All aircraft face condensation. Passive moisture control measures, such as isolation of blankets and drainage of condensate water, have improved. But for many airlines those are not efficient enough as aircraft spend less hours on ground and more hours in the sky. Furtermore, aircraft fit more seats in the same fuselage and strive to operate with a ‘high-load-factor’ business model. Many airlines also have outsourced their aircraft maintenance (i.e. less knowledge of actual conditions).
Bottom-line is that passive moisture control measure are no longer sufficient. Although it is not always as obvious as shown in the picture. Water accumulation can be distributed and hard to discover.
The anti-condensation protection system has been tested in several airlines trials, including weighing aircraft before and after installation.
In one trial, three Airbus A320s conducted did a 18 months evaluation. The aircraft were weighed before the trial and then weighed again after a few months; recording an average weight decreased with approx. 200 kg. The systems were turned-off and flight tests resumed. The aircraft then increased on average with approx. 200kg back again to pre-test weight. The six month on-off was repeated with the same encouraging results.
The trial not only focused on measuring the weight saving benefits but also monitored components included: antennas, sensors & computers. The trial resulted in a 40 % reduction of unscheduled component change per 1,000 flight hours.
Apollo did a 12 months evaluation trial in one of its Airbus A321 aircraft. The weight reduction accounted to 284kg.
Germanwings performed a 12 months A319 evaluation trial. Resulting in a 140kg net weight saving,