If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#111
|
|||
|
|||
"Dude" writes:
This stat does paint with a broad brush, but if all you are looking for is a measure of average safety in average usage by average pilots (that fly that plane) then the measure is very accurate. Yes, if you compare two models that are used by vastly different skill levels or in different types of missions, then you may invalidate the data by means of asking the wrong question. That is not being done here at all. But this perverts the nature of statistics. Even very accurate and valid statistics (with lots of data points, etc.) can never predict the individual outcome; statistics can only predict the aggregate outcome. The "average" usage by the "average" pilot does not exist, and the characteristics of that average cannot even be described, nor do the statistics predict anything about them. Matter of fact, it is easy to make the case that the average pilot does *not* scud run in freezing rain and crash into mountains; it only takes a very small handful of "special" pilots to skew the statistics. You cannot even make probabilistic predictions ("I am more likely to die in a Cirrus than a 182") because the statistics only allow this if the population is either uniform (like coin flips) or the statistics can describe the differences between individuals in the population. The fatalities per 100K statistic is completely worthless for a quantitative assessment of individual risk. It is meaningful (to some extent, anyhow) if you are an insurance underwriter, since they deal in the aggregate, but it only tells them what has been, not what will be. Unless you are one of those people who believes you are above average, then it means a lot. What makes one person who buys and flies a Cirrus all that different from another? What about comparing them to other brands of new airplanes buyers? There is no obvious difference, you will have to propose one. This is not a picky little nit type of stat. Saying that Cirrus just attracts idiot pilots is not enough, you need say why. I haven't seen a good reason yet. I don't actually think the Cirrus attracts idiot pilots, that was someone else's statement. I was trying to use it to make a point. The statistics (assuming that they pass significance tests) really tell you only that something is going on, but they can't tell you what. This is a red flag to go and actually examine the accident records and try to make an honest evaluation and decide for yourself what they mean to you. That would be true, except that examining the records tell us nothing. You should rely on the BIG RED FLAG! Seriously. If they had a common thread that was fixed, I would grant an exceptional case (aka V tail break ups). Until then, no. Um, the records tell us a lot; the statistic tells us close to nothing (other than a number.) The records tell us that some of the dead pilots were scud running in terrible conditions, and if you can honestly say that you never scud run in terrible conditions, your personal risk level is much lower than someone who does. By only looking at the single number, you throw away all of the information that might help you make an informed risk assessment. If these planes were mysteriously "falling from the sky" I'd agree with you, but the failure in most of the cases was squarely in the left seat. My point is that the stat is such a large macro that the idiot factor gets rounded out. As an average idiot, we are all more likely to die flying a Cirrus, than we are flying a 182. We are all average idiots in this stat. It is too big to slice apart that way. See above. Statistically there is no "average idiot" and mathematically you cannot make the statement that you as an individual are more likely to die. If the fatality rates were constant, you could make the statement that more people were going to die next year per 100K hours in a Cirrus than in a 182, but you couldn't say anything about your own risk. Furthermore, the fatality rate in the Cirrus is plummeting as the fleet grows, so if you want to play the extrapolation game you could predict that the Cirrus rate will be much lower this year and thus will magically become more safe than the 182. No, all you have to do is set a standard. How much more risk are you willing to take on your flight to enjoy the Cirrus over the Cessna? If its double, go for it. In my standard, I find the high fatality rate unacceptable when compared to the ancient Cessna. It should be better. That's not the same as saying it's either Safe or Unsafe. Life is unsafe, and you make your risk assessment and live it. The problem is that we are generally lousy at risk assessment, and ultimately it's somewhat arbitrary and almost always rationalized (otherwise we'd never get in a car or take a shower.) I'm probably less safe in an ancient Cessna than in a Cirrus (this showed the last time I tried to land one!) Is my risk double in the Cirrus? I doubt it. I would like the Cirrus fatality rate to be better than it is (and all other airplane makes, for that matter.) It's hard to judge whether it "should" be or not. The trends are that it will be, as the number of fleet hours is growing much faster than linearly (due to the rapid rate of delivery) but the fatality rate is not keeping pace. Those are all good, but how does that compare with the Cessna which requires a very small time of dual instruction for familiarity? Diamond? Lancair? Cirrus gets this level of scrutiny by running around BRAGGING about the safe design of their plane with a