First phase of the flight
On 11 March 2020, Air Connect Australia was operating a Cessna 404, registered VH-OZO, on a passenger charter flight from Cairns to Lockhart River and return (Figure 1). The client arranged for the aircraft to depart Cairns at 0730 Eastern Standard Time with four passengers, wait on the ground at Lockhart River for about 5 hours, then depart at 1430 with the same passengers for the return flight. The operator assigned the pilot who regularly conducted the client’s charter flights.
Source: Google Earth, annotated by the ATSB
According to the weather forecasts, the pilot could expect mostly visual meteorological conditions (VMC) during the day at Cairns with some periods of rain showers and low cloud. For the arrival at Lockhart River, the forecast weather was predominately VMC but there were overlapping periods of rain and low cloud with 30 per cent probability of thunderstorms.
The pilot had submitted a flight notification, which specified instrument flight rules (IFR) and capability for an area navigation (RNAV) instrument approach. On the morning of the flight, the pilot refuelled the aircraft with 650 L of avgas.
The aircraft departed Cairns at 0719 and the pilot tracked for the first planned waypoint on climb to 10,000 ft above mean sea level. Based on the forecast winds, the estimated time of arrival (ETA) at Lockhart River was 0852. As the flight progressed, the pilot amended the ETA to 0904.
At 0840, the pilot advised air traffic control that he was leaving 10,000 ft on descent to Lockhart River. A couple of minutes later, the controller advised the pilot of the very high frequency (VHF) and high frequency (HF) radio frequencies applicable to the rest of the flight. That was the controller’s last contact with the pilot and no further routine interactions with the controller were expected.
During descent, the pilot transmitted on the common traffic advisory frequency (CTAF) for Lockhart River to enable the pilot activated lighting (PAL) for a period of 30 minutes. At 0852, the aerodrome frequency response unit (AFRU) broadcast ‘Lockhart River CTAF, runway lights are on.’
As the aircraft was descending, the pilot tracked to waypoint LHREB, one of three initial approach fixes for the RNAV (GNSS) runway 30 instrument approach at Lockhart River.
First approach at Lockhart River
Note: Figure 2 and Figure 4 provide information on the pilot’s first approach and Figure 3 and Figure 4 provide information on the second approach. Figure 11 shows the applicable approach chart, and key parameters for the approaches are incorporated into Figures 2, 3 and 4.
The aircraft flightpath parameters referenced in the following text and shown in Figures 2, 3, and 4 are taken from transmitted GPS data recorded at 5-second intervals by an electronic flight bag application. The quoted heights are geometric altitudes rather than barometric altitudes indicated by an altimeter, which is the primary altitude reference for this approach. The ATSB notes that GPS altitude was transmitted as a rounded value so the recorded altitude could vary up to 100 ft from the actual GPS-computed geometric altitude. Preliminary validation of the flight data indicates that the recorded geometric altitudes correlate with barometric altitude data that is available for part of the flight.
The pilot passed abeam LHREB at 0859:38 on descent through 5,400 ft and turned left to track to the runway in accordance with the RNAV procedure.
At 0901:25, the pilot made a radio broadcast on the CTAF, advising the aircraft was 10 NM to the south-east of the aerodrome, inbound to runway 30 and on descent passing 4,000 ft. Shortly afterwards, the aircraft passed intermediate approach fix LHREI at 4,000 ft.
The pilot continued the descent and inbound track to pass the final approach fix LHREF on descent through 2,300 ft. At 0904:27, the pilot broadcast on the CTAF that he was 5 NM out and on final (approach) to runway 30.
The aircraft arrived at the missed approach point LHREM at 0906:17 and 570 ft. The specified minimum descent altitude (MDA) was 830 ft, which could be lowered by 100 ft if the pilot set the current aerodrome QNH from the automated weather information service (AWIS). The pilot continued the descent to 500 ft then climbed to 600 ft and maintained the approach track for a further 2 NM. Coincident with passing over the aerodrome facilities, the pilot initiated a missed approach and, while climbing, turned slightly right to track to the missed approach turning fix LHREH.
At 0907:22, the pilot broadcast on the CTAF that he was conducting a missed approach for runway 30, tracking to the west then turning back to the east and climbing to 3,500 ft.
