North America’s wildfire season is getting stronger and longer every year. Take, for example, the massive conflagration currently raging through the Canadian oil city of Fort McMurray in Alberta, which has burned over 500,000 acres and lead to the evacuation of 80,000 people since it started on May 1. 

One response to these bigger fires is to build bigger, faster firefighting tools. And last week, a young Colorado Springs-based company called Global SuperTanker Services debuted the biggest, fastest one yet: a converted Boeing 747-400 equipped with a tank that can hold 19,600 gallons of fire retardant—nearly double the size of the tank in the next largest air tanker. The plane named the Spirit of John Muir, can cruise at speeds up to 600 miles per hour for as far as 4,000 nautical miles and get to any fire in the western U.S. in a few hours. 

The aircraft, which cost more than $10 million to purchase an outfit, made its first successful test drop in early May in Arizona, then conducted a flyby performance in front of crowds last week in Colorado Springs. It’s expected to receive certification soon and begin operation in the field by late June. It’s a larger, modernized version of a plane originally designed by Oregon’s now-defunct Evergreen Aviation. (Global SuperTanker Services purchased the old plane’s patents, systems, and certificates.) “People are living closer and closer to forested areas and now a fire that would have burned itself out years ago will burn a thousand homes,” says Jim Wheeler, president, and CEO of Global SuperTanker Services, which has been working on the air tanker since September. “There’s now an even bigger need to arrest these fires.” 

Sounds impressive. But there’s no guarantee it’ll do much to reduce the threat of wildfires near urban areas.  

Timothy Ingalsbee, a former wildland firefighter for the U.S. Forest Service and the co-director of the Association for Fire Ecology, says that chemical retardants—which are designed to slow the rate of fire spread, not extinguish it— aren’t very ecologically friendly, and not that effective on large, raging burns. Plus they’re wildly expensive to drop from an airplane.

The U.S. Forest Service (which does not currently have a contract with Global SuperTanker’s plane), has spent an increasing amount of money over the last five years on aerial firefighting solutions. In 2015, the agency paid $140 million for commercial air tanker services, up from $56 million in 2011. For whoever hires these planes, be it the Forest Service or a different government fire agency (depending on where the fire is burning), it can cost up to $28,000 per day just to have them on standby, and hourly rates for flight time are as high as $10,000. That’s not including the costs for the pilots and retardant.

“It seems that a majority in Congress and high-level Forest Service officials are dead-set on buying into the next generation fleet of air tankers regardless of the emerging evidence that they are largely ineffective and hugely expensive,” Ingalsbee says. “The cost [of airtankers] is a huge concern, and in my opinion, this will be a big boondoggle that will shower taxpayer money on private contractors with no real benefit to the public or the land.”

Many critics, including Ingalsbee, point out that giant tankers dropping water or retardant make for great photos and video clips, but aren’t worth the cost.  

Wheeler, for his part, responds that its oversized air tanker isn’t for every fire. “We’re not the smallest or the cheapest,” he says. “We’re just one tool in the toolbox—we just happen to be the largest, fastest tool. We’re not the answer to every situation and we don’t see ourselves as that.”