The 34-year-old Dane was making his seventh start in the iconic race. Driving the No. 95 Aston Martin Vantage, Simonsen crashed in the Tertre Rouge corner of the Circuit de la Sarthe at Le Mans, France.
"The driver was immediately attended on the scene by the doctors from the Automobile Club de l’Ouest’s Medical Service," an official statement from the race organizers said.
"In a serious condition, Allan Simonsen was transferred immediately to the Circuit Medical Centre where he died soon after due to his injuries.
"Allan Simonsen’s family has been informed immediately by David Richards, Principal of the Aston Martin Racing team."
After starting first in the LM GTE Am class, Simonsen's car appeared to snap loose on the damp and slick track, then immediately turned back to the left has he corrected and slid into a steel barrier.
The race continued behind a safety car for almost an hour following the crash while the barrier was repaired. A tree sits behind the barrier where Simonsen crashed and the impact from the guardrail sheared bark off the tree.
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