After passing LHREH at 0907:43 on climb through 1,200 ft, the pilot made a right turn to track to the east as prescribed by the approach chart. At 0908, the pilot contacted Flightwatch on HF to advise of the missed approach and his intention to provide an update of ‘operations normal’ by 0930. The middle part of this radio transmission, as recorded by Airservices Australia, was unclear, which is not uncommon for HF radio communication. Based on the fragments and context, the pilot was probably advising his intention to conduct another approach.
The pilot continued the climb to 3,500 ft as specified for the missed approach procedure.
Source: Google Earth, annotated by the ATSB
Second approach at Lockhart River
Following the missed approach, the pilot levelled the aircraft at 3,500 ft and turned from the easterly heading towards the closest initial approach fix LHREA. At 0912:51, the AFRU recorded runway lights on, consistent with the pilot reactivating the runway lights for another 30-minute period.
About 2 NM from LHREA, the pilot turned right toward the general direction of intermediate approach fix LHREI and tracked to the south-west for about 2 NM then turned left to intercept the defined inbound track to LHREI. The pilot started descent from 3,300 ft at 0915:18.
At 0915:50, the pilot made another inbound broadcast on the CTAF advising:
10 miles [NM] to the south-east on descent passing three thousand eight hundred [3,800 ft] [unclear phrase, possibly ‘correction’] two thousand eight hundred [2,800 ft], straight-in approach runway three zero , circuit area two one [time 0921].
At the start of the transmission, the aircraft was on descent through 2,900 ft. The ATSB notes that the recorded transmission sounded routine; no further transmissions from VH-OZO were recorded.
After passing over LHREI, the pilot flew parallel to the defined RNAV approach track and continued the descent at a similar gradient to the first approach. About halfway between LHREI and final approach fix LHREF, the aircraft descended through the segment minimum safe altitude of 1,800 ft.
When the aircraft passed LHREF at 0918:23, the aircraft was on descent through 1,100 ft. From LHREF to LHREM, the altitude limitation was the MDA of 730 ft (assuming the pilot had set the current QNH). About 30 seconds later, the aircraft was approaching 700 ft with an apparent decrease in the descent rate for a short period. The aircraft then descended below the MDA and the aircraft track diverged to the left, crossing the inbound track at an angle of about 20°.
The divergent aircraft track and descent continued until the aircraft impacted a sand dune on the coastline at 0919:40. The pilot and four passengers were fatally injured and the aircraft was destroyed.
Source: Google Earth, annotated by the ATSB
Profile and speed information
The descent profile of the aircraft on the first approach was slightly higher than the nominal 3° approach gradient specified on the approach chart. The descent profile of the aircraft on the second approach had a similar gradient but was generally displaced 1,200 ft lower.
The ATSB calculated the average groundspeed of the aircraft from the distance travelled between data points in the specified time. This is provisional data that requires further adjustment for the effects of wind, altitude, and temperature to derive estimates of aircraft airspeed.
On the first approach, the groundspeed was between 130 and 140 kt until the missed approach was initiated. On the second approach, the groundspeed was also between 130 and 140 kt until it increased to 150 kt as the aircraft descended below the MDA up to the collision with terrain.
Note: Short periods of constant altitude represented in the diagram do not necessarily indicate a constant altitude because the transmitted/recorded data is rounded.
Site and wreckage
The accident site was located on a sand bank adjacent to the beach, about 6 km south-east of Lockhart River Aerodrome and 300 m to the south-west of the specified RNAV track. The wreckage trail was about 20 m from the initial impact point (Figure 5), and indicated that the aircraft was on a heading of about 280° (magnetic), with the impact point about 30 ft above mean sea level.
The ATSB’s on-site examination of the wreckage, damage to surrounding vegetation and ground markings indicated that at initial impact the aircraft was:
- upright and close to wings level
- about 5° nose down
- at relatively high speed.
An area of foliage around the aircraft displayed signs of chemical burn from avgas, indicating that the aircraft had a significant amount of fuel on board.
There was no evidence of any structural or mechanical defects, but the examination was limited by the extensive damage (Figure 6). All but one of the propeller blades were located at the site; damage to the recovered blades indicated significant rotational energy at impact consistent with both engines operating normally with substantial power.
The landing gear was extended at the time of impact. Other aircraft configuration information such as flap position, trim settings and switch selections could not be validated due to the impact damage. The serviceability of the flight instruments and associated systems could also not be verified.
The only components on the aircraft that may have recorded data were a digital fuel flow indicator/totaliser and a transponder, and the ATSB recovered these components. After consideration of the damage to these components and the potential value of any data, no further examination was undertaken.
