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Hey Philip: Checked in with you in the past about your perspective
on some things. I own a DA 40 --08 model. Am curious whether you
still fly the Cirrus and what your current perspective is on that
vs. Cessna 350/400 and 182 for personal use. Understand a turbo
would be desireable for different missions. Am really interested in
thoughts on the different characteristics of each aircraft. Thx.
Tim Gleeson

-- tim gleeson, September 8, 2009

Answers

I flew the Cirrus about 1.5 weeks ago to help a friend pick up his daughter in Upstate New York. We saved about 10 hours of driving with a 2-hour round-trip. I loved my demo flight in the Cessna 400, but the market has spoken and the Cirrus SR22 outsells it hugely. Unless we assume that all buyers of SR22s are stupid, there must be a bunch of things that make the SR22 a more practical machine.

A turbo is desirable if you want to experience engine failure, decide between heroic airmanship and the parachute, etc. Remember that when the turbo fails it will usually take all of the engine's oil with it. If I lived in Colorado I would probably look into one.

If you're patient and want to carry a bunch of bulky luggage, the C182 is tough to beat as a family airplane. Certainly people buy it and fly it for 30 years, which they don't do with the DA40.

In this economy if you want a modern airplane I think that a used SR22 is the best value. I kind of like my SR20 because the design has a balanced nature, but for the $280,000 that we paid for our SR20 you could buy a lightly used SR22 today plus a few years' supply of Avgas.

-- Philip Greenspun, September 10, 2009


Responding to Eric, below....

It isn't meaningful to compare the safety record of a 185-knot Cirrus SR22 or a 225-knot Cessna 400 to a 125-knot Cessna 172. The Cirrus or C400 pilot may go 800 nautical miles in one flight, punching through multiple fronts and weather systems. The C400 pilot might be up at 25,000' where severe weather is truly severe and it can take a long time to land. A Cirrus accident in July involved a pilot who became incapacitated at 25,000', presumably because his oxygen system failed somehow (the plane ran out of gas over West Virginia and the pilot was killed). That is not a risk in a C172. If you restricted an SR22 to the same kinds of trips that a C172 typically does, e.g., 1-hour day VMC with a CFI on board half the time, the safety record would improve quite a bit.

As for turbocharged engine unreliability, I would recommend that Tim talk to any of the mechanics on his local airfield. The first Cirrus SR22 engine failure that I heard about was one of the new turbonormalized models (pilot deadsticked it into Reno, NV). The turbocharger failed, the oil leaked out, and the engine stopped. The Piper Malibu/Mirage engine has two turbochargers and if you go to a Malibu owner's convention something like 1/3rd of the audience will raise their hands when asked "Who here has experienced an engine failure."

Piston engines are at their most reliable when used at moderate power settings, with no extra hardware plumbed into the oil system, and flown low enough to ensure enough air molecules flowing over the cylinders to provide adequate cooling.

-- Philip Greenspun, September 13, 2009


Tim's follow-up question below: As I think I noted in my first reply, I love the Columbia's handling. I thought it was more responsive and natural to fly than the Cirrus. Not because the Cirrus is a side-yoke and the C400 is a side-stick, but just because of the harmony of the actual controls. As a practical matter, though, unless you have infinite money you'd be crazy to buy a new airplane right now and used SR22s are incredibly cheap and plentiful. The Cirrus build quality is good enough but no better. Think "Chevy Malibu".

The DA42 was designed for multi-engine training and works great for that mission, according to some flight schools that I've talked to. But it isn't as comfortable or roomy inside as an SR22, so very few private owners buy one. If you were going to fly around the Caribbean every week the DA42 might get more appealing. Even if the engine had worked as originally planned and the manufacturer hadn't gone bankrupt, there are annoyances to operating with an unusual powerplant. You can get a Cessna 182 or SR22 fixed at almost airport in the U.S. Try pulling your DA42 into a small airport's shop, though!

-- Philip Greenspun, September 13, 2009


Tim and Phillip

Regarding the safety of Cirrus and Cessna 350/400 it looks like they have a much worse record than Cessna 172/182 and Diamond. According to the stats: Cirrus and Cessna 350/400 are involved in fatal accidents at about 3 times the rate of Diamond and Cessna 172/182 aircraft. If these are your 3 choices, my preference would be the 182 Turbo for speed, safety and comfort. If you want the ultimate new- production traveling machine, wait for the DA50 Superstar.

This graph is from the diamond website under "why diamond," and "commitment to safety": http://www.diamondaircraft.com/_images/chart_safety01a_large.gif The statistic is Fatal accidents per year for 1000 of a specific model of aircraft flying. I think this measure is easy to determine and useful in determining the safety of a specific model of AC.

You can calculate these stats on any aircraft using the FAA registry: http://registry.faa.gov/aircraftinquiry/AcftRef_Inquiry.aspx and the NTSB site: http://www.ntsb.gov/NTSB/query.asp First determine the population of a specific model as registered with the FAA. Then compare this number to the NTSB Query search Fatal accidents in a years time frame for that particular model.

