MISSOULA, Mont. (AP) — Montana Rail Link says it has ruled out human error as the cause of a July train derailment in western Montana that spilled and destroyed six Boeing 737 fuselages.

Rail spokesman Jim Lewis told the Missoulian (http://bit.ly/13Nmmej ) in a story Thursday that simulations performed by a contractor hired by Montana Rail Link were inconclusive but suggested an issue with the tracks.

The Federal Railroad Administration requires railroads to investigate derailments. Spokesman Mike Booth said the results are then used as part of the federal agency’s investigation, which could take up to a year to complete.

The 19-car derailment occurred on July 3 as the fuselages were being shipped from Spirit AeroSystems in Wichita, Kansas, to Renton, Washington.

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Information from: Missoulian, http://www.missoulian.com

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