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When will a diesel be available for my aircraft? |
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News, facts, and comments on the coming revolution for piston-engine aircraft.News of September 30, 2007When will the aerodiesel revolution reach the United States?My perception from the fascinating feedback I get through questions from subscribers, and from my own experience when I happen to fly in France and interview European private pilots, is clear: Outside the United States, including even Canada and Mexico, everyone is aware that the aero diesel engine is not the best way but the only way for small piston-engined aircraft to find a new future. Whether it is because of poor availability of Avgas, or of a humongous price difference between Avgas and JetA ($16 per gallon against 6 in some parts of Africa!), or because of the unique advantages of diesel in terms of much longer range, higher altitude therefore more speed for same power, security in case or low fuel, much simpler learning process for the student pilot (one single control instead of 3 even in constant speed propeller, accurate power control on final approaches, highly increased payload on shorter distances), the world is convinced. What about the US? It is coming, but still very slowly. The US has by far the largest fleet of piston-engined planes (some two thirds of the world) including a large fleet of old, airworthy 172s and 182s which can be converted right now. But the owners of these planes all do the same reasoning: If my plane is worth, say, $80,000, and it costs $65 to 85,000 to convert it, why don't I simply trade my plane for a better, more expensive plane instead of taking the risk of losing market value? And how can I amortize such an investment with my small flying time of say 50 to 100 hours per annum and with hardly any difference between JetA and Avgas prices? Yet,it is coming surely because, as sales develop, the market value of diesel planes will soon consolidate and show a gain; and because, as exposure increases, US pilots will see for themselves that a diesel plane is not any ordinary plane spending less on fuel, but a very superior plane, as Europeans already know. If you are a private pilot in the US, and are considering right now buying any piston-engined airplane worth between $200,000 and 800,000, whether used or new, contact us. We will tell you what the diesel market offers right at the time we receive your inquiry. posted at 11:32 AM Read Plane and Pilot of this month to learn all about the Maule SMA turbo-diesel.Maule Air has presently 7 diesel planes in the shop. Brent Maule says that the backlog is growing, and they are confident that the plane will be certified for Sun n Fun. Bill Cox flew the plane, and writes: 'I dont know about you, but I cannot imagine a world without avgas. Within a few years, I may need to stretch my imagination. The reality is that avgas may not be with us for more than about another decade (if that long)… Maule Aircraft of Moultrie, Ga., has adopted a diesel, in this case, a French SMA, to power one of its line of bush planes. Societe de Motorisations Aeronautiques (SMA) of France is one of the oldest companies in the business of adapting diesels to aircraft, and it is now a wholly owned subsidiary of the French jet-engine conglomerate Snecma. SMA began developing an aviation diesel in 1998 and earned FAA certification for its first product in May 2004... From the firewall aft, there are few differences between the standard avgas Maule M-7 and the new Diesel M-9. Adapting the diesel does demand different instrumentation and controls and larger fuel filler openings atop the wings to accommodate the larger jet fuel nozzles. The panel includes change-outs of several gauges: manifold pressure, tachometer, oil pressure and temp, cylinder head temps, turbine inlet temp and fuel level (graduated in pounds rather than gallons). .. The sensations of takeoff are not that different from what you would experience in a standard Maule, provided you ignore the manifold pressure gauge. Takeoff power is about 90 inches of manifold pressure (yes, we said 90 inches, and no, dont expect to see any Maules running the pylons at Reno), purely a function of the diesel s turbocharger. Climb is similar to that of a standard Maule at sea level, but the diesel airplane gradually pulls away from the avgas model as the ground falls away, owing to the airplane s turbocharger. Above 5,000 feet, the diesel version will easily leave the avgas Maule behind… Using the Maule M-7 standard O-540 or IO-540 as the logical examples, avgas SFC works out to about 0.48 pounds/hp/hour at full power, 0.44 pounds at 65%. Converted to diesel power, the same airplane scores more like 0.35 pounds/hp/hour at all power settings. In more familiar terms, that means the SMA-powered Maule will cruise along at 75% power on about 8.5 gph, whereas the stock airplane will burn 11 to 12 gph… Cruise numbers between the two engine types are similar at