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On 2005-04-25 15:37:56 -0400, Peter Wendell said:
Even a true CLT machine will only be precisely CLT at one specific load. Quite true, and as you write it is the size of the moment arm that makes the difference. The arm on an RAF is over a foot! I would guess on Dennis-era Air Commands ("classic" to use his term!) it's about six inches. In re your discussion with Stu about Magnis, I'd like to state that you just flat can't eyeball vertical centre of mass. It needs to be measured. It *is* possible to design an aircraft with a high thrustline that has little or no pitch change with application of power (I am told the SeaStar Amphibian kitplane is one such). Just like it is possible to design a fixed-wing aiircraft that requires little or no trim change when adding or subtracting power (the B-17 is one such). In both cases it is extremely difficult to do, and so it is rare. Most airplanes with a high thrustline (mostly amphibians and ultralights with high-mounted engines) exhibit significant pitch change with power. But then, pitch change can't unload their wings and cause them to flap -- not so a teetering rotor. There are lots of folks that have flown many hours in unstable gyros. Yep. Some instruct in them: basically all the RAF factory guys, plus guys in their orbit like Dofin Fritts and Jim Logan to name two good instructors (yes, Dofin got his pee pee whacked and spent a year on the beach for breaking a rule. I bet he isn't going to break that rule any more). There are also too many that didn't make it. Bingo, Peter. The fact is that we now know how to build much safer gyros that are also much easier to fly. And we don't have to give up any speed or manuverability in the process. So, there is absolutely no reason not to do it. Bingo again. See, Peter, Stu, even Dennis: if you GAINED anything from a high thrust line, you could make a credible argument that the risk was worth the benefit, that it was a worthwhile compromise. But the claims made for un-stabbed and non-CLT gyros vice stabbed, CLT ones are unconvincing. Combine this with the availability of high quality dual instruction, and there's no reason that gyros can't acheive a safety record equal to, or better than, airplanes. Well, you can lead a horse to water but you can't make him drink. We are still having guys teach themselves to fly, or almost teach themselves. Crunch. More troubling, we have had some relatively low-time, but licenced and well-taught, guys prang, some fatally. That's part of what worries me -- there's always going to be the guy who will just go fly, and he is the bane of every CFI/BFI/AFI and manufacturer's existence. That syndrome, I think, is why Dennis withheld tail rotor gearboxes (I believe that was the part) from his helicopter customers until they could demonstrate training. Both helicopters and gyros can kill you dead without specific class and category training. (Type-specific is better if you can). There are many old timers who followed the Bensen method. The problem with that is that while the graduated self-instruction method in his manual seems to work if painstakingly followed, most pilot-wannabees haven't the patience and self-discipline to follow it. A Bensen B8M of course had far less energy than the gyros of today -- with its wooden blades and optimistically-rated 72 HP Mac (more like 40 HP!) it could just barely kill you (although NTSB records from the period of peak Bensen popularity shows that it did, frequently). I have only ever flown Near CLT gyros, but have learned much from those who learned on machines like yours and who find the current generation of stable gyros to be superior in every wa In the end the ASTM subcommittee working on gyro consensus standards did not require any particular way of meeting the stability standard, but did set a stability standard and required it to be demonstrated in flight test. I do not believe an unmodified HTL gyro can pass that test. -- cheers -=K=- Rule #1: Don't hit anything big. |
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On 2005-04-26 11:33:46 -0400, "Stuart & Kathryn Fields" said:
extended line perpindicular to the prop and that line comes thru Greg higher than his chest, I'm not going to give you vertical c.g. to the 1 or 2 " That was Peter's number, but I think Greg has never claimed that it is CLT, but that it's reasonable close to CLT, and moreover, it is stable. It had a very good record worldwide, although I don't know what the results of the investigation of the fatal in Italy in, I think, 2003(?) have been. I do agree that CLT will make a safer ship. I don't agree with all of the emotional shouting that the non CLT ships were unstable and dangerous. Too many people are still successfully flying them. Reminds me of the famous quote about the BD-5 kitplane: "everyone who lived loved it!" BTW have you ever looked at the accident rate for CFI(G)? I've personally seen