Narrative:

Initial problem was left oil pressure gauge went to 0. Performed the prescribed procedure. Contacted dispatch and maintenance control and decided to continue to okc. Checked circuit breakers for gauge as prescribed in the procedure. During approach check (16000-12000 ft) noted left hydraulic pressure gauge read 1500 psi vs expected 3000 psi. Performed 'book' procedure and checked those circuit breakers. By this time, we were 30-40 mi from destination and decided we had a potentially deteriorating airplane and we should not consider returning to mem (point of departure where maintenance from company is available). (First officer is flying at this point). When flaps and slats were selected, the left flap indicator stayed at 0 and first officer stated he could feel the adverse roll. Flaps were returned to 0 degrees. Book procedure was used for 'slats extended with no flap landing.' emergency was declared, cabin prepared, and we landed safely with no problems. Mechanic found the left instrument transformer circuit breaker popped. When reset, the 3 problem indicators worked properly. We missed that circuit breaker in our working the problems. We mentally connected the problems in that they were all from the left side. I believe we over-reacted to the 'normal' rolling motions that may be experienced as flaps are extended. We did not thoroughly check all circuit breakers, just the ones specific to the affected system. We assumed the aircraft was somehow deteriorating and, although we were thorough in procedures and landing prep, we didn't 'take a breather' and correctly link the problems and locate the source of trouble.

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Original NASA ASRS Text

Title: ACR MLG ACFT FLC MAD A NO FLAP EMER LNDG DUE TO AN ERRONEOUS READING FROM THE FLAP INDICATOR.

Narrative: INITIAL PROBLEM WAS L OIL PRESSURE GAUGE WENT TO 0. PERFORMED THE PRESCRIBED PROC. CONTACTED DISPATCH AND MAINT CTL AND DECIDED TO CONTINUE TO OKC. CHKED CIRCUIT BREAKERS FOR GAUGE AS PRESCRIBED IN THE PROC. DURING APCH CHK (16000-12000 FT) NOTED L HYD PRESSURE GAUGE READ 1500 PSI VS EXPECTED 3000 PSI. PERFORMED 'BOOK' PROC AND CHKED THOSE CIRCUIT BREAKERS. BY THIS TIME, WE WERE 30-40 MI FROM DEST AND DECIDED WE HAD A POTENTIALLY DETERIORATING AIRPLANE AND WE SHOULD NOT CONSIDER RETURNING TO MEM (POINT OF DEP WHERE MAINT FROM COMPANY IS AVAILABLE). (FO IS FLYING AT THIS POINT). WHEN FLAPS AND SLATS WERE SELECTED, THE L FLAP INDICATOR STAYED AT 0 AND FO STATED HE COULD FEEL THE ADVERSE ROLL. FLAPS WERE RETURNED TO 0 DEGS. BOOK PROC WAS USED FOR 'SLATS EXTENDED WITH NO FLAP LNDG.' EMER WAS DECLARED, CABIN PREPARED, AND WE LANDED SAFELY WITH NO PROBLEMS. MECH FOUND THE L INST TRANSFORMER CIRCUIT BREAKER POPPED. WHEN RESET, THE 3 PROBLEM INDICATORS WORKED PROPERLY. WE MISSED THAT CIRCUIT BREAKER IN OUR WORKING THE PROBLEMS. WE MENTALLY CONNECTED THE PROBLEMS IN THAT THEY WERE ALL FROM THE L SIDE. I BELIEVE WE OVER-REACTED TO THE 'NORMAL' ROLLING MOTIONS THAT MAY BE EXPERIENCED AS FLAPS ARE EXTENDED. WE DID NOT THOROUGHLY CHK ALL CIRCUIT BREAKERS, JUST THE ONES SPECIFIC TO THE AFFECTED SYS. WE ASSUMED THE ACFT WAS SOMEHOW DETERIORATING AND, ALTHOUGH WE WERE THOROUGH IN PROCS AND LNDG PREP, WE DIDN'T 'TAKE A BREATHER' AND CORRECTLY LINK THE PROBLEMS AND LOCATE THE SOURCE OF TROUBLE.

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.