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#111
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On Tue, 28 Oct 2003 15:43:58 -0600, Barnyard BOb --
wrote: The "wannabees, fruits, flakes and fringe folks" would include such poseurs as Steve Wittman, Roger Mellema, Ray Geschwender, Bernie Pietenpol, Ray Ward, Jerry Schweitzer and the Reverend Ron Van der Camp. Some of the afore mentioned people designed auto conversions, some designed entire airplanes, but all of the flew behind auto conversions at one time or another. You might recognize a couple of the names. Corky (rolling my eyes) Scott ===================================== Enough of your brand of distortion, Corky. Cease twisting my words to your agenda. Pardon? I twisted your words? See below. I do not consider Steve Wittman, Roger Mellema, Ray Geschwender, Bernie Pietenpol, Ray Ward, Jerry Schweitzer and the Reverend Ron Van der Camp in YOUR class of activity. FAR from it, sir. Neither do I. SO...quit flattering yourself right now !!!!! Here are the words you typed, presumably you meant them: "The wannabees, fruits, flakes and fringe folks deserve a shot at the microphone.... but I'll not give them a free pass, even if it is pointless." What I pointed out is that better men that me (as you said and to which I agree) have chosen to fly behind auto engine conversions, none of whom were flakes or wannabees. What I'm doing is attempting to follow in their footsteps. I take full responsibility for the path I'm following. I'm in the process of fabricating an engine test stand as you read this. I fully intend to run the engine for many hours (with a prop installed) prior to installing it in the engine compartment for good. Corky Scott |
#112
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That's a valid point. Let's say we have a couple of early versions break
crankshafts. The cranks are changed, or maybe the balance is changed and all appears to be well. The article is submitted with test results for certification. It is certified. A couple dozen are placed into service. Crankshafts start breaking. Think the FAA will have any problems getting those pre-presentation test results? Not if that manufacturer ever wants to sell anything as certified again, they won't. Certified Manufacturers are that way and charge what they do for a reason. That reason IS the certification. If it was easy to be certified, their SeaBee conversion would be certified, but it's not an easy thing to do or maintain. John Stricker "Kevin Horton" wrote in message news On Tue, 28 Oct 2003 20:02:59 -0600, John Stricker wrote: Dave, Can we? I don't know if FOI covers that, but the FAA certification division sure can. And they have the failure reports on file. That's the point, though. These conversions AREN'T certified. In effect WE are the certifying entity and as such the responsibility falls on us and we can't make that decision with glossed over reports of "trouble-free" service. John Stricker If the failures happen during development, and they make design changes to address the failure before they present the engine to the FAA for type certification, then the FAA may very well not have anything on file. The FAA makes a very big point about not getting out the microscope until they are presented a test article that conforms to the type design. The definition of the type design evolves during the development process as problems are found and fixed. "Dave Hyde" wrote in message ... John Stricker wrote: If I'm going to by into something like an auto conversion, I want to know how it's failed in the past JUST LIKE I KNOW HOW THE LYCOMINGS AND CONTINENTALS HAVE FAILED BECAUSE IT'S PUBLIC RECORD FOR THE LAST 50 YEARS. I hope I didn't scare you with my shouting. 8-) Not me, anyway, but I have an honest question: Do major GA engine manufacturers make data on failures *in development* available to the public? Can we see test-to-failure data on the new engines Lycoming, Superior, Mattituck, etc. are putting out for homebuilts? Where? Seems to me what an auto conversion needs is a 'sugar daddy' to put up big $$$ to fund develompent and testing testing testing. I'm not holding my breath. Dave 'enquiring mind' Hyde -- Kevin Horton RV-8 (finishing kit) Ottawa, Canada http://go.phpwebhosting.com/~khorton/rv8/ e-mail: khorton02(_at_)rogers(_dot_)com |
#113
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Del
A true story that probably could be included under shock cooling. In the P-51/Merlin (liquid cooled) we used to pitch off the deck (50 --100 feet -- 250 mph +/-) into the landing pattern. As we pitched up we pulled the throttle to idle and the Merlin would go 'poppety pop' out the short stacks all the way around the pattern (wonderful sound to listen to G) Some one got to investigating warped exhaust valves and found that the valve timing was such that the engine sucked a lot of outside air (cold) into the cylinder thru the exhaust valves at idle and with the valves being 'hot' from cruise power, the cold air being sucked by warped them. Solution. They let us only pull the throttle back to 10 --12 inches on pitch. If you went 'poppety pop' in pattaern the Ops Officer would hear and chew A**. As we flew around the pattern at the low power setting the valves cooled and on final we went to idle for the touchdown. Voila, no more warped valves. So, Liquid cooling of an aircraft engine didn't eliminate all of the 'shock' cooling problems. Big John On 29 Oct 2003 03:22:42 GMT, Del Rawlins wrote: On 28 Oct 2003 05:51 PM, Dave Hyde posted the following: Del Rawlins wrote: ----clip---- Not quite on the same level. Where can I get a liquid cooled Lycoming for my Bearhawk? It's a little bit of extra weight to lug around, but worth it to me. Others don't seem as bothered by the need to baby their engine on a descent to avoid shock cooling, or the suicidal heating system used in most GA aircraft (where a slight undetected crack can lead to CO poisoning). ----clip---- |
