Narrative:

While in holding pattern over lawton VOR at 4000 ft with instrument student under hood, efc 5 mins away. Several MTR's shooting ILS approachs, cowl inspection door flew open causing loud popping noise. Noise ceased with power reduced to 1400 RPM. Declared emergency for immediate landing clearance. Landed uneventfully, repaired cowling door and continued instrument training.

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Original NASA ASRS Text

Title: INSTRUCTOR WITH STUDENT IN HOLDING PATTERN HAS COWL INSPECTION DOOR POP OPEN. DECLARED EMER. LANDS.

Narrative: WHILE IN HOLDING PATTERN OVER LAWTON VOR AT 4000 FT WITH INST STUDENT UNDER HOOD, EFC 5 MINS AWAY. SEVERAL MTR'S SHOOTING ILS APCHS, COWL INSPECTION DOOR FLEW OPEN CAUSING LOUD POPPING NOISE. NOISE CEASED WITH PWR REDUCED TO 1400 RPM. DECLARED EMER FOR IMMEDIATE LNDG CLRNC. LANDED UNEVENTFULLY, REPAIRED COWLING DOOR AND CONTINUED INST TRAINING.

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.