Author: William Wynne

I have been continuously building, testing and flying Corvair engines since 1989. Information, parts and components that we developed and tested are now flying on several hundred Corvair powered aircraft. I earned a Bachelor of Science in Professional Aeronautics and an A&P license from Embry-Riddle Aeronautical University, and have a proven 30 year track record of effectively teaching homebuilders how to create and fly their own Corvair powered planes. Much of this is chronicled at www.FlyCorvair.com and in more than 50 magazine articles.
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Adjustable Front Starter Bracket

Friends,

Below are photos of our latest evolution on front starters. Since 2002, the only starter arrangement that we have worked with is the front starter. Originally we used hand prop engines, moved to front starters in 1992, Developed and flew the rear starter in 1998-2001, and then came back full circle. In the last 10 years we have refined the front starter several times to make it lower profile (2003), use machined brackets instead of welded ones (2006), switched from welded on ears to bolted on ones (2010), and now we have changed the ear to a single piece bracket with an adjustable slot which eliminates the previous drilled aluminum link. installing a starter now takes a few minutes with three wrenches. No drilling or fitting. If you crank it up and it doesn’t mesh with the sound of prefect engagement, a minute of loosening the bolts and resetting the adjustable bracket will make it correct in no time.

Above, the new bracket bolted on a starter mounted on a 3,000cc Corvair equipped with a Dan Bearing. In the last two years, starters we have sent out have had the front ear bolted on instead of welded on. any of the bolt on ear starters can be retrofitted with the new bracket. The above photo is of the same engine we had on display at Sun n Fun. A number of builders asked about the starter, saying it looked smaller than previous models. It was an illusion; This is the same EA-81 based ND starter we have used for the last 10 years. The main visual difference was that I painted this one black and spent 15 minutes on the band saw removing the shroud around the starter gear. The new bracket has a cleaner look than the previous system, but the concept is the same one that has started 100’s of Corvair builds in the last 10 years. The improvements have been small and evolutionary. I have had much better experiences with things in aviation that are refined and slowly evolved to be what the are rather than things that are new and revolutionary. We can all think of things that are revolutionary success stories like the Vari-eze, but you have to remember that it was the exception. In the 1970s there were dozens of other new revolutiary airframes that didn’t work out, like the BD-5. I like to read about new and exciting things, but I have been much better served by things that are old and proven.

Above is a photo of two dozen of the new brackets. They are CNC machined for accuracy from 1/4″ 6061-T6 plate. At the bottom of the photo are two different spacers. These move the starter forward slightly when installing a Dan bearing. If you look at the top photo, you can see the small spacer between the new bracket and the left hand side gold anodized starter bracket. We have these spacers and pre-machined tail brackets for engines that are assembled with Dan bearings. The tail bracket is visible in the top photo.

-William

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Distributor Detail

Friends,

There are a lot of little details on Corvair installations that are best shared in a picture and a few sentences. Below is a distributor clamp, installed as we prefer, on a 3,000cc corvair that we built.

Above, the proper orientation of the three parts of the distributor hold down.

Every now and then I inspect a Corvair engine assembly where the builder has the incorrect clamp, or has it improperly installed.  First the nut; the stud thread is 3/8″-24. In its stock form, the nut is a regular fine thread nut. In the car it is unlikely to back off because the little wire clamp effectively spring loads it. In the plane we are not going to count on this. The best nut for the job is an MS21042-6, something you can get from any aircraft catalog. A regular all metal lock nut will often have it locking feature above the top of the stud. The MS nut is low profile and the fact it takes a 7/16″ wrench makes it easier to tighten. (This is the same nut we use on the hybrid studs to hold down the prop hub.)

 Under it is the stock GM square washer. It has two little ears that face down to keep the wire from spreading when you tighten the nut. A regular washer will not work here.

Under it is the GM wire style clamp. These are far better than any other type of distributor clamp. When you put the pressure on them the two ends of the clamp make very firm contact with the distributor housing, and then the wire deflects as a little spring. I have never seen one of these move once it is tightened down. The reason why the two parts look shiny is that we have the ones on engines we build nickel-plated for corrosion resistance.  A quick shot of spray paint will have the same effect on engines assembled in home shops.

-William

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Flying 2700 cc Zenith 601 XL(B), Alan Uhr

Friends,

Below is the 601-xl of Alan Uhr, of central Florida.  About a week ago I got on the motorcycle and rode 150 miles down to his airport to pay a house call. I gave Alan and his son a hand installing an E/P distributor to replace the dual points model that they originally used. The trip gave me a chance to see the plane first hand. In our industry, very few companies have the HMIC, (head monkey in charge – me) pay house calls to builders. The goal of most companies is to just sell things, and they place very little value on inspecting progress of builders. Conversely, our goal is to teach builders, and thus personally inspecting their progress in the field is critical to understand their needs and evaluating how well our instruction methods are working.