Phillip's claims regarding the risk of flying a turbo'ed aircraft, in my research, are unfounded: "that you should fly a turbocharged aircraft if you want to experience an engine failure" and "a turbo failure will normally cause the engine to loose all of it oil."

A well maintained turbocharged aircraft that is properly operated is a very reliable machine. I'd sure like to see the data that supports Phil's comments.

I fly a TU206G and decided to research this model a bit for accidents in USA over the last 5 years. Here are some findings: 1. In the USA, there are 881 (Turbo and nonTurbo) 206G models flying, with 40% being TC (turbocharged) and 60% being NA (nomally aspirated)

2. Over the last 5 years there were a total of 30 accidents of these planes. Only 3 accidents were due to engine failure. One was a NA engine that had a crankshaft failure. Another was a TC engine with a blocked oil passage to the #5 crankshaft journal leading to no lubrication and subsequent engine failure. The last was a TC engine with oil starvation due to a fracture of the oil pump drive shaft. None of these involved a turbo related failure.

3. There were a total of 5 fatal accidents in the group. No fatals due to engine failure. 4 were due to IMC flying and one a powerboat passenger who was hit by a float equipped 206 during takeoff.

Does flying a turbo'd plane mean you are going to suffer an in-flight engine failure at a much greater rate than comparable NA engines and have a fatal accident? Not in my opinion. The stat's do reliably show that Cirrus and Cessna 350/400 are involved in 3 TIMES as many fatal accidents vs a 172/182 or Diamond AC per 1000 planes flying. I don't see any rational reason to suggest a turbo creates a significant safety risk.

Again I respect Phil, and have flown with him in his R44 and had a ball. I also have enjoyed and gained a great deal of info from this site. Thanks for the useful and inspirational resource Philip.

-- Eric Whiteman, September 13, 2009


Thanks for both answers . While I have no hard info on the relative reliability of turbo vs. na engines my AME has commented on turbos as per Philips point. I agree the accidents stats must be drilled down into for perspective lest they be tortured into saying whatever one wants. Philip I will say that both of the men I have had as instructors to date have preferred the Columbia to the Cirrus. Both commented on the build quality and neither liked the Cirrus stick. Would welcome comments on that and here's another thought. What about throwing the DA 42 into this discussion as they are particularily easy to buy right now.

-- tim gleeson, September 13, 2009

Given how this is one of the most fundamental questions you could ask in aviation, reliability of turbocharged vs. normally aspirated piston engines, it is really astonishing how hard it is to come up with reliable statistics. So far I have not found anything in the FAA, AOPA or GAMA websites. Nor do Lycoming or Continental proudly announce conspicuously on their website the failure rates for their engines. As for turboprop aircraft it is easy to find claims of failure rates as good as one in six million hours. Something about an engine that can glow red, is vulnerable to shock cooling, has a low TBO, will invariably need a top overhaul, does not make it the best choice for anyone who wants to cruise along in the sky worry free. If you do have an engine failure in an SE aircraft the fatality rate is one in ten. [It will be interesting if Synthetic Vision results in sharp reduction in that figure.] Although out of vogue, a turbo charged engine might make sense on a multi-engine aircraft. The common belief is that you are no safer in an ME aircraft than a SE aircraft. In the 2008 Nall Report they found the fatality rate in the case of a dual engine failure in an ME aircraft is 50%. No one has statistics on how many ME aircraft make it back to the airport on one engine. What�s important to realize in high performance aircraft, whether ME or SE, is that for every knot increase you increase the energy on impact by four times. Just like in an auto, your survival rate is many times higher in an accident at 40 mph than 80 mph � a major reason Cirrus can�t get their accident stats down despite all the other advances in the plane.

-- Richard Miles, September 13, 2009

Phil's assumption is that a pilot flying a turbo powered plane is at a significant risk for an engine failure because of the turbo. Yes they may have a bit more expense at the shop, but they are not failing, blowing oil out the side and causing crashes at a significant rate, as he asserts. Tim I say get the T182 if you want a fast, safe, comfortable, new-production traveling machine. I like the turbo because I fly in the west and I depart from 7000 feet MSL.

Phil's says the Cirrus has poor safety stats because it is being operated in a more strenuous and dangerous high altitude and cross-country environment. He then alludes that I unfairly compared (in my earlier post) these cross country AC to the slow, "one hour VMC with a flight instructor on board half the time" Cessna 172 (FYI the Cessna 182 and Turbo182 were also included in my previous posted stats).

In the USA there are 1,341 Turbo 206's. For all these Turbo 206's flying over the last 5 years there have been 5 fatal accidents, not one fatality due to an engine failure. Using this population and these accidents it gives us a fatal accident rate of 0.75 per 1000 Turbo 206's per year. These planes are operating in harsh backcountry, commercial bush operations and high altitude cross country fight with much better safety than the Cirrus or Cessna 350/400. This rate is 0.73 for the Turbo 182.

Do turbos add additional cost to maintenance and overhaul? Likely a bit, but they also allow faster speeds, higher altitudes, faster climbs and better High DA performance which helps safety. And I'm definitely not saying they are for everyone.

