"Good Afternoon, This Is Your Captain Speaking, You May Be Feeling Some Slight Turbulence As Our Automatic Pilot Has Been Disabled By Military Radio Transmissions...."

It's weird and unnerving enough that it's happened once, that we know of, now it's happened again, the second time in twelve weeks :

A malfunction has forced a Qantas jet to return to Perth, prompting concerns for the second time in three months that interference from a defence station in northwestern Australia may be to blame for a mid-air drama on the national carrier.

Qantas flight 71 was on route to Singapore with 277 passengers about 8.30am last Saturday when it had to return to Perth after the jet's autopilot disconnected because of a problem with a unit that supplies key information to flight control computers.

Aircraft engineer Peter Marosszeky said yesterday it was possible that interference from radio transmitters at the station could have caused the malfunction in both incidents.

Apparently, the radio transmisison signals from the Exmouth defence station can travel 260 nautical miles. A few more details.

"These signals are supposed to travel around the world to reach submarines in the water and naval vessels, so they are very powerful..."

The Defence Department would not comment yesterday.

What could they possibly say? Err, whoops.