Investigations
Failed School Bus Seat Back Pans
NHTSA Preliminary Evaluation PE17004 - closed, opened 2017-09-12.
NHTSA investigation PE17004 is a Preliminary Evaluation opened on 2017-09-12 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2018-12-04 - NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.
A Preliminary Evaluation like PE17004 is the entry point of the federal defect-investigation process. NHTSA engineers scan complaint databases, field reports, and manufacturer data to decide whether an Engineering Analysis is warranted, whether a voluntary recall is already sufficient, or whether the pattern does not rise to a defect finding.
Investigators summarized the matter as follows: "On July 7, 2017, the Office of Defects Investigation (ODI) received a report from an executive officer of the State of Iowa's Bureau of Finance, Facilities, Operations & Transportation Services, informing ODI of numerous..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time.
Investigation Summary
On July 7, 2017, the Office of Defects Investigation (ODI) received a report from an executive officer of the State of Iowa's Bureau of Finance, Facilities, Operations & Transportation Services, informing ODI of numerous seat back pan weld failures (pan material fatiguing at weld points) in multiple 2011 model year (MY) Navistar IC school buses. In August 2017, ODI engineers found similar failures when they visited an Arlington, Virginia public school facility to inspect buses ranging from MY 2011 to 2015. The first MY2011 bus inspected demonstrated the same issue (broken back seat pan welds) as reported on the Iowa buses. MY2012 - MY2015 buses did not demonstrate the failed seat back pan issue. NHTSA discovered that these buses had a different seat back pan design. ODI opened this investigation to better understand the potential risk of injury and evaluate passenger compartmentalization in the event of a crash involving a subject vehicle containing broken seat back pan welds. Navistar conducted sled testing at the Transportation Research Center of Ohio (TRC) to better understand if broken seat back pan welds could lead to a loss of passenger compartmentalization in a crash. ODI engineers were present and observed all tests done by the manufacturer. Although the test results indicated that passengers would remain compartmentalized, upon further review, ODI became concerned that the test manikin's necks seemed to over-extend when their heads struck the seat back frame and the torso pushed into the seat back pan. There was a concern that injuries may occur as a result of the broken seat back pan welds, allowing the passenger torso to push further into the seat back than if good welds were in place. Upon NHTSA's request, Navistar ran additional sled tests with instrumented test manikins to measure injury potential in the head, neck, and chest. The tests were conducted using Federal Motor Vehicle Standard (FMVSS) 208 as a guide and reference as there are not specific st
About This Investigation Type
A Preliminary Evaluation (PE) is the first phase of NHTSA's investigation process. It is opened when the agency identifies a potential safety defect pattern, usually triggered by consumer complaints, manufacturer reports, or field monitoring. During a PE, NHTSA gathers information to determine whether a formal engineering analysis is warranted.
Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. about how PlainCars sources NHTSA data.
Read our methodology - how this data is sourced, computed, and verified.