Captain of an medium large transport descended below a safe altitude while making a visual circle to...

Attributes
ACN	301675
Time
Date	199504
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : geg
State Reference	WA
Altitude	agl bound lower : 700 agl bound upper : 700
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tower : geg
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 150 flight time total : 8000 flight time type : 2000
ASRS Report	301675
Person 2
Affiliation	company : air carrier
Function	flight crew : captain
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance non adherence other other anomaly other other spatial deviation
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : became reoriented flight crew : returned to intended course or assigned course flight crew : exited adverse environment
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

It was night. We were on a left downwind at spokane at 5000 ft MSL and were cleared for a visual approach for runway 21. We were requested to turn base quickly as possible because of traffic inbound straight in. As we were descending downwind I noticed that we were getting rather low and I was expecting the captain to turn base for our short approach. I glanced at the radio altimeter and saw we were at 900 ft AGL descending. Before I said anything the captain realized he was too low for our position on downwind. He leveled off (at approximately 700 AGL) and began a slow climb and turned base leg. After we landed uneventfully, we talked about what happened and he said he had set 2000 ft in the altitude alerter (I had just noticed this) for the visual approach. The field elevation is 2372 ft MSL. In his mind he had planned descending to 2000 ft MSL even though when we had briefed to approach he had briefed the airport elevation and MSA from the approach chart. I think the situation was compounded because he was not watching the airport off on his left side and letting the autoplt descend. I could have been more questioning on his short approach technique. I also missed noting what he selected on the altitude alerter which would have raised questions on his intentions.

Original NASA ASRS Text

Title: CAPT OF AN MLG DSNDED BELOW A SAFE ALT WHILE MAKING A VISUAL CIRCLE TO LAND APCH DUE TO A MIS-SET ALTIMETER ALERTER.

Narrative: IT WAS NIGHT. WE WERE ON A L DOWNWIND AT SPOKANE AT 5000 FT MSL AND WERE CLRED FOR A VISUAL APCH FOR RWY 21. WE WERE REQUESTED TO TURN BASE QUICKLY AS POSSIBLE BECAUSE OF TFC INBOUND STRAIGHT IN. AS WE WERE DSNDING DOWNWIND I NOTICED THAT WE WERE GETTING RATHER LOW AND I WAS EXPECTING THE CAPT TO TURN BASE FOR OUR SHORT APCH. I GLANCED AT THE RADIO ALTIMETER AND SAW WE WERE AT 900 FT AGL DSNDING. BEFORE I SAID ANYTHING THE CAPT REALIZED HE WAS TOO LOW FOR OUR POS ON DOWNWIND. HE LEVELED OFF (AT APPROX 700 AGL) AND BEGAN A SLOW CLB AND TURNED BASE LEG. AFTER WE LANDED UNEVENTFULLY, WE TALKED ABOUT WHAT HAPPENED AND HE SAID HE HAD SET 2000 FT IN THE ALT ALERTER (I HAD JUST NOTICED THIS) FOR THE VISUAL APCH. THE FIELD ELEVATION IS 2372 FT MSL. IN HIS MIND HE HAD PLANNED DSNDING TO 2000 FT MSL EVEN THOUGH WHEN WE HAD BRIEFED TO APCH HE HAD BRIEFED THE ARPT ELEVATION AND MSA FROM THE APCH CHART. I THINK THE SIT WAS COMPOUNDED BECAUSE HE WAS NOT WATCHING THE ARPT OFF ON HIS L SIDE AND LETTING THE AUTOPLT DSND. I COULD HAVE BEEN MORE QUESTIONING ON HIS SHORT APCH TECHNIQUE. I ALSO MISSED NOTING WHAT HE SELECTED ON THE ALT ALERTER WHICH WOULD HAVE RAISED QUESTIONS ON HIS INTENTIONS.

Data retrieved from NASA's ASRS site as of July 2007 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.

Captain of an medium large transport descended below a safe altitude while making a visual circle to land approach due to a mis-set altimeter alerter.