Pre-flight planning and in-flight monitoring
At 1326 on the day before the accident flight, the pilot accessed a location briefing for Lockhart River from the National Aeronautical Information Processing System (NAIPS) via an electronic flight bag (EFB) application. This type of briefing typically displayed current forecasts, reports, and ‘notice to airmen’ (NOTAM) applicable to the nominated location.
Later that day, at 1830, the pilot requested grid point wind and temperature charts (GPWT) and a specific pre-flight information bulletin (SPFIB) from NAIPS via flight planning software. The SPFIB request was for Cairns to Lockhart River and return with the estimated time of departure nominated as 1930 the same day. This bulletin was valid until 1830 on the day of the accident.
A printout of the SPFIB found at the accident site showed aerodrome forecast (TAF) and weather reports (METAR) for Cairns. The weather for the next day (day of accident flight) at Cairns Airport was expected to be visibility of 10 km or greater and showers of light rain with scattered cloud at 1,800 ft in the morning lifting to 2,500 ft. In addition, the forecast imposed a TEMPO for the next day to specify periods of visibility reduced to 2,000 m with showers of moderate rain and broken cloud at 1,000 ft.
On the printout of the SPFIB, a METAR for Lockhart River for 1800 (10 March) showed light winds, visibility 10 km or greater and nil cloud detected. Since 0900 that morning, recorded rainfall was 1.8 mm.
No TAF was provided on the SPFIB for Lockhart River as the time of the request was outside the issue and validity period. There were no predicted outages of global positioning system/global navigation satellite system (GPS/GNSS) capability for Cairns or Lockhart River. ‘Notice to airmen’ (NOTAM) information included a change to Lockhart River runway distance and gradient data and no other notices with significance for the planned flight.
After the SPFIB was received, at 1942, the pilot submitted a flight notification for the planned departure from Cairns at 0730 the next morning to Lockhart River followed by a departure at 1430 for the return sector. Both sectors were planned under instrument flight rules (IFR) with nominated capability for instrument approaches using GPS/GNSS equipment.
A damaged and partly illegible copy of the pilot’s flight plan/log was found at the accident site. This was a printout from flight planning software showing key navigational data and pilot notes on progress of the flight. There was no indication of any operational abnormalities.
A tabulated fuel plan showed 1,040 L on board at engine start at Cairns and expected fuel consumption of 285 L for the planned 94-minute flight to Lockhart River. The pilot had included provision for 45 minutes fixed reserve (124 L), 40 L variable reserve and 60 minutes holding (110 L) if required (consistent with TEMPO conditions). If the variable reserve and holding allowance was consumed on the outbound sector (in addition to the calculated flight fuel), the remaining 605 L was sufficient to return to Cairns with allowance for 60-minutes holding on arrival.
In summary, the pilot was not intending to refuel at Lockhart River, and the aircraft had sufficient fuel to conduct the flight from Cairns to Lockhart River and return, with additional fuel for holding on both sectors if required. Avgas was available at Lockhart River.
The pilot completed the operator’s passenger/cargo manifest form and calculated the aircraft’s weight and balance with reference to individual passenger weights and baggage. The take-off weight was recorded as 3,678 kg and nominal landing weight as 3,366 kg. The aircraft’s maximum take-off weight was 3,810 kg and maximum landing weight was 3,674 kg. The graphical trimsheet showed the centre of gravity was within limits throughout the flight.
A copy of the operator’s in-flight monitoring form was found at the accident site. When the pilot completed the form in cruise at 10,000 ft, all of the recorded engine parameters for each engine were comparatively similar with no indication of any aircraft-related problems.
After the pilot requested the SPFIB and submitted the flight notification on the evening before the accident flight, there was no record of further requests for meteorological information from NAIPS. Such information is also available from the Bureau of Meteorology website and other sources without any user registration requirements. It was reported that the pilot was aware of the current weather forecasts on the morning before the flight.
During the flight, the pilot was using an iPad with an electronic flight bag (EFB) application and was carrying a second iPad as a backup.
The Bureau of Meteorology produced aviation forecasts, observations, warnings and advisories. As the official provider of the Aeronautical Information Service, Airservices Australia delivered the bureau’s aviation meteorological products to pilots through NAIPS.
For the flight from Cairns to Lockhart River, the essential meteorological data was aerodrome forecast (TAF), graphical area forecast (GAF), grid point wind and temperature chart (GPWT) and any warnings (such as SIGMET). This could be supplemented by aerodrome weather reports (METAR), ground-based weather radar imagery, and satellite imagery.
