# NTSB NYC07LA227: Beech A23-24, N5073T, West Chester, PA, September 14, 2007

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: September 14, 2007, 10:49 local (14:49 UTC)
- Place: West Chester, PA
- Coordinates: 39.990276, -75.581947
- Nearby events: https://openairdocs.org/map.md?lat=39.9903&lon=-75.5819&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 1 minor
- Status: Completed, report May 28, 2008
- Report: Approved by Office Director
- Parties: FAA/FSDO
- ADs cited in the narratives: [AD 71-06-08](https://openairdocs.org/ad/71-06-08) (OpenAirDocs)
- NTSB case key (mKey): 66670
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC07LA227
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66670/pdf
- Page: https://openairdocs.org/ntsb/NYC07LA227

## Probable cause

The total failure of the left brake disc due to corrosion.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - on ground/water, landing
  - landing gear,normal brake system - corroded (cause)
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - berm

## Analysis

The airplane touched down more than halfway beyond the approach end of runway 9; a 3,347-foot-long, 50-foot-wide, asphalt runway. The pilot applied heavy braking, and the airplane veered off the right side of the runway. Examination of the wreckage revealed that the left brake disc had separated from its housing. The right brake disc had cracked, but remained attached to its housing. The left and right brake discs exhibited corrosion. The airplane's most recent annual inspection was completed about 4 months prior to the accident. The mechanic that performed the annual inspection stated that he did not observe corrosion on the brakes at that time. Airworthiness Directive (AD) 71-06-08 addressed repetitive brake disc inspections and replacements; however, the make and model brake disk on the accident airplane was not included on the AD. The reported weather at an airport near the accident site, about the time of the accident, included winds from 160 degrees at 8 knots, varying between 120 degrees and 200 degrees.

## Factual narrative

On September 14, 2007, at 1049 eastern daylight time, a Beech A23-24, N5073T, was substantially damaged while landing at Brandywine Airport (OQN), West Chester, Pennsylvania. The certificated private pilot sustained minor injuries, and the passenger was seriously injured. Visual meteorological conditions prevailed for the flight that departed Sussex County Airport (GED), Georgetown, Delaware, about 0930. No flight plan was filed for the local personal flight conducted under 14 Code of Federal Regulations Part 91.

The airplane landed on runway 9; a 3,347-foot-long, 50-foot-wide, asphalt runway. The pilot reported that the airplane touched down on centerline. He then retracted the flaps and checked the brakes. The pilot let the airplane roll out, and applied continuous braking near the last one-third of the runway. While braking, the left pedal "went away," and the airplane turned right. The airplane traveled off the right side of the runway, down a berm, and came to rest next to a building. The airplane sustained substantial damage to the firewall area, and all three landing gear had separated from the airframe.

The pilot reported a total flight experience of 1,260 hours; of which, 570 hours were in the same make and model as the accident airplane. He flew 6 hours during the 90 days preceding the accident. The pilot estimated the winds were from the east-southeast at 9 knots, gusting to 14 knots.

A Federal Aviation Administration (FAA) inspector stated that he interviewed a witness, who reported that the accident airplane had to go-around during the first landing attempt, as it was "high and fast."

The FAA inspector also viewed a surveillance video that captured the landing accident. The video revealed that the airplane touched down more than halfway down the runway, the pilot applied "heavy" braking, and the airplane veered off the right side of the runway.

The FAA inspector added that examination of the wreckage revealed that the left brake disk had separated from its housing. The right brake disc had cracked, but remained attached to its housing. The left and right brake discs exhibited corrosion. The airplane's most recent annual inspection was completed on May 24, 2007. The FAA inspector interviewed the mechanic that performed that inspection, who stated that he did not observe corrosion on the brakes at that time.

The FAA inspector further stated that airworthiness directive (AD) 71-06-08 addressed repetitive brake disc inspections and replacements; however, the make and model brake disk on the accident airplane was not included in the AD.

Review of the AD revealed a requirement to inspect the brake discs for cracks, or other obvious defects, using a 10-power glass or equivalent. If any defects were found, the brake discs needed to be replaced with a specified new model brake disc. In addition, the inspection needed to be repeated after every 50 hours of operation, or until the specified new brake discs were installed.

The inspector subsequently filed a malfunction or defect report (similar to a service difficulty report) to bring awareness to the situation and have the make and model brake disc added to the AD.

The reported weather at an airport located about 15 miles south of the accident site, at 1054, was: wind from 160 degrees at 8 knots, varying between 120 degrees and 200 degrees; visibility 10 miles; few clouds at 3,000 feet; broken ceiling at 4,900 feet; broken ceiling at 6,000 feet; temperature 22 degrees Celsius (C); dew point 16 degrees C; altimeter 30.14 inches of mercury.

## Aircraft

- Registration: [N5073T](https://openairdocs.org/deregistered/N5073T-2013-08-13), registration cancelled 2013-08-13, S/N MA-319, built 1968 (OpenAirDocs)
- Reported make and model: Beech A23-24
- Registry model: [Beech A23-24](https://openairdocs.org/model/beech-a23-24) (registry code 1151226) (OpenAirDocs)
- Registry engine: [Lycoming I0360 series](https://openairdocs.org/engine/lycoming-i0360-series) (registry code 41515, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: MA-319
- Airframe hours: 2300
- Engines: Lycoming IO-360 200 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Warren B Knowles
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 1, 2007, 8 hours before
- Departed: GED, Georgetown, DE
- Destination: OQN, West Chester, PA
- Airport: OQN, Brandywinde Airport, runway 9, 3,347 × 50 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 71; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review October 1, 2006; seat: left; flight hours: 1,260 total, 570 in this make and model, 1,040 as pilot in command, 6 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 160° at 8 knots
- Visibility: 10 statute miles
- Lowest ceiling: 4,900 ft broken
- Temperature: 72 °F, dew point 61 °F
- Altimeter: 30.13 inHg
- Observed at: PTW, 15 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 20070914829779A](https://openairdocs.org/incident/20070914829779A), Sep 14, 2007: Beech A2324, West Chester, PA, Substantial damage. (-23) Pilot performed an unsafe landing (long and fast) which required abnormally heavy braking in order to make the last taxiway at the end of the runway.…

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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