Airbus recently tested a roll-on/roll-off system to enable an Airbus A400M to drop water on a wildland fire; they say it can hold up to “20 tonnes of water.” A video shot at the test site in Spain showed the water exiting the aircraft out the rear cargo ramp.
Airbus provided some information about the system being tested:
The Airbus firefighting solution created for the A400M is a roll-on/roll-off (RORO) kit that requires no modification to the aircraft and therefore is interchangeable to any aircraft in the A400M fleet. The water is stored in a fixed tank in the cargo hold, and retained by two independent doors. These doors are connected to two flood pipes, so when the discharge is triggered, the water is expelled through two sections at the end of the ramp. The introduction of this RORO solution allows a rapid reaction to unforeseen fires and reconfiguration of the aircraft to any of its other roles.
It was tested at a minimum operating height of 150ft, flight speeds as low as 125 knots, and drops involving up to 20 tonnes of water in less than 10 seconds. Airbus also plans to test the system while flying at night.
Airbus’ video below describes the system.
The system is reminiscent of the Modular Airborne FireFighting System, MAFFS Generation 1 developed in the United States. After being rolled into a C-130, it dispensed retardant out the open cargo ramp. Due to retardant coming back into the C-130 during a drop and coating many parts of the aircraft, the next version, Generation 2, pumps the retardant out a port on the sealed left side troop door.
We have contacted Airbus for more details, asking how the water is forced out of the tank, if it is by compressed air, a pump, or simply gravity.
Below are more still images from the Airbus video.
In November, 2021 we wrote about a company in France that is designing a retardant delivery system for an Airbus A330. With variants of the original aircraft capable of transporting 247 to 400 passengers, Kepplair Evolution’s plans call for the A330 air tanker to be able to carry up to 9,000 gallons, just shy of the 9,400-gallon capacity of a DC-10 very large air tanker.
In collaboration with Pr Dominique Legendre of the Toulouse institute of fluid mechanics (IMFT), Kepplair has built a 1/3 scale prototype of their KIOS system which they say validated the concept of the patent by specifying the control to be implemented to guarantee a constant flow. As part of the maturation program managed by IMFT and Toulouse Tech Transfer, further tests are being carried out to confirm the scaling up.