C-208B air carrier flight crew reported an engine malfunction just after becoming airborne after takeoff from a non-towered airport. The Captain took the controls and landed on the remaining runway; then taxied to the terminal.
Synopsis
C-208B air carrier flight crew reported an engine malfunction just after becoming airborne after takeoff from a non-towered airport. The Captain took the controls and landed on the remaining runway; then taxied to the terminal.
Narrative
During our takeoff roll on RWYXX; the First Officer; who was the Pilot Flying; set the takeoff power to just below 1700 torque and announced; 'set take off power.' I observed the power was around 1500 and adjusted the power lever to approximately 1800; then made a small adjustment back to 1700.Around 70-75 knots; the First Officer moved his hand from the power lever to the yoke to rotate; which went smoothly. However; immediately after becoming airborne; the plane shuddered; and the power rapidly decreased to between 1200-1000 pounds of torque. The power continued to fall even as I tried to increase it.I immediately identified the torque issue and; assessing the remaining runway; decided to abort the takeoff. I took control; called 'my controls;' pitched the plane down; and pulled the power lever back to idle. Once back on the runway; I initiated reverse thrust and began braking. The First Officer assisted with the brakes as we neared the end of the runway.After we stopped and turned around; the engine indications appeared normal; so we taxied the plane back to the terminal without any further issues.The passengers were briefed about the incident and appeared to be thankful; calm; and understanding.Later; after starting the aircraft to taxi to a different location on the ramp; the power was rolling uncontrollably backward from approximately 400 to 180.
Second reporter narrative
On Day 0 while acting as a First Officer and Second in Command for a 135 passenger carrier; my Captain and I prepared to depart from ZZZ. I was the Pilot Flying on the leg and he was the Pilot Monitoring. I listened to the weather prior to passengers boarding. The skies were clear for our purposes and visibility 10 miles. The winds were at 6 knots and variable. After an unremarkable engine start; we repositioned on the ramp and held short of the taxi and runway. I listened to the weather again which no reported winds at 5 knots and variable. While in this holding position we both observed the wind sock on the approach end of RWY which was indicating XX was the preferred runway. We decided we would take off of Runway XX; and rotate at 75 for the variable winds. We made a radio call on the CTAF and proceeded to back taxi. Once in position on the threshold markings I applied power with nothing of note. I looked at the analog gauge and saw the needle was touching the bottom of the 1700 pounds position. I called for the Captain to 'set take off power' and lowered my hand to the base of the throttle quadrant where my finger rested on the groove for the power lever. I believe I heard a small power adjustment; which I would later learn was the captain increasing the power from 1500 pounds back up through 1700 pounds and to 1800 pounds. These number are well within our limitations. As I rotated; I took my hand off the throttle quadrant and used both hands on the yoke. I felt a slight power decrease and then an increase. This was an additional power adjustment by the captain. As I lifted off the ground and was 5-10 feet in the air I felt a strong shudder. Immediately after that a rapid decrease in torque. I learned after the fact; that this massive power decrease rolled our torque back to around 1000 pounds while the Captain was advancing the power lever. I did not observe the torque or other instruments as my focus was outside of the aircraft; however; it was audible and felt. I felt a buffet like sensation and the Captain yelled 'My controls' as he pitched down. I saw his hand then pull the power lever back to idle as he pitched us to land back on the remaining runway. He placed the aircraft down safely and began to brake and use the remaining power we had to reverse. I called out 'I'm on the brakes with you' and got on the brakes with him. We came to a stop on the approach end numbering for Runway XY.At a low power setting we taxied back to the ramp. We debriefed the passengers and de-planed them without incident. The landing was safe; coordinated; and did not fall outside the parameters of a normal landing with the exception of the braking action.After the incident the Company determined the Fuel Control Unit (FCU) was most likely at fault and advised us they would replace the FCU and the starter. The FCU was replaced that day due to the loss of power.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.