Quoting from the Executive Summary of the NTSB Accident Report:
On April 12, 2007, about 0043 eastern daylight time, a Bombardier/Canadair Regional Jet (CRJ) CL600-2B19, N8905F, operated as Pinnacle Airlines flight 4712, ran off the departure end of runway 28 after landing at Cherry Capital Airport (TVC), Traverse City, Michigan. There were no injuries among the 49 passengers (including 3 lap-held infants) and 3 crewmembers, and the aircraft was substantially damaged. Weather was reported as snowing. The airplane was being operated under the provisions of 14 Code of Federal Regulations Part 121 and had departed from Minneapolis-St. Paul International (Wold-Chamberlain) Airport, Minneapolis, Minnesota, about 2153 central daylight time. Instrument meteorological conditions prevailed at the time of the accident flight, which operated on an instrument flight rules flight plan.As a result of the investigation of this accident, the NTSB made recommendations to the Federal Aviation Administration in the following areas: the pilots' actions and decision-making during the approach, landing, and landing roll; landing distance assessment training; weather and field condition information and ground operations personnel communications; criteria for runway closures in snow and ice conditions; and alcohol testing.
The National Transportation Safety Board determines that the probable cause of this accident was the pilots’ decision to land at TVC without performing a required landing distance assessment based on runway contamination initially reported by TVC ground operations personnel and continuing reports of deteriorating weather and runway conditions throughout the approach. This poor decision-making likely reflected the effects of fatigue produced by a long, demanding duty day, and, for the captain, the duties associated with check airman functions.
Contributing to the accident were 1) the Federal Aviation Administration pilot flight and duty time regulations that permitted the pilots’ long, demanding duty day and 2) the TVC operations supervisor’s use of ambiguous and unspecific radio phraseology in providing runway braking information.
The safety issues discussed in this report include the pilots’ actions and decision‑making during the approach, landing, and landing roll; pilot fatigue and line check airman duty time regulations; weather and field condition information and ground operations personnel communications; and criteria for runway closures in snow and ice conditions. [NTSB/AAR-0802]
Editor's Note: Before anyone jumps to any conclusions about the 'alcohol testing' item among the NTSB's recommendations, please note that it arose because the investigation showed that, while both pilots tested negative for illicit drugs, they were not tested for alcohol after the accident. This was an omission on the part of the airline. The text of the NTSB report clearly states, "Although there is no reason to believe their performance was affected by alcohol, the failure of the airline to perform required postaccident alcohol tests prevents a definitive statement on the issue."
Here is the link to the full text of the Synopsis Report: NTSB/AAR-08/02. The full report will be available on the NTSB website in several weeks.