# NTSB DEN99LA124: Piper PA-18-150, N400MA, Lamar, CO, July 20, 1999

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 20, 1999, 15:30 local (21:30 UTC)
- Place: Lamar, CO
- Coordinates: 38.080024, -102.610176 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.0800&lon=-102.6102&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report October 13, 2000
- Report: Approved by Office Director
- NTSB case key (mKey): 46826
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN99LA124
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/46826/pdf
- Page: https://openairdocs.org/ntsb/DEN99LA124

## Probable cause

The left brake locked during takeoff roll for undetermined reasons.

## Sequence of events

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

- Nose over, takeoff - aborted
  - landing gear,normal brake system - locked (cause)
  - landing gear,normal brake system - undetermined (cause)
  - reason for occurrence undetermined

## Analysis

During takeoff roll on a test flight following maintenance in which the aircraft was not flown for an extended period of time, the left brake locked and the pilot aborted the takeoff.  During the abort, the aircraft nosed over.  The cause of the brake locking could not be determined.

## Factual narrative

On July 20, 1999, at 1530 mountain daylight time, a Piper PA-18-150, N400MA, sustained substantial damage when it nosed over during an aborted takeoff from a private airstrip approximately 5 miles north of Lamar, Colorado.  The commercial pilot/flight instructor/aircraft mechanic and sole occupant, was not injured.  Visual meteorological conditions prevailed for this local area test flight operating under Title 14 CFR Part 91 and no flight plan was filed.

According to the pilot, the flight was the first flight following replacement of the wing, and the aircraft had not flown in a (unspecified) "long time."  In an interview, the pilot said the left brake locked during the takeoff roll and he initiated an abort.  During this event, the aircraft nosed over and came to rest on its back damaging the lower cowl, spinner, propeller, windshield, left wing spar, right wing spar, both lift struts, and the rudder.

Due to damage incurred during the accident event, no determination could be made as to the cause of the brake problem.

## Aircraft

- Registration: [N400MA](https://openairdocs.org/aircraft/N400MA), registered now, S/N 18-7809126, built 1978 (OpenAirDocs)
- Reported make and model: Piper PA-18-150
- Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 18-7809126
- Airframe hours: 2128
- Engines: Lycoming O-320 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 91
- Registered owner: Allen H. Tinnes
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, July 20, 1999, 1 hours before
- Airport: (Private-No Name), runway 8, 4,600 × 60 ft, dirt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 53; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 10,000 total, 600 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 280° at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 88 °F, dew point 61 °F
- Altimeter: 30.00 inHg
- Observed at: LAA, 5 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 19990720009399A](https://openairdocs.org/incident/19990720009399A), Jul 20, 1999: Piper PA18150, Lamar, CO, Substantial damage. On takeoff, aircraft had brake problems. In an attempt to abort tkof, acft flipped over. (-23)pilot who is also a/c mechanic had just replaced the right wing…

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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