Boi TRACON controller descended an aircraft to an altitude below the MVA.

Attributes
ACN	1389642
Time
Date	201609
Local Time Of Day	1201-1800
Place
Locale Reference	BOI.TRACON
State Reference	ID
Environment
Light	Daylight
Aircraft 1
Make Model Name	Medium Large Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Person 1
Function	Approach
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 4
Events
Anomaly	ATC Issue All Types Deviation - Procedural Clearance Inflight Event / Encounter CFTT / CFIT

Narrative:

Aircraft X inbound from northeast. I descended him down a few times to lower altitudes to avoid opposite direction aircraft. The MVA in the area is 7100 feet. I was busy with other aircraft and was sequencing to final. I then issued an altitude of 6000 feet to aircraft X and he read it back. I usually issue 8000 feet for the north downwind. I got busy with other aircraft and finally noticed aircraft X descending out of 7100 feet in the 7100 foot MVA. I told aircraft X to maintain 7100 feet but he descended below that altitude saying he was assigned 6000 feet then climbed back up. I reviewed the recording and I did assign him an altitude below the minimum vectoring altitude (MVA) without even thinking about it.I've been totally sleep deprived outside of work. I didn't even know I assigned 6000 feet to aircraft X until I reviewed it on the replay! That's not good.

Original NASA ASRS Text

Title: BOI TRACON Controller descended an aircraft to an altitude below the MVA.

Narrative: Aircraft X inbound from northeast. I descended him down a few times to lower altitudes to avoid opposite direction aircraft. The MVA in the area is 7100 feet. I was busy with other aircraft and was sequencing to final. I then issued an altitude of 6000 feet to Aircraft X and he read it back. I usually issue 8000 feet for the north downwind. I got busy with other aircraft and finally noticed Aircraft X descending out of 7100 feet in the 7100 foot MVA. I told Aircraft X to maintain 7100 feet but he descended below that altitude saying he was assigned 6000 feet then climbed back up. I reviewed the recording and I did assign him an altitude below the minimum vectoring altitude (MVA) without even thinking about it.I've been totally sleep deprived outside of work. I didn't even know I assigned 6000 feet to Aircraft X until I reviewed it on the replay! That's not good.

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.