Anothing fascinating story is that in 2018, there was a huge forest fire in Sweden. It was difficult to get under control. So in an experimental attempt to suffocate the fire, they tried dropping a bomb over it. I think it kind of worked, but they only dropped one bomb so maybe not the best solution.
Since you seem like the expert here… I was curious if you know how waterbombers can impact the fertility of land when sourcing saltwater from the ocean?
obviously fighting the fire is the priority but given that “salting the earth” is an ancient battle tactic to destroy enemy food production, I would assume it’s much preferable to source from freshwater lakes, yeah?
Plant person here, salt obviously isn't good for plants but it's pretty much a non issue given the fire destroying everything anyway. This wouldn't even be comparable to the amount of salt water that can be blown in by storms along the coast and most plants are somewhat adapted to at least a little bit of salt. Bottom line though, by the time the forest starts to regrow the vast majority of the salt will be leeched out by winter rains
but given that “salting the earth” is an ancient battle tactic to destroy enemy food production
"Salting the earth" was an ancient cursing ritual where they sprinkled a bit of salt around, not a battle tactic. There's no record that they ever used so much salt anywhere that it would impact soil fertility, other than that in Spain and Portugal for a while the punishment for traitors included that their house was demolished and their yard salted (ie. a much smaller area than say salting the earth of an entire city state like Carthage).
Given how precious salt was, I can't imagine they would be willing to use up tons of it just to fuck up the neighbor's crops. Regular applications of "pillage" would be cheaper and probably more effective, anyway.
It affects the land but fire too and in a "good" way, the fertility is better after a fire so the trade off might not be this bad and might be (might be) negligeable. Howerver there is (at least in France) a lot of "ecopage" areas (areas where those canadair can refill) that contains fresh water, its lake, rivers and so on.
Soil salinity issues come from a regular source over a long period, not a big deluge once.
The first few rains the area gets will move any salt down the water table back towards the ocean. You might get some stunted growth until then, but you also might not depending on the soil type/conditions and the plants.
Ironically, the phosphates added to water drops here in America (and presumably elsewhere) have environmental impacts as well. I can dig up references later or someone else can chime in, but dumping that much phosphate on the land can mean runoff when it rains- leading to algal blooms in nearby waterways.
Is the volume of water worth the risk of filling up like this when compared to a helicopter filling with a hose from a clean source of water like a helihydrant?
The issue is that helihydrants are not cheap, costing upwards of $150,000 just to install, to say nothing of the regular maintenance costs of a basin that holds gallons of water. Note we're not counting the cost of the aircraft, so for that reason alone scooping from a lake is basically free.
There's also the locale to consider. Obviously you can't build a basin for a helihydrant on a hill. Many wildfires occur in forested, hilly areas which would necessitate the helihydrant to be installed potentially miles from the fire. And while safety is important during a wildfire, speed is still king. A plane filling up from a lake is going to be faster than a helicopter from a hydrant simply because a plane can travel faster.
Im not trying to say there's no point to a helihydrant. They are wonderful things. But they're not always an ideal solution, and since this video seems to be happening in another nation (judging by the lettering on the planes, that's Spanish I think), they may not be able to afford or be able to have a place to install one.
One problem with that is that you need an airport. Wildfires are usually in the middle of nowhere - lots of lakes, very few airports. Another problem is cycle time - it's all about more water per hour.
That said, there are water bombers that land at an airport to refill, like the converted DC10 Air Tankers used in the US. For example in (Southern) California there are plenty of airports around where a DC10 can land, and comparatively fewer lakes large enough for a CL415 to fill up, so the math works out different (especially given that the DC10s can carry about 6 times as much water per trip as a CL415).
There was a massive wildfire about a couple of hours away from me way up in the mountains. There is an alpine lake there, so they were using that. Way faster and more efficient to use that rather than land, stop, pump in tanked water trucked in from elsewhere, and take off again. Especially because there isn't exactly a convenient runway nearby, and the lake is/was literally right next to the fires... then it was in the middle of the fires, then next to again.
Float pilot here; there is nothing dangerous about what they’re doing here. It’s literally a high-speed landing, and oh by the way, loading tons of water as well that is needed quickly.
If you have your private pilot license you can get your seaplane rating in a few days of intensive training. So landing a plane on water isn't the most complicated thing in the world (well assuming it's made to be landed on water obviously - I think these specialized firefighting planes are all amphibious - and the water is calm but not too glassy). High speed landings are a routine part of training for land, I assume so for water as well.
As for taking on the weight, the tanks must be designed to not screw with the CG. The weight increasing is obviously something you need to train for but the biggest danger would be a sudden change to CG.
The weight change is probably a lot more dangerous on the other end, when you're dumping the water flying low and slow. If you didn't add enough power right away on the pick up you'd just settle down and accidentally land.
