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Recall of 2.6M GM vehicles after 34 crashes and 12 deaths The recall had sparked investigations by US Congress, federal regulators, the Department of Justice and GM itself. All are asking why it took General Motor (GM) so long to address an issue first noted by the company in 2001. Some of the vexing questions looming over General Motors' decade long failure to recall cars with a deadly ignition-switch defect were coming under the spotlights. |
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Consulting materials engineer Mark Hood shows the ignition assembly that has a faulty ignition switch (black piece at left), in the mechanical testing laboratory at McSwain Engineering Inc. in Pensacola, Fla. The firm helped to conduct the engineering investigations and failure analysis that resulted in the GM recall. |
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The National Highway Traffic Safety Administration confirmed on 3 April it continues to receive answers and documentation from GM regarding the ignition switch recall, but has yet to release a timetable on when the information will be made public. GM said it has submitted 200,000 pages of records and answered more than 65% of the 107 questions National Highway Traffic Safety Administration (NHTSA) has asked about the events leading to the recall. Amid a wave of lawsuits and media coverage, four central issues have emerged that bear the closest watching these coming weeks. How GM's multiple internal investigations failed to lead to a recall sooner The switch's potential to shut off the engine should have earned it a "priority 1" designation in the system, reserved for safety concerns or issues that could delay production. Yet each time engineers opened a PRTS inquiry into the faulty switch, they either did nothing or settled on remedial action that failed to grasp the safety-critical nature of the problem, GM's report to regulators shows. For example, GM told regulators that in 2004, its engineers were able to replicate an incident in which a Cobalt model vehicle lost power because the switch moved out of the run position. Engineers proposed several possible solutions, but the inquiry later was closed without action. GM confirmed in a timeline submitted to NHTSA in February that the PRTS was closed "after consideration of the lead time required, cost and effectiveness of these solutions." Several of NHTSA's 107 questions to GM relate to that apparent dropped ball and likely foreshadow the sort of questions that awaited GM CEO. The answers could help explain how much GM's processes were to blame for the delayed recall or whether one or more bad actors foiled earlier action. Why NHTSA failed to launch an investigation, despite signs that a faulty switch might be causing airbags not to deploy NHTSA officials met with GM employees in March 2007 to discuss passive restraint systems, such as airbags, according to GM's timeline. At that meeting, the officials mentioned a NHTSA-commissioned investigation into a July 2005 crash in Maryland in which the airbags in a 2005 Cobalt did not deploy. They noted the car's ignition was in the "accessory" position at the time of the crash. The connection between the airbag and the ignition may not have been obvious to NHTSA. Experts say the interaction between the ignition position and airbag deployment depends on the way airbag systems are programmed and varies from company to company. GM, for its part, seems to have recognized a link. The company started a legal file and assigned an employee to track down crashes in which airbags didn't deploy. But apparently, NHTSA didn't make the same logical leap. GM's chronology mentions no further contact from the agency. Why not? Members of Congress are pushing NHTSA to answer this question in the coming hearings. It will be key in determining how much of the blame for GM's long-delayed recall should rest on the government's shoulders. Whether and how GM's vehicle-safety protocols have changed But overarching those issues are more fundamental questions: Are GM's processes better today? What are the risks of another deadly safety flaw slipping through GM's sprawling product-development enterprise? Lawmakers, regulators and consumers will want to know whether they can believe GM CEO’ promise, made in a video message to consumers last week, that GM "will not let it ever happen again." GM hasn't offered specifics about how the company will improve vehicle safety, beyond naming a GM veteran in March to the newly created post of global safety chief. NHTSA wants specifics, and lawmakers likely will, too. In NHTSA's demand for more information from GM, due 3 April, it asks GM to "detail the ways in which" the process fell short and to describe "GM's plans to change its process." The answers will shed light on how far GM's safety system and protocols need to go for Barra to make good on her promise. GM has launched a website, www.gmignitionupdate.com, to provide consumers with information on the recall. Whether GM's internal processes were violated or laws were broken |
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The sources and other observers have zeroed in on a redesign of the faulty ignition switch that was approved in April 2006 for the 2007 Cobalts. Why wasn't the part number changed for the redesigned part, leaving GM engineers’ years later fumbling to explain why models after 2007 had different switches from older cars -- and prompting Friday's expanded recall? |
