Wind Gone, Thunderstorms Arrive

My lessons on learning to fly in weather continue on a new track.

It’s monsoon season here in Arizona.

Monsoon season is the time of year when there’s a seasonal wind shift that brings moisture off the Gulf of Mexico up and into New Mexico and Arizona. (It may get as far north as Colorado and Utah, but I think we get most of it.) Most days start off sunny and pretty clear, with just a few friendly clouds floating low in the sky. But then the sun kicks in and puts those clouds to work. Convective activity builds them into towering cumulus clouds that move in an east to west flow (sometimes southeast to northwest; sometimes northeast to southwest). The clouds build very quickly and, after a while, gang up to form storm cells. The rain from the biggest of these clouds can start as early as lunchtime. But if they’re still around and still building in the afternoon, they turn into ugly cumulonimbus and start throwing lightning bolts and, on occasion, hail.

Fortunately, these storms are extremely localized and easy to see. Pilots flying at our altitudes (i.e., 300-500 feet above the ground) can usually fly around them. We can even get pretty close to them if we have to.

On Wednesday, my first day back to work, I got my first t-storm lesson. I was a spare pilot, flying someone else’s ship for lunch. I was returning from a tour, about 3 miles out, when a lightning bolt came out of an innocent looking cloud and struck the ground about a half mile away from me. I immediately saw smoke in the trees near where it had struck. Shit. I hurried back. When I made my 2-out call and they told me my next flight, I told them about the lightning, sure that they’d put on a weather hold. Silly me. I was told I’d better get used to it.

Later, the Chief Pilot told me that I was actually safer in the air than spinning on the pad when there was lightning around. Lightning wanted to hit the ground, not something in the air. I found his words comforting. (If they’re not correct, please don’t tell me. I’d prefer blissful ignorance on this topic.)Yesterday, I got a better lesson. I was the top priority pilot, which meant that I was going to be flying all day. That was fine with me. I’d rather fly a helicopter than waste time in the break room. The storms built up magnificently throughout the morning and by lunchtime were raining down in various places on the North Rim and far to the east. I had a lunch break and returned to fly at 1:20 PM. The storms had built up and were darker than before. I did a few flights and had no trouble staying clear — the storms weren’t on our route.

But then I did an Imperial Tour, which took me to the east. A storm I’d spied out that way seemed very close to Grandview Ridge. The tower had even commented on it. When I got out to Grandview, it was raining heavily on us, but we were on the storm’s northern edge. The lightning was still about 2 miles to our south. The temperature had dropped considerably — enough for me to close both vents — but the air was still smooth, with no heavy winds, updrafts, or downdrafts. I made a pirep to our company frequency, telling them about the storm and that it was still good to fly on the east side. Then we broke out of the cloudy area and were treated to views of a sun-drenched painted desert and the spectacle of the Little Colorado River’s flood flow turning the Colorado River brown at the confluence.

I was at the Split when I heard some chatter on our FM frequency. It appears that the storm we’d skirted had come straight to the airport. It was dumping “quarter-inch hail” on the helipad. Chuck’s voice sounded unusually perturbed as he reported all this to everyone. Visibility was zero-zero. He told the pilots on their way back to stay clear. To land near the ponds. No, the storm was moving that way fast. Land near the triangle.

What followed was chatter between the pilots in that area, deciding what they were going to do. By that time, I was over the North Rim and had a clear view to the south. Although I could see the South Rim, anything beyond it was lost in a dark gray cloud. With lightning. I got on the FM frequency and told them where I was. Should I double back and return the way I’d come so I could come in behind the storm? I was advised to continue. Although I doubted the wisdom of that, I followed orders. These guys had far more experience with canyon storm systems than I did.

The chatter started up again. AirStar, another helicopter company, had flown south to Red Butte and was able to come in from there. The pilots about to land (or landed, perhaps) decided to circumvent the storm system by flying around its western edge to the south. One by one, they made their way home and were told to shut down. Soon, I was one of only two pilots still in the canyon, now in the Dragon Corridor. The other pilot, Tyler, was about 15 minutes behind me, doing the same tour I was.

At first, it didn’t look good. There was definitely a storm system in front of me. But by the time I got to Dragon’s Head, I realized that it was two separate storms. Dripping Springs, where I had to fly, was remarkably clear, with a storm on either side. I reported this to Tyler when he asked. He sounded nervous. (But that could be his voice; he often sounds like that.) When I got to Dripping Springs, I got a good look at the storm that had hit the airport. It was a monster, right on my usual flight path, a wall of gray that completely blocked out everything. No flying through that. But I could clearly see Red Butte in the distance. I reported all this to Tyler. Someone got on the FM radio and started giving me detailed instructions how how to get it. But I didn’t need them. It was pretty obvious where I had to go. I made my call to the Tower. I told the controller where I was and what I planned — to skirt the western edge of the storm and come in from there. The controller read me the ATIS info, I thanked him, and continued in.

HailA moment later, I could see the tower. The airport looked clear. I reported this to Tyler, too. By this time, he was at Tower of Ra, still about 3 minutes from the Rim. It would be close for him, especially if the two storms decided to merge. I called our tower about three miles out and was assigned a pad. Then I called Grand Canyon tower and was given permission to cross the runway. It was raining lightly there but my landing was uneventful. All the other helicopters were already there, tied down. There was hail on the ground, making the scene look more like something out of a Christmas card than mid-summer. Here’s a photo I took later of the hail on the ground. I included my shoe to give you an idea of size. The smallest of the ice pellets was about the size of a pea. Some were about twice that size. Amazingly, there were still piles of the stuff at the bottom of gutter drainpipes at the Papillon hangar midday, the next day.

Tyler came in just as I was tying down my blades.

What do you think?