World premiere at Austrian Technical Services: in our first redblog story, we took a look behind the scenes at the mega-refit of our new long-haul fleet. Now we want to give you a few more thrilling facts and figures about the refit of the B777 in Vienna: why is the refit of the fleet a world first, for instance? How many technical drawings need to be produced for the refit? And how many kilograms of cabling are there hidden away in a Boeing 777? We spoke to the technicians responsible for the mega-refit.
1. A world first
The refit of the Boeing 777 is a world first: this is the first time ever an airline has installed the seats and IFE in this configuration on this type of aircraft. The Austrian Technical Services team now has cabin refit work to do on four B777 aircraft. But the four aircraft are not identical; they are laid out in three different configurations. “That means each aircraft is like starting from scratch for us,” Oliver Trinkaus, Team Leader Base Maintenance and Coordination C-Check explains. “We need to re-measure and re-calculate our work, down to the last detail, on each aircraft. Because our passengers will see the result the moment they board.”
2. The specification: 1,400 drawings per aircraft
The technicians work according to drawings when converting the B777 – around 1,400 of them per aircraft. “We have a permanent control on site: The so-called ‘Designated Engineering Representative’ (DER) checks every drawing and whether everything is being installed as defined in the drawing, “Walter Beuk, Technical Project Manager from Component & Airframe Engineering, explains. The reality sometimes looks different, of course. “Some parts don’t fit, for example, because a hole might be in the wrong place,” Walter Beuk says. “It only needs to be a millimetre out. In this case, you have to write a so-called deviation, and have it approved by the American authorities. That takes several days. And during this time, you can’t keep working on this point, and have to re-plan your work instead.”
3. Cable salad: 150 kilograms of cabling
The cabin refit begins with the cabin being completely emptied, as the seats, cabling, IFE compartment and forward galley are all dismantled. “This takes about a week and a half,” Walter Beuk says. When taking apart the old Inflight Entertainment System, vast amounts of cables are removed from the aircraft, or about 150 kilos of cables per aircraft. These can no longer be used, and are disposed of. The old seats find a new home, meanwhile; after being temporarily warehoused after the aircraft is dismantled, they are sold on.
4. The aircraft scales
“After the entire refit is finished, the B777 has to be newly weighed, because the refit has an influence on the distribution of weight, of course. So you have to define the new centre of gravity of the aircraft,” Herbert Huemann, Team Leader Base Maintenance and responsible for the electrics, explains.
So how do you weigh a Boeing 777? Here’s how it works: the B777 is pulled onto weighing plates by a tractor.
On the weighing plates, there are so-called piezoelectric strain gauges. These are crystals which react to pressure, and when doing so give off an electrical charge. This charge makes it possible to calculate the weight of the B777.
Electronic bathroom scales are based on the same principle, by the way. A total of 2 – 3 such measurements are carried out on each aircraft in this way, to exclude the possibility of errors in the measurement.
5.Final check: the test flight
Once the work in the cabin has been completed, there’s only the final check still to go: in a test phase lasting around a week, various functional and load tests are carried out. Finally, the aircraft has to pass a test flight, in which detailed tests are carried out according to a check programme while the aircraft is actually in the air. Do all the seats work? Do all the overhead bins open and close? Can 40 laptops be operated at the same time? A root and branch test flight, therefore, which takes between six and eight hours. Pilots who take a test flight of this sort require special training to do so. The final test is always the attainment of authorisation to fly from both the American (FAA) and European (EASA) aviation authorities.
Our technicians have to keep to a very tight schedule, therefore, and are faced with new challenges every day. We hope you will like our new long-haul cabins, and look forward to welcoming you on board! To get a brief taster of the new look, click here for another glimpse of the images of the refit of the Boeing 777 in Vienna. Watch this space: next time we’ll be showing you exclusive pictures of the refit of the Boeing 767 in Shannon. 🙂