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Old 2nd July 2008 | 23:24
  #42 (permalink)  
SNS3Guppy
 
Joined: Oct 2005
Posts: 3,218
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From: USA
60 out of 60 recoveries even under test conditions is not bad going. Moreover we have no evidence the spin drogue was used in a single recovery. In fact I think we can be pretty certain it was not.
You can be "pretty certain" based on what? How many spins total were conducted? Do we know? We do not. We know of 60. How many departures occured in which recovery was not satisfactory, or or how many maneuvers were repeated in the process? If a test program consisted of just 60 spins to investigate spin characteristics, then it was a pathetic test program, indeed. 60 are cited. You make the assumption that this is all. Only 60 are addressed, and from this you draw the conclusion that only 60 were conducted, and therefore were all successful...and state we can therefore be "certain." Assumption is a dangerous thing in this business. You can be "pretty certain" based what, exactly?

Your certainty is irrelevant and meaningless, of course, because no matter how "certain" you feel, both the FAA and Cirrus Design determined the aircraft cannot be spun safely, that it may become unrecoverable, and elected to provide a backup means of recovery in the form of the caps parachute system.

I agree the testing was not as comprehensive as required for an aircraft cleared for spinning. However you appear confused later by what constitutes a guarantee. More comprehensive spin testing does not guarantee a pilot will always recover from a spin. It strongly suggests that a competent and current pilot will do so.
Guarantee? The aircraft is prohibited from spinning. There was no comprehensive testing. The aircraft wasn't spun; it was tested for recoveries before the spin turned into a spin. The testing in the case of the Cirrus does NOT, repeat NOT suggest, strongly or otherwise, that a competent and current pilot can recover from a spin in the SR20 (or SRXX) at all, and to suggest as much is a dangerous statement to make. It suggests that the spin entry may be arrested if the proper technique is applied at the incipient stage, strongly suggests that spins should be avoided, and states quite clearly that spins may be unrecoverable.

In EASA land if the aircraft enters a rotation if there is sufficient height the evidence would suggest that almost certainly a standard spin recovery will work and if it does not the chute should be deployed.
No, again, it does not. It suggests, and without certainty, that a spin may be prevented by exact recovery in the incipient phase. Even in the magical EASA kingdom, where the same rules of aerodynamics apply, we are told that the aircraft in a spin may become unrecoverable. You can show the movie in a different theatre, but it's still the same show, even with subtitles. There is no evidence, none, not even a suggestion, that recovery is any certainty or that standard recovery will certainly work...just strong wording that it's not approved, and barring your sudden entrance into the qualified world of test piloting, that's as far as it goes. The spin may become unrecoverable. That's all anyone really needs to know. Advertising or suggesting otherwise is a dangerous, and foolish thing.

Both the 152 aerobat and Tomahawk are cleared for spinning. Both can show peculiarities. I have never experienced these in the 152 but in the Tomahawkthere is nearly always a pronounced tendency to roll off one wing. It is not an issue but AOPA identified that the aircraft has been involved in more fatal spin accidents that the 152. Sensibly they also concluded that there is "nothing wrong" with the spin characteristics but the type requires additional training.
Ah, the Traumahawk. There's a subject for another lengthy thread, isn't it? An airplane that had to be recertified because of it's history, an airplane which went into production with a different wing that that with which it was certified, and an airplane which can spin 600 times and recover, but on the next become unrecoverable because of dimension changes within the airframe during the spin under loads...has no comparison to the 152.

Spins are an extremely complex aerodynamic subject. If you want to have a protracted discussion about the nuances of spinning an airplane perhaps a separate thread here, or better in the technical section would be appropriate. That will take us very far from the appropo use of the ballistic parachute, which is the intent of this thread.

You are confusing two totally different concepts. Whether the pilot is the most dangerous component has nothing to do with whether most pilots are fools.
It has everything to do with pilots who are fools. Pilots acting foolishly play the fools game, whether it's controlled flight into terrain due to lack of situational awareness, blasting into a thunderstorm over mountains at night in the hopes that a parachute of all things will save you, running out of fuel, or your illustrious example of flight out over cold water without the proper preparation on the basis that it's a "small risk." Foolish behavior, pilots acting foolishly, and clearly the domain of a fool. That such behaviors are dangerous go part and parcel with the title. Call a spade, a spade. A fool acts foolishly.

Your evidence is?
Evidence of a negative? Absurd. You made the statement, you back it up. Most spins occur at low level? Why is this?

Personally, I've spun many times. I don't do it at low level. Do you? Your assertion that low level spins are fatal, followed by the assertion that most spins occur at low level leads to some interesting conclusions. Most spins, therefore, are fatal, if they occur primarily at low altitude and are always fatal. Are we to believe that aircraft are rarely spun, or that record numbers of fatalities are occuring from spins?

Departures from controlled flight, including spins, occur at all levels in the atmosphere. The stall-spin on a turn to final is one classic example of a low level spin, but only one scenario in which it can happen.

I spent much of my early career doing steep tight turns to stall buffet at low altitude every 30 seconds or so, at 75' above the ground, all day long. Never spun doing it, though. Conversely, I've entered spins at higher altitudes and recovered under various circumstances, controlled or otherwise; I've no need to prove where or when they occur, but perhaps as you made the assertion that A)low altitude spins are always fatal, and B)most spins occur at low altitude, you do need to back it up. Fact is there are a lot of spins done out there ever day that aren't fatal, and a lot more spins performed than there are fatalities from spinning...so your assertions are clearly in error. You figure out where.