lower altitudes, but the SMA-powered airplane s turbodiesel really begins to shine at higher altitudes where the turbo begins to provide some advantages. Critical altitude (the maximum height at which the turbo can supply sea level air) is 10,000 feet. Up at 12,500 feet, the diesel manages 138 knots compared to more like 130 knots in a standard Maule. The 12,500-foot altitude is currently the limit on the SMA Diesel Maule, but the company is hoping to receive approval for a step up to a max altitude of 20,000 feet in the near future… Maule hopes to certify the M-9-230 diesel at 2,800 pounds gross on wheels, and the airplane on display at this year Oshkosh AirVenture had a redesigned wing root section and tougher main landing gear to accommodate the higher weight. When the M-9-230 is certified some time next year, Maule hopes to offer a greater than 1,000-pound useful load for a 430-pound payload after full fuel. Like most previous Maules, the M-9-230 is a master of utility, with four doors to feed five seats or a quick-change option that allows pulling the aft seats to open up a large cargo area. The target price for the new Maule M-9-230 diesel is $250,000, and it is a safe bet there will be a number of takers. Many bush operators who fly a variety of aircraft ranging from Helios and Twin Otters to Maules will probably be delighted to stock their outlying strips with a single type of fuel. Similarly, there are also a number of places in the world where avgas may be simply unavailable. It is already happening in certain parts of the South Pacific.” posted at 5:36 AM News of September 14, 2007A new aero diesel: The Raptor Turbo Diesel for the LSA marketRaptor Turbo Diesel proudly announces the Birds of Prey line of aviation engines. First of this series of engines is the Raptor 105. Currently in development, the Raptor 105 is a 105 horsepower, FADEC controlled, common rail turbocharged diesel engine designed expressly for the Light Sport Aircraft (LSA) market. It is a 4 cylinder in-line, 4 stroke cycle, liquid cooled, Propellor speed reduced engine with Common Rail injection. Power: 105HP. Weight (without details): 179 Lbs. The website http://www.raptorturbodiesel.com shows photographs of the engine, says it has not flown yet, and says nothing of the manufacturer: Vulcan aircraft Engines. posted at 11:06 AM Good news on customer service and performance issues on aero diesel airplanesSince we published our special report on the Diamond-Thielert controversy, we must report some good news: we had several spontaneous reports from European owners of Thielert-equipped Diamond DA40 and Cessna 172, stating that they had had no significant problems with service and spare parts, were very happy with their purchase, and would remain loyal to diesel and to their airplane. This would confirm therefore that there is no basic vice either in the engine, or in the plane, or in the concept of aero diesel. As for the Cessna 182SMA, a very impressive report was published in Aviation et Pilote, a leading French General Aviation periodical. The author, Emmanuel Davidson, purchased a 182Q and converted it with the SMA diesel kit and has flown 300 hours with it. He gives (in French) a 6 page report on the maintenance costs and the performance. He is highly satisfied. Compared with his previous plane, a Wassmer 180HP, he reports that his 200h fuel cost has gone down from Euros 13,760 to 6,006! (Reminder: Jet fuel is much less expensive than Avgas in Europe). His only engine alert was his own fault: A start up conducted too hastily, provoking a red signal from the Electronic Control Unit. He mentions a range at 12,500 ft. of max. 1,470NM at best economy speed if you are patient enough to wait for 13 hours, and of 1,100 NM at 135 Knots (8 hours); this last figure against 817NM at 8,000 ft for a basic 182 at same speed. Superbly ignoring the FAA STC which limits altitude to 12,500 ft (we are in Europe), he reports a climb speed of still 275 ft/mn and a true calibrated speed of 157 Knots at 22,500 ft. He also says that because he got rid of the old and heavy ADF and DME, he finds himself with the same empty weight as the 182Q before conversion. He warns of the importance, as part of the conversion job, to remove the windshield and completely reinstall it with new seals and glue, because a slightly loose windshield gets in resonance with engine rpm and creates a vibration that must and can be eliminated. He reports a cruising speed of 144 Knots at 12,500 ft. At 8,000 ft, best cruise altitude of the basic 182, the cruise speed is exactly the same, which was demonstrated when two 182, one of them with the SMA conversion, flew the Atlantic together on their way to Oshkosh and back; but that the climb rate of the 182SMA was distinctly superior from MSL upwards. posted at 10:11 AM News of September 09, 2007Answering a frequent question regarding biodiesel fuel for aircraftAn example of questions we receive is this one from RTD in Pace, FL: 'I enjoy the newsletter very much and I have learned very much. I