Sanford ZENITH CH 601XL N9601

Summary

On 25 July 2015 at about 16:17 local time, a Sanford ZENITH CH 601XL registered N9601 was involved in an accident near Bristol, Wisconsin, United States. 2 people were on board and 2 died. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

25 July 2015 at 16:17

Classification

Accident

Location

Bristol, Wisconsin, United States

Nearest airport

Binzel (WI95)

Coordinates

42.5814, -88.0117

Aircraft

Sanford ZENITH CH 601XL

Registration

N9601

Category

Airplane

Year built

2008

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Valparaiso → Oshkosh

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN15FA315

2 people died.

The pilot’s failure to maintain airspeed and airplane control following a loss of engine power during cruise flight. Contributing to the accident was the installation of ignition system coils that were not engine-manufacturer replacement parts, which subsequently failed and resulted in the loss of engine power.

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

Read the full NTSB narrative

The pilot was flying his experimental, amateur-built airplane on a cross-country flight. GPS and radar data showed that, about an hour into the flight, the airplane turned left and then turned right. About 1 minute later, the airplane's groundspeed slowed to below its stall speed, and the airplane then entered a steep descent. Witnesses reported seeing the airplane "corkscrew" downward, and one witness reported that the propeller was "not spinning." Flight control continuity was confirmed, and witness marks on the propeller blades were consistent with the propeller not rotating at impact. A pilot who shared a hangar with the accident pilot reported that the accident pilot replaced the airplane's ignition system coils the day before the flight. Postaccident examination of the engine revealed that the coils were not engine-manufacturer replacement parts. During a postaccident test run, the engine would not start. During subsequent troubleshooting, the right distributor center coil tower socket was found separated; further examination revealed that it failed due to overload. The right ignition coil was then connected to the left distributor cap, and the engine operated normally during the subsequent test run. The broken right distributor cap was then replaced with a new cap, the right ignition coil was connected to the new cap, and the engine again operated normally during a subsequent test run. The left ignition coil did not produce any sparks during the test runs. No other anomalies were observed during the engine runs that would have prevented normal operation. The airplane likely experienced a loss of engine power due to the ignition issues, and the pilot failed to maintain adequate airspeed, which resulted in a subsequent stall and loss of airplane control.

Quoted verbatim from the NTSB record.