some of the dumbest flying comitted by CFIs. True. And ATPs. Two CFIs in one plane can be a hazardous condition, too. The thing is that there are three parts of learning, the motor skills stuff, the book/regulations stuff, and ... judgment. Judgment is very very hard to teach. A very good charter outfit just had a jet mishap in Texas with two 19,000 hour pilots on board. There is an excellent analysis of the accident in Business and Commercial Aviation this month. Something was bugging them about the way they had the modes set up on the display on the airplane, but they couldn't put their finger on it. A good procedure for that might be, go missed, go to hold, sort out the switchology and come back. But these guys had 19,000 hours of always coming through OK and it didn't seem like that big of a problem. I see the same thing in skydiving. Look at the accidents in Parachutist and you will see not so many novices as 5,000 jump D-licence pros who blew a judgment call once. I recently flew a 300# single seat helicopter owned by a man who self taught in the same helo. He could have gotten dual in a R-22, Bell 47, Schweitzer 300, or even a Brantly. Very little of the muscle memory derived from any of these ships would translate to his tiny ship. The experience of flying a lot of different helos probably would have helped. I think that negative transfer from a lifetime of flying Bells was as big a contribution to the demise of Allen Barklage as the exhaustively-discussed engine-out characteristics of the Mini-500. A personal friend got his ticket in a Bell 47 and had he tried to then solo his Safari, his checkout pilot said he would have crashed. My point is that you need to have a different experience baseline to be a test pilot in whatever than you do to fly a machine. The insurers have grabbed a hold of type-specific training and are worrying it like a dog with a bone. If I have a new guy come in with 1,000 twin hours, the insurers will not cover him as PIC in a Duchess (a simple twin trainer) until he has 10 hours dual in type. With an airplane, it's more learning the systems than getting a feel for the handling -- IMHO, that comes very quickly and an average twin pilot can master the handling of the Duchess in all flight regimes in an hour and spend the rest of the time on switchology. With a rotorcraft, you have both to deal with. You can't neglect the systems, but there is a much wider variation in what is considered normal handling and control feel. This is especially true in experimental aircraft, which are not required to meet any particular certification standard. . Similar problems were encountered in training in an RAF then solo your ultralite gyro. Well, yeah, that would be like doing an airplane PPL in a Cessna 206 with 1000 pounds of freight and then expecting a single-seat experimental to handle similarly. I don't have much time in a two seat gyro, but I did get the controls on the Sparrowhawk prototype and it didn't fly anything like my Benson. Had I gotten dual in that ship and then tried to fly my Benson I would have been unlearning a bunch of learned Sparrowhawk responses. What about some of the other twin trainers, like the Parsons and the old SnoBird? Or the Air Command? I haven't flown any of the two seat rails, just the sleds (SH and RAF). -- cheers -=K=- Rule #1: Don't hit anything big. |
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Kevin O'Brien wrote:
The experience of flying a lot of different helos probably would have helped. I think that negative transfer from a lifetime of flying Bells was as big a contribution to the demise of Allen Barklage as the exhaustively-discussed engine-out characteristics of the Mini-500. I don't care about the rest of your discussion here, so no comment. But, you got it wrong about Allen Barklage an his accident in his Mini-500. The Mini-500 has excellent engine-out characteristics, as demonstrated at almost every major air show. If properly set up by the builder, it could autorotate and land safely as low as 40 mph. Allen had great experience in his Mini-500 and was an expert at demonstrating autorotations. Where would lack of transition time from one helicopter to another have anything to do about Allan's accident, in the way you just tried to convey here? None whatsoever. Allen took off in his Mini-500 after it had an engine seizure due to improper jetting a flight before. He didn't bother to inspect the engine for seizure damage, and just flew it away as if nothing wrong had happened. Worse yet, he hugs the ground during his flight, and flies over a power line complex without gaining altitude. The engine finally failed over the lines, and he tried to milk the rotor rpm for more than any helicopter could have offered, and nosed into the ground after stalling the blades. Simple as that. It had nothing to do with transition time from one helicopter to another. It had already been determined that there is probably no single engine helicopter built that could have lost it's engine at that time and auturotated that distance at such a low altitude and landed safely. |