#114
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Big John wrote:
Del A true story that probably could be included under shock cooling. In the P-51/Merlin (liquid cooled) we used to pitch off the deck (50 --100 feet -- 250 mph +/-) into the landing pattern. As we pitched up we pulled the throttle to idle and the Merlin would go 'poppety pop' out the short stacks all the way around the pattern (wonderful sound to listen to G) Some one got to investigating warped exhaust valves and found that the valve timing was such that the engine sucked a lot of outside air (cold) into the cylinder thru the exhaust valves at idle and with the valves being 'hot' from cruise power, the cold air being sucked by warped them. Solution. They let us only pull the throttle back to 10 --12 inches on pitch. If you went 'poppety pop' in pattaern the Ops Officer would hear and chew A**. As we flew around the pattern at the low power setting the valves cooled and on final we went to idle for the touchdown. Voila, no more warped valves. So, Liquid cooling of an aircraft engine didn't eliminate all of the 'shock' cooling problems. Big John On 29 Oct 2003 03:22:42 GMT, Del Rawlins wrote: On 28 Oct 2003 05:51 PM, Dave Hyde posted the following: Del Rawlins wrote: ----clip---- Not quite on the same level. Where can I get a liquid cooled Lycoming for my Bearhawk? It's a little bit of extra weight to lug around, but worth it to me. Others don't seem as bothered by the need to baby their engine on a descent to avoid shock cooling, or the suicidal heating system used in most GA aircraft (where a slight undetected crack can lead to CO poisoning). ----clip---- John The mufflers on this conversion would probably go a long way to eliminate the problem of valve warping as compared to the short open stacks on the mustang. Jim Stockton |
#115
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Jim
I only posted a bit of triva. Am sure no one on thread had ever heard of the problem. Your right, long stacks or a muffler would prevent the valve warping, like on the Merlin, today either with an air or liquid cooled engine.??? Big John On Wed, 29 Oct 2003 14:44:44 -0600, Jim Stockton wrote: Big John wrote: Del A true story that probably could be included under shock cooling. In the P-51/Merlin (liquid cooled) we used to pitch off the deck (50 --100 feet -- 250 mph +/-) into the landing pattern. As we pitched up we pulled the throttle to idle and the Merlin would go 'poppety pop' out the short stacks all the way around the pattern (wonderful sound to listen to G) Some one got to investigating warped exhaust valves and found that the valve timing was such that the engine sucked a lot of outside air (cold) into the cylinder thru the exhaust valves at idle and with the valves being 'hot' from cruise power, the cold air being sucked by warped them. Solution. They let us only pull the throttle back to 10 --12 inches on pitch. If you went 'poppety pop' in pattaern the Ops Officer would hear and chew A**. As we flew around the pattern at the low power setting the valves cooled and on final we went to idle for the touchdown. Voila, no more warped valves. So, Liquid cooling of an aircraft engine didn't eliminate all of the 'shock' cooling problems. Big John On 29 Oct 2003 03:22:42 GMT, Del Rawlins wrote: On 28 Oct 2003 05:51 PM, Dave Hyde posted the following: Del Rawlins wrote: ----clip---- Not quite on the same level. Where can I get a liquid cooled Lycoming for my Bearhawk? It's a little bit of extra weight to lug around, but worth it to me. Others don't seem as bothered by the need to baby their engine on a descent to avoid shock cooling, or the suicidal heating system used in most GA aircraft (where a slight undetected crack can lead to CO poisoning). ----clip---- John The mufflers on this conversion would probably go a long way to eliminate the problem of valve warping as compared to the short open stacks on the mustang. Jim Stockton |
#116
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Some years ago a company was building Ford engines for installation in
