I will agree that certified engines are dinosaurs of technology. Hell, the Germans had fuel injection on the Me-109, and the FW-190 had automatic mixture in WWII!
I get the fixation on magnetos - if all else fails, they keep generating spark as long as the engine is turning; however, electronic ignition has been around for quite awhile and is pretty darned reliable.
The problem with diesels in GA is weight. Horse for horse they're a lot heavier than gasoline ones.
The opinions and statements of this poster are largely based on facts and portray a possible version of the actual events.
Well when it comes to technology in our piper Cherokee-challenger, we put in a Garmin GTN 650 and STEC 30 autopilot last year. Just got IFR rating in November after 7 years VFR only. Just recently we were supposed to fly from Charleston SC to Columbia SC on July 3rd and of course the entire east coast, at least it looked that way but definitely SC was littered with thunderstorms all day. My wife really wanted to get to Columbia to see her brother so when another family member indicated they were driving to Columbia for business she rode with them and I waited until the next morning, July 4th to make the flight. The 4th of July morning at 7am finally no thunderstorms but a 400 foot solid overcast at Columbia. the lowest approach I have done in actual was the 800 feet at Easton MD during this summers flying trip from MI. Since Columbia has an LPV approach to runway 11, I departed. Was IFR for last 30 mins of flight and I ask for the full RNAV 11 approach. It was solid IFR for the entire approach and broke out on the approach at 480 msl just as I was about to go missed as mins are 436 msl and I decided I would go missed at 460. The RNAV approaches are great was lined up perfectly with the runway and right on glide slope. Just before breaking out I started to see the ALSF-2− Approach Light System with Sequenced Flashing Lights through the clouds. Having never seen the lights in actual conditions, it took me a few seconds to realize what they were. I am still amazed that it works so well. I think it is good that My wife went ahead the day before as I am not sure I would have tried my first real approach to minimums with her in the plane. It was a great learning experience and it was good to not have to deal with thunderstorms like we have for the first few weeks of our trip. The LPV approach minimums on the RNAV 11 approach are 436 feet MSL which is 200 feet above ground level. So I was about 240 feet above the ground when I broke out. Just enough time to put in remaining flaps and slow for landing.
I would not have been able the comfortably make that flight without the new technology. I love flying VFR but the new technology avl to GA has allowed us to also count on our plane for transportation as well as just for fun. I do not believe I need any more technology in the plane but am thankful for what I have.
States visited with my Piper Challenger
OK guys!,
In addition to the AOPA article on the DA42-VI, the next few pages cover the whole diesel engine and it's recent history. Frank is spot on regarding weight and when you get down below 150HP the weight burden cancels out the fuel savings. That article has some interesting insights on the future growth being most likely in the 3rd world and big opportunities in China and India. Here is the USA we have too many small aircraft powered by 100LL and a lot more airports. The 2nd generation diesels are aimed mostly to address overseas markets. In some parts of the world 100LL runs $22/gal vs jet-A at $8! Plus 100LL is really hard to find compared to Jet-A.
Joe
First off, I'm using IE 10, which won't allow carriage returns on these forums, so I'm not really stupid about not breaking up the paragraph. I retired two years ago as a software manager for a very large aerospace company that makes the fighter aircraft our forces are using, have been using, and are about to start using. (nuff hints?). So let's just say I'm comfortable with technology. I still prefer to fly analog-equipped planes. Why? Because when I'm on short final, I can glance down at the airspeed, and I don't have to interpret a number - the relative position of the needle tells me if I'm too slow or not. That said, when I built my Sonex, I went with an EFIS. Why? Because when I calculated the cost of all engine instrumentation, flight instrumentation, nav, GPS, etc., the $$$ cost was more than a new MGL one-box solution. Not to mention the weight savings. And, now that I've been flying it for a year, I have to say that it's now just as intuitive as the old analog systems. And this system does FAR, FAR, more stuff than my '67 C-172H could ever do.....
Quite honestly variable valve timing is not that much of an asset to a NA aviation engine as we know them. Fuel injection is a performance advantage, but not reliability from my perspective. Ignition timing....there is something there, but again an aviation engine runs such a narrow speed/load range that there is probably little to gain. Unfortunately little to nothing from the auto world translates over to how an aviation engine operates, and so is of little use other than impressing people who dont understand it.Originally Posted by mustangbuilder
Lets peel that back David. China already owns Continental, Continental had been developing some other aerodiesels before China bought it. China plans to build up GA in China, China does NOT want to screw around with 100LL, Now add Thielart to the stable. Thielart owns some US STCs as we speak.
