NHTSA Complaint #11522762 — 2020 FREIGHTLINER CASCADIA

Ascending Tehachapi Pass CA Hwy 58 Eastbound in the left lane grossing 45,000lbs and traveling at 55mph with cruise control ON. I was passing another slower moving truck(~35-40mph). Before I came along the other vehicle the highway curved to the left. The Collision Aviodance System(CAS) didn't alarm, however the cruise control cut power and Automatic Emergency Braking(AEB) hardbraked my truck reducing the speed from 55mph to 40-45mph. This was sudden and unexpected. Once I determined the issue, I applied throttle overriding the AEB/CAS. However my forward momentum was lost and accelerating uphill was slow. It was midday and clear skies. No one was following me fortunately, but sudden and unexpected braking could have had a vehicle tailing too closely(It was an uphill grade with a speed limit of 65 mph for POV) rear-end my trailer(48 foot stepdeck trailer). Please explain to me how CAS/AEB are safety systems for a CMV?!? This is the 4th report I have filed with NHTSA about the same Freightliner Cascadia tractor. According to the vehicle operating Manual that this occurrence of unexplained and unwarranted braking is a "feature" of this "safety system". Meaning that the CAS/AEB was functioning as designed(A flawed designed in my professional opinion). I have been contacted by the NHTSA about previous filed report about an ongoing investigation with the manufacturer. What action is this agency going to take? Will there be an investigation when the system performs as designed causing an avoidable accident, injury, or death? Will I be a defendant, witness, or victim? Sincerely, [XXX] Junction City, Oregon INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).