19980404005579A

Accident · Substantial damage

FAA accident report · Ayres S2R · Cushing, OK · April 4, 1998

Date: April 4, 1998 · 11:20 local
Place: Cushing, OK
Airport: Cushing Municipal Airport
Phase of flight: Forced/Precautionary Landing
Operating rules: General operating rules (Part 91)
Operator: SNZG
Damage: Substantial damage
Aircraft: N8984Q
NTSB investigation: NTSBFTW98LA171
Reported as: Ayres S2R
Reported engine: WRIGHT R182076B
People aboard: 1
Fatal injuries: 0
Pilot’s flight hours: 19,200 total1,600 in this make and model50 in the last 90 days

N8984QRegistered now · Aero Commander S2RS/N 1654R · Built 1972 Airframe modelAero Commander S2R Engine modelPratt & Whitney R1340 seriesReciprocating

From the FAA’s Accident/Incident Data System (AIDS), through its Aviation Safety Information Portal, as reported. The NTSB investigates accidents separately, and its record of an accident is the fuller one. The aircraft is matched to the registry by N-number and event date, checked against the reported make and model; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

What happened

The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.

(.4)During the initial takeoff/climb loss of manifold pressure was noted by the pilot. The engine backfired as the pilot increased the throttle and mixture and lost power. During the forced landing, the pilot maneuvered the airplane to avoid power lines and homes. The main gear collapsed as the airplane touched down hard in an open field. Examination revealed that the mixture control at the carburetor was set at less than 50 percent travel toward the rich stop on the carburetor. Engine continutiy was confirmed to the accessory case; however, neither magneto rotated when the propleer rotated. A mechanic stated that this lack of magneto ratation indicates that the accessor shaft has sheared inside the rear case of the engine. The carburetor and engine were not disassembled, there fore, it was not determined whether the damage to the mixture control and the drive shaft were preexisting or impact related. (-23) see narrative #FTW98LA171.

As the FAA filed it

(.4)DURING THE INITIAL TAKEOFF/CLIMB LOSS OF MANIFOLD PRESSURE WAS NOTED BY THE PILOT. THE ENGINE BACKFIRED AS THE PILOT INCREASED THE THROTTLE AND MIXTURE AND LOST POWER. DURING THE FORCED LANDING, THE PILOT MANEUVERED THE AIRPLANE TO AVOID POWER LINES AND HOMES. THE MAIN GEAR COLLAPSED AS THE AIRPLANE TOUCHED DOWN HARD IN AN OPEN FIELD. EXAMINATION REVEALED THAT THE MIXTURE CONTROL AT THE CARBURETOR WAS SET AT LESS THAN 50 PERCENT TRAVEL TOWARD THE RICH STOP ON THE CARBURETOR. ENGINE CONTINUTIY WAS CONFIRMED TO THE ACCESSORY CASE; HOWEVER, NEITHER MAGNETO ROTATED WHEN THE PROPLEER ROTATED. A MECHANIC STATED THAT THIS LACK OF MAGNETO RATATION INDICATES THAT THE ACCESSOR SHAFT HAS SHEARED INSIDE THE REAR CASE OF THE ENGINE. THE CARBURETOR AND ENGINE WERE NOT DISASSEMBLED, THERE FORE, IT WAS NOT DETERMINED WHETHER THE DAMAGE TO THE MIXTURE CONTROL AND THE DRIVE SHAFT WERE PREEXISTING OR IMPACT RELATED. (-23) SEE NARRATIVE #FTW98LA171.

NTSB investigation

The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.

NTSB FTW98LA171Accident · No injuriesLimited investigationFinal reportCushing, OKThe total loss of engine power resulting from a sheared accessory drive due to an undetermined reason. A factor was the lack of suitable terrain for the forced landing.Apr 4, 1998 · Substantial damage

Other reports on N8984Q · 1

Matched to the same aircraft by N-number and date.

Incident 19950217004659IFcd/Prec Ldg From Cruise · Cushing, OKNarrative: on February 17, 1995, at approximately 1445 local time, an aircraft, N8984, ayers S2R, was on a flight to dispense herbicide material with a full load. The aircraft was in level flight on the way to the field to be sprayed ten miles northeast of…Feb 17, 1995 · Minor damage