In a recent conversation, a magazine writer told me that he “Had his finger on the pulse of experimental aviation” because he read “all the important web discussion sites” and went to many airshows. I have been part of experimental aviation for more than 20 years, and I a pretty sure that no one ever completed a plane by sitting at a computer, and the only plane I have ever seen built at a show was when Zenith used to build a plane in a week at Sun n Fun. There are some useful things on the web, but they are most often lost in a sea of disinformation and negativity, and the Zenith factory team is not typical of homebuilders working in their shops.  Reading sites and going to shows gives a very distorted view of experimental aviation. You can find out what people are talking about or buying, but this has little to do with actual building. We don’t call it homeTalking nor do we call it HomeBuying, experimental aviation is HomeBuilding, and to find out what people are building, you have to go to their shops and see it in person, and listen to them. Over the years, I have made several hundred house calls to builders. This is a good measure of my actual contribution to the success of fellow builders, and of my understanding of the state of rank and file homebuilding.

Above, A side view of Alan’s 2700cc corvair. It has flown about 40 hours. Initial progress was slow because Alan mistakenly had a MA-3 from a 145hp-O-290 Lycoming instead of the MA-3 from an O-200 contential, as we specify. The correct model number is a 10-4894.  Alan went direct to D&G in Niles MI for the correct carb, and instantaneously the engine ran vastly better. Many people don’t understand that too large a carb on an engine will often run way too lean, not too rich. A very large venturi and oversized idle circuit tends to have a weak pressure signal to the fuel in the bowl. Before the incorrect carb was diagnosed, Alan was besieged by local “Experts” who tried to talk him into changing every other aspect of his installation, even though none of them had ever seen a Corvair in a plane before. To me this is akin to a veterinarian offering neo-natal advice to a mother. Children and dogs are both mammals, but the detail advice is crucially different on some points. Corvairs and Lycomings are both engines, but the details differ, often in ways that are not good for your heath to ignore. If any one needs advise on a Corvair installation, I am a better resource than your local “Expert.” If your child has fleas, I am of no help, but I would suggest the MD over the Vet.

Above is the rear view of his installation. It has a complete heavy-duty gold oil system and a Niagara cooler. Alan’s aircraft is very much like the other 45 Corvair powered Zeniths that have been flown by our builders. Let me use this to point out a very basic, but critical concept in homebuilding.  Woody Harris and Phil Maxon, who each have nearly the same corvair powered Zenith as Alan, can and have flown their planes literally around the USA without issue. Either Woody or Phil could push their planes out of their hangars today and fly to the opposite coast of our continent at will. We have plenty of other Zenith flyers Like Lynn Dingfelder, Dave Garda and dozens more who can do the same.

Here is the critical point: When Alan was having an issue, His local “experts” ignored the fact that plenty of other people are very successfully operating the same combination of airframe, engine and systems. They all wanted to redesign everything. Conversely, the approach of any actual mechanic is to look at a proven plane like Woody or Phils, and then carefully study what is different about Alan’s, and then only change that to make the plane identical to the proven working ones. Aircraft do not love you, and they do not play favorites, and the have no prejudices nor pet peeves. They are machines, and they owe 100% of their loyalty to Physics, chemistry, metallurgy and aerodynamics. If plane A works perfectly, and plane B does not, all you need to do to fix this is to detect the differences between A and B and then make B just like A. Understand that this strategy isn’t just likely to work, or even almost certainly going to work, It is absolutely going to work. 

Most people in aviation have flown in a Cessna 172, and know they have a 50 year track record of being a trustworthy aircraft. When a 172 comes in for an annual, all the mechanic is doing is looking to see how that particular 172 is different from the specifications from the type certificate and then he goes about making the plane back to the known accepted standard that has proven to work. It is a skill, but the concept isn’t deeply philosophical. The mechanic doesn’t get creative and offer to reconfigure the fuel system, he just makes it identical to the ones that are known to work. Just because a plane has the word “Experimental” painted on it, doesn’t mean that the rules of reliability go out the window. The plane can’t read the word experimental, but it is smart enough to know that it is only going to respond to the laws of physics, not the psychology of local “Experts.”

Above, a side view of Alan’s plane. He has a very good background in Gyrocopters and is a pretty good craftsman. The aircraft demonstrates very nice workmanship in person. I have known Alan for a number of years, and he is a very good guy, exemplified by his positive attitude.  Although he had some frustration moments in getting is aircraft squared away, he never lost sight of the big picture, that he had persisted to achieve what many people start, but far fewer finish, building a plane with ones own hands. Hats off to Alan Uhr, Corvair builder and pilot.

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In Search Of … The Economical Carburetor

Friends,

There are a lot of smaller research projects that we work on during a year. One of these that I had kicked around in discussions with Dan Weseman was the potential to use an off the shelf, one barrel automotive down draft carb. Although both Dan and I have made a lot of high-end stuff for Corvair conversions, we are both still interested in keeping the engine and it’s applications affordable. Ma-3 and Elison carbs run about $950 overhauled or new. The are great and serve an important purpose. Stombergs are $250 to $550, and are a very good choice for gravity feed planes. Aiming lower, we are moving into the possibilities of  Zenith 268 carbs and motorcycle units. Neither of these offer a significant savings over Strombergs.  I am not a huge fan of carbs without float bowls. Aerocarbs, Revfows and Posas have all flown on Corvairs, and they have their fans, but most builders would like a carb that has a float, or a design like the Elison or Rotec that stops flowing fuel when the engine is shut off.  I have owned and operated all of the above carbs, and I will gladly say that float carbs are much more accurate at metering fuel. 