Do turbos cause an statistically significant risk of crashing and dying? Not in a Cessna 182 or 206, according to the last 5 years of stats. Sorry about the long post, but turbo planes get a bad rap from Phil in regard to safety, while the Cirrus with the "magic chute" is involved at a much greater rate with unfortunate, unnecessary fatalities.

Safe flying no matter what you choose!

Eric

-- Eric Whiteman, September 14, 2009


Comfort is HIGHLY subjective. Take no one's advice on this. For instance, there is no plane I have tried where I am more comfortable than my Ovation ( at least in the pilot's seat). OTOH, getting in and out is tough for me. If I were flying shorter flights, I would prefer diamond aircraft. Cirrus and Piper and Beech all penalize me for long legs and fit body. If my legs were shorter, or I were fatter, they would fit better. Cessna is okay, and the Columbia would work well. None of that info will help you unless you are just like me.

-- Eric Warren, September 14, 2009

I agree with Eric Warren - "fit" is entirely subjective, and can only be determined by sitting/riding/flying in a variety of airplanes, with due regard to the mission, long before the decision to purchase. More to the point of turbo vs normally aspirated, I wholeheartedly agree with Eric Whiteman -- "turbo[charged] planes get a bad rap from Phil in regard to safety, while the Cirrus with the "magic chute" is involved at a much greater rate with unfortunate, unnecessary fatalities."--

Turbo-charging is advanced performance. If you're not ready for that, don't go there. However, if you're willing to take the time to learn the characteristics and operating considerations of a turbo-charged airplane, and your mission requires sustained climb performance (whether due to terrain or weather), and you're willing to adopt a zero-tolerance attitude where it comes to maintenance -- you may have found your dream airplane. While turbo-chargers have their Achilles' Heel (namely, high temperatures), proper operating practices and maintenance can all but eliminate extra risk. Again, if the mission requires turbo-charged performance, your diligence is a worthwhile trade.

-- Jane Carpenter, September 15, 2009


Really appreciate anyone who makes an effort to wade through the individual accident reports the FAA publishes and the trends with the Turbo 206�s are encouraging in terms of engine failure rates. Seems it used to be easier to find this data tabulated and summarized and wonder why the FAA does not make the effort to do so, why they are �flying blind� about TC engine failure rates. When it comes to crunching numbers that deal with human fatality rates I am inclined to not count on any conclusions unless you can poll a sample of at least 300 or 400 out of a population of tens of thousands or more. We will probably see Diamond Aircraft�s accident rates fall in line with that of Cessna as laws of average play out. In hopes that EASA would have some clue as to how safe TC engines might be I thought I would try getting a response. I was really caught off guard at how cavalier the agency has been in admitting they have no such information or that they should have any data. It would be interesting to know the total fees paid to EASA by engine manufacturers for certification. Like anyone, I would like to think I could handle flying a turbo charged Mooney M20M and cruise along at 250 mph. (I have got as bad a case of Tom Cruise, Maverick, macho pilot syndrome as anyone). But I do not want to depend on a policy of total vigilance � too much happens in a cockpit, especially in IFR. Nor am I confident that following a rigorous maintenance schedule is going to be as effective as common sense would make it seem. At a minimum I would not want a TC engine without a FADEC. We should be able to obtain conclusive evidence about TC engine reliability and think the regulatory agencies should be able to readily provide that information. There does not seem to be much interest in political activism these days among pilots, but we would have much better, safer, faster, reliable planes if we could get the establishment to expand the LSA style of regulation to all general aviation aircraft with gross weights up to 12,500 lbs. Just compare the cost of certified vs. experimental avionics equipment to see that the governmental cut is more than just a pound of flesh. From a theoretical standpoint a turbo prop engine is a simpler design than a piston engine. We really need to take a hard look at regulation and that an unintended consequence is that innovation is stifled. Lycoming and Continental are looking at a huge expense to develop a new engine and have to worry if it will be certified, how long it might take, and if they will get stuck with some arbitrary restriction that makes them less competitive in the market place - as has the Austro engine where TBO/TBE is 1,000 hours. Given how many decades that turboprop technology has been in place there should be a $50,000 turboprop engine in the market. If safety is really what the FAA or EASA is about, if we are going to have regulation, there should be standards, we should be seeing engine failure rates in the millions of hours, not hundreds of thousands of hours.

-- Richard Miles, September 17, 2009

All turbos are not created equally.

First, turbo normalized engines are a great compromise, and I would encourage everyone who really wants a turbo to consider this sort instead. Normalization is easier on every other component in the aircraft, including the pilot, while offering almost every benefit of the traditional turbo except performance at low levels which very few missions actually call for.

Second, newer engine designs and builds are better at handling the boost. I am much less concerned about a turbo 550 than I am the designs from some of the seventies models.

Lastly, if a design needs a lot of boost just to get off the ground, that's not the plane for me. If you actually need that sort of thing, and are willing to pay for the maintenance with time and money, then it's fine for you. Those who think it's a free lunch will be lucky to lose only money.

-- Eric Warren, September 18, 2009


Philip: One aircraft missing from this discussion might be the 206. Any thoughts on the pros/cons of a 206? Tim

-- tim gleeson, September 29, 2009