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On 2005-06-07 13:43:59 -0400, Dennis Fetters
said: Kevin O'Brien wrote: The experience of flying a lot of different helos probably would have helped. I think that negative transfer from a lifetime of flying Bells was as big a contribution to the demise of Allen Barklage as the exhaustively-discussed engine-out characteristics of the Mini-500. I don't care about the rest of your discussion here, so no comment. But, you got it wrong about Allen Barklage an his accident in his Mini-500. The Mini-500 has excellent engine-out characteristics, as demonstrated at almost every major air show. I recall one of them pranging at Sun n Fun, I think it was. A yellow one? Indeed, it might have been your demonstrator? Engine seize led to a hard landing and rolloever, IIRC, but I will look it up and get my facts straight if you want to argue about it. If properly set up by the builder, it could autorotate and land safely as low as 40 mph. What about the nose tuck? I have Rick Stitt's answer to that, and I wonder what yours is. Allen had great experience in his Mini-500 and was an expert at demonstrating autorotations. I'm aware of Allen's Mini-500 experience. He was probably the second or third highest time pilot in type at the time of his death, wasn't he? There was another fellow who had some 800 hours at the time, IIRC. Where would lack of transition time from one helicopter to another have anything to do about Allan's accident, in the way you just tried to convey here? None whatsoever. I'm not suggesting that it was transition "time" but negative transfer of skill, of experience, and of "muscle memory" under pressure, to use the latest fad term. Allen had done at least five for-real autos in the helicopters he was most familiar with, Bells. The Bell teetering rotor system has, as you well know, some similarities with the Mini and some rather pronounced differences. The biggest difference being (IMHO) rotor inertia. A standard drill at Army flight school is (or was in Allen's day, at least) to set the machine down, pick it up, pedal turn it 180 degrees, and set it down again. You wouldn't pull that off with a low-inertia design like the Mini -- or the R-22 for that matter. But you can do it with a Bell 47, UH-1, or 206/OH-58. Having had for-real autos in these machines, a pilot has a "feel" for what he can do. Like stretch a "glide" over some wires. Except you're not in the Bell, you definitely can't. I think negative transfer also contributed to some of the Robbie mishaps that led to the SFAR on training in the R-22. (FWIW, F.R. now says that if he knew his helicopter would have become the most popular trainer, he'd have designed it completely differently. He intended it to be a light, responsive machine for the experienced pilot seeking a sport or transport helicopter. He built the machine he wanted to fly himself). In a related matter, of fitness for purpose, I note that RHCI's very effective ads stressed all the cool things you could do and places you could go in a Mini-500. They imply it was easy as a bicycle and safe as mother's milk -- neither of which is true, you'll admit, of any helicopter. Allen took off in his Mini-500 after it had an engine seizure due to improper jetting a flight before. He didn't bother to inspect the engine for seizure damage, and just flew it away as if nothing wrong had happened. NTSB does not mention any prior seizure, or anything to do with carburettor jets. They do say: "A loss of engine power due to cold seizure of the power-takeoff cylinder." They retained the engine for examination after releasing most of the wreckage. https://www.ntsb.gov/ntsb/brief.asp?...11X11011&key=1 Worse yet, he hugs the ground during his flight, and flies over a power line complex without gaining altitude. Witness: "It was approximately 200 feet above the ground." Source: https://www.ntsb.gov/ntsb/brief2.asp...FA353& akey=1 The The engine finally failed over the lines, and he tried to milk the rotor rpm for more than any helicopter could have offered, and nosed into the ground after stalling the blades. The witness also noted that "The helicopter did not do a nose tuck," which indicates some familiarity with the type, if he was expecting that. Simple as that. It had nothing to do with transition time from one helicopter to another. It had already been determined that there is probably no single engine helicopter built that could have lost it's engine at that time and auturotated that distance at such a low altitude and landed safely. "It had already been determined" -- the passive voice is a bit evasive sounding here? Who determined that no single engine could lose its engine at 200 ft. and climbing (Witness: ""He was level and climbing, going away from me when all of a sudden, the sound (engine sound) went quiet, followed by a pop." - same NTSB narrative) and autorotated safely? I'm curious as to why your narrative is at such wide variance with NTSB's. They don't list RHCI as a party to the investigation, either. Buit I don't believe RHCI folded until one or two big shows after Allen's demise. Sorry for the belated reply, Dennis, and all. I don't check the newsgroups very often these days. -- cheers -=K=- Rule #1: Don't hit anything big. |