Below, what we are looking at is a Carter 1 barrel from a 170cid Ford straight six. I bought this carb in a box from Discount auto parts for $149, and paid an additional $10 core charge. This is about as inexpensive as you will ever see for an overhauled carb. The concept here isn’t new. 15 years ago we tested one single barrel Corvair carb and found that it could produce more than 85HP on the right manifold.  This Ford carb is significantly better flow potential than the Rochester HV. If you go to our main website and look at the category of flying planes, Dale Jorgensen’s VP2 has been flying for more than 10 years on a single down draft taken from a Chrysler slant six.

Above is a shot of the manifold on the test stand. The test engine is a 3,000cc, 120 hp engine. It makes a good test here because we want to know if the carb is operating near its flow potential. I am guessing that most of the people who may be interested in a Ford carb would be building a 100hp engine, and if the cab demonstrated that it could produce a solid 90 or 95 horses, this would be plenty. This manifold was made from one of our regular cnc bent manifold tubes. The box under the carb is 1.5″ x 3″ tubing. There is a lot of initial reaction to guess that such a flow pattern would be restrictive, but in practice, it matters a whole lot less than most people suspect. We are building a manifold for a 3,200 rpm engine making .65 HP/cid, which is very different from making a manifold for a 160HP sport bike that needs instantaneous throttle response.

Above, the carb mounted. The small red lever is a lawn mower throttle arm rigged to run the choke, in a plane this would be done by a cable. Looking at the carb, think of these thoughts: It can take fuel pressure; the inlet fitting is 1/8″NPT, not a brass nipple for fish tank tubing; It has a choke; It has an accelerator pump; It has robust construction and has a low parts count. The only downside it that it doesn’t have an easy way to control the mixture in flight.  If you want to fly at 15,000′, this is an issue. If you want to use this on a Pietenpol, it probably isn’t. In the years we had our Piet, I can’t recall ever having the plane over 6,000′ MSL, and I would guess that it spent 95% of it life below 3,000′ AGL. It had a Stromberg, but the mixture was wired in the full rich position. I would lay a serious bet that 100hp Corvair in a Piet with no mixture control would have a much higher service ceiling than a an A-65 or 75 Piet with the most elaborate mixture control.

Above is the carb running on the engine. Initial results are very positive, It starts right up and runs well. It idled very smoothly at 650rpm, and I could probably get that a lot lower with some carb heat and a finer adjustment. I am going to install a different EGT set up and a 5 psi electric pump to do a little more testing. We will have more results and the system on display at Corvair College #23 next month.

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Andy Elliott- Corvairs, airborne and land-based.

Friends,

Corvair builder and Pilot Andy Elliot sent in the following note and photo:

WW:

Last weekend, I offered to help out someone who needed a lift up to Page, AZ (KPGA) for a trip to the Antelope Slot Canyon on the Navajo Reservation. Imagine my surprise when he rolls up to the hangar in a renovated 64 convertible! Couldn’t resist taking the attached pre-flight photo. Beautiful, smooth air night flight back also, with about a 46% moon directly overhead.  I thought the pic would be nice for your website!

Andy Elliott – N601GE/Z601XL/TD/Corvair -435 hrs since 11/08

Web Site Link

Check out the previous stories on Andy’s aircraft by looking at the  Flying Planes heading on this site, or searching his name at the bottom of our main page, FlyCorvair.com

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Corvair College #23 – 40 Days away

Friends, 

 We are now just 40 days away from Corvair college #23.  Dan and I are putting  a lot of prep work into this event to make sure that every builder attending gets the most out of the event. We have developed specific checklists for each builders goals to allow them to come prepared for progress.

When you sign up for the college, please directly email me a paragraph or two on your plans, and I will gladly send you information on the specific items you will need. Please include a phone number, as I can often cover some variables faster on the phone. We will also use this information to break the builders down into smaller groups and organize some specific instructional sequences aimed at small groups. For example, a I going to show everyone in attendance how to use a timing light on a running engine, how to install a distributor, and how to set valve timing. We are going to do this in groups of 4-5 people to make sure that everyone learns these skills hands on.

Having Dan, Mark Petz and Myself on hand means that we can cover this, even for a large number of builders. We have other experienced builders like Dan Glaze, veteran of several colleges, returning to assist builders with tasks like exchanging engines on the run stand. Even though we are aiming for a large turn out, the expert to builder ratio will still be very favorable for good individual progress.

