An interesting side story for you sonikk4. This whole thing with the lawyers here in the US is sickening. When the Alaska Airlines Flight 261 crash occurred in 2000 and it was blamed on the failure of a jack screw that controlled the horizontal stabilizer, we at the Kennedy Space Center saw a common thread. We were having failures of jack screws on ground support equipment and inspections were not good enough to forecast replacements before a failure. So, very quickly, we came up with up a solution. A "Fail Safe and Continue to Operate" redundant nut system was devised for the jack screws that would meet our needs for the Space Shuttle equipment. The solution was offered to Federal Aviation Administration (FAA) and National Transportation and Safety Board (NTSB) that were investigating Alaska Airlines crash. Shortly after we were visited by lawyers interested in the development. We thought that they were there to help introduce the safety device into the main stream. We were wrong. They never told us who or what they were representing. But the bottom line of the crash investigation was to determine who was at fault; the airline that did not perform adequate maintenance of the aircraft or the aircraft designers that did not design out a failure mode.
In the end, the blame was placed on the airline poor maintenance practices. After that, the aircraft designers claimed that the "Acme Thread" jack screws were not being used on any new aircraft designs and the existing inspection practices were good enough for the existing fleet until it was decommissioned. There was no need to implement a redundant nut on anything. These conclusions were very frustrating for us.
http://www.iasa-intl...pdf/asw1118.pdf
https://en.wikipedia...ines_Flight_261