Last Thursday, Mwangi also failed to identify the mysterious engineer under cross-examination and it had been expected that he would have established his identity and qualifications before coming up for Monday’s hearings.
The inquiry heard that several weeks before the copter crash, Aristides had reportedly attempted to repair faults in the engine control system after warning lights indicated malfunction, but failed to diagnose the fault after several attempts.
According to Mwangi, Aristides called in the mysterious engineer who services planes at a nearby facility in Wilson Airport. The mystery man removed the FADEC (or the Full Authority Digital Engine Control ) that controls engine performance and replaced it with another bought in South Africa.
“Whatever the gentleman did was under the supervision of Aristide who had the overall responsibility of servicing and repairing the plane. I didn’t have any reason to suspect anything wrong,” added Mwangi.
He revealed that despite that replacement of the FADEC, another warning light indicated a failure in the Engine Data Recorder (EDR) that captures information on engine activity.
When the police engineer contacted Eurocopter South Africa about the EDR failure, they were assured in an email message that the mechanism did not directly affect the safety of the helicopter, and that they could continue flying for at least 200 more hours in spite of the defect, said Mwangi.
It also emerged on Monday that the ill-fated plane had only one Primary Flight Display (PFD)instead of two as agreed in the tender documents before the purchase.
PFDs help in controlling various crucial aspects of flight including altitude and vertical speed. Each unit is placed in the pilot and copilot’s compartment. .
Lawyer Fred Ngatia, representing the Saitoti family suggested the lack of the PFD on the copilot side, might have hampered the safe operation of the helicopter. He said the supply of one PFD violated the Ministerial Tender Committee that procured the helicopter.
Mwangi said that during the pre-shipment inspection in South Africa in late November last year, he inquired about the absence of the second PFD, but was told by Eurocopter officials that Police Airwing Commandant Rodgers Mbithi approved one.
“I asked for the second PFD and I was informed that the cockpit layout with one PFD was already approved. I asked no further questions,” he said.