The link to the registration page for CC#23 is: https://corvaircollege.wufoo.com/forms/corvair-college-23-registration/

If you have not been to one of my previous Colleges, take the time to read about any of our Colleges from this section of our Web site: http://flycorvair.com/cc21.html

College #23 will be run just like previous events where the primary focus is on the progress you will make on your own engine. After 12 years of Colleges with hundreds of builders in attendance you can find countless stories of the value of attending a college, told by builders just like you. Don’t let this opportunity pass you by.

Question: What kind of person attends a Corvair College? Answer: All types of characters do.  Above is a picture of a Corvair crankshaft core that arrived in our shop, sent by Corvair College #22 builder Kendal Darter. It is part of a batch of cranks that we are having processed as a group for CC#23. When a crank arrives wrapped an embroidered sweatshirt with a Crown Royal bag over each end, you can safely call the builder a character. If you local EAA chapter is light on serious builders, or if you consider yourself a little out of the mainstream, sign up for Corvair College #23, you will fit right in with the broad variety of serious builders that will be at the event.

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Corvair College #23, June 8,9,10 – Florida

Friends,

We are two months away from the next Corvair College.  We are holding it in Palatka, Florida. This town is about 30 miles south of Jacksonville. The airport is a large municipal airport with long paved runways and fuel. It is uncontrolled and fairly low traffic. The airport is called Kay Larkin, named for a WWII aviator.

In the next week we will have more updates on lodging and camping, a specific schedule, and detail information. For today, I would like to get the registration link up, and let builders know about an important deadline that is a week away.

Dan and Rachel Weseman are co-hosting this College with us.  Mark Petz from Falcon is also flying in for the event. Because the College is in Florida, we expect a large turn out. Because the location is close to both our hangar and Dan’s we are going to have access to every tool we may need. Dan and I are developing a schedule for the event that will give it more structure, which will allow new guys to get more out of the large event. We will post this schedule in the next two weeks.

With these assets, we are planning on getting many builders through the closed case with a Dan bearing on it stage. For builders to take advantage of this, they have to order a bearing from Dan this week, so that he can get a large order in with his machine shop, for delivery at the College. Additionally, Dan has developed a first class complete service for crankshaft work. If you are a builder at home with a core engine, and you would like to be one of they guys going home with a lot of work done, this is the week to send your core crank to Dan and order a bearing. You can directly contact Dan on this at this link: http://flywithspa.com/corvaircomponents.html We should be able to cover more than 15 builders on this, but it takes having the parts processed now to make it happen.

The link to the registration page for CC#23 is: https://corvaircollege.wufoo.com/forms/corvair-college-23-registration/

If you have not been to one of my previous Colleges, take the time to read about any of our Colleges from this section of our FlyCorvair.com Web site: http://flycorvair.com/cc21.html

College #23 will be run just like previous events where the primary focus is on the progress you will make on your own engine. After 12 years of Colleges with hundreds of builders in attendance, you can find countless stories of the value of attending a College, told by builders just like you.

If you have not made the progress you planned in the past year, change your approach, sign up for this event, and take a positive step in starting this year off with a plan. Attending a College is the #1 cited milestone mentioned by people who are out flying their own Corvair powered planes today. Don’t wait to see if this year will be different: Make it different.

Corvair/601 builder Ken Pavlou, aka The Central Scrutinizer, has set up the online registration for #23. Ken has covered this on 7 of the previous 9 Colleges from his workshop in Connecticut. His work is an outstanding example of builders making a contribution to the Corvair movement. I will be back online over the next few days with further updates on CC#23, feel free to write in with any questions, I will cover them here.

Thank you,

William

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Sun N Fun 2012

Friends,

Sun N Fun 2012 is now in the history books. This was my 24th consecutive year at the event. Many people wanted to know how it went, asking about the new president’s efforts to improve the event and the lingering effect of last year’s tornado. The answer largely boils down to a success story. The crowd was about the same as it has been from 2007 onward. (The peak year for attendance at Sun N Fun is rumored to be 1997 or ’98.) My particular observation was that the crowd was smaller, maybe 80,000 people, but I thought they were quality people. Almost everybody we spoke to had a sincere interest in aviation, and many of them specifically stated that they came to Sun N Fun to learn something. This is always a good sign.

I rarely measure the success of an air show by gross sales. The number can be very deceiving if you happen to sell two or three complete engines. For me the real measure of any airshow is the number of new Conversion Manuals sold. These represent fresh builders entering the Corvair movement. With fluctuations in the economy, builders will accordingly take a longer or shorter time to work their way through to a complete engine. Once they get started, I have a really good track record of keeping people motivated with new information and events like the Colleges. By this measure, 2012 was a very healthy year for Sun N Fun, selling more Manuals than we have in the past three or four years.

