What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) While enroute on a FAA proving run from denton, TX to ft. lauderdale, FL smoke was reported in the cockpit, mask was deployed and aircraft divereted to Shreveport, LA and landed without further incident. Troubleshooting of aircraft found that some hydraulic fluid had been spilled near or in an environmental duct during previous hydraulic maintenance. When the aircraft was in flight and pressurized, the fluid started to smoke in the ducts and was blown into the cabin. No problems reported after the duct was cleaned and aircraft test run. Aircraft was returned to service and flown back to denton, TX without further problems.
As the FAA filed it
(-23) WHILE ENROUTE ON A FAA PROVING RUN FROM DENTON, TX TO FT. LAUDERDALE, FL SMOKE WAS REPORTED IN THE COCKPIT, MASK WAS DEPLOYED AND AIRCRAFT DIVERETED TO SHREVEPORT, LA AND LANDED WITHOUT FURTHER INCIDENT. TROUBLESHOOTING OF AIRCRAFT FOUND THAT SOME HYDRAULIC FLUID HAD BEEN SPILLED NEAR OR IN AN ENVIRONMENTAL DUCT DURING PREVIOUS HYDRAULIC MAINTENANCE. WHEN THE AIRCRAFT WAS IN FLIGHT AND PRESSURIZED, THE FLUID STARTED TO SMOKE IN THE DUCTS AND WAS BLOWN INTO THE CABIN. NO PROBLEMS REPORTED AFTER THE DUCT WAS CLEANED AND AIRCRAFT TEST RUN. AIRCRAFT WAS RETURNED TO SERVICE AND FLOWN BACK TO DENTON, TX WITHOUT FURTHER PROBLEMS.