have an unanswered question about fuel. At least one manufacturer (I forget which one) says that BIODIESEL fuel is not approved. Why would biodiesel not be approved? Is it because of quality control issues? Or what?' DieselAir Newsletter answered: An aero diesel engine is certified for a certain fuel, typically JetA. That fuel is a certain formulation of kerosene. Calibration of the engine to a fuel consists in taking into account the density (weight per gallon), the caloric content (which gives the rated power), and the viscosity. To adapt a diesel engine to a different formulation of kerosene, in the most complex case one must: Change the setting of the injection pump, to have the right amount (weight) of fuel per injection stroke for the max. allowed power, Change the nozzle, to fit with the viscosity and still obtain the right size of droplets of fuel in the mist generated by injection. This is never very difficult. For example, some aerodiesel engines can shift from motor diesel to JetA and back with one switch of a control. Now here come the problems: If you are flying from A to B, you expect to refuel your plane at A and B. With JetA this is easy: It is the most universal aviation fuel. With Avgas it is relatively easy but getting tricky in certain areas. With biodiesel, there is none available. Your engine, to use a different fuel, must be STCd again. Here comes the FAA with a test program, at a cost. So what will happen is this: Biodiesel will be added to JetA, according to a formulation producing same density, same caloric content, same viscosity. Oil companies know how to do that. FAA will cooperate. Also engine manufacturers. FAA and JAA will have conventions to reconcile their certification processes. There will be a lot of testing, and of disagreements regarding test results. Meanwhile oil companies and farmers lobbies will resist on the grounds that biodiesel is more costly to produce. Politicians will have their say, according to whether their constituents are oil companies or farmers. This goes for foreign countries too. It will take years, and zillions of dollars (most of it to consist in legal fees.) But it is going to be FUUUN... And in the mean time you will fly your aerodiesel with JetA, and already save a lot of money and gain all kinds of advantages. posted at 2:38 PM The D-Air 100 aerodiesel acquired by Howell Aero EnginesDiesel Air Limited (nothing to do with the DieselAir Newsletter) based in Buckinghamshire, suppliers of the DAIR-100 compression ignition light aero engine, are pleased to announce that they have reached an agreement with The Howells Group Plc., a long established engineering company based in Manchester, to manufacture the light aluminum aerodiesel 2-stroke engine. The engines will be produced by Howells Aero Engines Limited - a subsidiary of The Howells Group Plc - and marketed as the HAE-100. The company is well on its way to manufacturing the first production batch of propulsion units they hope will revolutionize the light aircraft market, and notably the LSA market in the US. At 100hp the lightweight liquid cooled diesel engine provides enough low end torque to power the fixed pitch propeller more commonly used on the 100hp Continental 0-200 and Lycoming 0-235. With easy retrofit capabilities and single lever control, the HAE-100 unit is also well suited as an upgrade in many popular flying school singles. Clearance for Public Transport use on training types such as the Cessna 150, will follow on completion of CAA/EASA and FAA certification trials. With running costs which are a fraction of operating on AVGAS, the HAE-100 not only offers substantial fuel savings, but will extend the useful range of any retrofitted aircraft by around twenty percent. The diesel engine will run on bio-fuel and Jet A-1, making HAE-100 powered aircraft the ultimate green flying machines. It is anticipated that the first production units will be available for (UK) PFA use late 2007, at a cost of under £15,000 (plus vat if applicable). A conversion kit for the Jodel range of aircraft is already underway, with other popular makes to follow in due course. Howells Aero Engines have commenced manufacture of the HAE-100 diesel engine for PFA (UK) types. Visit: Howells Aero Engines Ltd, Sharston Industrial Estate, Longley Lane, Wythenshawe, Manchester, M22 4SS, United Kingdom. Tel: +44 (0)161 945 5567 Fax: +44 (0)161 945 5597 E-mail: info@howells-aeroengines.co.uk For background information on the engine see The Diesel Air web site http://www.dair.co.uk (Howells Aero Engines website, 9/07) Comment: In the long term, the opposite piston, 2-crankshaft 2-stroke design seems the most promising one for aero-engine applications: It still holds the world record for energy efficiency (specific fuel consumption or consumption per HP-hour), established in the late 30s by the Junkers Jumo 600HP engine of Germany. It is also a light design, most favorable for engines of less than 150HP or so. posted at 2:17 PM |
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