Twins: Twice As Much Fun?
By Peter Conant - Although I have a twin-engine rating I don't have a lot of twin time, maybe 80 hours. My twin rating was done in a Piper Seneca I, which wasn't all that much faster than an Arrow but was a good learning tool. I took a trip to Kalamazoo, Michigan in the Seneca soon after receiving my rating in October, 1993. Crossing Lake Erie after dark in a snowstorm is something I would never do in a single, but the presence of that second engine gave me and my wife a sense of security. Later I found out just what a false sense of security that could be. Still, I enjoyed the snow being lit by the strobes over Lake Erie as a sort of stop-action film. It was a clear night in Kalamazoo and I appreciated the tower clearing me for the visual, but I asked for and got the ILS. Note to self: always fly an approach, if there is one, after dark when landing at an unfamiliar airport, especially one with lots of lights and three runways.
A few years later I checked out in an older Cessna 310. Whereas the Seneca had, as I remember, 160 HP engines, the 310 had 265 HP on each side. It had a phenomenal climb rate, huge amounts of space inside, great load hauling capability and great flying qualities. My checkout was in February with the whole drill again that I'd seen in the Seneca: stalls, single engine minimum controllable airspeed, Vyse climbs (single engine best rate), single engine landings, instrument approaches under the hood with an engine failure inside the marker, go around procedures and more. My instructor told me to remember "puff" for a go around: Power, Undercarriage, Flaps, Flaps (for cowl flaps). The 310 didn't have cowl flaps though.
In late July of that same year, my wife and I decided to fly up to Grand Manan Island in New Brunswick, Canada. Grand Manan is sometimes referred to as the cork in the Bay of Fundy. Grand Manan airport only had an NDB approach but we saw clear skies forecast for the trip of just under two and a half hours from Bedford, Massachusetts.
It was a hot day when we departed after 1 PM from Bedford. After climbing to 5,000 MSL I leveled out, brought back the engines to 65% power in cruise, and started leaning the mixtures just as I had been taught.
Without warning, the right engine began to surge. We were swinging left and then back to center as the right engine died, coughed, caught, coughed, died and generally acted cranky. The first thing I did was to shove the mixtures to rich. The second thing was to calm my wife, who was asking "Is this normal?" Oh sure, I said, we practice this all the time in training, all the while thinking "What the hell is going on with these engines?" I kept the mixtures full rich for about 20 minutes before cautiously leaning them. Whatever the problem was had apparently gone away. Blocked fuel lines? Air bubbles in the fuel? Faulty maintenance? I just could not think what the problem had been.
The Bay of Fundy was shrouded in clouds when the arrived and I prepared for the NDB approach. But just then, the island showed through a break in the clouds. The entire island no less, radiating enough heat through the fog to create its own column of rising air. Or maybe we just got lucky. I made a great landing (he said modestly) and even impressed myself. Grand Manan airport is an Airport of Entry, allowing us to clear customs in record time. Our rental car was waiting for us and the driver, also the rental agent, took us to his house where we signed the necessary documents at his kitchen table. It turned out the car was his own personal car and we were being given the use of it for the weekend. A very pleasant, laid back and congenial way to start our visit to Atlantic Canada.
Grand Manan was once the center of a thriving sardine industry. It also produces dulse, a dried seaweed which the Canadians eat like potato chips, but to us was way too salty. The sardine docks and packing houses are largely abandoned but a few have been bought up by a New York architect and remodeled into his waterfront vacation home. He even has one building identified with a sign as the "Sardine Hall of Fame" with displays of Grand Manan's historic past. To top that off, he's got a boat in the harbor in the shape of a sardine can with the top partly rolled back.
We enjoyed our hikes to the cliffs, dipping our toes in the cold ocean waters, touring the lighthouse and enjoying the geology of this unspoiled island. Had we more time we would have gone on a whale watch or taken an afternoon trip to Seal Island to watch the pinnipeds and puffins in their native environment. The weather was cool in the afternoons and cold in the evenings. In the morning as we were getting set to leave, we stopped by a fish market which sold us cod which had just been brought in on the fishing boats. Then to a local baker who sold us several loaves of freshly baked bread, and wished us goodbye by saying ìGood Appetite!î Atlantic Canada still has its remnants of French culture, which although more concentrated in Quebec still remains alive along the New Brunswick seacoast. I realized as we drove away that what he had said was "Bon Appetit" in English!
The weather at the airport was close to zero-zero. I walked the length of the runway to check the visibility and by the time I reached the middle I could not see either end. Even with a twin, I was not prepared to take off in those conditions. We still had the rental car, which the owned said he would pick up later at the airport, so we headed back into town to do some serious beachcombing and get warm with hot coffee.
After a few hours we returned to the airport, only to find the airport manager politely telling us that the Canadian Air Traffic Control people were looking for us. Oops! I hadn't realized that in Canada you need to cancel your IFR flight plan rather than just let it run out. Unless they hear from you by radio or phone, they assume you have departed and have lost communications. Whoops! Big mistake. I re-filed the IFR, apologizing to the very tolerant and understanding flight service people.
We waited until the ceiling got to what I estimated as 200 to 300 feet with a half-mile visibility. I decided to launch. Everything went fine and we popped out on top at 2,500 and took up our course to Bangor, Maine. I leaned the engines with no ill effects. By now it was mid-afternoon and after landing we decided to stay in Bangor for the night. The next day dawned bright and clear and warm. I fired up the 310, launched the big bird and turned toward Bedford. Leveling off at 6,000 I leaned the engines.
And guess what? A surging right engine greeted me! As we rocked and rolled from side to side I set the mixtures back to full rich which cleared up whatever the engine problem was. Again, after about 20 minutes I was able to lean without any difficulty.
I reported the incident to the owner and to the flight school I had rented from. Several months later, my instructor called me to say he had been looking over the POH and found this statement: "When flying at altitudes over 12,000 feet MSL, or when operating in extremely high temperatures, do not attempt to lean the mixtures until at least 15 minutes after takeoff. Allow the fuel flow to stabilize, after which leaning procedures can be attempted." The 310 had no cowl flaps, and the heat-soaked engines were vaporizing the fuel in the lines. Even though these were fuel-injected engines, the heat of the day plus the heat of the engine acted to block the fuel lines, which were located at the top of the engine block.
Flying in new conditions, atmospheric or otherwise, should always bring with it skepticism about whether the airplane will perform the same way it did when you were checked out. And now I ALWAYS read every word of the POH for whatever airplane I'm flying.