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Kevin O'Brien wrote:
On 2005-06-07 13:43:59 -0400, Dennis Fetters said: I'm curious as to why your narrative is at such wide variance with NTSB's. They don't list RHCI as a party to the investigation, either. RHCI don't need outside help to investigate accidents! Dennis "planeman" Fetters plays many roles, see the link below. Sorry for the belated reply, Dennis, and all. I don't check the newsgroups very often these days. You might have missed this gem: http://tinyurl.com/9m52c |
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10ft. of Decorative Chain wrote:
Kevin O'Brien wrote: On 2005-06-07 13:43:59 -0400, Dennis Fetters said: I'm curious as to why your narrative is at such wide variance with NTSB's. They don't list RHCI as a party to the investigation, either. RHCI don't need outside help to investigate accidents! Dennis "planeman" Fetters plays many roles, see the link below. Sorry for the belated reply, Dennis, and all. I don't check the newsgroups very often these days. You might have missed this gem: http://tinyurl.com/9m52c Yes, I wrote everything in every post that has my name on it in the link you give above. However, I did not write anything that has someone else's name to it. I write for myself, and hide behind no false names, as you do. Dennis Fetters |
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Kevin O'Brien wrote:
On 2005-06-07 13:43:59 -0400, Dennis Fetters said: Kevin O'Brien wrote: The experience of flying a lot of different helos probably would have helped. I think that negative transfer from a lifetime of flying Bells was as big a contribution to the demise of Allen Barklage as the exhaustively-discussed engine-out characteristics of the Mini-500. I don't care about the rest of your discussion here, so no comment. But, you got it wrong about Allen Barklage an his accident in his Mini-500. The Mini-500 has excellent engine-out characteristics, as demonstrated at almost every major air show. I recall one of them pranging at Sun n Fun, I think it was. A yellow one? Indeed, it might have been your demonstrator? Engine seize led to a hard landing and rolloever, IIRC, but I will look it up and get my facts straight if you want to argue about it. Dear Mr. O'Brien, I'm at a loss as to your counter-answer to my answering the statement you made about Allen's accident or it's relevance, and although I have published this here before, here is the correct information again. It was not Sun n Fun, it was Oshkosh. It was not a yellow one, but a red factory demonstrator. As for the cause of the accident, here is what the RHCI chief pilot published: ""As published in the September 1995 “Reaching the Customer” newsletter, the following report was written by Brian Thomas (RHCI’s Test Pilot): Many of you have been asking questions about the autorotation capabilities and crashworthiness of the Mini-500. Well, I will answer some of those questions, but this time with an actual experience... Oshkosh was less than a week away, the composite department was still in the learning stage and needed much supervision, and the assembly manual was a priority. Our minds were divided onto these other projects while we were working on preparing the aircraft for the show. As a result of this, we made three mistakes which caused this whole incident. First, we installed a new rotor/engine tachometer in the aircraft just before the fly-in. We thought the gauge was calibrated correctly. Also, we were using a new EGT gauge that was supposed to be self-compensating for temperature. The week before Oshkosh, the temperature at the factory was 95 to 100 degrees F. with 95% humidity. After making these changes, the aircraft experienced a loss in performance. Our EGT temperatures were only running about 900 to 1000 degrees F. We attributed this loss of performance to the high temperature and humidity. Using the EGT gauge as a guide, we leaned the mixture by installing much smaller main jets and lowering the needles. This brought the temperature up to 1100 and 1200 degrees F., but with no significant increase in performance. Through testing, we then learned that the rotor/engine tachometer was calibrated too low. After re-calibration, our performance returned. EGT’s were still reading normally and were left as changed. I immediately conducted a short test flight and everything seemed to be working well. Second, we installed wear shoes on the bottom of the skids to prevent excessive