Two further Qantas aircraft have been hit by safety concerns in the past 24 hours, with one forced to abort a journey from Johannesburg to Sydney.

The incidents bring the total to five in the past two weeks at Qantas, with four planes forced to make forced landings.

Earlier today Qantas spokesman Tom Woodward said a Boeing 747 carrying 171 passengers bound for Sydney turned back to Johannesburg in South Africa after a bird was sucked into an engine shortly after take-off.

The aircraft landed safely, with no reports of injuries.

Separately, a Boeing 717 sustained minor damage to its fuselage when it was struck by lightning during a domestic flight between the Outback cities of Alice Springs and Darwin.

The plane continued safely to its destination of Darwin.

Qantas Concerns

Four Qantas jumbos have turned back because of various problems since a November 4th engine blow-out on a Qantas Airbus A380 near Singapore triggered a global safety review of the plane.

Rolls Royce has since identified a fault with its Trent 900 engine which powers the aircraft.

Singapore Airlines and Lufthansa have all been affected by the problem, with both temporarily grounding aircraft for safety inspections.

The incident heaped further attention on Qantas, which has one of the best safety records in the industry having never had a fatal crash.

The day after the A380 problem, a Qantas Boeing 747 bound for Sydney turned around and landed safely in Singapore after an engine caught fire minutes after take-off.

Last Friday, a Boeing 767 turned back on a domestic flight in Australia after pilots detected abnormal vibrations in the engines.