how does a water bomber for fighting forest fires ingest all that water? Do the pilots have to keep adding more power as the plane’s weight changes to prevent it from dropping into the water?
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Forward speed across the water forces water into the tanks. Thayer can also be filled with water or retardant on the ground via a hose adapter.
Yes, power must be increased to maintain airspeed as weight increases.
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Cool I get to answer one of these. There’s two main scoopers (we don’t call them water bombers) used in the US. AT-802 “Fireboss” and CL-415 (and some CL-215Ts). Both scoop water using the speed across the water to fill the tanks. The actual opening in the float systems is actually pretty small, about 4×8 inches on the 415, which are opened and closed from the cockpit.
While both aircraft can be loaded on the ground, they rarely do, especially with retardant. The fire bosses are just AT-802s (SEATs or Single Engine Air Tankers) used for firefighting with floats attached. With the extra weight they’re slower and can’t hold as much retardant as a SEAT without the floats. Also you’d have to rinse out the tank to go back to scooping. Scoopers work very well when there’s a water source much closer to the fire then an airport where they can get retardant, also retardant and water are used differently on a fire. This is why you don’t see many scoopers used in places like central Nevada since there’s no water sources.
As for how things are loaded while on the ground. All firefighting aircraft and bases that support them have a 3in cam-lock system where a 3in hose is connected to the aircraft and water/retardant is loaded at anywhere from 250 gallons to 500 gallons a min.
Canadair planes can float even when full of water.
Water will be ingested because the speed of the aircraft on will force the water in its scoop, pretty much like a [water trough](https://en.m.wikipedia.org/wiki/Water_trough) for old steam trains.
Because the plane is also a boat, when scooping, the pilots will compensate for the extra water weight and maintain ground speed, not by fear of sinking but to have enough speed to keep flying.
Check this (https://youtu.be/fuLk5hXMRZY?si=u02eB1wjt-vXHkKp), it explains things pretty well
Not exactly what you asked, but for helicopters, we have a big flexible bag that hangs from the bottom of the cargo hook. You hover over the water then slowly lower the bucket until it submerges and fills up. Once it’s full, slowly add power until the bucket breaks the surface completely. Flying to the fire is hard because you have a ton of weight dangling around and if you’re not careful you can cause it to swing really bad and potentially endanger the aircraft. When you get to the fire you fly slowly on whatever heading required and release the bottom of the bucket so the water streams out. You have to be ready to drop a ton of power at the same time because you suddenly weigh x thousand of pounds less.
Don’t know anything about fires or airplanes. But I know a bit about physics.
The additional weight of the water in the plane requires the exact energy required to scoop it up and raise it up to whatever height the plane wishes to raise it to. These are called kinetic and potential gravitational energies.
Due to conservation of energy, the planes engines must supply this energy (by burning fuel).
Conversely, when the plane drops the water, it becomes lighter and there is less potential energy so the pilots would have to apply progressively less thrust.
I never gave it much thought but piloting one of those must be significantly more difficult than a traditionally loaded aircraft.
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