wear on concrete and rocky surfaces. Our intentions were to make this an option later. These shoes consisted of eight pieces of steel, four per skid, approximately five inches long, riveted with six rivets each, evenly spaced along the skids. Third, we did not test the skid shoes on grass or dirt to see if they would change the run-on landing performance. Now for what happened at Oshkosh. It was the first flight on the first day of the show. I started the aircraft and hovered around the grass runway for a few minutes and the aircraft was operating normally. I then departed and entered the traffic pattern. On my first trip around the pattern, the aircraft was performing perfectly. I was keeping an eye on the EGT gauge to make sure that the temperatures were still good, since it was cooler at Oshkosh than at the factory. The temperature was still 1100 and 1200 degrees F. On my second trip around the pattern, the engine suddenly stopped. The EGT gauge that we installed was not as accurate as we thought and the engine hot seized. At the time the engine quit, I was at 300 feet AGL with an airspeed of 70 MPH. I entered autorotation and steered for a nearby clover field. The autorotation was uneventful, as was the flair and touchdown. As I have previously said, the Mini-500 is one of the best autorotating helicopters I have ever flown. The problems began during the ground slide. Immediately upon touchdown, the skid shoes caught in the clover and soft dirt so hard that one shoe was pulled off the skid! The left skid caught and jerked so hard that the legs buckled. The legs did not buckle because they are not strong enough. They buckled from the enormous force of trying to stop 730 lbs. of aircraft so quickly. The skid shoes were the cause, not the legs. When the left skid buckled, the aircraft started to go onto its left side. As a result, one rotor blade contacted the tail boom. Part of the reason that the skid shoes caught so hard is that the normal procedure for the Mini-500 is to lower the collective all the way down after touchdown from an auto. On most helicopters with skid shoes, the procedure is to hold the collective up until the helicopter comes to a stop to prevent the shoes from digging in too badly. I am very familiar with this procedure, but failed to relate it to the Mini-500."" Completely our fault. If properly set up by the builder, it could autorotate and land safely as low as 40 mph. What about the nose tuck? I have Rick Stitt's answer to that, and I wonder what yours is. Rich Stitt is a back stabbing thieving parasitic traitor that bits the hands that and feed him. The is a convicted child beating criminal that takes advantage of old single ladies emotions and then drains their bank accounts before he moves on to the next one. If you want to believe anything he says, go for it. As you can read what I said above: "If properly set up by the builder, it could autorotate and land safely as low as 40 mph." I have already answered this here before, but, there were a few customers that listened to the advice of another famous customer and set their blade tips at negative 1.5 degrees instead of the 0.5 negative the factory stated. This would lead to a nose tuck when dumping the collective, and in one case caused the main blades to droop so low as to cut a grove out of the customers tail boom. If following instructions, as you should, by setting the blades to factory specifications and leading with cyclic before collective, just like in an R-22, there was no significant nose drop. After further development, RHCI came up with a trim tab and a stall strip that took away all nose drop when you dumped the collective. Just read the KitPlanes pilot evaluation report they published. Allen had great experience in his Mini-500 and was an expert at demonstrating autorotations. I'm aware of Allen's Mini-500 experience. He was probably the second or third highest time pilot in type at the time of his death, wasn't he? Good for you for being aware, then what's your point because I'm missing it? There was another fellow who had some 800 hours at the time, IIRC. He didn't have nearly 800 hours, but here is what you are eluding too: "The pilot had installed his Mini-500 “Power Enhancement Package” (PEP), and against RHCI’s severe warnings, chose not to use the provided jet package containing a 2.76 needle jet. Instead he installed a 2.78 needle jet which meant that he needed a 155 main jet to achieve the proper EGT in hover. RHCI informed the pilot that the engine would seize with this small main jet, when at high-power settings it could not supply sufficient fuel to the engine, causing it to heat and seize. The main jet should have been a 165 or 170. Also, he had erroneously set the needle in the third position on the cylinder that seized; the other was correct in the fourth position. He was flying over a forest when the engine seized, and autorotated into a 50-foot tall tree. The impact