Date: 201509
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Light Transport
Operator: Air Taxi
Operating under: Part 135
Flight plan: IFR
Mission: Cargo / Freight / Delivery
Flight phase: Parked
Aircraft component: Turbine Engine
Component problem: Malfunctioning
Reporter organization: Air Taxi
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Flight Instructor; Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Commercial
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Maintenance
Detector: Person Maintenance; Person Flight Crew
When detected: In-flight; Routine Inspection
Result: General Maintenance Action
Contributing factors: Human Factors; Procedure; Aircraft
Primary problem: Aircraft

Narrative: I am a First Officer on a part 135 on-demand operation. I was called in for a flight to recover another aircraft that had mechanical issues. The flight would take place in aircraft Y. The captain and I along with a mechanic were to fly aircraft Y to ZZZ and surrender aircraft Y to the crew that had broken down there. The mechanic we had flown to ZZZ would then fix the broken aircraft (aircraft X) so that the captain and I could return aircraft X to base.Aircraft X is contracted on feeder routes hauling cargo. After loading the cargo aircraft X departed ZZZ. During the departure phase of flight the crew of two captains noticed a low oil pressure indication on the number one (left) engine. They shut down the engine and returned to land at ZZZ. This is when the captain; mechanic and I were called out to fly to ZZZ on a recovery flight.When we arrived at ZZZ in aircraft Y we promptly unloaded aircraft X and loaded the cargo onto aircraft Y. The two captain crew informed my captain and I of what had happened to aircraft X then departed ZZZ in aircraft Y. The captain and I then waited at the FBO for several hours while the mechanic looked into the issue with aircraft X. After several hours the mechanic determined that that there was an oil leak caused from a bad seal and that parts would have to be ordered. All three of us then went and stayed at a local hotel for the night.The mechanic was called by work the next morning to return to ZZZ and fix aircraft X. The captain and I were never called in because the company did not want our duty day to start until aircraft X was fixed. Later in the day; the mechanic informed the company flight following that aircraft X was fixed and the captain and I were called in for a flight. We were never given the chance to 'run up' or test the aircraft before flight.The Captain; mechanic and I departed ZZZ destined for ZZZ1. During the climb it was noted that the oil pressure was higher than normal on the number one engine; but still inside operating limits. Once reaching our cruise altitude the oil pressure continued to climb; to point where it was well above the red line indication on the gauge. The captain and I discussed the issue with the mechanic and decided to pull the power back on the engine to keep it within limits and continue to ZZZ1. It was also noted that number one engine oil temperature was erratic; showing high temperatures at times but 'bouncing' all over the place.Once we reached ZZZ1 the Captain and mechanic relayed the information to the mechanics at ZZZ1. The ZZZ1 mechanics removed aircraft X's oil filter and oil screen revealing large amounts of metal chunks; flakes; and dust. The mechanics then informed the captain and me that they had cleaned large amounts of metal from the aircraft engine oil system several other times; but had continued to let the aircraft fly.It was also noted that the mechanic that flew jump seat on Aircraft Y worked second shift. At the time the call came in for the recovery flight the mechanic was just finishing his shift. He then flew jump seat to ZZZ and worked on aircraft X for several hours putting his work day well over 24 hours on duty and certainly impairing his work.




Synopsis: Small jet First Officer describes the shoddy maintenance practices of the company he works for. An engine that had low oil pressure was 'repaired' and the crew tasked to ferry the aircraft back to base. The engine exhibits high oil pressure and erratic oil temperature in flight and is operated at reduced thrust to return to base. Mechanics removed the oil filter and oil screen revealing large amounts of metal chunks; flakes; and dust and informed the crew that they had cleaned metal from the oil system several times before.