Forecasts for Lockhart River
On 11 March 2020 (day of accident), the initial TAF for Lockhart River was issued at 0449 EST and was valid from 0600 to 1800. The expected weather conditions were:
- From 0600 to 1000: wind variable at 3 kt with visibility 10 km or greater. Light rain showers and cloud scattered at 1,000 ft (all heights are above the aerodrome elevation).
- Between 0600 and 1000: TEMPO - visibility reduced to 3,000 m with rain and broken cloud at 500 ft.
- From 0600 to 0800: 30 per cent probability of fog with visibility reduced to 500 ft and broken cloud at 100 ft.
- From 1000 to 1800: wind from the north-east at 5 kt with visibility 10 km or greater. Light rain showers with scattered cloud at 1,000 ft.
- Between 1000 and 1800: TEMPO - visibility reduced to 3,000 m with rain showers and broken cloud at 800 ft.
- For the whole forecast period, 0600 to 1800: 30 per cent probability TEMPO - winds gusting 25 to 35 kt and visibility reduced to 1,000 m due to thunderstorms and rain. This was associated with broken cloud at 500 ft and scattered cumulonimbus cloud with the base at 1,000 ft.
Based on this forecast, for a flight expected to arrive at between 0900–1000, the pilot was required to plan for 60 minutes or diversion to an alternate. The aircraft had more than sufficient fuel for that purpose.
An amended TAF for Lockhart River was issued at 0925 and was valid from 0900 to 1800. The expected weather conditions were:
- From 0900 to 1300: wind variable at 3 kt with visibility 10 km or greater. Light rain showers with cloud scattered at 1,000 ft and broken at 2,000 ft
- For whole forecast period, 0900 to 1800: TEMPO – winds gusting from 20 to 35 kt and visibility reduced to 1,000 m due to thunderstorms and rain. This was associated with broken cloud at 500 ft and scattered cumulonimbus cloud with the base at 1,500 ft.
A GAF was issued at 0853 and was valid from 0900 to 1500 and applicable from surface to 10,000 ft. This covered the Queensland-North region, which was divided into six areas for this forecast. Most of the flight including the arrival at Lockhart River was within one area that was forecast to have the following conditions:
- Broken stratus 1,000 ft to 2,000 ft with broken cumulus/stratocumulus above that. Visibility reduced to 6,000 m in widespread rain.
- Isolated towering cumulus from 2,000 ft, broken stratus from 800 to 2,000 ft, and broken cumulus/stratocumulus from 2,000 ft. Visibility reduced to 2,000 ft in scattered rain showers.
- Isolated cumulonimbus from 2,000 ft and broken status between 500 ft and 1,000 ft. Visibility reduced to 500 m in isolated thunderstorm rain showers.
A GPWT forecast was issued at 0538 and was valid to 1000. Lockhart River was located near the intersection of four data boxes and therefore roughly equidistant from four forecast locations. Taking 2,000 ft as a reference height for the approaches and coastal data as more relevant, the wind was forecast to be from the north-west at 9 kt increasing to 21 kt north of Lockhart River.
There were no significant weather warnings applicable to the flight.
Aerodrome weather reports for Lockhart River
The METARs for Lockhart River were automatically generated every 30 minutes for routine reports and were issued as a special report (SPECI) at other times when one or more elements met specified criteria for degradation and improvement. For the period from 0830 to 0930 on 11 March 2020:
- 0830: nil wind, visibility 10 km or greater with rain and scattered cloud from 3,000 ft. Temperature and dewpoint were both 25 °C. Rainfall in the previous 10 minutes was 0.4 mm.
- 0900: nil wind, visibility 10 km or greater with rain and broken cloud at 2,000 ft, 3,500 ft, and 4,100 ft. Temperature and dewpoint were both 25 °C. Rainfall in the previous 10 minutes was 0.4 mm.
- SPECI 0910: nil wind, visibility 10 km or greater with rain and broken cloud at 1,800 ft and 3,400 ft then overcast at 4,200 ft. Temperature and dewpoint were 26 and 25 °C respectively. Rainfall in the previous 10 minutes was 0.4 mm.
- SPECI 0913: nil wind, visibility 3,800 m with rain and broken cloud at 1,800 ft and 3,400 ft, overcast at 4,200 ft. Temperature and dewpoint were 26 and 25 °C respectively. Rainfall in the previous 10 minutes was 0.2 mm.