broke the mast and the aircraft fell and landed upside down on the ground." Pilot error. Where would lack of transition time from one helicopter to another have anything to do about Allan's accident, in the way you just tried to convey here? None whatsoever. I'm not suggesting that it was transition "time" but negative transfer of skill, of experience, and of "muscle memory" under pressure, to use the latest fad term. Allen had done at least five for-real autos in the helicopters he was most familiar with, Bells. OK, let's do it again: Where would lack of "muscle memory" from one helicopter to another have anything to do about Allan's accident, in the way you just tried to convey here? None whatsoever. The Bell teetering rotor system has, as you well know, some similarities with the Mini and some rather pronounced differences. The biggest difference being (IMHO) rotor inertia. A standard drill at Army flight school is (or was in Allen's day, at least) to set the machine down, pick it up, pedal turn it 180 degrees, and set it down again. You wouldn't pull that off with a low-inertia design like the Mini -- or the R-22 for that matter. But you can do it with a Bell 47, UH-1, or 206/OH-58. Having had for-real autos in these machines, a pilot has a "feel" for what he can do. Like stretch a "glide" over some wires. Except you're not in the Bell, you definitely can't. I didn't write the above statement. But you are correct. I think negative transfer also contributed to some of the Robbie mishaps that led to the SFAR on training in the R-22. No comment, let Frank answer that. I love to fly the R-22 and R-44. In my opinion they are fine designs. (FWIW, F.R. now says that if he knew his helicopter would have become the most popular trainer, he'd have designed it completely differently. He intended it to be a light, responsive machine for the experienced pilot seeking a sport or transport helicopter. He built the machine he wanted to fly himself). Let Frank answer that, I don't claim to know anything that was in his mind at the time. What ever it was, was correct, because I think he is the most successful helicopter producer in the world. In a related matter, of fitness for purpose, I note that RHCI's very effective ads stressed all the cool things you could do and places you could go in a Mini-500. They imply it was easy as a bicycle and safe as mother's milk -- neither of which is true, you'll admit, of any helicopter. You are wrong. We did say all the cool things you could do, because you can. And we did them, and some still do. But, you will never see in anything published by RHCI where we said flying a helicopter is safe, because flying helicopters is not safe, and in fact full of risks. Our warnings alone made some people not buy. At the air shows we always had an assembly manual on the table, and the first few pages were dedicated to the risks involved in helicopter flight, with a skull and cross bones and 8 different warnings, so on. The Mini-500 is easy to fly, and many stated it was the easiest and most stable helicopter they had ever flown. But, we never implied anyone could fly it without training. As a matter of fact, we forced our customers to prove they had training before we would ship them the complete kit. No other manufacturer I know of did that when we were in business. Your comment above was false, out of place and even malicious. Allen took off in his Mini-500 after it had an engine seizure due to improper jetting a flight before. He didn't bother to inspect the engine for seizure damage, and just flew it away as if nothing wrong had happened. NTSB does not mention any prior seizure, or anything to do with carburettor jets. They do say: "A loss of engine power due to cold seizure of the power-takeoff cylinder." They retained the engine for examination after releasing most of the wreckage. https://www.ntsb.gov/ntsb/brief.asp?...11X11011&key=1 That's right, nor do they probably know anything about Rotax engines in helicopters and the differences involved, as they demonstrated to me on more than one occasion. Nor did they bother to say just a short time before he crashed his Mini-500 by climbing out of it with the blades still turning at full RPM, so he could point to some people where to land, and his Mini-500 took off!! And he didn't report it, and even though his FAA buddies found out they never did anything about it. No wonder it was not mentioned in the accident report later. Let's look at this for a moment: The witness was on the airport, and the Mini-500 was 150 or less above him, and still over the airport. The power lines are about 1000 feet away from the witness. Already 150 feet high over the witness, Allen only climbed 50 more feet over a 1000 foot distance to clear a power line complex. It shows that he had no concern about climbing high enough, as we are all trained to do to clear an obstacle in case of engine failure. Pilot error. It was 83 degrees F. The