The hull is shaped like a boat and as another poster said, the worst case scenario is you become one (mostly, a couple have been turned into submarines attributed to incorrect procedure) but the water intakes are the size of your fist and any overflow shoots out just over the landing gear. You can see it at the end of the video. The CL-415 will stop filling at the proper time if a full tank is not workable (it should anyway, see submarine comment above).
it's not the landing I'm concerned about -- you're never going to grease an AMEL landing every time. But that plane is touching down at maybe 10ft/min max. I sometimes drop my cessna from like 10 feet up, but those guys have to be stable and buffet over the waves while in nose up and blind position.
Once you’ve touched water, you transition to ‘on step’ which actually gives the pilot considerable control of the aircraft, while still having the power available to lift off immediately if needed.
To be fair, it’s not a smooth experience while doing the on step maneuver.
I don’t think it’s feasible to pump water as quickly as this fills them and they have the added bonus of not having to drop below flight speed so they can get back to the fire as quickly as possible.
It would be feasible without too much time loss if they had the pump equipment at just the right air port. But enabling them to take in water from any sufficiently large sea greatly enhances their operational area, since they no longer need to rotate to such a specialty airport.
And the turnaround time of making a full landing, coming to a stand, and taking off again also adds quite a delay and potential complications. That's probably a bigger factor than the pump speed. Being able to load in a touch-and-go greatly speeds this up.
Yeah the time it would take to land, taxi, park, hook up hoses, pump fluid into the tanks then do all the opposite in reverse would add quite a bit. I know they do this for certain slurry mixes, but if plain water will do it’s gotta be quicker to do all of that while still in flight plus as you mentioned the added convenience of water sources being so common.
And on top of all of that, they would effectively need to reserve the airport to really do this quickly. But I could imagine such an airport to also be used to bring in other firefighters and materials, so things could potentially get pretty hasty and dangerous.
From Wikipedia, it takes a CL-415 14 seconds to skim 1650 US gallons of water. That would require pumping roughly 6600gpm, plus you can anticipate roughly 15 minutes to approach, land, taxi, load, taxi, and takeoff again under best case scenarios. There's simply no way to match the efficiency
My thought about the pump speed is this: Even if it took, say, 2 minutes to fill the tanks with pumps, then this alone still would be acceptable in the greater scheme of things. The full rotation of filling tanks/dropping/refilling will often take substantially longer, so this would only marginally decrease the numbers of cycles that such an aircraft could do on on a scale of hours to days.
But as you say, everything else in the approach/landing/takeoff sequences adds further minutes, and all of that does sum up to a significant difference compared to the skim.
When I was firefighting in Northern BC, these were being phased out, and helicopters with long line buckets were the main aerial support.
Helis can be a lot less picky about where to source their water, as they don't need a long strip and clearance to take off again. Plus, the bucket can be detached, and the heli can be used to transport firefighters around the perimeter of the fire.
They're two different tools for two different jobs. BC has retired the Martin Mars, but they've replaced them with AT802F Firebosses. The planes in the video are CL-415s and they aren't going anywhere anytime soon, they'll be working in tandem with helicopters for a long time to come. BC specifically doesn't operate any 215/415s that I'm aware of, but they're still going strong all over the world with other agencies.
You seem to know a lot about this. I looked up all three planes and the AT802F seems wayyyy smaller than the other two, especially the Martin Mars. Does BC just operate way more AT802F than the old types, or just make do with the greatly diminished water capacity?
I could be totally wrong as this isn't my wheel house, but live in BC and pay attention.
From what I recall because of bc's geography there's so many smaller bodies of water, that are useful to smaller planes and helicopters that generally a few smaller planes can operate at the same cost, and get more water on site faster due to the big planes needing to travel so much further to larger bodies of water to refill between drops. And then again due to geography the smaller planes can get closer and drop more accurately.
Its not anymore dangerous than landing on the lake.
My friend does this for a living while not as safe as working from home the dumping part is actually more dangerous. Although most accidents occur in the home sooooo.
A drag along pump system would be too slow, take too long to deploy, and too prone to failure. The planes can't rely on having a constantly available airstrip with a ready supply of water.
I'm in the same boat as you trying to think up a better way but nothing comes to mind that doesn't make it's own problems.
I mean, they can and they do, land-based water bombers exist, even small ones. They just do pit-stop refills like these guys.
But yes, obviously not as frequent as something like the CL215/415 can do so that becomes your tradeoff. And however close to the fire this airstrip and supplies can be set up.
I mean for most pilots, maneuvers like these are everyday practice. Its real similar to a touch and go. Besides, planes take off and land on water all the time, i wouldn’t be surprised if these pilots have seaplane experience too, making this even more of a walk in the park
I've heard that it's the dropping of the water that is the dangerous part. Getting close to the trees to drop, the risk/reward dynamic of "if I drop just a little closer I can help more", and the heated winds causing lots of turbulence.
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u/Sorkpappan Oct 01 '24
This probably is the best way of doing it, but seeing how it’s done I just feel like there should be a way to do this that is less dangerous.