- SPECI 0929: westerly at 5 kt, visibility 8,000 m with heavy rain and scattered cloud at 1,200 ft, broken cloud at 1,900 ft, and broken cloud at 3,600 ft. Temperature and dewpoint were both 25 °C . Rainfall in the previous 10 minutes was 0.4 mm.
- SPECI 0930: westerly at 5 kt, visibility 9,000 m with heavy rain and scattered cloud at 1,200 ft, broken cloud at 1,900 ft and broken cloud at 3,600 ft. Temperature and dewpoint were both 25 °C . Rainfall in the previous 10 minutes was 0.4 mm.
The QNH remained at 1,008 hPa during this period, except at 0929 when it was reported as 1,009.
During the next 30 minutes, there were four SPECI issued with variations to visibility between 5,000 m and 10 km or greater. The wind varied in direction and strength no greater than 7 kt. The temperature and dewpoint both remained at 25°. There was persistent rain, and scattered to broken low cloud.
Automated weather information service
Lockhart River was equipped with an automated weather information service (AWIS) that transmitted text-to-speech on a discrete VHF frequency. A new AWIS message was generated every minute in a similar format to the METAR reports. This data was also available from a telephone service.
The pilot recorded the following data in the space allocated for arrival weather information in the flight plan/log:
- calm (nil wind)
- 10 km (visibility)
- B1800 (broken cloud at 1,800 ft)
- B3500 (broken cloud at 3,500 ft)
- OV 5300 (overcast cloud at 5,300 ft)
- 1008 (QNH)
- 25 (temperature 25 °C).
Figure 7 provides an indication of the weather around Lockhart River at 0930 on the morning of the accident.
Source: Bureau of Meteorology, annotated by the ATSB
Local weather observations
Two pilots were operating aircraft in the Lockhart River area before and after the accident. The first pilot, operating before the accident, tracked to Lockhart River from the south and conducted the RNAV (GNSS) RWY 30 approach, landing at 0810. There were intermittent rain showers in the area and the pilot advised that the end of the runway was visible while descending through 1,000 ft. The pilot remained on the ground at Lockhart River until later in the day and heard an aircraft (VH-OZO) fly over at high engine power. At that time, there was scattered low cloud at 500–1,000 ft with reduced visibility in rain showers.
The following pilot, operating after the accident, tracked to Lockhart River from the south-west and diverted 15 NM to the right of track due to weather. On arrival the pilot conducted the Lockhart River RNAV (GNSS) RWY 30 approach and landed at 0953. There was rain in the area and, although the conditions allowed visual navigation after the final approach fix while descending through 1,500 ft, the runway was not visible until later in the approach.
A person who was near the aerodrome at the time of the accident described the conditions as an unusual morning with a bit of mist coming from the rainforest, and that there was about 5 to 10 minutes of heavy rain around the time the aircraft would have been in the area. At that time, there was low-lying cloud and no wind.
Two of the passengers recorded and shared images during the flight, including one image from each passenger while the aircraft was in the Lockhart River area. The first image (Figure 8) was sent by text messaging at 0903, which was during the first approach while the aircraft was over halfway between intermediate approach fix LHREI and final approach fix LHREF at an altitude between 3,100 and 2,500 ft. The camera is orientated to the north so the foreground, if visible, would be the ocean to the east of Lockhart River.
In a subsequent text message sent at 0914, the passenger advised that the first attempt at landing was unsuccessful and the runway was not visible due to heavy rain. This was followed a couple of minutes later by a text to advise of another attempt. No further communication was received.
Source: Provided to the ATSB, lower section of image cropped by the ATSB
The second image (Figure 9) was uploaded at 0914 during the early stages of the second approach, while the pilot was tracking towards LHREI on a south-westerly heading at 3,500 ft. The camera is oriented to the west, which is in the general direction of Lockhart River. An associated message indicated very low visibility and the pilot was circling while waiting for a break in the weather. No further communication was recorded.
Source: Provided to the ATSB
The Civil Aviation Safety Authority (CASA) issued Air Connect Australia with an Air Operator’s Certificate (AOC) in March 2017 with an expiry date of 31 March 2020. It authorised the certificate holder to operate Cessna C310/340, C404, C402/421 and Raytheon Baron/Travelair aircraft types on charter and aerial work operations. At the time of the accident, CASA was assessing the operator’s application to renew the AOC.
