OpenAirDocs.org

19980311003149A

Accident · Substantial damage
Open the Markdown

FAA accident report · Bell 47D1 · Jeanerette, LA · March 11, 1998

FAA Aviation Safety Information Portal

© OpenStreetMap
Date
March 11, 1998 · 16:00 local
Place
Jeanerette, LA
Phase of flight
Sfl Autorotation
Operating rules
General operating rules (Part 91)
Damage
Substantial damage
Aircraft
N13012
NTSB investigation
NTSBFTW98LA144
Reported as
Bell 47D1
Reported engine
Lycoming VO435A1B
Fatal injuries
0
Pilot’s flight hours
2,753 total335 in this make and model176 in the last 90 days
N13012Registration cancelled Feb 8, 2018 · Bell 47D1S/N 648 · Built 1953Airframe modelBell 47D1Engine modelFranklin 6V4 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.

Heli was practicing approaches when it started to vibrate vertically and laterally, landed hard. Jeanerette, LA (-23) on March 12, 1998, it was reported that there had been an accident which involved a Bell 47-D1 aircraft. After further investigation, it was stated by the pilot of the aircraft that during flight training at an altitude of 300 feet above ground level, the aircraft experienced severe vibrations, (lateral and vertical). The instructor pilot assumed control of the aircraft, lowered collective. The aircraft then hit the ground sideways at 20 degrees right and rolled several times. He had tried to flare at approximately 10 feet but could not control cyclic stick. I arrived on the scene at 4:00 pm, March 12, 1998, to find the helicopter lying on it's left side in a sugar cane field. The tailboom was torn off and lying within 3 feet of the fuselage. One main rotor blade was 200 feet from the wreckage. There was only one drive link on the aircraft swashplate; the other was never found. (.4)the dual student pilot was practicing landings in the local practice area, and had completed 4 to 5 landings. On the next landing, they were heading west, level at 350 feet AGL, with an airspeed of 35 mph. As the student lowered the collective to initiate a steep approach, a severe vertical vibration was encountered. About 2 to 3 seconds later, a severe lateral vibration began. The flight instructor took the controls and continued the descent towards the landing area. At about 10 feet the instructor tried to reduce forward airspeed and descent rate by moving the cyclic aft and raising the collective. 'Neither of those inputs seemed to help a lot and we impacted hard.' The helicopter rolled over to the left before coming to rest heading to the east. There were no reported problems with tail rotor control. Examination of the helicopter by the FAA inspector revealed that the scissor hinge bolt which attaches the scissor to the swash plate was missing. He added that according to the maintenance records, the 5, 258 helicopter, underwent a 100 hour inspection on February 15, 1998, approximately 20 hours prior to the accident.

As the FAA filed it

HELI WAS PRACTICING APPROACHES WHEN IT STARTED TO VIBRATE VERTICALLY AND LATERALLY, LANDED HARD. JEANERETTE, LA (-23) ON MARCH 12, 1998, IT WAS REPORTED THAT THERE HAD BEEN AN ACCIDENT WHICH INVOLVED A BELL 47-D1 AIRCRAFT. AFTER FURTHER INVESTIGATION, IT WAS STATED BY THE PILOT OF THE AIRCRAFT THAT DURING FLIGHT TRAINING AT AN ALTITUDE OF 300 FEET ABOVE GROUND LEVEL, THE AIRCRAFT EXPERIENCED SEVERE VIBRATIONS, (LATERAL AND VERTICAL). THE INSTRUCTOR PILOT ASSUMED CONTROL OF THE AIRCRAFT, LOWERED COLLECTIVE. THE AIRCRAFT THEN HIT THE GROUND SIDEWAYS AT 20 DEGREES RIGHT AND ROLLED SEVERAL TIMES. HE HAD TRIED TO FLARE AT APPROXIMATELY 10 FEET BUT COULD NOT CONTROL CYCLIC STICK. I ARRIVED ON THE SCENE AT 4:00 PM, MARCH 12, 1998, TO FIND THE HELICOPTER LYING ON IT'S LEFT SIDE IN A SUGAR CANE FIELD. THE TAILBOOM WAS TORN OFF AND LYING WITHIN 3 FEET OF THE FUSELAGE. ONE MAIN ROTOR BLADE WAS 200 FEET FROM THE WRECKAGE. THERE WAS ONLY ONE DRIVE LINK ON THE AIRCRAFT SWASHPLATE; THE OTHER WAS NEVER FOUND. (.4)THE DUAL STUDENT PILOT WAS PRACTICING LANDINGS IN THE LOCAL PRACTICE AREA, AND HAD COMPLETED 4 TO 5 LANDINGS. ON THE NEXT LANDING, THEY WERE HEADING WEST, LEVEL AT 350 FEET AGL, WITH AN AIRSPEED OF 35 MPH. AS THE STUDENT LOWERED THE COLLECTIVE TO INITIATE A STEEP APPROACH, A SEVERE VERTICAL VIBRATION WAS ENCOUNTERED. ABOUT 2 TO 3 SECONDS LATER, A SEVERE LATERAL VIBRATION BEGAN. THE FLIGHT INSTRUCTOR TOOK THE CONTROLS AND CONTINUED THE DESCENT TOWARDS THE LANDING AREA. AT ABOUT 10 FEET THE INSTRUCTOR TRIED TO REDUCE FORWARD AIRSPEED AND DESCENT RATE BY MOVING THE CYCLIC AFT AND RAISING THE COLLECTIVE. 'NEITHER OF THOSE INPUTS SEEMED TO HELP A LOT AND WE IMPACTED HARD.' THE HELICOPTER ROLLED OVER TO THE LEFT BEFORE COMING TO REST HEADING TO THE EAST. THERE WERE NO REPORTED PROBLEMS WITH TAIL ROTOR CONTROL. EXAMINATION OF THE HELICOPTER BY THE FAA INSPECTOR REVEALED THAT THE SCISSOR HINGE BOLT WHICH ATTACHES THE SCISSOR TO THE SWASH PLATE WAS MISSING. HE ADDED THAT ACCORDING TO THE MAINTENANCE RECORDS, THE 5, 258 HELICOPTER, UNDERWENT A 100 HOUR INSPECTION ON FEBRUARY 15, 1998, APPROXIMATELY 20 HOURS PRIOR TO THE ACCIDENT.

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 FTW98LA144Accident · Minor injuriesLimited investigationFinal reportJeanerette, LAThe in-flight disconnect of the rotating scissors due to the separation of its hinge bolt.Mar 11, 1998 · Substantial damage

Other reports on N13012 · 2

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

Accident 19840505017089APwr Off Run Land (Autorotation · Ridge Farm, ILLost engine and rotor RPM after takeoff. Made a hard autorotation landing and rolled over. No engine defects found.May 5, 1984 · Substantial damageAccident 19740706017979AFcd/Prec Ldg From Cruise · Almyra, ARSpray pmp injestd stone whch causd eng accssry drv gr to shearJul 6, 1974 · Substantial damage