Weather and Flight Experience
This past summer numerous forest fires in Quebec coupled with winds from the north brought a thick haze of smoke south into New England. I was in Maine for a few days vacation and before leaving my cabin for the Bar Harbor airport to retrieve the Warrior and fly home to Nashua, NH (KASH), I spoke with Bangor flight service who warned of haze and low visibility throughout the region; however, the outlook for improvement was good. Being a natural optimist, I expected to be home in a couple of hours.
When I arrived at the Bar Harbor FBO and listened to the ATIS, visibility was reported to be 6 miles in smoke. Based on the briefer's earlier prognosis of improvement, I decided to wait a while before taking off -- I'd still be home in a few hours. As suspected, as I sat at the FBO in Bar Harbor visibility went from 6 miles to 4 miles as the hours progressed. Each hour, I checked with briefers and each time they told me things were improving to the south (certainly couldn't tell from where I sat!).
My dilemma was this: leave now while the visibility is still 4 miles (marginal, but legal) and head toward the reported clearer air, or wait and hope for improvement at Bar Harbor. If I stay and wait for the impending clearing, it's a sure bet visibility would continue to drop. Despite reports of clearer air to the south from briefers, I wasn't comfortable taking off into the local low visibility conditions so I made the decision to rent a car, drive south and retrieve the airplane another day.
As I'm about to leave the FBO for the car rental counter, a pilot who just landed VFR told me things were not too bad at 2000 feet -- plenty of ground contact and forward visibility seemed to be several miles! So I called the briefers again -- this time they told me Portland was reporting 10 miles visibility and everywhere between Portland and I was better than 3 miles. I decided to give it a shot, fully prepared to return to Bar Harbor if things looked bad once I got off the ground. I mapped out a route direct from airport to airport moving down the coast, just in case.
At pattern altitude, everything looked good, but as I climbed, things got worse fast. I dropped back to 1500 feet where I felt pretty comfortable and stayed there -- good ground contact and as the previous pilot reported, I could see for several miles all around and no obstacles like mountains or big towers in the way.
Departing Bar Harbor to the southwest toward Portland one flies over numerous islands along the coast, but at one point between islands, I realized I could not differentiate between the water and the haze - they just blended together and suddenly all reference to land was lost. The visibility hadn't changed; just the distance between islands. At this point, I changed course direct toward the mainland and within a couple of minutes had land in sight again.
Haze, or smoke in this case, blends in with the water so there is no horizon; looking down doesn't help either without some other reference for what's level. I knew exactly where I was, so was confident that on my new heading, I'd see land ahead of me very quickly, even with limited visibility. If I were not paying close attention to my situation, I could easily have headed in a direction that would have taken me much longer to find a reference again -- and in the meantime, I had put myself in a dangerous situation. The smart thing to do in this situation is the same as for inadvertent flight into a cloud -- make a gradual 180 back to where you DO have a visual reference and keep your eyes on the instruments -- isn't anything to see outside anyway and I think you're more likely to lose control searching into the white nothingness than by concentrating on instruments in order to get back to a place that has something to look at.
I had flown in hazy conditions before with visibilities less than 10, but never over open water. 3 miles visibility over land isn't the same over water. Over land, you can see enough to keep a visual reference for which way is up; over water with the same visibility, you might as well be in a cloud -- you can see just about as much!