chute. In his interview I recently read, Mr. K was all about how great his airfoil is. Also, they get this scrutiny because they have high fatalites. A new glass panel 182 probably takes almost as much time to transition into safely for serious use (IFR) as does a Cirrus, though the fact that so many people learned to fly in them helps with the basic airwork. The Lancair is in the same class as the Cirrus and I would expect the transition to be at least as difficult (they're also a bit faster than the comparable Cirri and the outside visibility isn't as good.) Cirrus bragging about safety is rather premature and unfortunate, I agree with you. Well, I think the SRV and SR 20 would be better placed in the hands of more experienced folk. Since I don't see too many of those folk clamoring for a VFR only, glass cockpit, nearly 200k plane, I say they are using it to attract low time pilots. I think the days of students buying a Cirrus heve been nixxed by the insurers. It's still happening with SR20s; SR22s are pretty much impossible to insure as a zero-time student, unless you come with a lot of money and don't expect to solo for a long time. The SR22 is arguably too much of a handful as a primary trainer, though a few people have done it. The insurance people are the main gatekeepers in this case. The number of low-total-time pilots flying SR22s is probably quite small. Arguably? Definitely. You may note the 22 is doing better than the 20 in the stats. I think this is because, as I have heard from more than one low time prospective Cirrus buyer, the plane scares them. The 22 must have higher time pilots at the yoke. Yep, and a lot of people trade up to the SR22 after building SR20 time. |
#112
|
|||
|
|||
"G.R. Patterson III" writes:
You are confusing common usage English with FAA-speak. They were unable to demonstrate spin recovery because the plane will not recover from a spin. And they really tried to make it do that. That's not what the test pilot told me. Where did you get your info? |
#113
|
|||
|
|||
"jd-10" wrote in message ... I don't know why you dorks won't face facts: Self-indentification. I repeat, Cirri are for men with very small penises. Like yourself. |
#114
|
|||
|
|||
"Tom Sixkiller" wrote in message ... "jd-10" wrote in message ... I don't know why you dorks won't face facts: Self-indentification. I repeat, Cirri are for men with very small penises. Like yourself. Nonsense. jd-10 has no penis. |
#115
|
|||
|
|||
Peter,
Thanks, couldn't have said it that well. -- Thomas Borchert (EDDH) |
#116
|
|||
|
|||
G.R.,
And they really tried to make it do that. Proof? -- Thomas Borchert (EDDH) |
#117
|
|||
|
|||
Greg,
Again: Using the common method of spin recovery from a one turn spin on, say, a Bonanza, what's the altitude loss? Less than 920 feet? Much less? I wouldn't think so. -- Thomas Borchert (EDDH) |
#118
|
|||
|
|||
Jd-10,
Ha! I take your Cessnas and add A TAILDRAGGER. Anything else is just training wheels... -- Thomas Borchert (EDDH) |
#119
|
|||
|
|||
On Tue, 27 Apr 2004 09:24:57 +0200, Thomas Borchert wrote:
Greg, Again: Using the common method of spin recovery from a one turn spin on, say, a Bonanza, what's the altitude loss? Less than 920 feet? Much less? I wouldn't think so. Ya, but I thought we were talking about a Cirrus and not a Bonanza. And, I think the point remains. If you get into a spin in a Cirrus, the chute seems to be clearly recommended. To me, that implies that Cirrus has zero faith that someone in a fully developed spin is going to recover unless they deploy their chute. Please, feel free to correct. Another way of looking at this, if you enter a spin slightly higher than 1000 and you start trying a recovery, you may recover in another plane. If a cirrus, unless you deploy your CAPS WITHOUT TRYING TO RECOVER from your spin, they seem to imply you won't be around to talk about it. To me, that's more important than some corner case. It also fails to mention if "demonstrated...deployment" actually means it has slowed the craft to safe landing velocities or if that's just the altitude required to get the chute deployed and dragging air. If it's JUST starting to drag some air, I think the whole 900ft corner case then becomes a strawman. After all, I don't think a chute popping 10 feet from the ground is anything to talk about, if you're wanting to live. Also, it didn't mention what the minimum demonstrated altitude loss is for a CAPS deployment from a full spin (3-turn, right??)? Anyone know? Is it even possible? Thanks. |
#120
|
|||
|
|||
Thomas Borchert wrote:
Edr, The Cirrus cannot recover from a spin without pulling the parachute and did not do so in tests As I thought: nowhere does it say it "cannot recover from a spin without pulling the parachute and did not do so in tests". It says "has not been demonstrated". There's a subtle but important difference. Thomas, IMHO you are right and wrong. I agree that the SR-[20,22] may be recoverable from spin. The POH just says that it was not demonstrated during the certification process ( my guess is they saved time and money at that point ). In practice you do what the POH says in a situation like that. Greetings Dieter |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Boeing Boondoggle | Larry Dighera | Military Aviation | 77 | September 15th 04 02:39 AM |
New Cirrus SR22 Lead Time | Lenny Sawyer | Owning | 4 | March 6th 04 09:22 AM |
Fractional Ownership - Cirrus SR22 | Rich Raine | Owning | 3 | December 24th 03 05:36 AM |
New Cessna panel | C J Campbell | Owning | 48 | October 24th 03 04:43 PM |