Flying Carpet: Pilots of wind and water

 ‘See where the river breaks over that wide rock?’ said our guide, Donny. ‘We need to be careful there because the water tumbles violently on the other side, like a horizontal tornado.’

‘What do you call that?’ I shouted as spray filled our faces. To cap off Parents Weekend at the Air Force Academy, Jean and I were rafting the Arkansas River with our son, Austin, through Colorado’s famed Royal Gorge. Our host was Raven Rafting of Cañon City.

‘We call it a ‘hole’ or a ‘hydraulic,’ said Donny as we emerged unscathed on the other side. Occupants of the other boat weren’t so lucky; a man flew overboard and had to be hauled in by his companions.

‘We pilots face related hazards in airplanes,’ I said. ‘Similar horizontal vortices form downwind of mountain ridges – we call them ‘rotors.”

‘Can you see them when you’re flying?’

‘Sometimes,’ I said. ‘If there’s enough moisture, ‘rotor clouds’ form in the eddies. Other times, lens-shaped ‘lenticular’ clouds form above the rotors; they at least offer some warning. But often there’s nothing visible at all, so to avoid them you’d better know the wind speed, and direction.’

‘I notice you mentioned eddies. Those form in river rapids, too, and where the riverbank takes a twist. Here, I’ll show you. Right side, forward two – now!’ Shouting orders to Jean, Austin, and I, Donny maneuvered our raft into a lull between the raging rapids. The boat idled calmly there with no help from us. Then he steered us sideways into one of those mean-looking horizontal rollers. There too the raft stood stationary, but only our combined weight leaning downstream prevented it from capsizing. Our guide watched gleefully as Austin submerged to his neck on the upstream side. ‘So you encounter similar challenges in airplanes?’ asked Donny upon releasing us into calmer waters.

‘We do indeed,’ I replied. ‘In fact we’ll face them on our flight home this afternoon.’ Intrigued, Donny asked about our route to Phoenix. ‘Assuming the winds aren’t too strong, we’ll negotiate mountain passes on either side of Alamosa,’ I said, comparing them to the narrow passage we’d just cleared between gigantic, jagged rocks. ‘Imagine rafting that passage upstream,’ I said. ‘That’s what it’s like tackling La Veta Pass through the Sangre de Cristo mountains in the face of strong winds.’

‘Sort of like rafting the river in springtime,’ said Donny, ‘when the water flow is much greater than now. Of course we don’t travel upstream like you do in airplanes.’ Warily, he eyed the rocky channel we’d just surfed. ‘Nosing upriver into those rocks with the river flowing over them… now that would be wild.’

‘It certainly can be.’ I said. ‘Wind plummets over mountains just like water over those rocks. In airplanes we use tricks like crossing ridges at a 45-degree angle to allow turning away at the last moment. Of course it’s wisest to assess conditions ahead of time before entering such uncompromising places. For example, if the winds are too strong at Alamosa we’ll fly down the Front Range to an easier pass near Santa Fe. You probably face similar decisions rafting.’

‘That’s for sure. You’d better know what lies ahead before passing the Highway 50 bridge, because beyond it there’s no escaping the gorge for eight miles. I call it ‘the bridge of no return.”

‘One difference in airplanes is that we often fly perpendicular to the ‘current.’ Flying through canyons with a crosswind compares to traversing that double row of rocks up there crosswise.’ I explained how pilots use such conditions to their benefit, like flying on the downwind side of canyons to take advantage of updrafts. As if to prove that anything achievable in airplanes is also applicable to river rafting, Donny steered us suddenly across the current through that double row of rocks. ”Passage ferrying’ we call it,’ he cried, ‘Right side forward three! Lean left!’

Soon we craned our necks upward at the Royal Gorge Bridge, highest suspension bridge in the world. Next to it undulated a pendular speck. ‘See those people swinging over the gorge on the Skycoaster?’ said Austin. ‘If only the waiting line had been shorter yesterday, we could have done that ourselves.’

‘You and Mom maybe,’ I said. Swinging on a sling over a 1000-foot canyon held little attraction for me. ‘Funny that you can love airplanes and not like heights,’ observed Donny. ‘It’s all about who’s in control,’ I said. ‘You probably feel the same way about rafting the Royal Gorge.’ Donny nodded approvingly.

Departing the canyon downstream, the four of us went on comparing notes about our respective roles as pilots – Donny on the river and we in the skies. Just as Donny knew every rock, rapid, and tourist pleaser along his stretch of the Arkansas River, we aviators had memorized our frequent aerial route from Colorado Springs to Phoenix: those daunting mountain passes, Great Sand Dunes National Park, narrow-gauge railroad tracks marking the Continental Divide, and the Native ruins of Chaco Canyon with their crown of ancient roads diverging like rays of the sun.

Yet even being so familiar with our respective journeys, we agreed that unpredictable factors of wind, current and weather make every passage a new and formidable adventure for each of us. In fact, for every challenge faced by one sort of pilot, the other found a parallel – it soon became a friendly competition between river and sky.

By now the four of us coasted serenely on the final stage of our trip, pausing occasionally to swim along the way. ‘You don’t get to do this in airplanes,’ said Donny as he bounded grinning into the water from our raft. ‘That’s for sure,’ agreed Jean and I in unison as we floated side-by-side on our backs.

‘Well, I do,’ said Austin, preparing to jump into the river from a giant rock. ‘I’m taking parachuting next semester.’

Photo 1. Donny guides our raft through Arkansas River rapids in Colorado’s Royal Gorge. Photo by Rapid Image.

Photo 2. Just as water pouring between rocks threatens rafts riding river rapids, airplanes are buffeted by wind spilling through narrow passes. Here Medano Pass slices Colorado’s 14,000-foot Sangre de Cristo Mountains. (Great Sand Dunes National Park and the snow-covered San Juan Mountains are visible on the other side.)

Map 1. Just as our river guide Donny knew every rock and rapid through the Royal Gorge, we aviators had memorized the peaks and passes marking our aerial route from Colorado Springs to Phoenix.