Beechcraft C90A N871KS

Summary

On 22 September 2007 at about 05:15 local time, a Beechcraft C90A registered N871KS was involved in an incident near Emporia, Kansas, United States. 8 people were on board and nobody was injured. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

22 September 2007 at 05:15

Classification

Incident

Location

Emporia, Kansas, United States

Coordinates

38.3319, -96.1911

Aircraft

Beechcraft C90A

Registration

N871KS

Category

Airplane

Engines

2

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Business

Phase of flight

Not recorded

Route

Tulsa → Manhattan

Aircraft damage

Not recorded

Weather

VMC

Light

Night

NTSB number

DEN08IA030

Nobody was injured.

The improper installation of the right elevator trim tab attachment hardware by maintenance personnel which resulted in excessive wear, fatigue, and the failure of the push-pull tube.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

While in cruise flight at 12,000 feet mean sea level, the airplane suddenly began "shuddering with a severe high frequency vibration." The pilot stated that the "vibration was in the entire airframe, not specifically the flight controls, so I had no clue where it was coming from." The pilot reduced the power on the left engine; however, the vibration continued. The pilot reduced the power on the right engine, and the vibration stopped. The pilot then shutdown and secured the right engine. Within a couple minutes of securing the right engine, the vibration "returned just as bad as before." The pilot then elected to divert to a nearby airport. The pilot lowered the landing gear during the approach, and the vibration stopped again. The airplane landed uneventfully. During a post flight inspection, the pilot observed the right elevator trim tab push rod was broken. The clevis which connected to the trim tab surface was "pinched due to an overtorqued bolt and nut." Metallurgical examination of the broken rod revealed a fatigue crack that propagated through at least 95 percent of the thread cross section. Maintenance records revealed the right elevator trim tab push-pull tube bolts and bushings were removed and replaced. At the time of the incident, the airframe had accumulated 101.5 flight hours since the inspection, and no additional maintenance to the right elevator trim system was noted in the maintenance records.

Quoted verbatim from the NTSB record.