As guests in our booth this year, we had Dan and Rachel Weseman representing their newly formed company, SportPerformanceAircraft.com. Most people in the Corvair movement know Dan as the builder of the Wicked Cleanex and the developer of his very popular fifth bearing. Dan’s current project is his new single seat Panther aircraft. He had a completed wing on display along with a fuselage, tail cone and landing gear. All of the engineering and drawings for the design are complete. He is fabricating the prototype over the next few months and then will begin testing. He had no Panther parts nor drawings for sale at Sun N Fun, Dan and Rachel just wanted to bring it out and show people in person what the project looked like. If possible, they are shooting to fly the aircraft before Oshkosh this year.

Below are a collection of photographs we took at Sun N Fun. As usual, they are mostly about people. While we bring a lot of interesting hardware to shows, invariably the most interesting thing that’s in our booth are successful builders who are there to share their experience with those just starting. Sadly, many aviation companies do everything they can to keep the people who have purchased their products from meeting people who are considering buying them. They wouldn’t look very good if their previous buyers were asked for a testimonial. When you’re looking at all the photos below, consider that our efforts with the Corvair movement are just the reverse of this. The strongest motivator to the new builder is one of our experienced ones.  Next time you’re at an air show, observe this phenomenon and you’ll have a really good litmus test of any business or product you’re looking at.

2012 is the 52nd year of Corvair powered flight. This means that Corvairs have been in the air for about half of the history of powered flight. The first half of the Corvair’s history was largely dominated by the story that Bernard Pietenpol wrote. His work was the greatest single factor in the success of the engine between 1960-85. In these years, he led the vast majority of builders to the finish line with a simple engine conversion that proved to be very smooth and reliable. My work with the Corvair has been evolutionary on top of his. Although many of the things we have done with the engine are very diverse, sophisticated and advanced compared to Bernard’s work, I never discount the fact that his pioneering efforts paved a path that made my work possible.

One of the first questions that tire kickers and journalists ask when they meet you at an air show is   “What’s new and exciting?”  My answer is always the same “Nothing. Why don’t we talk about what is old and flight proven?” 

The word “new” to me in its aviation context is synonymous with the term unproven. I find “exciting” a very good term to describe the discovery that an unproven component is unreliable. The Corvair has been tested in the crucible of experimental aviation for the past five decades. What can and cannot be done with the engine is well defined and understood. Proven engines have been long flown and are easy to replicate. Only a very naïve person would look at any engine newly introduced to the marketplace and somehow feel that it will not experience any type of developmental or teething problems. Even if the engine itself is an outstanding piece, there will still be installation issues to define, and builder practices to develop. I defy any experimental aircraft builder to show me any engine that has not gone through this process. Here in the sixth decade of homebuilding, to suddenly expect any engine to arrive on the marketplace and be the first to have zero introductory issues is simply unrealistic. Some of the issues will require a simple service note and a change in practice, others will require the influx of cubic dollars that many of the businesses do not have. In the land of Corvairs, we are well beyond these points, and builders selecting the Corvair can proceed with confidence that can be attached only to a few engines such as the O-200. I firmly believe that people are entitled to spend their own money and time on any engine that they like, and if they wish to pursue new and exciting, they should. The aim of my work is never to be new and exciting, it is always been to be old and proven. This is the primary philosophical difference between myself and many of the other engine gurus. Experimental aviation has many choices, and builders need only find the one that matches their own needs and perspective.

 

From left to right above: Charles Leonard, who has been flying his Corvair powered 601 for five years; Dan Glaze who completed and test ran his 2700cc/Weseman bearing engine at Corvair College #20, which is destined for his CH 750; Dick Holtz, who is working on completing his 3,000cc/Roy bearing engine at Corvair College #23 to be installed in his Just Highlander; Dave Glassmeyer, who ran his 2,850/Roy bearing engine at Corvair College #20 and has plans to install it in his Kitfox Model V; and Dan Weseman of Wicked Cleanex fame brings up the other end of the frame.

On the left above is Gary Collins of Ohio, whose 2,700 cc Weseman bearing engine ran at Corvair College #20. Its ultimate destination is his Carlson Sparrow II project which is now 95% complete. On the right is  Dave Glassmeyer. In the background are some of the items that Dan and Rachel brought to display.

 

Dan with the fuselage of his Panther prototype. On the other side of the fuselage is Greg Jannakos of Georgia, who has been flying his Corvair powered 601 HDS for seven years. He recently retrofitted his engine with a Weseman bearing. Greg’s Zenith was the second one to fly, right after our own 601 XL. There are many pictures of Greg’s aircraft on our FlyCorvair.com Web site, dating all the way back to 2005.  We have now had eight years of Corvair powered Zeniths. With more than 50 of them flying, we are at the point where we can call them old and proven. New and exciting is fun to read about if you’re a tire kicker. If you’re a real builder, you can build a plan of personal success on old and proven.

Corvair/KR pilots Bob Lester, left, and Steve Makish, right. These two have been friends for decades. Between them they have about 800 hours of Corvair powered flight time. They both hail from South Florida. The first year that Steve flew his Corvair powered KR to Sun N Fun was 2000. Bob’s made it to the event the following year. If you have not spent time around these two guys, you’re missing some quality entertainment. The best way I have of describing it for people who are yet to meet them is that Steve is Bugs Bunny and Bob is Daffy Duck.  Picture the two of them yelling back and forth to Elmer Fudd: “It’s rabbit season!” “It’s duck season!”

