Schweizer G-164B N3633C

Summary

On 21 May 2010 at about 23:00 local time, a Schweizer G-164B registered N3633C, operated by Sunrise Dusters Inc, was involved in an accident near Robbins, California, United States. One person was on board and one was seriously injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

21 May 2010 at 23:00

Classification

Accident

Location

Robbins, California, United States

Nearest airport

Wagner Field (CA18)

Coordinates

38.8719, -121.7097

Aircraft

Schweizer G-164B

Registration

N3633C

Category

Airplane

Engines

1

Operator

Sunrise Dusters Inc

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Route

Robbins → Robbins

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR10LA253

1 person was seriously injured.

The failure of the wheel hub flange, which allowed the over size tire to expand and impinge on the brake disc and caliper, which resulted in a loss of control during the landing.

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

Read the full NTSB narrative

During an agricultural application flight, the pilot noticed that the right brake pedal was stiff and saw what appeared to be hydraulic fluid on his foot. The pilot tried without success to set and release the brake to correct the stiff brake pedal. He radioed his base of operations to notify ground personnel of the possible brake problem and of his intention to return to the airfield. The pilot attempted to land the tailwheel-equipped airplane with a direct crosswind that was 15 knots, gusting to 20 knots. As soon as the airplane’s right wheel touched down, the pilot felt the airplane start to pull to the right. When he tried to correct the airplane’s direction to the left, the pilot felt the wind shift and the airplane veered off the left side of the runway into an adjacent irrigation ditch. The left wing came to rest on the sloping terrain forming the ditch. The investigation showed that the right brake calipers separated from the airplane at touchdown. Examination of the right wheel revealed that the inner wheel hub flange sustained a circumferential failure that allowed the inflated tire and tube to expand and impinge upon the brake disc and caliper. The examination further showed that the tire installed on the airplane was a larger size than the standard tire size recommended by the manufacturer of the wheel assembly (29x11.0-10 instead of 8.50-10). Because of its larger-than-standard size, the tire impinged on the brake disc and caliper after the wheel hub flange failed, which resulted in the caliper’s separation upon touchdown. According to the type certificate holder for the airplane, some G-164B operators of the accident airplane model have obtained field approval from their local Federal Aviation Administration (FAA) flight standards district office to use the oversize tires. The FAA had issued such a field approval for the accident airplane. As a result of this accident and the subsequent investigation, on December 15, 2010, the FAA issued Special Airworthiness Information Bulletin CE-11-06, which reminded operators that oversized tire modifications require analysis and substantiation as well as periodic inspections to prevent unsafe conditions, none of which were accomplished in this case.

Quoted verbatim from the NTSB record.