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OK William, since you climbed off the soap box and left it unattended, I guess I have a duty to climb back on and re-butt your rebuttal! When I'm done, I'll relinquish said soap box and you can climb back on. My comments:
In a message dated 10/24/2005 2:42:56 AM Eastern Daylight Time, WRB writes:
<<I understand exactly where you are coming from, but any black and white presentation ignores the gray of reality. To begin with, comparing a Piper Cherokee built in 1975 with an Ercoupe designed in 1939 is apples and oranges. Those 36 years are important in terms of how things were done.>>
I wasn't comparing a Piper Cherokee to an Ercoupe. I was making the point that if a part that is not up to the task at hand is put into a critical application, people can and do die. The type of airplane and when it was built have nothing to do with it. Not every pilot/owner out there (me included) is qualified to do a valid engineering analysis every time he decides to put a Case tractor fuel pump on a Continental engine, or put a Pep Boys muffler clamp on a Cherokee's exhaust system. The two scenarios are the same. In both cases a qualified engineer or designer specified a certain part for a specific application. Later, someone who was only interested in saving a dollar or a few hours decided that they knew more about the design, metallurgy, geometry, quality and service history of the subject part and decided that the tractor part or made-in-china auto part would work just as well. Or what happens more often, someone substituted the part without even realizing or thinking about the possible consequences of what they were doing. After all, it's just a clamp. It's just a fuel pump. It's just an oil hose. Apples to apples.
<<For the owner/pilot of 1939, Fred Weick used all the "tricks" to keep the cost down. I don't recall the specifics (I DO have the information in my files), but the fuel pump on production Ercoupes was a common off-the-shelf automotive design. Overhaul kits were available at the local Western Auto, etc. This was what the manufacturer specified and used in TC 718 production airframes.>>
<<For the owner/pilot of 1939, Fred Weick used all the "tricks" to keep the cost down. I don't recall the specifics (I DO have the information in my files), but the fuel pump on production Ercoupes was a common off-the-shelf automotive design. Overhaul kits were available at the local Western Auto, etc. This was what the manufacturer specified and used in TC 718 production airframes.>>
If the original designer decided that an automotive part was suitable for use on an airplane, then there isn't a thing in the world wrong with that. In fact *some* auto parts are of better quality than similar aircraft parts. What is wrong is sending an unsuspecting owner to the auto parts store today, in 2005, looking for "a fuel pump for a 39 Ford" and having him put it on an airplane that he's going to fly some innocent kid around in. If the "common off-the-shelf automotive design" fuel pump is OK to use on a C-90-16F engine for example, then what is the Pep-Boys part number that I should buy? Can Pep-Boys tell me the right part number for that engine? If not, then who can? Or should I just guess and get one that looks about right? Does Pep-Boys make sure that their Chinese supplier doesn't change the design or materials in the middle of a production run? Is there any accountability as to what kind of materials are used to build the pump? How do I know that the diaphragm won't dissolve when it sits in avgas for six months? I agree that the price of a new AC fuel pump is outrageous, but when you buy one, it will be made out of the right materials, and there will be a part number on it that is matched to your engine, and if need be, you would be able to verify what materials were used to build it. How do we know all that? Because the manufacturer is LIABLE for an aircraft quality pump that is to be installed on an airplane engine that carries people over the mountains at night. If his pump fails and someone dies, he gets to spend 5 years in court and then go bankrupt and then he gets to take up selling used cars for a living. The guy who makes the substitute part in China doesn't have to worry about all that. And he doesn't.
<<Functionally, ours is a TRANSFER pump. There is an hour find a place and land if it fails, presuming you buy a rainproof gauge, mark the "full" indication and observe any descent therefrom. Failure is not uncommon, but more of an inconvenience than an emergency if the gauge is properly monitored.>>
Unless the arm falls off the pump into the engine and trashes the engine. Or unless the pump diaphragm ruptures and lets fuel leak into the engine, dilutes the oil and causes the engine to seize. And based on my own experience, I would say that failure is very uncommon. I've never had the pump on my Alon fail. Of course, I do put a new pump on the engine about every 3 years whether it needs it or not.
