A cessna 172P made an emergency landing due to what appeared to be abnormal engine noises.

Attributes
ACN	349222
Time
Date	199609
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : n90 airport : bdr
State Reference	NY
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : n90
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise other other other
Route In Use	approach : visual
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument pilot : commercial
Experience	flight time last 90 days : 17 flight time total : 530 flight time type : 200
ASRS Report	349222
Person 2
Affiliation	Other
Function	observation : passenger
Qualification	other other : other
Events
Anomaly	aircraft equipment problem : less severe other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa other other : unspecified cockpit
Resolutory Action	flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

In sum: reporter was flying 1 hour and 15 mins from ack wbound along the coast with flight following. 2 mi from bdr VOR reporter heard a clattering noise which sounded like a piston rod. All engine indications were in the green. In trying to diagnose the problem the airplane descended 400 ft. ZNY questioned the change in altitude. Once the reporter became aware of the altitude loss, the reporter panicked. 'Something is seriously wrong with the engine, why am I falling?' the reporter advised ATC they were experiencing technical problems and needed vectors to bdr. ATC replied, 'look directly below you.' bdr was contacted and the reporter landed on runway 24. The problem turned out to be a LORAN unit metal housing that had worked loose behind the instrument panel.

Original NASA ASRS Text

Title: A CESSNA 172P MADE AN EMER LNDG DUE TO WHAT APPEARED TO BE ABNORMAL ENG NOISES.

Narrative: IN SUM: RPTR WAS FLYING 1 HR AND 15 MINS FROM ACK WBOUND ALONG THE COAST WITH FLT FOLLOWING. 2 MI FROM BDR VOR RPTR HEARD A CLATTERING NOISE WHICH SOUNDED LIKE A PISTON ROD. ALL ENG INDICATIONS WERE IN THE GREEN. IN TRYING TO DIAGNOSE THE PROB THE AIRPLANE DSNDED 400 FT. ZNY QUESTIONED THE CHANGE IN ALT. ONCE THE RPTR BECAME AWARE OF THE ALT LOSS, THE RPTR PANICKED. 'SOMETHING IS SERIOUSLY WRONG WITH THE ENG, WHY AM I FALLING?' THE RPTR ADVISED ATC THEY WERE EXPERIENCING TECHNICAL PROBS AND NEEDED VECTORS TO BDR. ATC REPLIED, 'LOOK DIRECTLY BELOW YOU.' BDR WAS CONTACTED AND THE RPTR LANDED ON RWY 24. THE PROB TURNED OUT TO BE A LORAN UNIT METAL HOUSING THAT HAD WORKED LOOSE BEHIND THE INST PANEL.

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.