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DECEMBER 2015 TWIN & TURBINE • 19New considerations go into flight planning these days – all because of those darned LPV minimums and fuel price displays.Two Different AnimalsI’ve read articles discussing the question of increased risk associated with GPS/LPV approaches. Although we may not be up to low-IMC approaches as a regular diet, are we flying into or over lower IMC than before, simply because our electronic magic makes us more comfortable? There are several sides to this dilemma. Number one, we can plan and fly trips in which the weather will be 400/1, knowing that the approaches we need are available most everywhere. Two, we can fly the trip with weather that is better (say 600/2), knowing that, if the forecast was wrong or the weather deteriorates, we can still find those magical LPV minimums nearby. And three, we can more comfortably fly over an extended area of low IMC, feeling secure that, if we need to land immediately, many airports with LPV minimums are under our wings. All valid points, but I can tell you from experience, perhaps the point of this article, that having LPV minimums available along your route of flight, and actually flying a single-engine, single-pilot approach to those minimums, are two different animals. Add night time or icing to the picture and things could get very uncomfortable. And I’m not talking about a wet head or pants. We must decide before we launch: are we the pilot to fly that approach on one motor to LPV mins? Which brings us back to my comment in the opening paragraph and the newly installed Garmin 430W providing a critical capability.There I was, on a dark and scary night, a dot low and inverted on the glideslope, two inches of ice on the wings, both motors coughing. Sorry, that’s an old joke about trying to make our stories sound bad to highlight that they got our attention. Most engines will cough if you flyinverted and what’s one dot among friends anyway? This event did get my attention though; all of it. Due to the “fetch” phenomenon, the weather within an hour in any direction was 400/2. It was daytime, the ice was trace-rime at cruise and “only” one motor had an issue. I consider my instrument crosscheck to be very thorough because that’s what others tell me. My flight instrument and navigation crosscheck is professional, but my engine crosscheck is constant and concentrated. I can’t afford to hurt the engines in the Duke and, after three engine failures at work, I watch the parameters closely. It paid off. As you know, analog gauges make it easy to notice when the left and right needles are not parallel. The right engine oil pressure gauge was about one-quarter scale lower than the left. Unstrapping from my seat, I slid over to the right seat and looked at the motor – no visible clues. After moving back to the hot-seat, I looked at the gauge again: even lower and slowly decreasing. Damn, this isn’t happening.How Slow? Don’t AskPulling the throttle back didn’t help, as the pressure continued to drop. The last thing I wanted was for it to seize and throw a prop blade or break an engine mount. So I did it: prop to feather, mixture to cutoff. I declared the emergency, ran the rest of the checklist and selected an airport: Lancaster, Ohio, an uncontrolled airport, paved runway with HIRL, VASI, and a GPS approach with LPV minimums of 200 and 1⁄2 mile. This would be only the fifth or sixth approach to LPV mins with the new 430W and the first in weather all the way down. And my first real- life, IMC, single-engine approach in a GA airplane. Like most piston twins, a go-around from low altitude is a 50/50 proposition and likely not possible after gear extension–this would have to be done right the first time. I porked the final approach course intercept because I forgot to execute the approach mode. Bythe time I noticed, it was too late to salvage the approach. During the 360 to re-intercept final, I got slow. How slow? Don’t ask, but I can tell you with one throttle at idle, the gear warning and stall warning use the same horn. The landing was fine, but to say the approach was sloppy would be generous. It turned out to be a loose oil line. Four quarts (out of ten) remained after landing. Mechanics Darrell and Jim found the leak in minutes, fixed it, added oil, cleaned it up and that was that; less than $200. After a night in the local hotel to contemplate life, death and clean out my shorts, the next day found the Duke back in the soup, headed home.The Feds (who happened to be there the next day doing a bird- strike investigation), pilot friends and family all said, “well, you landed out of it, with crappy weather on one motor, and didn’t bend any metal – good enough.” I suppose so. But I pray to never fly so poorly again. I’m grateful to have had WAAS GPS to help guide my sleigh. It’s even better than a glowing red-nosed reindeer. Now that winter is upon us, with the associated low visibilities and runway contamination, remember to evaluate and manage the risks – including an honest look at your fitness and proficiency. I know I will. T&T•Kevin Dingman has been flying for over 40 years. He’s an ATP typed in the B737 and DC9 with 21,000 hours. A retired Air Force Major, he flew the F-16 then performed as a USAF Civil Air Patrol Liaison Officer. He flies volunteer missions for the Christian organization Wings of Mercy, is employed by a major airline, and owns and operates a Beechcraft Duke. Contact Kevin at Dinger10d@ gmail.com