A decade ago,some guy landed in the Paris area and needed to top off with 100LL. None in the area. Zero. Nada. Paris airports are awash in aviation kerosene. He had to find some jerry cans and drive out to the countryside to get his 100LL. Living in the USA is great.
As for that Rotax. If you represented the FADEC technology spectum on a wall chart a yard long, the Rotax 912is would take about an inch on the left side. Its not quite up to a '98 Corolla. Still, an 18% improvement in fuel economy is nothing to sneer at. The dual carbs are gone and they remind me too much of tunning an old MG. Everyone should own an old MG at least once .Find out why Lucas is called the prince of darkness
My measly experience in FADEC turbines was a non event. If I ever got an error msg on run up, I just re-booted the a/c and it cleared. If I wanted to see their dark side, it had to be in a sim. When the blue lights come on, carefuly set your coffee cup down and flip the switch from auto to manual. Expect a little throttle lag. Big whoop, deal with it.
Carl, I'm with you. I always catch myself doing t.o and landings on the standby steam gauge. I shift to the AS tape on the EFIS after gear up. I guess that I'm just untrainable.
Bob
This is interesting. If we look at the big 2 in aircraft engine manufacturers, they offer a range of engines from 65 to 400 hp that have been used in all kinds of GA aircraft as well as homebuilts. Looking at their "Installed base" and the whole certification thing it seems to me that applying new technology is restrained by cost and return on capital. They have "scaled" their business to engine replacement and overhaul which is where the money is in relation to sales of new production aircraft for a least the last 20 years. Both C & L have worked on diesels and C is investing in a 2nd gen diesel for the export market. The only real innovation in small aircraft engines is Rotax, but I would say the Cont. 240 did try with a FEDAC version...it didn't catch on in our world since it's competing with cheaper to buy old engines. Homebuilders still can opt for auto conversions, but given the shift from "scratch built" to kits, this has become a small market as well. I'm hoping something "good" will come out of the recent D.C. noise about re-visiting certification requirements. If they'd cut the hassle, cost, and time to comply maybe we'd see some movement in STC's for upgrade kits for some of these old engines, and provide a more economical path for the big 2.
Joe
Part of the reason that diesels never "caught on" in this country was political. TEL was a big business both here and in europe through the anglo-american oil company. Actually it is a familiar story that is re-playing with the corn growers and ethanol. Anyway.....thats part of the history. There were american production aero diesels, from 90 horse (prototype) through 400 I believe. Unfortunately by the time you get a decent power/weight ratio from the diesel cycle, the complexity has seriously reduced the engines durability and reliability. Part of the reason that we still see big simple engines, is because that is what works, works well, and keeps working. Road vehicles spend most of their time at high speed / light load conditions, with constant transients and little little to no time at full power. This is where VVT, VVL and direct injection really can shine. In applications where the duty cycle is higher, and most time is spent at 75% power and above, there is little to no benefit in this technology. There are even cases where fuel metering upstream has benefits ( i.e. TB injector or carb ).
Maybe my thought pattern belongs elsewhere. I'm looking at this thread, keeping in mind that the subject, in part, is the diesel powered Diamond DA42, not as a craft that is being purchased to chase that $100 hamburger or to fly around the patch or maybe to the FBO a couple of parishes west. I would think that this particular Diamond buyer is going to be doing a LOT of cross country flying. And with that, the ability to fly IFR on occasion so that the pilot/passenger(s) aren't stuck somewhere. And doing this in a twin that is sipping about 11gph of Jet-A which is less expensive than 100LL.
As far as the Rotax FI engine goes, it may not be far on the overall engine evolution scale, but the planes that have it don't have a mixture lever. So that says that Rotax is at least doing SOMETHING to upgrade their engine's capability. And the engine is very robust with a 2000 hour TBO. But I'm a non-pilot, so what do I know?
David
David,
Good Points....however there are times I prefer to have the ability to control mixture. At one point in our history, we were smarter than the machines we ran, now for the vast majority of people the exact inverse is true. Ask the fellows that tried landing over in San Fransisco a couple weeks back.
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