CAS' letter regards the Impala's airbag systems. In particular, it focuses on a piece of computer code that dictates when the airbags deploy, in the event of an accident. The problem, as CAS sees it, is that there may be a glitch in the airbag's algorithm that prevents the system from deploying if the seat's occupant bounces before the accident, lessening the amount of weight on the airbag sensor. Without the minimum amount of weight on the seat, the computer doesn't think there's anyone occupying it, and consequently, won't deploy an airbag.
According to CAS, there have been 143 people killed in front-impact crashes in 2000 to 2010 Impalas (CAS is, weirdly, including 2000 to 2002 Impala deaths, despite the fact that not all of those vehicles may feature the advanced airbag and flawed algorithim). Of those 143 deaths, only 98 were wearing seat belts. Eliminating 2000 to 2002 fatalities drops those figures to 132 and 89, respectively.
Finally, and perhaps most troubling, is CAS' study on the matter, which relies on the shaky data of the Fatality Analysis Report System - the same system that claimed there were 303 deaths due to the ignition switch recall. Basically, while there may be a problem with the algorithms, it certainly seems like CAS is asking a rather loaded question here.
We've included CAS executive director Ditlow's letter to NHTSA below. Scroll down, have a look, and let us know what you think.
The Honorable David J. Friedman
National Highway Traffic Safety Administration (NHTSA) 1200 New Jersey Avenue SE, West Building
Washington, D.C. 20590
Dear Administrator Friedman:
On about November 15, 2013, Don Friedman of Xprts LLC filed a defect petition (DP) with NHTSA on a defective algorithm in 2003-10 General Motors that can suppress airbag deployment by erroneously classifying the occupant weight as being too low to deploy the airbag. The Center for Auto Safety (CAS) is greatly concerned that there is no listing of a Defect Petition on the Agency's Website. Under Section 124(d) of the National Traffic and Motor Vehicle Safety Act (recodified at 49 USC § 30162(d), hereinafter Safety Act), NHTSA must grant or deny the petition within 120 days. Well over 120 days have passed since NHTSA received the petition so the Agency is in continuing violation of the Safety Act. (Attachment A shows no DP listed on NHTSA's investigation page.)
Mr. Friedman is not your average petitioner. He designed the guidance system for the Sidewinder missile, the Lunar Rover, and was the chief contractor for NHTSA's Minicars Safety Research Vehicle which provided 50-mph barrier equivalent crash protection. Mr Friedman has likely directed more dynamic vehicle crash tests than anyone outside the auto industry. In addition, he has been involved in evaluation of many hundreds of real world crashes. Like Mark Hood who uncovered the defective GM ignition switch in the Chevrolet Cobalt and its role in airbag non-deployment before NHTSA did, Mr. Friedman is an independent engineer who appears to have discovered a defective algorithm in GM advanced airbag vehicles before NHTSA did.
The defect in the algorithm is fairly simple as discovered by Mr. Friedman. "The algorithm for the weight of the passenger used the instantaneous weight to determine whether to inhibit the airbag deployment. [A vehicle] lift and bounce [can] momentarily reduce[d] the weight of the passenger to that of a small adult. Using a weight averaged over a few tens of seconds would have avoided suppressing the airbag and the resulting serious injury and fatality. Since the control module is field reprogrammable a simple recall and modifying a few lines of code can avoid repeat occurrences."
This is a design defect in every GM vehicle with the flawed algorithm. Even though the defect cases litigated by NHTSA under the Safety Act in the 1970's (see NHTSA Chief Counsel Frank Berndt memo) do not require a so-called "defect trend" as contrived by NHTSA today, existence of a design defect means every vehicle has the flaw.
In its analysis of airbags failing to deploy in crashes, NHTSA pointed to FARS as a good starting point to find crashes which may point to a defect. While FARS cannot pinpoint the precise failure mode in a crash such as a flawed algorithm, FARS can pinpoint cases to examine to find such failure ￼modes. From Calendar Year 2000 when GM could have introduced advanced airbag vehicles with the flawed algorithm just through 2010, there were 143 frontal impact fatalities in model year 2000 to 2010 Chevrolet Impalas where the airbags failed to deploy with 98 of the fatalities being occupants who were lap/shoulder belted. (Attachment B.) We call on NHTSA to examine each of the fatal non-deployment crashes to determine whether the airbag should have deployed and why it didn't.
The Center is deeply troubled that NHTSA once again may have missed an advanced airbag like it did with the Cobalt. The Center is even more troubled that once again NHTSA has kept whatever it is doing secret behind closed doors even though there is a specific legal requirement for NHTSA to make its activities public.
The Center requests NHTSA to immediately grant or deny the defect petition filed by Mr. Friedman and Xprts as required by the Safety Act.
Clarence Ditlow Executive Director