Engines

Some inventions seem to be naturally bad ideas but work anyway, while others are bad ideas that don’t actually work that well. In-tank electric fuel pumps are an example of the first, the Bendix dual mag as a poster child for the second. But not for much longer.Earlier this year, in a terse two-line press release, Teledyne C ontinental announced that its discontinuing manufacture of the D2000 and D3000 Bendix magnetos. No details were offered nor provided by follow-up query, but we can connect the dots. D-mags arent used on any Continental engines, just Lycomings. Litigationally speaking, theyve lived a rough life so Continental must have figured why have the legal exposure just to supply a competitor with a few mags. Even a Goldman Sachs executive could figure that one out.

With more and more Rotax engines out in the field, it makes sense that there is a growing market of aftermarket parts and accessories. However, this is purely good news for owners of Rotax engines on experimental aircraft, including E-LSAs. For owners of S-LSAs-factory complete LSAs not registered as experimental-the usefulness of these parts depends on what it is and which aircraft they own. S-LSAs don’t use the STC process many aircraft owners know and love (or not). Instead, almost any modification can be made with a letter of authorization (LOA) from the aircraft manufacturer. These LOAs are supposed to be issued on an aircraft-by-aircraft basis. So, just because your hangar neighbor with the same LSA has an LOA for a particular change, that doesnt give you the right to do it. That said, the more organized LSA manufacturers keep common LOAs ready to go for customers who request them.

As we attempt to keep our legacy aircraft flying longer and more efficiently, more pilots look to the avionics upgrade path as a means of improving utility and safety. And while the glass-panel primary flight display and multifunction display have both earned their fair share of attention, its also correct to suggest that the combined engine monitor-shorthand for a screen that includes powerplant and airframe system monitoring-is on many owners radar. Who isn’t eager to get rid of those wiggly needles, anyway? J.P. Instruments has been a household name in add-on engine monitors, making popular the bar-graph style of EGT and CHT monitoring. Many pilots are familiar with the firms 2.25-inch gauges and while some of them can include monitoring of other engine parameters besides EGT and CHT, the limited display size reduces the number of items you can watch at once.

Think of it: If you had an aircraft engine that burned two to three gallons less than the competition, delivered the same horsepower, weighed more or less the same and burned fuel that isn’t threatened with extinction, as 100LL is, wouldnt you sell the hell out of it? Youd think so. But while SMA, the French daughter of aerospace giant SAFRAN, has such an engine in the SR305 aerodiesel, buying one is at best a rarified experience. There arent many of these engines flying, so judging their merits has been largely a paper exercise. So when the Paramus Flying Club, a long established New Jersey co-operative, invited us to examine their SMA-converted Cessna 182, we realized it represented a rare opportunity to take the measure of this engine in the wild. The club has been operating it for nearly a year and while its too soon to declare it a walk-away success, the airplane has proven to be the most popular among the clubs 46 members, its dispatch reliability has been excellent and the engines initial operating costs look promising.

Owners buying engine overhauls have more or less adjusted to the idea that cylinders, cams and crankshafts have become a crap shoot. But valve lifters, too? These got added to the list of problem parts last fall when TCM announced that a massive batch of faulty lifters made it into the supply chain. Some showed failure wear in as little as five hours of operation. Although only engines built after June 19th, 2009, appear affected, the sudden demand has disrupted the supply chain for lifters to the extent that the industry-and the FAA-are relenting on the standard recommendation that lifters be replaced. Further, the market for overhauled lifters has become red hot and, at least we’ll into 2010, they may be hard to come by. Only owners who had engines built after the June date need be concerned about bad lifters and not all of them may be affected.

Despite being one of the bigger players in LSA market, Tecnam Aircraft isn’t we’ll known in the U.S. The company has actually been building aircraft and aircraft parts for over 60 years, and has 3000 aircraft flying worldwide. For comparison, Cirrus Aircraft and Diamond Aircraft have each delivered slightly over 4000 airplanes to date. Tecnam is reorganizing in the U.S. with a new website (www.tecnam.net), an expanding dealer and support network and a new aircraft: the Tecnam P2006T light twin. The P2006T (That name doesnt quite roll off the tongue, does it?) has specs more like a single than a twin. Its gross weight is only 2601-50 pounds more than a Cessna 172SP-and cruise speed is in the 140- to 150-knot range. The really novel item is that the P2006T sports two Rotax 912 S3 engines. The S3 is the certified version of the Rotax found in most LSAs. Each engine puts out about 100 HP.

One perennial rite of passage for aircraft owners is what to do about cylinders at overhaul. Whether were talking about top-end work on a mid-time engine, or one we’ll past its published TBO, which cylinders to install can be a major decision. And its not getting any easier. In fact, there’s an element of crisis in the cylinder business. Superior Air Parts was once a major supplier, but is gone from the scene. Continental and ECI have both suffered significant quality issues affecting thousands of cylinders. A recent AD impacts owners of existing Superior cylinders, rendering what was once the cream of the cylinder crop as one-run wonders. One way out of that morass, of course, is to buy a new or factory-rebuilt engine: you’ll get factory jugs. But given Continentals troubles, thats no panacea, either. For those facing top-end work or an overhaul, the choices are more complex. And theyve gotten even harder in recent years given the aforementioned ADs and bulletins. Lycoming owners have it a bit easier: There are no recent ADs against factory cylinders or those supplied by Superior. But anyone with an aftermarket cylinder or flying a Continental engine is probably feeling a little paranoid about all this. After the last three years of ADs, whats going on? Cant anyone make a cylinder anymore? What do engine rebuilders recommend? And what should an owner do when its time to replace one or all of an engines jugs?