From April 2017, the operator dry-leased VH-OZO from the aircraft owner based at Jandakot Airport, Western Australia. In this arrangement, the aircraft owner was responsible for the continuing airworthiness of the aircraft and the operator managed the operational aspects, such as fuel and flight crew.
The managing director carried out the key roles in the operator’s organisational structure, such as chief pilot and head of aircraft airworthiness and maintenance control. In the 18 months prior to the accident, Air Connect Australia operated one aircraft (VH-OZO) with one pilot additional to the chief pilot (that is, the pilot of the accident flight).
The pilot held a Commercial Pilot Licence (Aeroplane) with an instrument rating and multi-engine aeroplane endorsement. On 7 August 2019, the pilot completed an instrument proficiency check for multi-engine aeroplanes conducted by an independent CASA-approved flight examiner. This was valid until 7 August 2020 and deferred the requirement for a flight review up to August 2021.
Prior to joining the operator in October 2018, the pilot’s recorded total flying time was 2,800 hours. He had been operating as a commercial pilot in remote locations for 5 years, including a total of 3 years based in Arnhem Land, Northern Territory. Between March 2016 and February 2018, he was chief pilot for a charter company that operated Cessna 310 and Piper PA-31 aircraft.
The pilot completed operator induction in October 2018 and received type-specific training in a Cessna 421 from an independent CASA-approved flight examiner. The examiner recalled that the pilot managed the transition to the 400-series Cessna without any problems. Other than the pressurisation system in the C421, the examiner considered it was operationally equivalent to the unpressurised Cessna 404.
Following this, the chief pilot supervised the pilot in command on four flight sectors in VH-OZO and conducted an operator proficiency check (OPC) over two further sectors. The chief pilot noted that the pilot’s planning was satisfactory and operation of the aircraft was above standard. No further OPC was recorded, which was consistent with the operator requirement for an OPC within a 2-year period.
From November 2018 to the accident flight, the pilot was based in Cairns and conducted most of the operator’s charter flights in VH-OZO. During this period, the pilot recorded 70 RNAV (GNSS) approaches to various aerodromes including six at Lockhart River, most recently in October 2019. On one flight, the pilot recorded two RNAV (GNSS) approaches (to Aurukun), which indicates that the pilot conducted a missed approach after the first attempt and landed after a second approach.
In the 2 months prior to the accident flight, the pilot conducted a number of flights (56 sectors). Prior to the day of the accident, his most recent flights were on 18 February 2020. These flights included a RNAV (GNSS) approach and an instrument landing system (ILS) approach.
The pilot had recorded a total of 3,220 hours before the accident flight, including a total of 1,177 hours on multi-engine aircraft with 399 hours on the Cessna 404 aircraft type. Total instrument time was recorded as 148 hours, including 4.5 hours in the 90 days prior to the accident flight.
The pilot’s Class 1 (Commercial Pilot) Medical Certificate was renewed on 14 February 2020 and was valid until 14 February 2021. There were no indications of any significant medical problems in the pilot’s aviation medical records. It was reported that the pilot had been sleeping well in the nights preceding the accident and exercising regularly. He had been on a holiday in the weeks before the accident and was described to be in good health and looking forward to flying again.
Aircraft history and avionics
The aircraft was manufactured by the Cessna Aircraft Company in 1980. It was reported that the aircraft was first operated in Australia before being transferred to Papua New Guinea and registered as P2-ALG. In December 2009, after the aircraft was flown to Australia, a CASA certificate of airworthiness was issued and the aircraft was registered VH-OZO. At that time, the aircraft total time was 28,193 hours.
On arrival into Australia, the aircraft was fitted with aerial geophysical survey equipment and was operated in that configuration until that equipment was removed in March 2012. Concurrently, the avionics were modified in accordance with an engineering order to install new types of avionics and integrate those with existing units. The post-modification avionics, including existing equipment, consisted of:
- Garmin GMA340 audio panel
- Dual Garmin GNS430W GPS/Nav/Com
- Dual Garmin GI-106A CDI Indicator
- Garmin GTX327 Transponder
- Bendix/King KR87 ADF and
- Bendix/King KI-227 Indicator
- Collins HF
- Cessna 400B Navomatic Autopilot
- Bendix non-colour weather radar.
These units were installed at the time of the occurrence except for the transponder, which was replaced by an automatic dependent surveillance-broadcast (ADS-B) compliant unit in April 2017.
