Narrative:

While working the arrival sector from the west side of the airspace; we had just changed configurations to one that we haven''t used in quite some time. I had aircraft X from the northwest check in at the same time another aircraft from the southwest checked in; and they had stepped on each other. I reached out to aircraft X and gave them a vector of 130 degrees and thought I descended them to 11;000 feet. They were taken off of the arrival to be vectored to the final approach course. I went back to the second aircraft from the southwest and issued them instructions and a descent to 8;000 feet. Just as these two aircraft were checking in; I was giving a relief briefing to the controller taking the position. I didn't think anything of it because the altitude that we issue are standard for the most part; and didn't think that I did anything out of the ordinary. Apparently I gave aircraft X descent to 8;000 feet in a 9;500 foot minimum vectoring altitude (MVA). The typical altitude to descend to is 11;000 feet to stay above the terrain; and sequence with other aircraft. After finally leaving the position the aircraft apparently descended below the 11;000 feet and at 9;700 feet the next controller asked for their assigned altitude. They said 8;000 feet. Apparently after reviewing I issued 8;000 feet instead of the 11;000 feet that I normally do. The relieving controller question the pilot at 9;700 feet in the 9;500 foot MVA; and instructed the pilot to climb back up. The pilot descended about 200 feet below the MVA before climbing back up. Thanks to the relieving controller recognizing the descent.I allowed myself to be distracted by two aircraft checking in at the same time as well as trying to conduct a relief briefing. During this configuration three of the four fixes normally get descended down to 8;000 feet; except for this fix. Apparently I got into the habit of issuing the 8;000 feet and didn't think anything of it. During the relief briefing I told the guy relieving me that the pilot was descending to 11;000 feet. I got caught up in the expectation bias that I always descend to 11;000 feet and thought that I did this time as well. I got complacent with ensuring the read back during the relief briefing and the two aircraft checking in. I also allowed myself to get into the habit of issuing altitudes based on what I do the majority of the time; as opposed to this random configuration. Just need to slow down and ensure the correct altitudes are issued for the correct fixes and configurations.

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Original NASA ASRS Text

Title: L30 TRACON Controller reported they descended an aircraft to an altitude below the Minimum Vectoring Altitude.

Narrative: While working the arrival sector from the west side of the airspace; we had just changed configurations to one that we haven''t used in quite some time. I had Aircraft X from the northwest check in at the same time another aircraft from the southwest checked in; and they had stepped on each other. I reached out to Aircraft X and gave them a vector of 130 degrees and thought I descended them to 11;000 feet. They were taken off of the arrival to be vectored to the final approach course. I went back to the second aircraft from the southwest and issued them instructions and a descent to 8;000 feet. Just as these two aircraft were checking in; I was giving a relief briefing to the controller taking the position. I didn't think anything of it because the altitude that we issue are standard for the most part; and didn't think that I did anything out of the ordinary. Apparently I gave Aircraft X descent to 8;000 feet in a 9;500 foot Minimum Vectoring Altitude (MVA). The typical altitude to descend to is 11;000 feet to stay above the terrain; and sequence with other aircraft. After finally leaving the position the aircraft apparently descended below the 11;000 feet and at 9;700 feet the next controller asked for their assigned altitude. They said 8;000 feet. Apparently after reviewing I issued 8;000 feet instead of the 11;000 feet that I normally do. The relieving controller question the pilot at 9;700 feet in the 9;500 foot MVA; and instructed the pilot to climb back up. The pilot descended about 200 feet below the MVA before climbing back up. Thanks to the relieving controller recognizing the descent.I allowed myself to be distracted by two aircraft checking in at the same time as well as trying to conduct a relief briefing. During this configuration three of the four fixes normally get descended down to 8;000 feet; except for this fix. Apparently I got into the habit of issuing the 8;000 feet and didn't think anything of it. During the relief briefing I told the guy relieving me that the pilot was descending to 11;000 feet. I got caught up in the expectation bias that I always descend to 11;000 feet and thought that I did this time as well. I got complacent with ensuring the read back during the relief briefing and the two aircraft checking in. I also allowed myself to get into the habit of issuing altitudes based on what I do the majority of the time; as opposed to this random configuration. Just need to slow down and ensure the correct altitudes are issued for the correct fixes and configurations.

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.