Above is Dan Weseman at left, and Colorado Pietenpol/Corvair builder Rick Holland with our our 3 Liter display engine. Rick’s plane is nearing the finish line after a number of years of steady work. His engine features Electric Start, all our Gold Conversion Parts and a Weseman bearing. The 3 Liter display engine is destined for Lary Hatfield’s Zenith 750. This engine is equipped with a Weseman bearing and a set of Falcon heads. This is the same engine we were using to test a mechanical fuel injection system.  For display purposes at airshows, engines are equipped with a dummy Intake Manifold and carburetor and a sealed Exhaust System. This allows builders to understand the relationship of these components and installation, but effectively seals the engine from any type of dirt or moisture.

 

Above, the lovely Sandrine and Mark Meehan, Corvair builders from Orlando, Florida. A great team, very inspiring.

Above, Joe Horton, left, and Lynn Dingfelder, right, both of Pennsylvania, inside our booth. Joe again flew his KR-2S all the way down for Sun N Fun. His aircraft now has about 750 hours on it. It is powered by a 3,100 cc Weseman bearing engine.  Lynn’s aircraft is a 601 XL. It has a 2700 cc Weseman bearing engine, and has been flying since 2008. Both of these men have gone out of their way to return to Colleges and airshows and share their experience with Corvairs with other builders. Very few other products in aviation have this type of spirit associated with their use.

Above is a look at our booth. In the foreground in front of the trailer is the Panther’s completed test wing.  Renting a booth at Sun N Fun, plus paying for the tent and the camping, runs several thousand dollars. With all the prep work, the setup, the week’s display, the travel time, and the packing, unpacking, packing and unpacking, you’re looking at a two-week commitment. Yet face-to-face meetings with builders and giving them a chance to meet successful builders and pilots is a very important part of the Corvair movement. In a previous post I mentioned that most alternative engine LLCs have a three-year lifespan where they show up, take a lot of money, milk it for a while and then disappear. 2012 was no different. Missing from the scene were a number of here today gone tomorrow LLCs. A customer of one such firm actually stood in our booth briefly and told me that he was looking forward to getting some technical answers from the people he bought an engine from last year.  He politely asked us if we had seen where their booth was, as he could not find the business name in the air show directory.  I took little pleasure in telling him that the business that he was looking for had evaporated months earlier. I don’t think he actually believed me, as I later saw him asking pretty much the same question at a different engine display.

You never know what will turn up at an air show. Above, I sit in an extremely historic homebuilt, the McDonald S-20. The designer stands by the wing. Although I have never seen the aircraft before and the only pictures of it I know of are in a 40-year-old Sport Aviation, I recognized the aircraft immediately. McDonald was standing next to the plane talking to the EAA’s Charlie Becker. He was a little bit surprised that I could walk right up and identify the aircraft, and that I knew of many of the technical details in it.  He insisted that I  sit in the aircraft and appreciate the ergonomics of the cockpit, something he was particularly proud of designing. If you talk to people marketing things at airshows, even experimental aircraft and engines, many of them cannot tell you the difference between a Glasair and a Lancair. It may not be critical to their sales task, but it makes their claims of being in love with experimental aviation a little hard to believe. I will freely admit that there are many things about which I know very little: Computers, international cooking, agriculture, baroque art, matrix methods and laplace transforms, child rearing, and a staggering list of other topics. But when it comes to homebuilts, I know the subject quite well and have a great appreciation for its finest examples. 

Above, Corvair/601 builder Phil Maxson from western New Jersey. Phil flew his plane down to Sun N Fun, taking the record for the longest Corvair powered flight to Sun N Fun 2012. He flew about 20 miles further than Joe Horton. Phil’s aircraft has been flying since 2006. His engine is a 2700cc/Weseman bearing engine. The YouTube video of his aircraft flying over the Florida coast has over 30,000 hits on it.

On Friday night, Dan and Rachel and I hosted  an informal cookout in the campground. We had about 30 people on hand, a nice mixture of old friends and new faces. In the foreground in the blue shirt is well-known Corvair pilot Gary Coppen.

On the left in the Hawaiian shirt is my primary go to guy for engineering and CAD work, Spencer Gould. Spencer is a fellow Embry Riddle alumni, who currently works for Pratt Whitney. His one-of-a-kind  Corvair powered aerobatic composite airplane was featured in an earlier Projects blog post here at FlyCorvair.net. In the blue shirt next to Spencer is Mick Myal, the founder and original editor of Contact! magazine.

One of the nice things about holding a relaxed evening in the campground is the fact that no one has to drive anywhere after the evening winds down. Dan and Rachel filled a couple of big coolers with beer and soda, and had a full-size gas grill running for a couple of hours. Half a dozen builders hung out until the wee hours of the morning. The following day Rachel pointed out to me that the donation jar came within six dollars of covering the several hundred dollar tab for the event. I take this as a sign that people had a very good time. The evening was a very nice addition to several years of informal barbecues for Corvair people at Sun N Fun.