The 400B autopilot was one of the standard equipment options for the C404 type. It can provide pitch and roll control with heading and altitude hold (on command). A navigation function provided the autopilot with inputs from an associated CDI instrument, which in this case received data from the number‑1 GNS430W. For a RNAV (GNSS) approach, the pilot could ‘couple’ the autopilot for lateral navigation and manage vertical navigation by adjusting the pitch control or selecting altitude hold.
The aircraft was fitted with the instrumentation required for operations under IFR. These instruments were conventional analogue indicators and reflected the original specifications for the aircraft. It was noted that the second artificial horizon/attitude indicator and altimeter were located on the right side of the co-pilot panel (far side of the instrument panel relative to the pilot).
Source: Provided to the ATSB
The aircraft logbook statement specified that VH-OZO was to be maintained in accordance with the system of maintenance (SOM) developed by the aircraft owner and approved by CASA. The key elements of the SOM were:
- daily inspection in accordance with the Cessna 404 Pilot’s Operating Handbook
- engine and airframe inspections every 100 +/- 10 hours in accordance with the Cessna 404 Progressive Care Program (Operations 1 and 2 plus 3 and 4 completed within 12-month period)
- electrical and instrument inspections every 220 hours or 12 months in accordance with SOM schedules
- IFR avionics inspections every 220 hours or 12 months in accordance with SOM schedules
- Special inspections, Supplemental Inspection Documents, and Corrosion Prevention Control Program as required
- altimeter and pitot-static system inspection and test every 24 months
- maintenance release issue for a period of up to 220 hours or 12 months, whichever occurred first.
Scheduled engine and airframe maintenance was carried out by the CASA-approved maintenance organisation associated with the aircraft owner. While the aircraft was based in Cairns, electrical, instrument, and radio maintenance as well as unscheduled maintenance was contracted to licensed aircraft maintenance engineers.
The most recent maintenance was the scheduled 100-hour inspection based on Operations 3 and 4 of the Cessna 404 Progressive Care Program. This was completed on 16 February 2020 at 31,066 hours total time. A maintenance release was issued with the next scheduled maintenance being the oil/filter change after 50 hours operation and compass swing in July 2020.
Other key maintenance was:
- 19 January 2020 at 31,050 hours: inspection of the electrical, instrument and IFR avionic systems certified as satisfactory
- 29 January 2019 at 30,750 hours: inspection and test of the pitot-static system and check of altimeters certified as satisfactory.
The current maintenance release was not found at the accident site. Operator records showed that the aircraft had been operated for 3.8 hours between maintenance release issue and the accident flight. The operator and aircraft owner both advised that no aircraft defects had been reported.
Garmin GNS 430W
The Garmin GNS 430W is a panel-mounted unit that provided for GPS navigation, instrument landing system (ILS) or VHF omnidirectional radio range (VOR) navigation, and VHF radio communication. It was approved for IFR operations including RNAV (GNSS) approaches and was used in conjunction with a course deviation indicator (CDI) instrument.
Although the ‘W’ designates wide area augmentation system (WAAS) capabilities that allow for GPS approaches with vertical guidance, Australia does not have the associated infrastructure. As such, the GNS 430W was approved to provide distance and track information only for RNAV (GNSS) non-precision approaches.
To use the unit for RNAV (GNSS) approaches, it was a requirement that the NavData card was valid and the approach was loaded from the database. The operator subscribed to the Jeppesen NavData service that provided updates on a monthly basis. It was reported that the pilot updated the NavData card using a laptop computer in the 24 hours prior to the flight, although this is yet to be confirmed by the ATSB.
The GNS 430W has a terrain function that requires a valid 3D GPS position solution and a valid terrain and obstacle database to operate properly. Terrain information is advisory only and can include:
- display of altitudes of terrain and obstructions relative to the aircraft’s altitude
- pop-up terrain alert messages issued when flight conditions meet parameters set within the terrain system software algorithms
- forward looking terrain avoidance alerts in all phases of flight
- premature descent alerting on approach to land (including RNAV approaches).
The ATSB has not yet established if the terrain function was operable and the status of any user and system inhibitions.
Fault detection and exclusion was incorporated into the GNS 430W software to detect satellite failure and exclude failed satellites from usage.
Lockhart River RNAV (GNSS) RWY 30 approach
It was reported that the pilot subscribed to the departure and arrival procedures published by Airservices Australia. A copy of the Lockhart River RNAV (GNSS) RWY 30 approach chart as published by Airservices Australia is shown in Figure 10.
