Flight crew of a B737-200 got a false GS during an ILS approach resulting in making a missed approach and then subsequent visual approach upon breaking out of the overcast. Reporter stated that they were turned over late and cleared for the approach by center causing them to intercept the GS high.

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Attributes
ACN	415091
Time
Date	199809
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : bet airport : bet
State Reference	AK
Altitude	msl bound lower : 1200 msl bound upper : 1500
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zan tower : bet
Operator	common carrier : air carrier
Make Model Name	B737-200
Operating Under FAR Part	Part 121
Flight Phase	descent : approach landing : missed approach
Route In Use	approach : visual arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 5000 flight time type : 3000
ASRS Report	415091
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 110 flight time total : 12000 flight time type : 9000
ASRS Report	415277
Events
Anomaly	non adherence : published procedure other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	other other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Operational Deviation other

Narrative:

Captured unreliable false high GS during ILS approach at bethel. Leveled off at 1200 ft MSL and proceeded to missed approach point. Broke out in visual conditions. Tower directed us to join left traffic behind 3 light aircraft. Landed uneventfully on runway 18 at pabe. Had very late handoff from zan which compounded communication with bet tower. Callback conversation with reporter revealed the following information: reporter stated that he and the captain thought that they received the erroneous GS indication since they intercepted the GS too high because of a late handoff. This was verified by another crew that landed after them who stated that the GS was normal. Subsequent ILS approach also confirmed that their aircraft GS worked satisfactorily and the bet airport GS worked just fine on the next flight in. The reporter was flying a B737-200.

Original NASA ASRS Text

Title: FLC OF A B737-200 GOT A FALSE GS DURING AN ILS APCH RESULTING IN MAKING A MISSED APCH AND THEN SUBSEQUENT VISUAL APCH UPON BREAKING OUT OF THE OVCST. RPTR STATED THAT THEY WERE TURNED OVER LATE AND CLRED FOR THE APCH BY CTR CAUSING THEM TO INTERCEPT THE GS HIGH.

Narrative: CAPTURED UNRELIABLE FALSE HIGH GS DURING ILS APCH AT BETHEL. LEVELED OFF AT 1200 FT MSL AND PROCEEDED TO MISSED APCH POINT. BROKE OUT IN VISUAL CONDITIONS. TWR DIRECTED US TO JOIN L TFC BEHIND 3 LIGHT ACFT. LANDED UNEVENTFULLY ON RWY 18 AT PABE. HAD VERY LATE HDOF FROM ZAN WHICH COMPOUNDED COM WITH BET TWR. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT HE AND THE CAPT THOUGHT THAT THEY RECEIVED THE ERRONEOUS GS INDICATION SINCE THEY INTERCEPTED THE GS TOO HIGH BECAUSE OF A LATE HDOF. THIS WAS VERIFIED BY ANOTHER CREW THAT LANDED AFTER THEM WHO STATED THAT THE GS WAS NORMAL. SUBSEQUENT ILS APCH ALSO CONFIRMED THAT THEIR ACFT GS WORKED SATISFACTORILY AND THE BET ARPT GS WORKED JUST FINE ON THE NEXT FLT IN. THE RPTR WAS FLYING A B737-200.

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.