20040426009029A

Accident · Substantial damage

FAA accident report · Hiller UH-12E · Haines, OR · April 26, 2004

Date: April 26, 2004 · 16:00 local
Place: Haines, OR
Phase of flight: Approach
Operating rules: Agricultural (Part 137)
Operator: SD7G
Damage: Substantial damage
Aircraft: N9785C
NTSB investigation: NTSBSEA04LA073
Reported as: Hiller UH12E
Reported engine: Allison 250C20
Fatal injuries: 0
Pilot’s flight hours: 5,000 total4,000 in this make and model50 in the last 90 days

N9785CRegistered now · Hiller UH-12ES/N 2269 Airframe modelHiller UH-12E Engine modelLycoming VO-540 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.

(-23) While returning to his main base following an aerial application job, at approximately 100 feet or less AGL the pilot heard a loud bang in the helicopter and loss of power. He immediately executed an emergency landing whereupon the left skid tube assembly collapsed, shearing at its fore and aft cross-tube attachment point causing the aircraft to come to rest on the left spray system saddle tank. The lower surface and outer tip of the main rotor blades area damaged from, what appears to be as, contact with the tail boom. The aft portion of the tail boom and tail rotor drive shaft is severed just forward of the tail rotor assembly. The (soloy) lower gearbox, isolation support linkage, came loose allowing the transmission and main rotor assembly to lean in an aft-ward position. The pilot reported the engine to spool-up, again during the crash.

As the FAA filed it

(-23) WHILE RETURNING TO HIS MAIN BASE FOLLOWING AN AERIAL APPLICATION JOB, AT APPROXIMATELY 100 FEET OR LESS AGL THE PILOT HEARD A LOUD BANG IN THE HELICOPTER AND LOSS OF POWER. HE IMMEDIATELY EXECUTED AN EMERGENCY LANDING WHEREUPON THE LEFT SKID TUBE ASSEMBLY COLLAPSED, SHEARING AT ITS FORE AND AFT CROSS-TUBE ATTACHMENT POINT CAUSING THE AIRCRAFT TO COME TO REST ON THE LEFT SPRAY SYSTEM SADDLE TANK. THE LOWER SURFACE AND OUTER TIP OF THE MAIN ROTOR BLADES AREA DAMAGED FROM, WHAT APPEARS TO BE AS, CONTACT WITH THE TAIL BOOM. THE AFT PORTION OF THE TAIL BOOM AND TAIL ROTOR DRIVE SHAFT IS SEVERED JUST FORWARD OF THE TAIL ROTOR ASSEMBLY. THE (SOLOY) LOWER GEARBOX, ISOLATION SUPPORT LINKAGE, CAME LOOSE ALLOWING THE TRANSMISSION AND MAIN ROTOR ASSEMBLY TO LEAN IN AN AFT-WARD POSITION. THE PILOT REPORTED THE ENGINE TO SPOOL-UP, AGAIN DURING THE CRASH.

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 SEA04LA073Accident · Minor injuriesLimited investigationFinal reportHaines, ORA momentary partial loss of power for undetermined reason(s) and the pilot's failure to maintain adequate RPM during his autorotation landing.Apr 26, 2004 · Substantial damage

Other reports on N9785C · 2

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

Accident 19930822030059APwr Off Vert Land/Autorotate · Auburn, WAThrough a connecting rod on takeoff. Autorotated into heavy brush. Severed tail rotor.Aug 22, 1993 · Substantial damage Accident 19760514015839ALow Level Operations · Tillamook, ORSpraying,lost RPM while maneuvering arnd tall tree,settled,struck t/r,entered spin,rolled dn hill.May 14, 1976 · Substantial damage