homebuilts. They did a couple of experiments of running the engine, with a prop, without coolant. On both occasions the broken-in engines ran for 30+ minutes. Both stopped due to expansion of the pistons in the bores. When the engines cooled the coolant systems were filled and the engines started. Both ran and turned the prop at the same rpm. But also both engine's head gaskets were shot and the metallurgy of both the heads and the pistons had changed to the point of all having to be relegated to the scrap pile. Crank and rod bearings were still in good condition. Bruce A. Frank Ron Wanttaja wrote: "Jerry Springer" wrote in message Better way? New design yes... auto engines no. Sorry I have not been flying quite as long as Barnyard, only about 40 years for me. BUT every auto engine conversion I know of has had a failure of some type. But look at the bright side: With this one, if the SeaBee engine fails, you get to shoot the dead-stick landing in air-conditioned comfort. :-) On Mon, 20 Oct 2003 20:22:17 -0700, "Bart D. Hull" wrote: I can buy the third issue. But what if it was a FADEC on a Cont or a LYC instead? They quit without juice as well. But Continental and Lycoming had to convince a *very* skeptical FAA about the reliability of the FADEC. They had to prove that the FADEC is at least as reliable as two magnetos. I remember an article, years ago, about what Porsche had to do to certify the PFM engine for the Mooney. They had to prove the two independent ignition systems *were* completely independent. I think they even had to apply a sudden dead short across one, just to prove the other one would keep running. I'm not being argumentative, but want more details so my auto-conversion will be more successful than a LYC or Cont install. A good goal, and worthy of discussion. With one exception, the failures I hear about have been fairly random, mostly related to the subsystems rather than the core engine. I think the lesson would be to strive for maximum redundancy. There *should* be two completely independent ignition systems. Two batteries, two electronics boxes, two sets of plug wires, two plugs per cylinder. The second should be solely a backup, connected to *nothing* in common with the primary system. If the primary system uses the distributor drive to time the ignition, the backup system should run off a hall effect sensor on the flywheel. Buy a drycell battery and run it directly to the backup ignition electronics...no connection to the primary bus. I say a drycell simply because of their ability to hold a charge a long time. Test the ignition momentarily during runup and slap a charger on the backup system every week or so. That way if your electrical system goes to hellandgone, you've got a completely independent backup. The drycell should be sized to give you at least a half-hour of flight time...I'm basing that on the required VFR fuel reserve. Probably your biggest worry, compared to a Lycosaur, is cooling. The air cooling of your classic aircraft engine is extremely reliable...if it cools properly when it's initially installed, there's very little that can happen to it to make it NOT cool. If the oil cooler quits working, the engine probably will last long enough to get you to a runway (other than if it spews oil everywhere, of course). You're not going to match that level of reliability; your airplane will have a water pump, water hoses, and radiator that the Lycosaur lacks and thus can't stop running if they quit. The lesson here is probably to use the best quality parts you can find (race-type hoses, etc.) and to oversize the system... if you develop a coolant leak in flight, it's nice if your plane has to lose five gallons of coolant before it starts to overheat rather than five quarts. Gauge the heck out of it, too...you want to be able to detect problems as early as possible. I'd try put together some sort of annunciator system rather than depend on the pilot's eyes to catch a fading gauge. I wonder what could be done along the lines of emergency cooling, like the emergency ignition? The AVweb article about flying the Hawker Hurricane makes me wonder about a spray-bar system for auto-engine conversions. Could you gain some flying time if you had a system that would spray the engine itself with water? And/Or some emergency cowl flaps that would open and expose the engine case directly to the slipstream? The PSRU is another single point failure item. I don't know what one could do to increase redundancy, but plenty of design margin would be a good start. Regular, in-depth inspections would be another...guy across from me just found a crack in one plate of his gyro's PSRU. Years ago, Kit Sondergren had an article in KITPLANES about terminating the A-65 engine on his Mustang. He decided it needed to get overhauled, so he tried a little experiment...he drained out all the oil and ran it on the ground. IIRC, that engine ran at moderate throttle for something like a half-hour before it really started to labor. I *like* that in an aircraft engine. Nothing for cooling but the slipstream, two independent ignition systems that generate their own power, and a engine that'll run for a fairly long while with no oil at all. Lycomings and Continentals have one thing in common with the dinosaurs: They leave mighty big shoes to fill. :-) I'm cautious about auto-engine conversions, but I wholly support those who want to experiment with them. I like your attitude about wanting more details to help improve your own work. Please continue to plug yourself into information sources to build the safest engine possible. Ron Wanttaja |
#117