<<Rebuilding our pumps ain't rocket science. Automotive maintenance manuals contain full details. If our auto fuel pump rebuild kits were available today, I would not hesitate in the slightest to use compatible components (like the "approved" screen, etc. we must buy every annual for a C-note)! With regard to the differing arms, don't install one that's different (and verify THAT one was right)! Duh?>>
Verify it against what? Where does one get a copy of the drawings that show what the arm and pivot mechanism dimensions are? If I remember correctly, there is no part number on the arm itself, and if someone installed a pump from a Case tractor the last time the pump was replaced, there's no telling if the one that is there has the correct arm on it or not. Is the difference between the various arms a matter of a few thousandths of an inch, or is it more noticeable? What about all the angles and contours on the arm? I don't know the answers to those questions. Maybe I'm the only one who is in the dark on this. Am I the only one who can't tell by looking at a pump arm which lobe diameter it is designed to ride on?
<<Any presumption a competent mechanic today is less capable of routine work than his counterpart of yesteryear is as ludicrous as it is offensive.>>
I agree. I wasn't implying that a mechanic is less capable today than yesteryear of doing routine work. But if I find out my mechanic is doing back yard engineering on my plane and going down to Lowes or Pep Boys and finding substitute parts for my airplane, he won't be my mechanic for long. Part of being a competent mechanic is realizing that there is often a lot of engineering behind the design and selection of aircraft parts, and realizing that you might not know everything that there is to know about a given part or application.
<<Our problem today is that new (and rebuilt, if still available) pumps are from a sole source. Parts are not sold. Absolute power corrupts absolutely, and current prices represent nothing less than legalized extortion. Skyport and Aircraft Spruce must pay whatever is asked, and sell at a reasonable profit.>>
Yes, the parts are expensive. To be honest, I don't really understand why any of the manufacturers are willing to sell a fuel pump for only $250, when they know that they are going to be sued for $5,000,000 dollars the first time a plane crashes with their pump installed. I guess Cessna is legally extorting everyone who buys a plane from them. How else can anyone explain a Cessna 172 selling for over $150,000? The truth is that the selling price has to cover the costs of the business risks. Building fuel pumps and other aircraft parts in today's legal environment is a risky business. Just ask the people who built the fuel selector valve in John Denver's Long-Eze. No, wait, that company doesn't exist any more.
<<Putting an aircraft part number on an automotive pump design does NOT retroactively make the automotive pump an "aviation" item. The "right" auto pump remains legal, as do its parts. Benjamin Franklin put it this way: "If you call a steer a bull, he's thankful for the compliment; but he would much prefer the restoration of what was rightfully his". Words alone don't change reality.>>
The reality is that you can't go to an auto parts store and be sure that you are buying the same pump, made from the same materials, as was originally specified for your engine. There is no traceability and no quality assurance. Again, if I'm wrong, what's the correct part number for the automotive pump for my engine?
<<The brake reservoir on the prototype Ercoupe was fabricated from a Pet milk can. These same cans were ordered in quantity for modification and installation on production Ercoupes. I believe the specific brake cylinder chosen was an automotive one, as was the brake fluid, landing gear bearings, the battery, the oil pressure gauge, ammeter, starter pull, mixture cable, cabin heat cable, cabin air cable, electrical fuse, fuse recepticle, paint, and upholstery, ad infinitum.>>
Agreed. The factory determined which parts were suitable for what. And today, if the proper aircraft part isn't available, and if someone who is qualified selects or builds a suitable replacement, and as long as it's entered in the logbooks and legal, then I have no problem with it. The fact that they entered it in the log books and made it legal either through a 337 or whatever is required means that at least they gave it a little thought and that they are standing behind their actions. What I do have a problem with is someone using their "common sense" and taking out the old Pet milk can and replacing it with a cardboard milk carton in order to save weight. Think that's ridiculous? Maybe so, but a few years ago, I got a letter from a guy who put two plastic 5 gallon gas jugs in his Alon baggage compartment and had it all set up with hoses and valves so he could fly long distances without stopping for gas. That made good common sense to him! It sounded like a flying fire bomb to me. Where do we draw the line on who gets to do the engineering?
