Diamond DA 40 N326AF

Summary

On 8 December 2010 at about 20:10 local time, a Diamond DA 40 registered N326AF, operated by Doss Aviation Inc, was involved in an incident near Colorado Springs, Colorado, United States. 2 people were on board and nobody was injured. The aircraft was slightly damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

8 December 2010 at 20:10

Classification

Incident

Location

Colorado Springs, Colorado, United States

Nearest airport

USAF Academy Airfield (AFF)

Coordinates

38.9697, -104.8128

Aircraft

Diamond DA 40

Registration

N326AF

Category

Airplane

Engines

1

Operator

Doss Aviation Inc

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Colorado Springs → Colorado Springs

Aircraft damage

Minor

Weather

VMC

Light

Day

NTSB number

CEN11IA114

Nobody was injured.

Fatigue failure of the nose wheel fork, which resulted in separation of the nose wheel.

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

Read the full NTSB narrative

The flight instructor and student pilot were performing their fourth touch-and-go landing of the day when the student pilot bounced the airplane. The instructor determined that the bounce was not severe and allowed the student to remain on the controls for a second touchdown. As the airplane contacted the runway, the instructor observed the airplane’s nose wheel depart the airplane. The airplane skidded down the runway for about 120 feet on its main landing gear and nose wheel strut before coming to a stop. An examination of the nose landing gear determined that multiple fatigue cracks had originated in the forward machined pockets of the left and right sides of the nose wheel fork. The cracks propagated until the fork could no longer sustain the applied operational loads, at which point overload failure occurred. As a result of the investigation, the airplane manufacturer developed a reinforced nose wheel fork, and the operator conducted a one-time inspection of its fleet of airplanes to identify any other nose wheel forks with fatigue cracks. The operator also implemented a method to nondestructively inspect all their airplanes’ nose wheel forks for fatigue cracks on a periodic basis. Additionally, the operator evaluated and implemented ways to decrease low cycle, high intensity stress brought on by nose wheel shimmy during takeoffs and landings and published guidance outlining specific steps to take in the event of hard landings, bounces, nose wheel strikes, and excessive nose wheel shimmy or vibration.

Quoted verbatim from the NTSB record.