mind, we would remain vigilant and forever prevent foreign object debris from causing a problem. In fact, many factors combine to cause a chain of events that can lead to a failure." Studies There have only been two detailed studies of the economic cost of FOD for civil airline operations. The first was by Brad Bachtel of Boeing, who published a value of $4 billion USD per year. This top-down value was for several years the standard industry figure for the cost of FOD. The second work (2007) was by Iain McCreary from the consultancy Insight SRI Ltd. This more detailed report offered a first-cut of the cost of FOD, based on a bottom-up analysis of airline maintenance log records. Here, data was broken into per flight direct costs and per flight indirect costs for the top 300 global airports, with detailed footnotes on the supporting data. The Insight SRI research was a standard reference for 2007-2009 as it was the only source presenting costs and thus was quoted by regulators, airports, and technology providers alike. However, while that 2007 Insight SRI paper remains the best free public source of data, the new analysis (2010) from Insight SRI offers new numbers. The author of the new report (not free) says "Readers are cautioned not to rely on or in the future refer to numbers from the 2007-08 Insight SRI paper The Economic Cost of FOD to Airlines. This earlier effort was 'The' first document detailing the direct and indirect cost of FOD that was based on airline maintenance data (the entire document was a single page of data, followed by 8 pages of footnotes)." Per-flight direct costs of $26 are calculated by considering engine maintenance spending, tire replacements, and aircraft body damage. Per-flight indirect costs include a total of 33 individual categories: Airport efficiency losses Carbon / environmental issues Change of aircraft Close airport Close runway Corporate manslaughter/criminal liability Cost of corrective action Cost of hiring and training replacement Cost of rental or lease of replacement equipment Cost of restoration of order Cost of the investigation Delay for planes in air Delays at gate Fines and citations Fuel efficiency losses Hotels In-air go-around Increased insurance premiums Increased operating costs on remaining equipment Insurance deductibles Legal fees resulting Liability claims in excess of insurance Loss of aircraft Loss of business and damage to reputation Loss of productivity of injured personnel Loss