To enable the approach, the pilot loads the approach waypoints and approach tracks from the GPS database. All altitudes specified for the Lockhart River RNAV (GNSS) RWY 30 approach are barometric and are managed by the pilot with reference to the altimeter. In addition to the various minimum safe altitudes for different segments of the approach, the pilot is provided with a distance/altitude scale that provides guidance for the optimum descent angle of 3°.
After the final approach fix LHREF, the pilot is permitted to descend to the MDA provided the aircraft is within tracking tolerances. Further descent is only allowed if the pilot has at least 4,200 m visibility and is able to continue the approach and land on the runway. If the pilot arrives at the missed approach point and is unable to continue the approach to land by visual reference, the pilot is required to conduct a missed approach by initiating a climb to the specified altitude and tracking in accordance with the procedure.
Source: Airservices Australia
The investigation is continuing and will include further review and examination of:
- recorded flight data for the accident flight
- meteorological data at the time of the accident
- recorded flight data as available for selected RNAV (GNSS) approaches conducted by the pilot at Lockhart River and other aerodromes
- regulatory oversight processes for Air Connect Australia
- software version and operation of Garmin GNS 430W units fitted to VH-OZO
- training and checking practices related to RNAV (GNSS) approaches, including missed approaches and subsequent approaches
- occurrences involving RNAV (GNSS) approaches, including at Lockhart River
- existing and potential risk controls for controlled flight into terrain
- human factors considerations
- potential pilot incapacitation risk factors.
Should a critical safety issue be identified during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate and timely safety action can be taken.
A final report will be released at the conclusion of the investigation.
The ATSB acknowledges the significant assistance provided by the Queensland Police Service during the on-site phase of this investigation.
The information contained in this preliminary report 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 preliminary report. As such, no analysis or findings are included in this report.
- Eastern Standard Time (EST) is Coordinated Universal Time (UTC) + 10 hours.
- Visual Meteorological Conditions (VMC): an aviation flight category in which visual flight rules (VFR) flight is permitted – that is, conditions in which pilots have sufficient visibility to fly the aircraft while maintaining visual separation from terrain and other aircraft.
- Instrument flight rules (IFR): a set of regulations that permit the pilot to operate an aircraft to operate in instrument meteorological conditions (IMC), which have much lower weather minimums than VFR. Procedures and training are significantly more complex as a pilot must demonstrate competency in IMC conditions while controlling the aircraft solely by reference to instruments. IFR-capable aircraft have greater equipment and maintenance requirements.
- In the Lockhart River area, VHF contact with air traffic services was not generally available below 4,500 ft. Outside of VHF coverage, pilots communicated with Flightwatch using HF radio.
- QNH: code for the pilot-adjustable barometric pressure subscale of an altimeter. If the accurate QNH value is set on a serviceable altimeter and the aircraft static pressure system is functioning correctly, the altimeter will indicate the height above mean sea level within acceptable tolerances.
- Scattered indicates that cloud is covering between a quarter and a half of the sky at the specified height.
- In aerodrome forecasts and reports, the height datum for cloud is aerodrome elevation.
- TEMPO: a temporary deterioration in the forecast weather conditions, during which significant variation in prevailing conditions are expected to last for periods of between 30 and 60 minutes, and require 60 minutes holding fuel or diversion to an alternate aerodrome.
- Broken indicates that more than half to almost all the sky is covered by cloud at the specified height.
- In aviation meteorological products, time is expressed as coordinated universal time (UTC) and the data is generally expressed in coded terms. For ease of reference, the time has been converted to EST and the data has been decoded.
|Date:||11 March 2020||Investigation status:||Active|
|Time:||0920 AEST||Investigation level:||Defined - click for an explanation of investigation levels|
|Location:||6km SE of Lockhart River Airport||Investigation phase:||Evidence collection|
|State:||Queensland||Occurrence type:||Collision with terrain|
|Release date:||11 June 2020||Occurrence category:||Accident|
|Report status:||Preliminary||Highest injury level:||Fatal|
|Anticipated completion:||2nd Quarter 2021|
|Aircraft manufacturer||Cessna Aircraft Company|
|Aircraft model||404 Titan|
|Operator||Air Connect Australia|
|Type of operation||Charter|
|Damage to aircraft||Destroyed|
|Departure point||Cairns, Queensland|
|Destination||Lockhart River, Queensland|