Aviation safety investigations & reports

Controlled flight into terrain involving Kavanagh Balloons G-525, VH-HVW, Pokolbin, New South Wales, on 30 March 2018

Investigation number:
AO-2018-027
Status: Completed
Investigation completed
Phase: Final report: Dissemination Read more information on this investigation phase

Final Report

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What happened

At about 0710 Eastern Daylight-saving time[1] on 30 March 2018, a Kavanagh Balloons G-525 balloon, registered VH-HVW (HVW) and operated by The International Balloon Flight Company (Australia), launched from a site near Pokolbin, New South Wales for a planned 1-hour scenic flight. HVW was one of three balloons launched by the company from the same site. After climbing through fog to about 2,000 ft and realising how far the fog layer extended, the pilot of HVW, along with the other two pilots, decided to abort the flight and descend for a landing at the nearest suitable site. On approach to land in low‑visibility conditions, HVW collided with trees, which caused the basket to rotate 180 degrees. It then landed heavily, resulting in injuries to 16 of the 24 passengers, three of them serious. The pilot was uninjured and 74 of the balloon’s panels required patching or repair.

What the ATSB found

The three pilots decided to launch despite forecast fog and the development of fog at the launch site, without an awareness of its extent. This resulted in the balloons being above a layer of fog through which they had to descend.

The descent in low-visibility conditions diminished the pilot of HVW’s ability to see trees in the approach path. This, combined with a 12 kt wind at the landing site, resulted in the pilot having insufficient time to manoeuvre the balloon to climb above the trees after sighting them.

More generally, the visual flight rules permitted balloons to arrive and depart in foggy conditions without assurance that sufficient visibility existed to see and avoid obstacles.

The pilot and ground crew did not follow the operator’s documented emergency procedures to not move injured passengers after the accident, increasing the risk of exacerbating their injuries.

What's been done as a result

The balloon operator amended their operations manual to include pilot actions in the event of extensive fog or low cloud forming after take-off. They also added fog as a local known hazard to their Hunter Valley operations, describing where fog is likely to occur and the best vantage point from which to assess its development.

The Civil Aviation Safety Authority (CASA) has drafted an advisory circular (AC) to provide guidance for balloon operators and pilots regarding weather assessment and low-visibility operations. CASA intends to publish the AC in 2020.

Finally, the ATSB has issued a recommendation that CASA undertake a risk assessment of the reduced visibility exemption to the visual flight rules for balloons, to determine whether it is adequately safe.

Safety message

It is vital that pilots obtain a full appreciation of the weather for the duration of the planned flight from the Bureau of Meteorology, which is the approved source of aviation meteorology products. The ultimate responsibility for a pilot’s decision on whether to launch or not (go/no-go decision) rests with the pilot. This decision needs to address factors and limitations related to the pilot, balloon, environment and operation.

CASA has issued a Civil Aviation Advisory Publication that encourages balloon operators to train and assess ground crew members in accordance with the requirements for flight crew. This would assist operators to assure that all crewmembers meet a competency standard documented in their emergency procedures on a periodic basis.

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  1. Eastern Daylight-saving Time (EDT): Coordinated Universal Time (UTC) + 11 hours.
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The occurrence

Context

Safety analysis

Findings

Safety issues and actions

Pilot details

Sources and submissions

Preliminary report

Preliminary report published: 8 June 2018

Sequence of events

Early on the morning of 30 March 2018, the senior base pilot, acting as the duty pilot of The International Balloon Flight Company’s Hunter Valley operation, prepared to conduct a one-hour scenic balloon flight along with two other balloons operated by company pilots.

The pilots reported reviewing the forecast and actual weather conditions from three different sources and assessed the conditions as suitable for the flight. The pilot of one of the balloons, a Kavanagh Balloons G-525, registered VH-HVW (HVW), reported noting at the time that the temperature and dewpoint[1] were very close, which can be conducive to the formation of fog. There had also been significant recent rainfall and the ground was moist.