<<The muffler clamps used on the Ercoupe have varied quite a bit over the years, and included AUTOMOTIVE clamps (sold with FAA oversight and added expense) distinguishable from ordinary automotive ones primarily by price...most certainly not by any design difference. Look at Ercoupes at the flyins, and a third or more show clear signs of exhaust leakage, without regard to what type exhaust clamps are installed.>>
I've always assumed that exhaust leaks were supposed to be found and fixed during annual inspections if not sooner. I just sent one of my exhaust stacks to Dawley aviation to have the flanges replaced because the old ones were slightly warped and were leaking a tiny bit at the gasket. If I'd known that exhaust leaks were an OK thing, I could have saved myself $150.00. Is it common sense that a tiny little exhaust leak won't cause any problems, or is it common sense that if there's an exhaust leak of any size, it gets fixed? My kids fly in my airplane. It gets fixed.
<<My personal opinion is that the prewar Ercoupes with individual unmuffled stacks (on the A-65), and later similar exhausts installed on Alons and M-10s are MUCH safer and lighter than the postwar muffler design with joints on each side of a (hot) muffler jammed right against the firewall. If so much air didn't race through Ercoupe and Forney side window and other gaps, many more of us would suffer carbon monoxide poisoning from associated exhaust leaks.>>
I agree.
<<A caution for the medical profession is "First, do no harm"! To that one could add "always use common sense". Now, would so labeling parts boxes (whether "approved" or "unapproved") improve aviation safety? OF COURSE NOT!>>
What someone thinks is common sense might be a recipe for disaster. Example: Back in the 70's my father was building a Smyth Sidewinder homebuilt. One of the other builders that we knew decided that the main wing attach bolts looked too small in diameter and he was asking about using a larger sized bolt just to be on the safe side. Luckily he wrote to Jerry Smyth, the designer, and told Jerry about his plans. Jerry Smyth's response was something like "Oh my GOD, whatever you do, Don't do that!!!" What the back yard engineer didn't know was that the weak part of the spar attach joint was the aluminum spar material around the bolt hole, not the bolt. Putting a larger bolt in would have removed spar material and caused the joint to fail at much less than the designed load. My father had the equipment at work to test the joint structure with both the designed bolt and the larger bolt. He had both joints pulled apart on a testing machine and guess what? Putting in that bigger bolt would have resulted in a case of "common sense induced death". If all it took to design a machine like an airplane was "common sense" then I suspect we'd all be flying around in our own low cost F-16's.
<<Does anyone REALLY believe a OSA gauge, VSI, cabin vent, shoulder harness, fireproof cushioning, CHT, EGT, circuit breaker, carb ice detector, or portable radio, headset or GPS should be of "approved" (TSO) design? One thing common to all these is that NONE were standard on a production Ercoupe. >>
Maybe not, but do you want to unknowingly buy or fly an airplane that has half of the electrical system built out of junk purchased at a flea market? I agree that there should be an easier way to get things approved. I spent 4 months wrestling with the FAA over allowing me to install an analog voltmeter in my airplane. It wouldn't have been a problem, except that according to the local FSDO only a TSO'd voltmeter can be installed. Well, the fact of the matter is that a TSO has never been written for an analog voltmeter. Therefore there are no TSO'd analog voltmeters in existence. The local FSDO finally relented and let us put a non-TSO'd one in with a logbook entry "if the mechanic would accept responsibility for the installation". That whole experience was a real pain in the back side. Interestingly enough, the voltmeter that I installed was built on the same assembly line, using the same techniques and some of the same parts as a similar TSO'd OAT gauge. The company (Westberg or Westach, I don't remember which) said that they would have TSO's the voltmeter, but there is no TSO document in existence for the voltmeter. (There is a TSO document for an ammeter though, and you can buy a combination ammeter/voltmeter that is TSO'd.)