In the blue shirts at the center are John Godwin, left, and Mike Oberlies, right. These two guys are well known for catering the barbecues at South Carolina Corvair Colleges. They spent all week volunteering in the workshop area of Sun N Fun. They’re both building Corvair powered Pietenpols that they are planning on finishing in 2014.  The diversity of characters attracted to the Corvair movement is really impressive. While I am sure the purchasers of Rotax engines are good people, I honestly doubt they have anywhere near the type of diversity in their ranks that we do in the Corvair movement. Building and flying planes is meant to be fun, and I find it most rewarding when it’s done in the company of some real individuals.

Above, another photo from the barbecue.  On the extreme left, in the pink Panther shirt, is the lovely Rhonda Weseman, Dan’s mother, and sheetmetalsmith from JSWeseman.com.

 

In the above photo, a Sonex builder next to Dan. We are having a good laugh disguising his identity because on his shoulder is a motor mount that mates the Sonex airframe to a Corvair engine, creating a “Cleanex.” Here we are kidding around about the  man in the yellow shirt entering “The Builder Identity Protection Program” because the combination is not approved by John Monnett, the airframe’s designer. In years past, John was known for having low tolerance for people modifying his excellent airframe designs. Truthfully, I know him fairly well and he really doesn’t get that upset about it as long as builders choosing other engines do not level unfair criticism at his selected engines.  There are now about 10 Cleanexes flying, and Dan is glad to work with any builder who has chosen the combination as long as they respectfully avoid Internet comments that would raise John Monnett’s blood pressure.

Above, old friends from the era when I was president and Grace was newsletter editor for EAA Chapter 288 at Spruce Creek. At left, Roy Shannon, and center, Steve Bacom Jr., both VariEze builders. On the right is Arnold Holmes, long time Corvair pilot and host of Corvair College #17.

 

Above, a photo of Joe Horton’s Corvair powered KR-2S out on the flightline. The aircraft now has almost 750 hours on it. I have very clear memories of Joe showing Grace and me photos of it under construction at Sun N Fun 2002. He has since flown the aircraft back to the air show a number of times. This type of experience is the definition of success in homebuilding. On the Internet tonight there are countless people who will talk about what they will do someday. For the great majority of them, someday will never come. The core of my work is to demonstrate a path to an affordable engine that is an integral part of a builder’s successful journey to the flightline. When you look at it coldly, everyone at home working on their plane tonight is going to end up in one of two groups: those who never finished or those who  will be keeping Joe company in the sky. The largest single factor in determining which group you will be in has nothing to do with money, experience, resources or time. The largest single factor is simply your ability to put some good decisions together and follow a proven path to success. This starts with rejecting the negative messages sent out almost continuously by people who themselves have not and will not succeed at homebuilding. A guy like Joe, who has been to the finish line, understands not just the skills and equipment required, but far more important the attitude and the perspective that got him all the way through. It’s your life and your decision, choose wisely. Homebuilding is intensely time and resource consuming, and it frequently doesn’t offer a lot of second chances. Any builder reading this can decide that this will be his year and he will have his day in the sun just like Joe.

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Mechanical Fuel Injection Testing

Friends,

One of the things that we have been testing lately is a mechanical fuel injection system from Precision, makers of certified aircraft fuel systems.

Precision has developed a single point fuel injection system that is entirely mechanical for engines in the Corvair’s power category. We have had one of these for several months and conducted a number of tests. Below is a quick outline of some of the data we’re collecting.

Above on the left is the Precision fuel injector, on the right for size comparison is an MA3-SPA Marvel Schebler carburetor, the most popular Corvair carburetor. The Precision injector is designed to fit in exactly the same space with the same bolt pattern as an MA3.

Just for starters, let me say that many people do not understand the function of mechanical fuel injectors on aircraft. The above unit is closely related to the operation of an RSA fuel injection system, the gold standard of mechanical fuel injectors. Part of what confuses experimental aircraft builders is the fact that there are a number of carburetors that include in their name the misnomer “throttle body injector” or “Aero injector.” Both the Ellison and the Aerocarb are useful carburetors but in no way shape or form are they fuel injectors. They are simply flat slide carburetors that do not have float bowls.

The defining characteristic differentiating a mechanical fuel injection system and any other type of carburetor is simply that the mechanical fuel injector meters off density, not off volume. Anything that meters fuel off the volume of air flow that comes through the throttle is a carburetor. Such systems will always change their air/fuel ratio as the density of air changes. Conversely, mechanical fuel injectors, such as the Precision unit, meter off density. When they are set to a specific air fuel ratio they hold it, no matter what altitude you climb to, nor how the conditions change. If you look closely, there are four chambers on the diaphragm of the Precision unit. These four chambers allow this to function as a very precise pressure regulator and metering device based on the mass flow of the air passing through the assembly.