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Some years ago a company was building Ford engines for installation in homebuilts. They did a couple of experiments of running the engine, with a prop, without coolant. On both occasions the broken-in engines ran for 30+ minutes. Both stopped due to expansion of the pistons in the bores. When the engines cooled the coolant systems were filled and the engines started. Both ran and turned the prop at the same rpm. But also both engine's head gaskets were shot and the metallurgy of both the heads and the pistons had changed to the point of all having to be relegated to the scrap pile. Crank and rod bearings were still in good condition. Bruce A. Frank ++++++++++++++++++++++++++++++++++++++++++ What RPM? What power level? Unless producing realistic in-flight power.... is there value in this exercise beyond PR? Barnyard BOb -- |
#118
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"Barnyard BOb --" wrote in message
... Some years ago a company was building Ford engines for installation in homebuilts. They did a couple of experiments of running the engine, with a prop, without coolant. On both occasions the broken-in engines ran for 30+ minutes. Both stopped due to expansion of the pistons in the bores. When the engines cooled the coolant systems were filled and the engines started. Both ran and turned the prop at the same rpm. But also both engine's head gaskets were shot and the metallurgy of both the heads and the pistons had changed to the point of all having to be relegated to the scrap pile. Crank and rod bearings were still in good condition. Bruce A. Frank ++++++++++++++++++++++++++++++++++++++++++ What RPM? What power level? Unless producing realistic in-flight power.... is there value in this exercise beyond PR? Barnyard BOb -- What PR? As I read it, if you're cooling system fails you basically have enough time to set it down then you're looking at a new engine. Eric |
#119
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On Thu, 30 Oct 2003 12:45:26 GMT, "Eric Miller"
wrote: "Barnyard BOb --" wrote in message .. . Some years ago a company was building Ford engines for installation in homebuilts. They did a couple of experiments of running the engine, with a prop, without coolant. On both occasions the broken-in engines ran for 30+ minutes. Both stopped due to expansion of the pistons in the bores. When the engines cooled the coolant systems were filled and the engines started. Both ran and turned the prop at the same rpm. But also both engine's head gaskets were shot and the metallurgy of both the heads and the pistons had changed to the point of all having to be relegated to the scrap pile. Crank and rod bearings were still in good condition. Bruce A. Frank ++++++++++++++++++++++++++++++++++++++++++ What RPM? What power level? Unless producing realistic in-flight power.... is there value in this exercise beyond PR? Barnyard BOb -- What PR? As I read it, if you're cooling system fails you basically have enough time to set it down then you're looking at a new engine. Eric So far, I've not read of any reported catastrophic coolant losses in the Ford powered airplanes. There have been instances (I've read of two in Bruce's newletter) in which the head gasket began leaking. This resulted in pressure readings that were abnormal, and the pilots in both instances noticed them. The airplanes were flown back to their home fields and the head gaskets were replaced. In one instance, the airplane was a fair distance from the field. Inflight coolant temperatures did not change much, it was the pressure when the engine was shut down that got the pilot's attention. When you think about it, where where might a catastrophic leak occur and how? Could a hose burst? A hole develop in the radiator? Those things normally don't just blow up and spew out everything, they leak very slowly at first, and a thorough preflight should include looking for signs of coolant leakage I'd think. When you put together a water cooled auto conversion, you use premium hoses and radiators, right? You don't install aged and hardened parts do you? Well I'm not going to anyway. Corky Scott |
#120
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Some years ago a company was building Ford engines for installation in homebuilts. They did a couple of experiments of running the engine, with a prop, without coolant. On both occasions the broken-in engines ran for 30+ minutes. Both stopped due to expansion of the pistons in the bores. When the engines cooled the coolant systems were filled and the engines started. Both ran and turned the prop at the same rpm. But also both engine's head gaskets were shot and the metallurgy of both the heads and the pistons had changed to the point of all having to be relegated to the scrap pile. Crank and rod bearings were still in good condition. Bruce A. Frank ++++++++++++++++++++++++++++++++++++++++++ What RPM? What power level? Unless producing realistic in-flight power.... is there value in this exercise beyond PR? Barnyard BOb -- What PR? As I read it, if you're cooling system fails you basically have enough time to set it down then you're looking at a new engine. Eric +++++++++++++++++++++++++++++++++++++++++ I sincerely and most humbly apologize. My generosity was aimed to cut these defunct folks some slack. However, I have no problem seeing it your way. g Barnyard BOb -- |
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