Embraer ERJ170 200LR N161SY

Summary

On 4 December 2016 at about 20:53 local time, a Embraer ERJ170 200LR registered N161SY, operated by Skywest Airlines Inc, was involved in an incident near San Antonio, Texas, United States. 59 people were on board and one had minor injuries. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

4 December 2016 at 20:53

Classification

Incident

Location

San Antonio, Texas, United States

Nearest airport

San Antonio Intl (SAT)

Coordinates

29.5314, -98.4683

Aircraft

Embraer ERJ170 200LR

Registration

N161SY

Category

Airplane

Year built

2016

Engines

2

Operator

Skywest Airlines Inc

Operating rule

Part 121: Air Carrier

Phase of flight

Not recorded

Route

Houston → Monterrey

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

ENG17IA005

1 person had minor injuries.

A failure of the nose landing gear down lock spring which precluded normal downlock operation of the nose landing gear.  The spring failure was due to the presence of too much retained austenite which led to the formation of progressive cracking and subsequent failure of the spring.

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

Read the full NTSB narrative

Based on the material laboratory examinations, the area around the failure point contained higher than allowable levels of retained austenite. The presence of too much retained austenite subsequently resulted in the formation of intergranular cracking. The intergranular cracking resulted in the formation of progressive cracking, which caused the separation and subsequent failure of the downlock spring. After the failure, the spring became lodged in the nose landing gear yoke, which prevented the nose gear from achieving a down and locked position. Without the NLG being fully down and locked, as the weight of the aircraft during landing was transferred to the nose and main landing gear, the NLG subsequently retracted back into the nose gear wheel.

Quoted verbatim from the NTSB record.