Narrative:

Aircraft X was doing a practice approach. Upon conclusion of his approach; I issued him direct leaving 3;700 feet which was the mia(minimum IFR altitude) to maintain 4;000 feet. After communications transfer to TRACON there was a mia of 4;100 feet that aircraft X clipped. The portion of flight through the elevated mia was about 3-5 miles. I didn't call TRACON at that point because the aircraft was going to exit the higher mia just as fast by remaining on course as a vector would and there was IFR traffic at 5;000 feet. I didn't realize the mia change until the MSAW (minimum safe altitude warning) went off. Maybe have an earlier MSAW alert before the aircraft penetrates it but it was my mistake.

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Original NASA ASRS Text

Title: A Center Controller reported they issued an aircraft a direct routing and did not realize the route was below the Minimum IFR Altitude.

Narrative: Aircraft X was doing a practice approach. Upon conclusion of his approach; I issued him direct leaving 3;700 feet which was the MIA(Minimum IFR Altitude) to maintain 4;000 feet. After communications transfer to TRACON there was a MIA of 4;100 feet that Aircraft X clipped. The portion of flight through the elevated MIA was about 3-5 miles. I didn't call TRACON at that point because the aircraft was going to exit the higher MIA just as fast by remaining on course as a vector would and there was IFR traffic at 5;000 feet. I didn't realize the MIA change until the MSAW (Minimum Safe Altitude Warning) went off. Maybe have an earlier MSAW alert before the aircraft penetrates it but it was my mistake.

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.