Dear Captain Lim,
I recently read that airlines have the option to not install fuel dump mechanisms on their A330 aircraft.
Isn't that dangerous? I mean, say an A330 takes off with way more than the maximum landing weight, suffers a critical failure after takeoff and have to turn around immediately. How would it get rid of the excess weight in order to make a safe landing quickly?
This article shows what I mean: http://www.news.com.au/travel/news/qantas-jet-makes-emergency-landing-in-sydney/story-e6frfq80-1225831858246
What if the Qantas jet had a gear problem and an engine malfunction? I doubt that it would have been able to circle for all that period.
Thank you for your time
And compliments on your magnificent site
It is not dangerous if the A330 does not have fuel dumping facilities. Most airlines prefer not to have this option to save cost as this aircraft is generally a medium-haul plane. Unlike the long-haul A340 planes which have a higher take off weight, fuel dumping facilities would be needed to prevent landing at excessive weight.
Although most Airbuses have a maximum landing weight limitation, overweight landing is permitted in case of a dire emergency such as a fire on take off. Other emergency such as a landing gear unable to retract is not a critical event. This allows the captain to make a discretion to land overweight or to burn off the extra fuel if the jettisoning mechanism is not available to do the job faster. In such a case, the captain may decide just to stay, say two more hours in the air to burn off the fuel rather than risking an overweight landing.
Pilots avoid landing overweight as this may cause the aircraft to be grounded for a maintenance check before being released for flight again. This may cause some flight delays. Weight this against a 2-hour in the air to enable the plane to burn off around 24 tons of fuel would be a better choice in some situation.
If it were a critical emergency, the pilot would land overweight anyway without any problem. So the issue is one mainly about economics.
Fuel Dumping on a Boeing 777