To give you some idea of the quality of this unit, and its adaptability to different airframes, the directions actually spell out that it can be run on any fuel pressure unregulated between 20 and 80 PSI, and it will handle momentary over pressures to 180 PSI without damage. Because of the diaphragm assembly, the pressure can actually fluctuate between any of these pressures and it will not change the air/fuel ratio.

The primary difference between the Precision system, and typical certified aircraft systems, is that this is a single point injector that does not have injector nozzles in the intake ports. It has one nozzle that is in the body of the unit after the throttle plate. This unit is immune to carburetor icing. Yet in operation the fact that the fuel is vaporizing 18 inches upstream of the intake ports allows a very significant evaporative cooling effect. Unique to this unit is the fact that it is equipped with a very potent accelerator pump that gives it instantaneous throttle response that one associates with port fuel injection.

Above, the Precision injector mounted on a 3,000 cc Corvair on our engine test stand. Bolting on the injector in the place of our typical MA3 only took 30 minutes. Even the throttle arms are in the same location. As far as I know, this is the first mechanical fuel injection system that has ever been used on a Corvair engine turning a propeller.

The system is not cheap. Its suggested retail price is more than $2500. If you are building a Pietenpol and were planning on using a Stromberg, you’re probably not going to change plans and pick up one of these injectors. However let’s look at this from a different perspective. People who are spending $18,000-$20,000 to buy a Rotax 912 or a Jabaru 3300 will find that their engines are equipped with one or two Bing motorcycle carburetors. Although these carburetors are allegedly altitude compensating, in practice they are far from it. You can ask any operator of a Jabiru engine and they will tell you that at high power settings and high altitudes, their engines are very thirsty, and they have no way to compensate for this.  These expensive buy-it-a-box engines come with Bing carburetors because they are cheap. 

Now let’s look at the 3 L Corvair engine with the injector above. It is the most expensive Corvair powerplant I have built in the past couple of years; the price of the engine complete without the fuel injection on it is $11,500.  At $14,000, it is $4000-$6000 less expensive than imported engines fed by motorcycle carburetors. Combine this with the Corvair’s made in America pedigree, and its reputation as tough as nails, and many people find that it’s a choice they’re interested in. Corvairs are not for everybody. Most people don’t actually care where their products are made, or if they will be serviceable in five years. It’s a free world and those people can find engines that suit their needs. For people with different value systems, I am glad to conduct R&D to find out what is a real value in high-end engines.

Above, the engine runs on the stand in front of our hangar. The fuel line leads down to a rack of instrumentation, a high-pressure pump, and an external pressure regulator used for testing purposes. The engine ran very smoothly, and passed our early tests. I will have the unit on display and more information in our NO34 booth outside Building C at Sun N Fun all week.

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Schwartz Engine Runs at CC #22

Above at left with me is Blaine Schwartz of  Texas, a Zenith 750 builder who assembled his 2850 cc, Roy bearing equipped engine with Falcon heads at Corvair College #22. In this photo, we hold Blaine’s license plate displaying that he is a devout Chevrolet fan. 10 years ago, General Motors put up billboard advertisements with pictures of red Chevrolet Corvettes. The only caption they put on the bottom of the sign was big print that said “They don’t write songs about Volvos.” Building Corvairs is part of my lifelong admiration and passion for Detroit engines.

The above photo shows where Blaine started midmorning on Saturday. Roy shipped the case already assembled with his bearing on it with the crank and cam in it. This is how he delivers his product to builders. This is why at first glance it appears to be substantially more expensive than the parts to build a Weseman bearing engine. Blaine found it a good value and worth the wait to get a running start at his engine. This assembly from Roy is completely compatible with all of the products that we sell and directly works with Falcon heads.

 

In the above photo I am demonstrating to Blaine the use of my Snap-On electronic torque wrench on the rod bolts.

An overhead view showing the Pistons and Cylinders installed. Blaine’s engine is a 2850 cc powerplant, utilizing a Piston and Cylinder Set from us. The cylinders used in the Kit are Clark’s full fin heavy duty cylinders, bored .105” oversize.Clark’s does this boring for us on their very accurate machinery.

In the above photo, I use a soft rubber mallet to tap on Blaine’s Gold Prop Hub. Engines equipped with Roy’s fifth bearing use a Short Gold Prop Hub.

The above position, with the engine standing on its nose, is my preferred position in which to set the valves. This photo also gives a good view of the full fin heavy duty cylinders from Clark’s that are part of our 2850 cc Piston Kit. 

 

Above we are bolting on the Front Starter and giving it a good look before taking the engine outside to fire it up on the ramp.

30 hours later the engine is on the test stand ready for its run on Sunday afternoon. We utilized the engine to teach many people the assembly and priming sequence and how to install a Distributor.

Above, Blaine’s engine a few minutes into its test run. We did a full 30 minute break in on the engine with the RPM between 1800 and 2200. The engine ran flawlessly. Hats off to Blaine, John and Becky for running their engines at Corvair College #22.