witness, standing on the opposite side on a large hanger, heard the Mini-500 running behind the hanger complex, then he watched it fly from around the hanger making a wide and level turn towards him climbing to 150 feet or so, then flying away almost 900 feet before the engine failed. The point is, between the mandatory warm-up time, hover time, flying from around the hanger time, wide level turn time, flying toward the witness while climbing to 150 feet time, and flying 900 feet away while climbing an additional 50 feet time, the Mini-500 had plenty of warm up time not to have cold seizure. Cold seizures in a Mini-500 have only happened when the pilot starts the engine cold, and immediately lifts into a climbing departure, and then the engine will seize within 100 feet or so and not turn until later after the piston cooled enough to allow it to do so. It's Pilot error. Look at the report: "The top of the piston showed foreign material impact strikes in the squish-band area. Small particles of foreign metallic material were found embedded in the piston head. Impact marks were found in the top dome of the power-takeoff cylinder. The two power-takeoff cylinder spark plugs' electrodes showed no gap. The bottom of both electrodes showed impact marks." "the sound (engine sound) went quiet, followed by a pop". Again, dose that sound like an engine that just cold seized, when the engine can still turn to allow a "pop" from a misfire. The engine quit because the spark plug gaps were closed from the previous contamination pounding them shut. Dose that sound like something was COLD? Not at all. That was an engine failure due to disintegration of parts. Just like if you seize an engine, and then run it again without fixing it by removing the damaged parts and metal, and just like what I said when Allen himself called me to tell me he seized his engine and he didn't bother to fix it right before the crash. The engine got hot, and darn hot at that. Nothing cold about it. In fact, a cold seizure shows only scuffing from sudden expansion of the piston squeezing in the cylinder, because the cylinder was not given time to expand. You will not find the metal as what was found in Allen's engine that was large enough to de-gap the plugs. Worse yet, he hugs the ground during his flight, and flies over a power line complex without gaining altitude. Witness: "It was approximately 200 feet above the ground." Source: https://www.ntsb.gov/ntsb/brief2.asp...FA353& akey=1 Just like I said. 200 feet high and 1000 feet away from the airport property boundries, and only climed 50 more feet in that distance from the airport. Pilot error. The engine finally failed over the lines, and he tried to milk the rotor rpm for more than any helicopter could have offered, and nosed into the ground after stalling the blades. The witness also noted that "The helicopter did not do a nose tuck," which indicates some familiarity with the type, if he was expecting that. I didn't say it did a "nose tuck". I said it nosed into ground after stalling the blades, meaning the nose pointing the direction of travel. As the report indicated, he still had some forward speed, just no lift and little RPM, as the blade damage described in the report would indicate. Simple as that. It had nothing to do with transition time from one helicopter to another. It had already been determined that there is probably no single engine helicopter built that could have lost it's engine at that time and auturotated that distance at such a low altitude and landed safely. "It had already been determined" -- the passive voice is a bit evasive sounding here? Who determined that no single engine could lose its engine at 200 ft. and climbing (Witness: ""He was level and climbing, going away from me when all of a sudden, the sound (engine sound) went quiet, followed by a pop." - same NTSB narrative) and autorotated safely? My conversation with the FAA and other expirianced helicopter people in the area. They said it. I'm curious as to why your narrative is at such wide variance with NTSB's. They don't list RHCI as a party to the investigation, either. Buit I don't believe RHCI folded until one or two big shows after Allen's demise. My above answers should also answer this question. The only thing I'm disagreeing with in the FAA report is the cold seizure. They are in error to report that, because that was not the cause of the engine failure, as I comprehensively explained above. Sorry for the belated reply, Dennis, and all. I don't check the newsgroups very often these days. Welcome back. Sincerely, Dennis Fetters |
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Kevin: I think the heavy really makes a difference. Before I had any helo
