Rudolf Gaiseb
The accident in which a Robinson r44 Raven plane crashed last year, killing the pilot and an apprentice maintenance engineer, was due to a motor stall and the main rotor blade striking the tailcone.
Pilot Jacques Jacobs and apprentice maintenance engineer Dirk von Weitz died in the fatal crash on 17 July 2023.
Von Weitz did not attend the Robinson Helicopter company’s maintenance course, but had company approval from the aircraft maintenance organisation (AMO).
This is contained in the investigation report released by the Directorate of Aircraft Accident and Incident Investigations (DAAII).
A preliminary report released in August last year revealed that the pilot had a valid Namibian helicopter commercial pilot licence, but the aircraft did not have an airworthiness certificate.
“The helicopter did not have a valid certificate of airworthiness for South Africa or Namibia. Its South African Certificate of Airworthiness expired on 31 December 2018. The engine that was installed on the helicopter (engine of V5-HJL) was not logged in the engine or airframe logbooks.
The registration number, V5-HGG, which was pasted on the helicopter, was a Namibian registration, but the helicopter was never registered in Namibia. However, when the helicopter arrived in Namibia (February 2022), the AMO applied for the registration V5-HGG to be reserved in terms of NAMCAR 47.04.3,” reads part of the report.
Registration
Lead investigator Ben Engelbrecht stated that “the records showed that the regulator did reserve registration V5-HGG, but the process was never completed. The reservation period, which is six months, lapsed. The helicopter was, therefore, never registered in Namibia.”
At the time of the accident, the helicopter was still legally registered in South Africa under South African registration ZS-HLG. The helicopter likewise did not have a valid Special (Test) Flight Permit to perform the test fights.
Furthermore, the Namibia Civil Aviation Authority (NCAA) issued the certificate letter of no objection for the importation of the helicopter from South Africa on 23 February 2022.
The e-mail communication between the NCAA and the AMO, seen by the investigators, showed that the NCAA tried to stop the importation after receiving information that the helicopter was not airworthy, and that it required a 12-year inspection.
However, there is no evidence that the NCAA cancelled the certificate letter, or informed their South African counterparts they were objecting to the importation of the helicopter.
“When the ‘no objection certificate’ [letter] was issued, the regulator did not follow their own process to obtain the helicopter airworthiness information from their counterpart in South Africa. The regulator also did not question the AMO where the helicopter was when they applied for the reservation of the registration (V5-HGG),” Engelbrecht noted.
Efforts to solicit comment from NCAA boss Toska Sem yielded no positive outcome, as her phone was unreachable.
Investigation
During their inquiry, the investigators found counterfeit certificates and permits, posing a significant risk to aviation safety, especially in Namibia.
They strongly advised the NCAA to upgrade their certificates, permits and licences by adopting stringent security features.
“The current licensing and certification system lacks adequate security features, making it susceptible to forgery and unauthorised replication. Strengthening the certification process is critical to maintaining high safety standards, and protecting the integrity of Namibia’s aviation sector,” Engelbrecht continued.
“There is a critical need to enhance the surveillance and monitoring of aircraft operators in Namibia, especially at outside stations. Operators know when to expect inspections, and prepare for them. Strengthening the surveillance programme, especially spot/unannounced inspections, will ensure that operators are always in compliance with all safety regulations and standards,” he said.
The investigators then called for the integration of modern security features into permits, certificates and licences, specifically holographic seals, to prevent unauthorised duplication or watermarks embedded within the document to verify authenticity.
The incident
On the fateful Monday afternoon of 17 July 2023 at around 15h35, a Robinson R44 helicopter with registration ZS-HLG left the Swakopmund airfield to perform a maintenance test flight.
No flight plan was filed for the local maintenance test flight, as it was not required by regulations.
The purpose of the flight was to conduct final rotor balancing, and to execute auto-rotations.
On board the helicopter was the pilot and apprentice maintenance engineer.
The helicopter was brought into Namibia from South Africa by a local operator on a trailer in February 2022, and transported to the local AMO for maintenance inspection and certification.
The helicopter and engine required a 12-year inspection.
After all maintenance work on the helicopter was complete, the test flights started.
The first test flight was on 13 July 2023.
Another test flight was conducted on 14 July 2023.
A fixed-wing pilot who had just landed at Swakopmund airfield was asked by the pilot-in-command (PIC) to join them on the test flight.
The fixed-wing pilot sat in the right back seat, behind the PIC, while the apprentice engineer occupied the left front seat.
The fixed-wing pilot described the flight as very “bouncy” and vibrating a lot.
The fixed-wing pilot observed that the PIC apologised for the vibrations, as they took a short scenic flight over the dune belt.
The fixed-wing pilot made four short videos, which were shared with the investigators during the flight, and the vibrations can clearly be seen on the control stick, and the legs of the pilot and apprentice engineer.
After landing and shutdown, the apprentice engineer said he would add another 120 grammes to the main rotor blades to curt the vibrations.
The fixed-wing pilot stated that the PIC told him that he did not understand why the vibrations had become worse.
According to the maintenance schedule, the fatal Monday afternoon flight was the last test flight, which required rotor balancing, and to execute auto-rotations.
The pilot followed regulations not to do the maintenance test flight over populated areas, and proceeded to an open area east of the Swakopmund airfield.
During the auto-rotation, one of the main rotor blades hit the tailcone, causing it to detach from the main fuselage.
Witnesses
Witnesses heard a loud bang, and saw the helicopter spiralling down to the ground.
The helicopter hit the ground with the left side at a high speed.
The tailcone was found 158 metres from the main wreckage.
The accident was not survivable.
Eyewitnesses, the local flying school crew, and the AMO crew rushed to the crash site.
The police, the ambulance, and the Swakopmund Municipal Fire Brigade were called to the scene.
The pilot and the apprentice engineer onboard the helicopter had died in the crash.