At about 0500 Eastern Daylight-saving Time,[2] the pilots met and briefed their passengers in Pokolbin, New South Wales. There were 24 passengers for HVW (and 19 and 20 for the other two balloons). A pi-ball[3] was launched to assess the wind direction and strength, and the visibility. All three pilots reported that the sky was clear at that time.

The pilots and passengers were then transported by bus to a possible launch site, where a second pi-ball was launched. The pilots reported that the sky was still clear at this time. Based on the wind conditions, the pilots elected to continue to a third site (Peppers Creek) and after launching a third pi-ball, decided they would launch the balloons from there (Figure 1). At Peppers Creek, the pilots completed their briefing of the passengers. This included a demonstration of the position to be adopted for landing. The passengers were then required to show that they could assume the correct position.

Figure 1: Map of the area showing launch and landing sites

Figure 1: Map of the area showing launch and landing sites. Source: Google earth annotated by ATSB

Source: Google earth annotated by ATSB

The pilots reported that the sky was still clear at Peppers Creek when they started to inflate the balloons, but that some light mist was rolling in. The senior base pilot drove to a location about 3.5 km to the north-west to assess the conditions in the area. He took a photo (Figure 2), which he sent to the other two pilots and, following receipt of this, they each elected to launch the three balloons from Peppers Creek.

Figure 2: Photo taken prior to take-off by senior base pilot

Figure 2: Photo taken prior to take-off by senior base pilot. Source: Provided to ATSB

Source: Provided to ATSB

At about 0704, HVW lifted off and soon after the other two balloons followed. The pilot of HVW reported that there was a thin layer of low cloud but the visibility was adequate. Photos provided by the passengers showed fog in the area during and just after take-off (Figures 3a and 3b).

Figure 3a: View of company balloons from VH-HVW, airborne at about 0704
Figure 3a: View of company balloons from VH-HVW, airborne at about 0704. Source: Provided to ATSB
Source: Provided to ATSB

 

Figure 3b: View from VH-HVW shortly after take-off
Figure 3b: View from VH-HVW shortly after take-off. Source: Provided to ATSB

 

Source: Provided to ATSB

The balloons climbed above the fog (Figure 3b), to about 2,000 ft above mean sea level (AMSL). The pilot of HVW reported that the low-level cloud was rolling in from the north and getting thicker. About 10 to 15 minutes after take-off, the senior base pilot radioed the other two pilots to advise them to abort the flight. All three pilots decided to land as soon as practicable, as the conditions were worsening.

The pilot of HVW commenced descent, aiming to land at a landing site known as Hope West, at an elevation of about 300 ft AMSL. At 0717, as the balloon descended, the pilot received a phone call from the pilot of another local balloon operator asking whether the conditions were suitable for flight. He responded in the negative and the other pilot elected not to take-off.

As HVW descended below about 900 ft AMSL, it entered cloud. The pilot was unable to see the ground and used the map on his iPad to locate his planned landing site as he maintained a descent rate of about 100 ft per minute. He sighted the ground when about 100 ft above it and levelled the balloon out. The pilot could see a tank, which was also represented on the iPad map. From this, he was able to determine that the clearing he was aiming for was about 100 m ahead, across a road bordered by trees.

The pilot estimated that his visibility at that stage was about 5 m and that the balloon was travelling at about 12 kt. He found the motion of the cloud very disorientating.

At about 15 m above the ground, a number of passengers sighted a road and trees ahead and called out a warning to the pilot. The pilot saw the trees and reported activating full burners to try and out-climb them, but the balloon collided with the trees. The collision resulted in several large tears to multiple panels of the balloon fabric in the lower section of the balloon envelope. The impact with the trees also resulted in the basket rotating 180 degrees.

The pilot called out to the passengers to brace for landing. At about 0728, the balloon landed heavily, beyond the trees with the basket upright. All of the occupants were facing forwards in the direction of travel as the balloon contacted the ground, instead of the normal rearwards facing landing position.

Sixteen passengers were injured in the landing, three of them seriously. A ground crewmember transported three passengers to Cessnock Hospital, two of whom were then transferred to John Hunter Hospital with spinal injuries. The balloon was substantially damaged, requiring repairs to the fabric of the balloon envelope (Figure 4).

