoot of that research was a patent for an inflatable tubular structure used as a head restraint. This airbag technology, implemented by inflating and deploying a tubular structure across the side window or door, led to the automotive side impact head protection systems currently used in automobiles.
In 2003, Simula was bought out by Armor Holdings, a corporate investment company, which in turn was acquired by BAE in 2007. In 2002, Stan started another company, Safe, Inc, to continue research in energy absorbing seats and other safety-related technologies primarily through the Small Business Innovative Research (SBIR) program. Of particular interest was finding a low cost, lightweight, and automatic method to adjust the stroking force of seats to the occupant’s weight. With the possibility of predictive crash sensors, this research was expanded to include the possibility of not only adjusting the seat to the occupant but also to the severity of the impending (predicted) crash, thus optimizing the stroking force and further reducing the chance of injury to an absolute minimum. Safe is currently involved in developing an advanced energy absorbing system for the Future Vertical Lift aircraft and for a new gunner’s seat for retrofit into the Navy’s H-60 aircraft selectively using all or portions of the latest technology.
Safe, Inc is also currently developing technology to protect the crews of two different space capsules. The Crew Impact Attenuation System in the Lockheed Martin Orion capsule uses Safe’s Selectable Profile Energy Absorber system to protect the crew in the event of a hard landing. The Boeing entry into the commercial capsule competition also uses energy absorption technology developed and fabricated by Safe. The two systems are very different but accomplish the same end, that of protecting the module occupants from the consequences of a hard landing.
In addition to starting two businesses which remain operational, Stan has contributed to helicopter safety throughout his career. For these contributions, Stan has been recognized with an Honorary Doctorate degree from his alma mater, the University of Idaho, in 2010. Stan also received a VFS special award for advancing technology and products in the area of aircrew and passenger safety. Simula was part of the team that won the 2001 VFS Harry T. Jensen award for conducting a full-scale helicopter drop into the water. He also is and has been, a member of VFS’s Crashworthiness Committee for several years. Stan is a past-president of the Safety and Flight Equipment (SAFE) Association; and among other awards, has received the SAFE award in 1982 for his contributions to aircraft crash safety and the President’s award in 1992 for his contributions to the society.
Stan has presented 6 papers at VFS meetings and has published a paper in the Journal. He has authored or co-authored 26 other papers and technical reports. Stan was awarded four patents on rocket-related work at Thiokol and two patents related to energy absorption technology while at Simula. In addition to designing and developing seats and restraint systems, Stan has been active in establishing values for spinal injury tolerance in the early development of stroking seats and has continued to work on refining the injury tolerance values to cover all potential seat occupants. With the work that Safe, Inc is doing to develop energy absorbing hardware for two different space vehicles, Stan’s career reconnects with his earlier background work with rockets. In addition to his contribution to helicopters, he has contributed to technology applications covering the gamut of automobiles, transport aircraft, and spacecraft. Stan has devoted his professional career to developing technology and hardware to eliminate or reduce the severity of the injury of those involved in crashes of rotary-wing aircraft as well as other forms of transportation.
Written by Lance Labun