The little airplane flew into a thermal and began to rise dramatically. “Woo hoo!” said Lee, chortling. He moved the controls to circle the plane and keep it in the rising column of air while backing off of the throttle simultaneously. Jake had the other controller and was ‘flying the camera.’ Their drone was setup to use one radio to control the aircraft and another to operate the camera. This separation made for excellent video because each ‘pilot’ could concentrate on a single function.
The drone was a foamie; an airplane made out of shaped urethane foam. It had a six foot wingspan reinforced with tubular carbon fiber spars. It carried a computer driven flight control system that used a series of sensors to determine the aircraft’s positional situation in all three axis’: pitch, yaw and roll. It could also determine it’s position with GPS, which also gave speed information in concert with pressure sensors that together returned accurate forward speed and rate of climb or descent. The computer knew the minimum and maximum speeds of the plane; the minimum speed it could travel while still maintaining lift across the wings, and the maximum speed the aircraft could travel without suffering structural damage. The computer also controlled the G forces on the aircraft to the abrupt maneuvers wouldn’t break the wings off. Much like modern commercial airliners and military aircraft, the little aircraft was fly-by-wire. The pilot used controls to direct the craft and the computer executed those commands with safety and stability. Mounted in a clear belly dome was a Digital Single Lens Reflex camera on a gimbal. The photographer could rotate and pitch the camera, change exposure and switch between video and single shot photos. Between the ability to manipulate the aircraft and the camera, the aircraft was able to shoot startlingly crisp and clear images. Using yet a third radio, the perspective of the camera lens was sent down to the photographer, a kind of video viewfinder.
The last decade had brought tremendous miniaturization and development that made such advanced technology economically feasible for commercial and amateur photographers. Prior times only the military could have such capability at its fingertips. The military still holds a significant lead in aerial photography, but civilian requirements neither need or want that edge. The technology available is more than sufficient for the missions of civil flight.
The aircraft had achieved an altitude of 14,000 feet. In actuality though, it was merely three hundred feet above the mountain that was today’s photography subject. They were doing an inventory of raptor nests; specifically counting the nests of the shrinking population of American Condors near Miday Mountain just north of the Inyo National Forest on contract to the Department of Natural Resources. The area was steep and treacherous and the use of a drone made easy a task that would be both exhausting and dangerous if performed by individuals. Helicopters couldn’t be used because of their downwash, whose hurricane level winds would destroy the very nests they were looking to observe. Plus, it was just plain dangerous to operate a helicopter as close to the mountain as was needed to do the job right.
Of course, along with fulfilling their contract, the two fliers were getting some spectacular aerial photography of the area they would compile with other films to create a documentary on the mountainous areas of California and the National Park system. The duo had been flying their aircraft in numerous pursuits from tracking the movement of wolf packs and bears to performing geomapping tasks in support of improving the cartography (mapping) of the remote areas. When the winds and thermals were cooperating, like they were today, the aircraft could stay aloft for a few hours. On less accommodating days they were restricted to the charge in the battery that powered the motor, a mere forty minutes.
“Hey! Look at this!” said Jake, turning his monitor so Lee could see it. “Check out the hawks!” The monitor clearly showed five hawks sharing the thermal that their drone was using. They had their wings unfurled, tip feathers in a graceful upwards arc as they followed the circling airplane.
“Excellent!” whooped Lee. “Start video on them. It’ll be great footage. Jake flipped a switch on his controller and used the controls to track the raptors. As they watched, the hawks all began to flap their majestic wings and climb above the aircraft. With the camera slung beneath the craft, the disappeared off the top of the screen. “Invert the image.” commanded Lee as he rolled the aircraft inverted. This allowed the camera to view what was happening above the aircraft. Upside down, the airplane didn’t develop the lift it could right side up, but it was worth some battery use to let the motor assist the aircraft to get close video of the hawks in flight.
“I think they’re warning us off. I wonder if they consider us competition or maybe a threat to their nesting or something.” commented Lee. “I’m going to roll back to normal flight.” Jake re-inverted the image as the plane rolled upright and Lee used his joysticks to swivel the camera, looking for the hawks.
A shadow appeared on the video monitor and suddenly the image shuddered. Both men looked at the aircraft with their bare eyes and watched as the hawks plunged at the airplane and used their talons to try to grasp its wings. Chunks of foam fluttered away from the aircraft with each hit. The airplane didn’t take well to the abuse, and with a sickening feeling, the men watched the left wing of the airplane fold back and separate from the craft. Out of control, the airplane spun and flipped down and down until it struck the upper branches of a large pine. It hung there for a moment and then fell from the limb and fell fluttering to the ground below.
The fliers looked at each other dumbstruck. They’d never seen anything like that before. They could see the wreckage of the plane at the base of the tree it’d hit. The camera was still working, it’s view canted and skyward. The limbs of the tree moved slowly in a breeze that wound around the mountain. According to the GPS readout, it was a half mile away. Not far, but a difficult trek over the sharp and craggy abutments of the mountainside. Sighing, they packed their equipment into the special rucksacks that carried the aircraft and supporting equipment. It took them an hour and a half to make the 2500 foot distance down to the airplane.
Both wings were damaged, one not anywhere in evidence they could see. The remaining foam wing suffered large gouges where the hawk’s talons shredded the foam. The fuselage was missing chunks as well, as though something had taken bites out of it. While the electronics and camera survived the incident, the airplane was history. They packed it up and scouted for and retrieved any pieces of foam they could find. While they hunted for it, they couldn’t find it and abandoned the search. The men then had to make their way five miles to the forestry road where their Subaru Forester waited their return. They were dehydrated and exhausted by the time they reached their vehicle. Legs aching, they climbed into the car and made their way down the rough track that barely qualified as a road.
The men stopped at a ranger outpost to report the incident. The ranger, a 15 year veteran of the Forestry Service listened as the tale was recounted. “I’m not surprised to hear this.” he said. “Hawks can be very territorial and stories like yours aren’t that uncommon. Even in some pretty urban urbanized areas have come reports of attacks against model aircraft. It seems to depend on their size though. Tiny models are ignored as are the larger aircraft. But those in the same general size of the aircraft tend to constitute most of the reports. No one knows for certain why they attack. We get reports all the time about raptors flying with sailplanes without incident. Most of the attacks seem to be on motorized aircraft. Maybe the motor or prop noise is interpreted as a challenge, or as you wondered, maybe they’re just protecting their space or nests. We really don’t know. By the way, thanks for making the effort to find and pack out the foam bits. Believe it or not, some animals will eat the foam bits and it can raise hell with their digestive tracts.”
“Well, there’s still a wing out there somewhere. I hope the sunlight breaks it down.” said Lee.
“Not much likelihood of that, but if it landed flat, any number of insects will make a home underneath it.” said Earl.
“In the future, if I see any hawks as we’re flying, I’ll cut the motor and glide back to the launch point. We lucked out that our camera didn’t get hurt in this. A Canon EOS is a pricey piece of equipment with the accessories, lenses and filters we fly. It costs most than the darn plane.” Lee replied.
This story was related to me by a couple of online buddies who share my interest in aerial cameras. Below are some YouTube videos of model aircraft attacks by hawks against R/C airplanes. -bk