Aviation safety investigations & reports

Piper Aircraft Corp PA-28-181, VH-UZR

Investigation number:
199802022
Status: Completed
Investigation completed

Summary

A Piper Archer and a Piper Tomahawk collided at an altitude of about 1,200 ft as the Archer was tracking to enter the crosswind leg for a landing on runway 34 at Hoxton Park aerodrome. The collision occurred in fine and clear conditions, about 0.5 NM east of the upwind end of the runway. Both aircraft were being flown under the visual flight rules (VFR). The pilot of the Archer was able to maintain control of his aircraft and make a successful approach and landing on runway 34, although the nose landing gear had been substantially damaged in the collision. The aircraft was stopped on the runway, resting on the collapsed nose landing gear.

The collision was observed by witnesses who reported that the Tomahawk immediately spiralled down and crashed into an unoccupied house in a suburban housing area. Both occupants were fatally injured. There was no fire and there were no injuries to persons on the ground.

Operations at Hoxton Park are not directed by air traffic control services and rely on pilots seeing and avoiding other aircraft. The aerodrome is located within a common traffic advisory frequency (CTAF) area, extending to a 2 NM radius from the aerodrome and to a height of 1,700 ft. Pilots of radio-equipped aircraft intending to operate within that area are required to make a radio broadcast when approaching the CTAF boundary. That broadcast must include aircraft callsign and type, position, level, and intentions. No other radio report is required prior to landing.

The pilot of the Archer reported that he had made a broadcast on the CTAF when 3 NM inbound to Hoxton Park. He then descended to 1,200 ft and tracked to join the crosswind leg for runway 34, making a "joining crosswind" broadcast while still approaching the upwind end of the runway. He saw another aircraft turning onto crosswind after taking off from runway 34, and a second aircraft on the downwind leg. At about that time, he saw to his left the underside of an aircraft turning to the left, about 50 m away, but skidding towards him at about the same altitude. The pilot of the Archer said he started to turn to the right to avoid a collision, but there was a bang just moments after he first saw the aircraft. He briefly glanced back and saw the aircraft spiralling down to the left. It appeared to him that the outboard end of the right wing of the other aircraft was bent upward at about 45 degrees and that the aircraft appeared to be totally out of control. As he was concerned for the safety of his own aircraft, he concentrated on landing as soon as possible. At no stage prior to the accident was he aware of the presence of the Tomahawk.

Investigation of the wreckage of the Tomahawk indicated that the engine had been torn out during the impact with the house. There was major disruption to the aircraft structure and cockpit area. Small sections from the right wing were scattered about the immediate neighbourhood. The cockpit instruments and controls were too severely damaged to provide any useful information. The very high frequency radio was selected to the CTAF frequency. There was no evidence of any pre-existing defects or abnormalities with either aircraft that may have contributed to the accident.

A metallurgical examination of a section of the right outboard wing from the Tomahawk revealed that a propeller blade of the Archer had first cut through the wing-tip plastic moulding near the trailing edge. The propeller had then cut through the wing at about the mid-chord area before finally striking the leading edge. The action of the propeller blades striking the wing resulted in disruption of the wing structure, with an associated upward bending of the outer section of the wing.

Analysis

The investigation was unable to determine the flight path of the Tomahawk after it had departed from Bankstown on a VFR flight to the training area and Hoxton Park earlier in the morning. The damage to the right wing of the Tomahawk, together with witness observations, indicated that the Archer had approached from the rear right quadrant of that aircraft. The location of the collision point, and the respective tracks of the two aircraft, make it likely that the Tomahawk had been flying parallel to runway 34 on the non-active side of the circuit and that it had commenced to, or was about to, turn left to join the crosswind leg.

The investigation was also unable to determine if the pilot of the Tomahawk had made the required CTAF broadcast approaching Hoxton Park. There CTAF frequency was not recorded nor was it required to be recorded. The pilot may have made the required CTAF broadcast before the pilot of the Archer had changed to that frequency. Nevertheless, the pilot of the Tomahawk should have heard the pilot of the Archer reporting inbound to Hoxton Park and been aware of the approximate location of that aircraft. Had the pilot of the Tomahawk acknowledged the broadcast from the pilot of the Archer, the situational awareness of that pilot would have been enhanced, making his efforts to sight and avoid other aircraft more effective.

Significant Factors

  1. The pilot of the Archer was unaware of the presence of the Tomahawk and subsequently did not see that aircraft in time to avoid a collision.
  2. The pilot of the Tomahawk did not see and avoid the Archer.
  3. The CTAF requirement for only one broadcast from an approaching aircraft reduced the possibility for a pilot to receive location-specific information about another conflicting aircraft, thus reducing the opportunity of sighting that aircraft.

Safety Action

As a result of this accident and a later collision on Hoxton Park aerodrome, the following recommendations were issued to the Civil Aviation Safety Authority on 15 June 1999:

"IR990077
The Bureau of Air Safety Investigation recommends that the Civil Aviation Safety Authority increase the number of mandatory broadcasts to include a set of critical location broadcasts for those locations where the risk of collision is increased.

IR990078
The Bureau of Air Safety Investigation recommends that the Civil Aviation Safety Authority extend the proposed radio requirements as outlined in the Notice of Proposed Rulemaking (NPRM9702RP) to include both licensed aerodromes and any unlicensed aerodrome into which fare-paying passenger services operate.

IR990079
The Bureau of Air Safety Investigation recommends that the Civil Aviation Safety Authority amend current procedures/airspace for aircraft operating into and departing from Hoxton Park in order to reduce the potential for further aircraft collisions".

General details
Date: 06 June 1998   Investigation status: Completed  
Time: 1104 hours EST    
Location   (show map): 2 km NE Hoxton Park, Aero.    
State: New South Wales   Occurrence type: Airborne collision  
Release date: 24 December 1999   Occurrence category: Accident  
Report status: Final   Highest injury level: Fatal  

Aircraft 1 details

Aircraft 1 details
Aircraft manufacturer Piper Aircraft Corp  
Aircraft model PA-28  
Aircraft registration VH-UZR  
Serial number 28-8190154  
Type of operation Private  
Damage to aircraft Substantial  
Departure point Hoxton Park, NSW  
Departure time 1030 hours EST  
Destination Hoxton Park, NSW  
Crew details
Role Class of licence Hours on type Hours total
Pilot-in-Command Private 174.8 502

Aircraft 2 details

Aircraft 2 details
Aircraft manufacturer Piper Aircraft Corp  
Aircraft model PA-38  
Aircraft registration VH-FTX  
Serial number 38-79A0268  
Type of operation Private  
Damage to aircraft Destroyed  
Departure point Bankstown, NSW  
Departure time 1010 hours EST  
Destination Bankstown, NSW  
Crew details
Role Class of licence Hours on type Hours total
Pilot-in-Command Private 103.4 125
 
Injuries
  Crew Passenger Ground Total
Fatal: 1 1 0 2
Total: 1 1 0 2
Last update 13 May 2014