The second company balloon landed without incident about 10 minutes later in the same clearing, but a few hundred metres beyond HVW. The senior base pilot landed his balloon, also without incident near Cessnock aerodrome.

Figure 4: Damage to balloon VH-HVW

Figure 4: Damage to balloon VH-HVW. Source: Provided to ATSB

Source: Provided to ATSB

Pilot information

The pilot held a commercial pilot licence (balloon) and a valid Class 2 medical certificate. He had accrued a total of 3,120 flying hours and 25 hours on the balloon type, 15 of which had occurred in the 90 days prior to the accident.

Balloon information

VH-HVW is a Kavanagh Balloons G-525 balloon. It has a volume of 14,866 cubic metres (525,000 cubic feet), the capacity to carry a pilot and 24 passengers, and has a Lite Vent deflation system and rotation vents. The basket is a double tee basket (Figure 6), 1.6 m by 5.6 m in dimension. The operator’s first recorded flight in the balloon was on 10 December 2017.

Figure 5: Kavanagh Balloons G-525 balloon, registered VH-HVW

Figure 5: Kavanagh Balloons G-525 balloon, registered VH-HVW. Source: Kavanagh Balloons

Source: Kavanagh Balloons

Figure 6: Double tee basket

Figure 6: Double tee basket. Source: Kavanagh Balloons

Source: Kavanagh Balloons

Rotation vents

Rotation vent lines enable the pilot to open rotation vents that rotate the balloon in either direction. Thus the pilot can orientate the long side of the basket across the direction of travel for landing, with the passengers facing rearwards.

Figure 7: Rotation vent lines

Figure 7: Rotation vent lines. Source: Kavanagh Balloons

Source: Kavanagh Balloons

Weather and environmental information

The Bureau of Meteorology provided the ATSB with a report detailing the forecast and actual weather conditions for the flight.

The area forecast issued at 0322 on 30 March and valid from 0400 to 1000, included visibility reducing to 500 m in scattered[4] fog over land, and broken stratus with bases at 1,500 ft and tops at 4,500 ft.

The grid point wind and temperature forecast valid at the time of the flight for 1,000 ft AMSL included north-north-easterly winds at 6 kt and temperature 20 °C, and at 2,000 ft, north-easterly winds at 5 kt and temperature 21 °C.

The terminal aerodrome forecast (TAF)[5] for Williamtown, 49 km east of the accident site, current at the time of launch included a 30 per cent probability of fog between 0500 and 0900 and broken cloud at 200 ft AGL, north‑westerly wind at 5 kt and scattered cloud at 1,500 ft and a temperature of 19 °C.

The TAF for Maitland, 18 km east-north-east of the accident site, current at the time of launch, included variable wind at 3 kt, fog with visibility 500 m and broken cloud at 200 ft AGL, becoming west-north-westerly at 5 kt and scattered at 2,500 ft between 0700 and 0900.

The observation at 0700 for Cessnock aerodrome was nil wind, temperature and dew point 15 °C and for Maitland was nil wind, overcast at 400 ft AGL and temperature and dew point 19 °C.

Satellite imagery showed low cloud and fog developing from 0200 in a south-easterly band from Scone to Williamtown and becoming more extensive until it started to dissipate after 0900. Figure 7 shows the fog and low cloud in the area at 0700.

Figure 7: Satellite imagery showing a band of fog and low cloud at 0700

Figure 8: Satellite imagery showing a band of fog and low cloud at 0700. Source: Bureau of Meteorology

Source: Bureau of Meteorology

Visibility requirements

The Airservices Australia Aeronautical Information Package En Route 2 – Visual meteorological conditions (VMC) – take-off, en route and landing, 2.5 Non-controlled airspace – Class G, states that for balloons in day operations, below 500 ft above ground or water, the minimum flight visibility required is 100 m, provided the balloon is at least 10 NM from an aerodrome with an approved instrument approach procedure. The launch site at Peppers Creek was about 11 NM from Maitland Airport (which has an instrument approach), with the landing site being about 10 NM away. Cessnock Airport does not have an instrument approach.

