C172 pilot during an instrument approach has a low altitude alert warning issued by the controller.

Attributes
ACN	695411
Time
Date	200604
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : fsd.airport
State Reference	SD
Altitude	msl single value : 3400
Environment
Flight Conditions	IMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : fsd.tracon
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Navigation In Use	ils localizer & glide slope : n/s
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 47 flight time total : 3000 flight time type : 47
ASRS Report	695411
Person 2
Affiliation	government : faa
Function	controller : approach
Events
Anomaly	aircraft equipment problem : less severe non adherence : published procedure other anomaly other spatial deviation other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued alert flight crew : returned to intended or assigned course flight crew : became reoriented
Supplementary
Problem Areas	Chart Or Publication Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

I was on an instrument approach to sioux falls; sd; after the first long IMC flight I have done in several yrs. My vertical card compass gave headings 30 degrees off; but the approach controller recognized the problem; and between the two of us we managed vectors onto the localizer. When I tried to stabilize my direction; the distraction caused me to set off the tower low altitude alert. The tower notified me and I corrected and continued the approach without further difficulty. A complicating factor was my use of govt charts; I usually use commercial charts. In the twilight I had trouble finding the minimum descent altitude even though it is clearly depicted. Lack of recent IFR experience coupled with a long; intense work day led to physical and mental fatigue which coupled with lack of recent IMC flying to produce this incident.

Original NASA ASRS Text

Title: C172 PLT DURING AN INST APCH HAS A LOW ALT ALERT WARNING ISSUED BY THE CTLR.

Narrative: I WAS ON AN INST APCH TO SIOUX FALLS; SD; AFTER THE FIRST LONG IMC FLT I HAVE DONE IN SEVERAL YRS. MY VERT CARD COMPASS GAVE HDGS 30 DEGS OFF; BUT THE APCH CTLR RECOGNIZED THE PROB; AND BTWN THE TWO OF US WE MANAGED VECTORS ONTO THE LOC. WHEN I TRIED TO STABILIZE MY DIRECTION; THE DISTR CAUSED ME TO SET OFF THE TWR LOW ALT ALERT. THE TWR NOTIFIED ME AND I CORRECTED AND CONTINUED THE APCH WITHOUT FURTHER DIFFICULTY. A COMPLICATING FACTOR WAS MY USE OF GOVT CHARTS; I USUALLY USE COMMERCIAL CHARTS. IN THE TWILIGHT I HAD TROUBLE FINDING THE MINIMUM DSCNT ALT EVEN THOUGH IT IS CLRLY DEPICTED. LACK OF RECENT IFR EXPERIENCE COUPLED WITH A LONG; INTENSE WORK DAY LED TO PHYSICAL AND MENTAL FATIGUE WHICH COUPLED WITH LACK OF RECENT IMC FLYING TO PRODUCE THIS INCIDENT.

Data retrieved from NASA's ASRS site as of January 2009 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.