training, I got the opportunity to fly a UH-1N. I was able to actually hover the beast with full controls and make pedal turns the first try. I figured that I must be one of those "naturals" and charged off to an R-22. In about 4 seconds I had my tail between my legs wondering what had happened. I've had a ride in a tandem gyro trainer, but it also felt much heavier and ponderous than my Benson. I agree that a lot of experience in different ships will really help the test pilot. But the beginner doesn't have that luxury...I certainly agree that instruction pays off even if you have to just have ground instruction with an instructor watching your taxiing and first lift offs. With radio communication it is possible to gently enter the flight mode if done dang carefully. "Kevin O'Brien" kevin@org-header-is-my-domain-name wrote in message news:2005060513075116807%kevin@orgheaderismydomain name... On 2005-04-26 11:33:46 -0400, "Stuart & Kathryn Fields" said: extended line perpindicular to the prop and that line comes thru Greg higher than his chest, I'm not going to give you vertical c.g. to the 1 or 2 " That was Peter's number, but I think Greg has never claimed that it is CLT, but that it's reasonable close to CLT, and moreover, it is stable. It had a very good record worldwide, although I don't know what the results of the investigation of the fatal in Italy in, I think, 2003(?) have been. I do agree that CLT will make a safer ship. I don't agree with all of the emotional shouting that the non CLT ships were unstable and dangerous. Too many people are still successfully flying them. Reminds me of the famous quote about the BD-5 kitplane: "everyone who lived loved it!" BTW have you ever looked at the accident rate for CFI(G)? I've personally seen some of the dumbest flying comitted by CFIs. True. And ATPs. Two CFIs in one plane can be a hazardous condition, too. The thing is that there are three parts of learning, the motor skills stuff, the book/regulations stuff, and ... judgment. Judgment is very very hard to teach. A very good charter outfit just had a jet mishap in Texas with two 19,000 hour pilots on board. There is an excellent analysis of the accident in Business and Commercial Aviation this month. Something was bugging them about the way they had the modes set up on the display on the airplane, but they couldn't put their finger on it. A good procedure for that might be, go missed, go to hold, sort out the switchology and come back. But these guys had 19,000 hours of always coming through OK and it didn't seem like that big of a problem. I see the same thing in skydiving. Look at the accidents in Parachutist and you will see not so many novices as 5,000 jump D-licence pros who blew a judgment call once. I recently flew a 300# single seat helicopter owned by a man who self taught in the same helo. He could have gotten dual in a R-22, Bell 47, Schweitzer 300, or even a Brantly. Very little of the muscle memory derived from any of these ships would translate to his tiny ship. The experience of flying a lot of different helos probably would have helped. I think that negative transfer from a lifetime of flying Bells was as big a contribution to the demise of Allen Barklage as the exhaustively-discussed engine-out characteristics of the Mini-500. A personal friend got his ticket in a Bell 47 and had he tried to then solo his Safari, his checkout pilot said he would have crashed. My point is that you need to have a different experience baseline to be a test pilot in whatever than you do to fly a machine. The insurers have grabbed a hold of type-specific training and are worrying it like a dog with a bone. If I have a new guy come in with 1,000 twin hours, the insurers will not cover him as PIC in a Duchess (a simple twin trainer) until he has 10 hours dual in type. With an airplane, it's more learning the systems than getting a feel for the handling -- IMHO, that comes very quickly and an average twin pilot can master the handling of the Duchess in all flight regimes in an hour and spend the rest of the time on switchology. With a rotorcraft, you have both to deal with. You can't neglect the systems, but there is a much wider variation in what is considered normal handling and control feel. This is especially true in experimental aircraft, which are not required to meet any particular certification standard. . Similar problems were encountered in training in an RAF then solo your ultralite gyro. Well, yeah, that would be like doing an airplane PPL in a Cessna 206 with 1000 pounds of freight and then expecting a single-seat experimental to handle similarly. I don't have much time in a two seat gyro, but I did get the controls on the Sparrowhawk prototype and it didn't fly anything like my Benson. Had I gotten dual in that ship and then tried to fly my Benson I would have been unlearning a bunch of learned Sparrowhawk responses. What about some of the other twin trainers, like the Parsons and the old SnoBird? Or the Air Command? I haven't flown any of the two seat rails, just the sleds (SH and RAF). -- cheers -=K=- Rule #1: Don't hit anything big. |
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