Between 500 and 1,500 ft above ground or water, 5,000 m flight visibility is required and the balloon is to remain clear of cloud. However, no vertical clearance from cloud below the balloon is required, provided that the top of the cloud is at or below 500 ft above ground or water, and the balloon is at least 10 NM from an aerodrome with an approved instrument approach procedure.

At or below the higher of 3,000 ft AMSL or 1,000 ft AGL, flight visibility of 5,000 m is required, and the balloon must remain clear of cloud and in sight of ground or water.

Landing position and injuries

The basket landed upright, with all occupants facing forwards. The pilot had demonstrated the landing position (Figure 8) prior to departure and most passengers reported adopting that position for landing. In one of the four compartments, a passenger reported that they stood in front of their partner. Some passengers seated themselves on the floor of the basket prior to the impact with the ground.

Figure 8: Landing position – knees bent and holding onto handles

Figure 9: Landing position – knees bent and holding onto handles. Source: Kavanagh Balloons

Source: Kavanagh Balloons

Related occurrences

The ATSB is currently investigating a hard landing involving Kavanagh Balloons B425, VH-OKX, also operated by The International Balloon Flight Company (Australia), which occurred on 13 January 2018 (AO-2018-004). During landing in windy conditions, the balloon landed hard and struck vegetation. The ATSB is assessing the similarities between the accidents and reviewing the effectiveness of actions taken in response to the January occurrence.

Continuing investigation

The investigation is continuing and will include examination of the following:

  • interviews and other material obtained from passengers and involved parties
  • weather conditions and go/no-go decision making
  • the balloon’s maintenance and technical records
  • the operator’s procedures
  • survivability including assessment of injuries and basket position/loading
  • previous research and similar occurrences, and
  • regulatory oversight of the operation.

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The information contained in this update is released in accordance with section 25 of the Transport Safety Investigation Act 2003 and is derived from the initial investigation of the occurrence. Readers are cautioned that new evidence will become available as the investigation progresses that will enhance the ATSB's understanding of the accident as outlined in this update. As such, no analysis or findings are included in this update.

 

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  1. Dewpoint: the temperature at which water vapour in the air starts to condense as the air cools. It is used, among other things, to monitor the risk of aircraft carburettor icing or the likelihood of fog.
  2. Eastern Daylight-saving Time (EDT): Coordinated Universal Time (UTC) + 11 hours.
  3. A pi-ball is a pilot balloon filled with helium, which has an LED light attached. It is used to indicate wind direction and speed and visibility.
  4. Cloud cover: in aviation, cloud cover is reported using words that denote the extent of the cover – few indicates that up to a quarter of the sky is covered, scattered indicates that cloud is covering between a quarter and a half of the sky, broken indicates that more than half to almost all the sky is covered, and overcast indicates that all the sky is covered.
  5. A TAF is a coded statement of meteorological conditions expected at an aerodrome and within a radius of five nautical miles of the aerodrome reference point.

Safety Issue

Go to AO-2018-027-SI-01 -

Balloon visual meteorological conditions

The visual flight rules permitted balloons to arrive and depart in foggy conditions without assurance that sufficient visibility existed to see and avoid obstacles.

Safety issue details
Issue number: AO-2018-027-SI-01
Who it affects: All balloon operators of charter flights
Status: Open – Safety action pending
General details
Date: 30 March 2018   Investigation status: Completed  
Time: 0728 EDT   Investigation level: Defined - click for an explanation of investigation levels  
Location   (show map): Pokolbin, near Cessnock   Investigation phase: Final report: Dissemination  
State: New South Wales   Occurrence type: Controlled flight into terrain (CFIT)  
Release date: 11 August 2020   Occurrence category: Accident  
Report status: Final   Highest injury level: Serious  

Aircraft details

Aircraft details
Aircraft manufacturer Kavanagh Balloons  
Aircraft model G-525  
Aircraft registration VH-HVW  
Serial number G525-535  
Operator The International Balloon Flight Company (Australia)  
Type of operation Charter  
Sector Balloon  
Damage to aircraft Substantial  
Departure point Peppers Creek, New South Wales  
Destination Hope West, New South Wales  
Last update 11 August 2020