<<ALL OF THEM IMPROVE SAFETY OF FLIGHT if installed and functional. Installation should be encouraged by being easy and inexpensive to do. TSO compliance and expensive engineering for each 337 on each airplane increase complexity and expense. More $$ = fewer installed. When bureaucracy adversely affects safety, something clearly and terribly wrong is happening.>>
I agree with you except that only qualified people should be allowed to say what's safe and what isn't. The world of homebuilding is designed for people who want to experiment to their heart's content. And to tell you the truth, after all the headaches and paperwork that I had to go through to get stuff signed off and approved when I restored my Alon, I think my next plane is going to be a quick-build RV-7A. (Just don't tell my wife that I said that!)
<<I am still waiting for someone, ANYONE, to explain to me the difference in danger either to occupant or to the general public below between a properly constructed homebuilt aircraft and a properly constructed type certificated aircraft, each (properly) owner maintained and flying from point A to point B.>>
<<I am still waiting for someone, ANYONE, to explain to me the difference in danger either to occupant or to the general public below between a properly constructed homebuilt aircraft and a properly constructed type certificated aircraft, each (properly) owner maintained and flying from point A to point B.>>
There is a difference in the safety levels. The fact that the typical homebuilder has a total manufacturing experience of one plane, and the factory has the experience, service history and continual improvements developed over hundreds or thousands of airplanes has a lot to do with the safety numbers. Look at the safety statistics and insurance premiums. But the homebuilt says EXPERIMENTAL on the side in big black letters, so each individual climbing aboard can make his or her own decision about what risk he is willing to take. And I know that there are lots of homebuilts out there that are built much better than any factory could ever hope to produce. I've also seen some that were accidents looking for a place to happen.
<<The single "justification" for the FAA looking over our shoulder all the time was to "regulate air commerce". Since they have been successful beyond their wildest dreams in eliminating any possibility we, the people, with a "mere" private license might make money (or even break even) with that piece of paper, perhaps it is time to petition Congress to recognize that private aviation has ceased to be "air commerce" in any way, shape or form. If high-paying American jobs with full benefits must be eliminated, let's start with the FAA! >>
<<The single "justification" for the FAA looking over our shoulder all the time was to "regulate air commerce". Since they have been successful beyond their wildest dreams in eliminating any possibility we, the people, with a "mere" private license might make money (or even break even) with that piece of paper, perhaps it is time to petition Congress to recognize that private aviation has ceased to be "air commerce" in any way, shape or form. If high-paying American jobs with full benefits must be eliminated, let's start with the FAA! >>
Lockheed is working on that and is making excellent progress......
<<Before Fred died, he confided with me that back when he was designing the Ercoupe no one in aviation would have dreamed in their worst nightmare that an agency would eventually evolve with as many employees as licensed pilots. I am amazed each day we pilots continue to meekly accept such a ridiculous state of affairs without question or objection.>>
<<It might be easier for me if I believed the sky to be "theirs", instead of "ours".>>
<<Before Fred died, he confided with me that back when he was designing the Ercoupe no one in aviation would have dreamed in their worst nightmare that an agency would eventually evolve with as many employees as licensed pilots. I am amazed each day we pilots continue to meekly accept such a ridiculous state of affairs without question or objection.>>
<<It might be easier for me if I believed the sky to be "theirs", instead of "ours".>>
Don't let 'em fool you. When the wheels leave the ground, the sky is indeed "ours"! Like they say, they can't do anything to you until after you land! Well, as long as you can outmaneuver an F-16!
<<(off soap box)>>
OK, now I'm off the soap box. It's your turn! Next time we see each other at a fly in we will have to buy each other a Coke in celebration of breaking all soap box endurance records. (If we've worn this subject out, we can move on to the auto fuel vs avgas thing. Not!)
Best Regards,
Wayne DelRossi
Alon N5618F
Alon N5618F
Hours logged since restoration: 44.7
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