Narrative:

I experienced a significant in flight oil loss in a cirrus SR22T aircraft. On the flight from ZZZ to ZZZ1 airport about 20 minutes into the flight; at 5;500 feet; running at 75% power cruise; the aircraft oil pressure gauge showed a lower then normal oil pressure reading of about 37 psi. Still in the green arc but low for this power setting. In the next few minutes I monitor the oil pressure gauge closing and noticed it very gradually move down to 32 psi (very close to the bottom of the green arc). I then move the mixture to full rich to see if that would have help with the oil pressure. It in fact made it worst as aircraft started some slight propeller RPM surging. At this moment I contacted TRACON; moved throttle to idle and started a VFR decent to ZZZ2 airport (which was less then 5 nm away). The oil pressure went into yellow arc. Keeping the throttle at idle for rest of descent flight; I spiraled down to a landing at ZZZ2; I was handed over to tower who were very accommodating in giving me priory to my choice of runway 25R. The engine never quit; and I had enough power to taxi off the runway. Upon exiting aircraft it was evident of the significant oil loss. The oil cap was securely on; the top of engine was clean of oil. The dip stick was showing approximately 2 quarts of oil left. It appeared most of all the oil had exited the pilot side exhaust. Aircraft has 23.2 flight tact hours since it's annual inspection. The start of the flight showed 6 3/4 qt of mineral oil.

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Original NASA ASRS Text

Title: Cirrus SR22 pilot reported an engine oil pressure anomaly which necessitated a diversion to the nearest suitable airport.

Narrative: I experienced a significant in flight oil loss in a Cirrus SR22T aircraft. On the flight from ZZZ to ZZZ1 airport about 20 minutes into the flight; at 5;500 feet; running at 75% power cruise; the aircraft oil pressure gauge showed a lower then normal oil pressure reading of about 37 PSI. Still in the green arc but low for this power setting. In the next few minutes I monitor the oil pressure gauge closing and noticed it very gradually move down to 32 PSI (very close to the bottom of the green arc). I then move the mixture to full rich to see if that would have help with the oil pressure. It in fact made it worst as aircraft started some slight propeller RPM surging. At this moment I contacted TRACON; moved throttle to idle and started a VFR decent to ZZZ2 airport (which was less then 5 nm away). The oil pressure went into yellow arc. Keeping the throttle at idle for rest of descent flight; I spiraled down to a landing at ZZZ2; I was handed over to Tower who were very accommodating in giving me priory to my choice of Runway 25R. The engine never quit; and I had enough power to taxi off the runway. Upon exiting aircraft it was evident of the significant oil loss. The oil cap was securely on; the top of engine was clean of oil. The dip stick was showing approximately 2 quarts of oil left. It appeared most of all the oil had exited the pilot side exhaust. Aircraft has 23.2 flight tact hours since it's annual inspection. The start of the flight showed 6 3/4 qt of mineral oil.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.