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March end action was aimed at ferreting out faulty replacement parts that may have been installed in cars originally built with the correct switch. GM's account of that decision and others is sparing: It says simply that the supplier proposed the change, and the engineer responsible for the part signed off on it. NHTSA wants to know more: Who was the engineer who signed off? Why was the change made? Who else knew about it? It has asked for all documents related to the redesign, too. Those answers ultimately could dictate whether GM's ignition-switch recall leads to new laws or regulations meant to prevent future defects from slipping through. The cost to Recall |
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Plastics as a lightweight alternative in Automobiles Plastics parts have been widely applied in the passenger compartment of any model of vehicle. The plastic car parts industries demonstrate great weight savings (for fuel efficiency). To replace its heavier metal counterpart in production car models of 200,000 or more units a year, the production time needs to be closer to the speed of a metal stamping machine. The plastics and automotive industry know that manufacturing speed can be covered – plastics are about 50% of the volume of today’s vehicles because a dashboard or bumper guard can be created about as fast as a milk jug can be made. So let’s report to the strength. The Tensile Strength vs Density Chart proved that plastics by themselves (with no fill) can be a lot stronger than the public may well believe. However, there are ways to make plastics even stronger, by filling the molten material with various fibers. Like rebar in a cement pillar or the weave of thread in cloth, filling resin with fibers provides added strength. Short (chopped) glass fibers have been used since the 1950s to give greater strength to plastic car parts, and last year the industry validated research to predict the strength and functionality of glass-filled high cycle time injection molded processing. Corporate Average Fuel Economy (CAFE) standards set by the National Highway Traffic Safety Administration and the U.S. EPA require automakers to achieve fuel efficiency of more than 50 mpg by 2025. Automakers are increasingly looking to plastics as a lightweight alternative to traditional materials; carbon fiber-reinforced composites, for example, are 50 percent lighter than conventional steel and 30 percent lighter than aluminum, according to the Plastics and Polymer Composites Technology Roadmap for Automotive Markets (Roadmap). There’s so much pressure put on the OEMs at this point to be able to meet the new CAFE standards … that the value that plastics and composites are able to bring with their strength-to weight ratio, stiffness-to-weight ratio, becomes even more important, as noted by the chair of the American Chemistry Council (ACC)’s automotive team in a phone interview with Plastics News. The ACC chair said he’s seen the use of plastics in automotive applications double during his 20 years in the industry, but challenges remain for plastics to fully realize their potential. The automotive infrastructure and workforce have evolved over the past 100 years to accommodate metals, creating barriers to plastics and polymer composites as discussed by in the Roadmap. The roadmap calls for more high-profile demonstrations of the capabilities of plastics and polymer composites throughout the supply chain, as well as actions to enhance the system of information around plastics. The important piece is to get industry-wide demonstrations, applications and projects identified and working collaboratively with the supply chain, whether it’s tiers or OEMs, showing what the engineers are capable of supplying with the lightweight materials with plastics and composites,” Marks said. “Another area is in the area of material selection and part design. By showing the engineers what you can do with the lightweight materials, with the low specific gravity, high strength, high stiffness that’s capable with some of the polymer composite materials, they’re able to substitute what you would consider traditional materials by making them lighter weight.” In addition to demonstrations and workforce development, there is the need to enhance the knowledge base around plastics through more educational programs for plastics and polymers at the university level. The roadmap also identifies a challenge in the perception that plastics and polymer composites are not a “premium” material. Developing better tools to model plastic and polymer composite designs will help change this perception, as well as reducing development time to make plastics and polymer composites a more attractive alternative. Though issues continue to be addressed in multi-materials joining and assembly, difficulty in end-of-life recycling and the high cost of some materials, plastics and polymer composites offer a big advantage in the ability to consolidate parts for dramatic weight savings. |
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For example, a single injection-molded plastic part “one piece” was developed for the front end module of the Ford Taurus, representing a mass reduction of 46 percent, according to ACC. |
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The ability for parts to be integrated through the injection molding process allows those extra pieces to be eliminated from the manufacturing process. So it takes out the cost, it takes out the mass associated with that. HKPC Injection molding technology The project team has demonstrated the important deliverables below:
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