[QUOTE]Every time you get in an aircraft there is a component of risk. If you don’t accept that, you would certainly never fly a single.
[QUOTE]

I hear that a lot, and it's the neanderthal bark-at-the-moon mentality which demands we accept risk. "Must accept risk, must accept risk!" No, you mustn't. No matter how much you desire to do so.

You preflight an airplane to prevent taking that airplane aloft with missing nuts, bolts, cracks, parts, oil leaks and drips, etc. You calculate takeoff distance. You ensure you have a place to land if the engine fails. You learn your checklists, procedures, and are prepared for such eventualities that may occur from an engine fire to an instrument failure. You prepare. Is there a "risk" of an engine failure on takeoff? Not a risk if you have somewhere to go, any more than there's a risk of a brake failure while taxiing if you keep your speed reasonable and within limits, and never point the airpalne somewhere you can't get it stopped. The risk is eliminated.

Mitigate, eliminate, avoid, whatever it takes to make the "risks" and hazards non-issues. Got just enough runway for the takeoff? Lose some weight, fly when it's cooler, do something to make it safer. Have two passengers drive to the next airport, takeoff, then go pick them up where there's a longer runway. You're eliminating that risk by opening up your performance, increasing your possibilities. Now you have extra runway. Plan ahead. Accepting risk is wrong. Managing it is accepting it; that's wrong. Find it, eliminate it. That's right, and yes, it's possible.

This closed-eye mentality that there's risk in everything, so accepting it is okay, is a poor approach to aviation, to life, really. So many go through life blindly that they simply accept it, and it's not necessary to do so. Don't wear safety goggles...the "risk" of an object flying off the grinding wheel and striking your eye is small, right? Small eye, big space in the shop? Of course not. We eliminate that risk by wearing the eye goggles. And so it goes. Why look for traffic in flight? Small risk; it's a big sky, two small airplanes, right? Two medical helicopters collided for the first time in US history recently, in Flagstaff, AZ. Occupying the same bit of big sky. In fact, the first automobile collision occured when there were two automobiles on the face of the planet...and they ran into each other. Small risk? There's no such thing.

The risk of an engine failure at night in a single is very small.
No, it really isn't. This is the mentality of one who has never had an engine failure, probably never landed off field, and doesn't appreciate the concept beyond a simple training exercise done in the comfortable presence of a flight instructor over a hard surfaced runway. It's still academic, the eyes haven't yet been opened. It's a "it could never happen to me" thing, still. No, it's not a small risk, but you think it is because you simply don't know yet. Once you've experienced it, you may begin to believe differently.

You have the same "risk" every time you go fly, of that engine failure. Either it will, or it won't. You can try to drag statistical analysis into it and skew the view, but it doesn't change the fact that at this second in time, either your engine will fail, or it will not. Now, a second later, either it will, or it will not. And this never changes, every second of every flight. To suggest it's a small "risk," and therefore not an issue, to dismiss it lightly, is to act naively and in ignorance, and one might correctly therefore assert, foolishly. Yes it will happen. It's never a matter of if, but when.

I've said that for many years, and every once in a while someone will come back to me and we'll talk. They've finally experienced that inflight emergency, that failure, and they'll tell me that they made light of it for so long, too. They ridiculed the concept, it was academic to them. But no more. Now they finally take it seriously. You should too. Far better to learn now, than in real time when it's happening. It's not a "small risk." Plan accordingly.

I think for reasons I don’t understand you have a bias against the Cirrus and are not therefore prepared to rationally consider the evidence or concede on any issue.
You think incorrectly, of course.

I've long been a supporter of Cirrus, long before they began selling production airplanes, and I was a supporter and admirer of the VK30 when it was still a plans-built offering in the experimental market.

The presence of the parachute on the current offerings is a gimmick designed to sell, and included for certification. It tends to lead inexperienced and unwise pilots to do stupid things, and then pull the panic handle. One should never do something in the airplane that one wouldn't do without the parachute, but amazingly, pilots continue to do so. That not every incident results in a deployment or a fatality is irrelevant. God watches over fools, much of the time. Until even He can't do much for them, and then they pull the parachute and take their chances.

You have formed an entrenched view on twins and in spite of the comments on here by some very experienced pilots your mind is closed to any other view. That is a real danger for a pilot. I don’t mean to give offence because we are all guilty of entrenched views, and it sometimes takes a third party to point this out to us.
Really? What entrenched view is that?

Are you referring to prior comments regarding safety and the number of engines? Adding engines isn't for safety. It's for performance. This isn't an "entrenched view," it's a fact. That more engines does enhance safety is also a plus, but not the primary purpose for having more engines. I've been in four engine airplanes with one out and couldn't hold altitude...did having three grant some particular level of safety that a two engine airplane or a single wouldn't have had? Not really...now I was going down at a higher speed and a much higher weight...but still going down because I couldn't hold altitude on three. And unlike a single or a light twin, didn't have the option of sliding to a stop in a parking lot or on a highway somewhere. Entrenched view? No.

The foolhardy view is that a light twin, for example, is safer because it has two engines. It does offer advantages, but it also offers disadvantages. Dick Collins worked very hard to change public perception several decades ago in that regard, and to get people to take seriously the pitfalls of light twins. Until that time, pilots and the public did regard (more by tradition than anything else) the twin as safer, because it has that extra engine, you see. However, Dick undertook a near-one-man crusade to convince the flying general public that the other engine serves to get you to the scene of the crash, if not approached with care and caution. Hardly an entrenched view.

That extra engine will bit you, and bite you hard if you're not careful, and that's not a safe thing it all. It's there for performance, and the price of that performance is extra vigilance and training, and preparation for the time that the engine will fail (not if or might, mind you, but will and does). Not entrenched and closed minded. Just reality.
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