Despite the company having been around for some 90 years, powering an aircraft with a Rotax engine is something relatively new to most general aviation pilots in North America. Until the onslaught of light sport aircraft began five years ago, many had never even heard of a Rotax engine, despite their popularity and penetration in the power sport markets (motorcycles, snowmobiles, ATVs, personal watercraft and so on). As a result, these days its likely an ultralight, experimental or LSA you own or plan to fly is powered by a Rotax engine, part of Canada-based Bombardier Recreational Products Inc. That high level of market penetration means more and more Rotax engines are in service. Because of their increasing popularity, we wanted to find out about owners experiences with them, including maintenance frequency, factory support and overall costs of ownership. To find those answers, we crafted a 13-question ownership survey and made it available through our online sister publication, www.avweb.com, in early September. The results show owners are generally happy with their engines, and most maintenance issues are easily handled. But finding someone to work on them at an out-of-the-way location might be a challenge. Thankfully, the Rotax dealer network appears to be meeting owners needs, and those flying in the experimental category generally find the engines to be easy enough to work on themselves.

Pity the poor turbocharger: It sits in your engines exhaust stream, subject to extreme heat and corrosive gases, spinning at up to 120,000 RPM, boosting manifold pressure. Pity also the turbocharged aircraft operator, since he or she gets to pay for maintaining and overhauling the turbo, its controller and its wastegate. Although turbos often last as long as the engine itself before needing overhaul, they also can need attention we’ll before scheduled TBO. And, even if the engine doesnt need work before an overhaul, you might want to consider overhauling the turbo halfway to the engines TBO anyway. Its sort of like paying it forward. In some cases, problems with the engine can mean turbo issues, too, since they share the same lubricating oil; what gets into your engines oil also can get into your turbo. Whether your turbo is sent out for overhaul with the engine or removed before TBO after a routine inspection uncovered a problem, there are few things you need to know and decide before giving the shop a go-ahead for work.

Does the world need another turbocharged Cirrus SR22? Continental thinks so, because at AirVenture Oshkosh it rolled out its long-rumored TSIO-550 demo project for the SR22. We know this project has been an on-again, off-again effort between Cirrus and Continental and now it looks like its on again, at least from TCMs point of view. Currently, Cirruss turbocharged offering-its best seller-is the turbonormalized set-up engineered and provided by Tornado Alley Turbo. The aircraft retains the stock 310-HP IO-550-N but with the addition of two turbochargers and lots of intercooling. Unlike traditional systems from Continental, the Tornado Alley system doesnt ground boost the engine but allows it to maintain sea-level manifold pressure we’ll into the 20s. Technically, the turbonormalized system doesnt have a critical altitude since it boosts to sea-level to the airplanes certificated ceiling of 25,000 feet.

Think of Florida on a warm afternoon in July and youve got a good grasp of what your engine crankcase is like after you shut down after a flight. Throw in a little acid rain to season the heat and humidity to complete the picture. In short, the inside of an engine can be the perfect Petri dish for corrosion. Engine dehydrators or preservers are designed to address this by either pumping dry air into the engine, or sucking the humid miasma out of the crankcase and replacing it with moisture-free air. The idea has enough credence for three companies to have introduced dehydrator products. The latest comes from Tempest/Aero group, which adds a dehydrator to its well-regarded line of dry vacuum pumps and oil filters. The AA1000 Engine Preservation Systems retails for $235.Like the other engine preservers, the Tempest dehydrator pumps dry air into the engine after first passing it through a silica gel desiccant. The device consists of a small plastic enclosure about the size of small fishing tackle box-it may actually be a tackle box, by the looks of it-divided into two compartments. One compartment serves as a cell to contain the desiccant, which consists of about a pound of tiny blue beads. You just pour them in the box, making sure that the filtered pickup tube is near the bottom of the desiccant. The other two thirds of the box houses a small, continuous duty low-volume air pump powered by line voltage. A clear plastic tube exits the pump to be inserted into the crankcase oil filler.

If economic recovery requires the restoration of confidence, we have a suggestion: Just bottle up the bounding confidence that the developers of aerodiesels have that Jet-A engines are the future and distribute it to the general population. Although the aerodiesel market has, at best, stumbled along looking for serious traction, the unswaying conviction of those in the diesel industry seems to be that Jet-A piston engines are an inevitability. According to our count, there are six active projects in the aerodiesel arena: Austro, Centurion (formerly Thielert), DeltaHawk, SMA, Gemini and Zoche. (Remember them?) Heres an update on each.What we found most interesting about the current state of the aerodiesel market is that its four to two in favor of purpose-built aircraft engines rather than engines adapted from the auto segment. The automotive crossovers are Austro and Centurion, both of which are adapted from widely successful Mercedes Benz automotive diesels. SMA, DeltaHawk, Gemini and Zoche are all clean-sheet designs developed specifically for aircraft. Thus far, the only remotely successful aerodiesel is the Thielert (now Centurion) 1.7 and 2.0 liter diesel series which Diamond enabled by adopting it for the DA42 Twin Star and the DA40 TDI.