Beechcraft S35 N193Q

Summary

On 25 September 2015 at about 17:26 local time, a Beechcraft S35 registered N193Q, operated by Bennett Robert D, was involved in an accident near Pagosa Springs, Colorado, United States. 2 people were on board and 2 died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

25 September 2015 at 17:26

Classification

Accident

Location

Pagosa Springs, Colorado, United States

Coordinates

37.1100, -106.5700

Aircraft

Beechcraft S35

Registration

N193Q

Category

Airplane

Year built

1964

Engines

1

Operator

Bennett Robert D

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Durango → Pagosa Springs

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

CEN15FA424

2 people died.

Improper engine assembly by unknown maintenance personnel, which resulted in the failure of the No. 6 connecting rod due to oil starvation from the shifting of the crankshaft's No. 4 main bearing.

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

Read the full NTSB narrative

On the day before an air race competition, the accident pilot and another pilot decided to execute a practice circuit of the race course in their airplanes. As the two airplanes entered the course, the accident airplane was behind the other airplane. After they passed the first course waypoint, the accident pilot radioed the other pilot and stated that his airplane's engine had lost power and that the airplane was going down. No further communications were heard from the accident airplane. Witnesses observed white smoke coming from the underside of the airplane before they lost sight of it. Examination of the accident site indicated that the pilot was attempting to land on a gravel road when the airplane impacted a steel pole adjacent to the road and traveled about 200 yards before coming to rest inverted. Examination of the engine showed that the No. 6 connecting rod failed due to oil starvation. The oil starvation resulted from movement of the No. 4 main crankshaft bearing to a position where it blocked the oil transfer passage to the No. 6 connecting rod. The engine thru-bolts were improperly torqued by unknown maintenance personnel, and this allowed the No. 4 main bearing movement to occur. In addition, disassembly of the engine revealed that unapproved pistons had been installed. However, the unapproved pistons were not related to the engine failure.

Quoted verbatim from the NTSB record.