A “rare and dangerous” updraft from the Washburn Fire in Yosemite National Park last weekend had tree branches and other debris sucked high enough into the sky that they rained down on firefighting tanker airplanes dropping water on the blaze, according to an article shared by the San Francisco Chronicle.
Tree branches do not normally rain down on airplanes. But it happened at the Washburn Fire in Yosemite.
Twice over the weekend, pilots reported stuff falling from the sky as they flew over to drop water on the blaze.https://t.co/wcbcIcso5j
— San Francisco Chronicle (@sfchronicle) July 11, 2022
Britt Coulson, a contractor with Coulson Aviation in British Columbia, told The Chronicle on Monday that twice over the weekend, pilots reported “stuff” falling from the sky as they flew over to drop water on the wildfire. In the first occurrence on Friday, an object actually hit the fuselage of a tanker. Then on Saturday, a large branch sailed over the top of another firefighting airplane, almost hitting it. Apparently, this happened because of convection, which in the case of a fire is caused when rising hot air is replaced by cooler air rushing in at ground level. The Chronicle reports that the force from this convection can be so great that it can literally carry debris from the ground up into the sky by means that can only be described as a “reverse tornado.”
This has happened before. During a wildfire in Southern California in 2003, the windshields on six air tankers were cracked from sheets of plywood that were reportedly flying at 1,500 feet because of the fire-generated convection, according to an article published in the journal Wildfire Today by writer Bill Gabbert. It’s not only those on the ground fighting the wildfire taking on all of the risk—it’s the pilots dropping water from above as well.