Cherry Grove story, “The long way home”


In 2010, I took some time the week after Oshkosh to travel to Cherry Grove, Bernard Pietenpols home town in Minnesota. I went there with Mark Petz, our Corvair cylinder head expert from Madison WI. After getting back to Florida I wrote the story reprinted below. Since this has been a week of Pietenpol thoughts, I wanted to bring this back out for people who may not have seen it.

I consider BHP to be the Patron Saint of Homebuilding. I don’t say that lightly. Before him, it was just accepted that aviation was for rich people to do and working people to watch. The battle on this point didn’t end with BHP striking a blow for affordable aviation with his model A powered Aircamper. It still goes on today, and there are plenty of magazine editors, FBO operators and even people on the EAA board who think that if you work for a living your place is watching from the outside of the chain link fence. I am from NJ, and we have a three word phrase to express unwillingness to go along with someones idea for you. It is “F- – – That S – – -.”  I consider myself a foot soldier in the conflict to keep aviation affordable. BHP is my George Washington (Our first Commander-in-Chief.)

BHP was truly a genius. He knew how to repair Color televisions in the vacuum tube era of electronics, no small feat. The best lesson in life I ever learned from the man is that simplicity has made far more people happy than complexity. Many of the things I do, from live in a rural area, to not having a cell phone can be directly traced back to understanding that BHP knew a secret; The best things in life and flying are often the most simple in the most peaceful setting. It is hard to explain how much I respect the man’s legacy. Try this: I keep a Coffee can of soil that I picked up from the Cherry Grove runway in 2002 on top of my refrigerator. Once a year or so, when I am having a bad day, I take it down and stare into the soil in it and think about how the guy who walked on that ground knew how to live with peace of mind in a trying world. 


‘The Long Way Home’

After Oshkosh I took a few days to regroup at Mark’s shop. We decided to make a field trip out to see Piet builders Dave and Will Mensink, and make a trip over to Bernie Pietenpol’s home town, Cherry Grove, Minn. We made a couple of stops in Wisconsin, Minnesota and Iowa. Because our 450 mile loop was intended to go visit things that live in the past, it seemed appropriate to take Mark’s 1963 Corvair van.

H.L. Menken is one of my favorite writers. In the 1920s and ’30s, he and George Nathan would take long car trips in rural America without a time or destination, just a goal of “taking in the national mood.” Menken was one of the best known newspaper men of the day, a halfway point between Mark Twain and Walter Cronkite. Today, journalists think that news comes from NYC, DC or LA. Despite being nationally prominent and a lifelong lover of all things Baltimore, Menken knew that the story was “out there.” With this spirit in mind, Mark and I drove west to visit some places from long ago.

Mark displays his motorhead credentials. The pistons and rods are 350 Chevy. His 1963 Corvair van in the background is affectionately referred to as The Groovy Cruiser. It looks terrible but runs great.

Mark and I stopped to see this Stratofreighter on static display in the middle of Wisconsin. It had been flown into a tiny airstrip decades ago

Above is the cockpit of the Boeing C-97. It is powered by four 4,360 cid radials. A placard in front of the co-pilot lists the minimum weight, full flap stall speed as a stunningly low 69 knots. With their reversing propellers, these aircraft can land on short strips.

Third stop for The Groovy Cruiser was to visit the brothers Mensink and their Pietenpol project. Will, seated in the plane, is a worldwide cargo pilot for UPS. Dave runs a huge and successful family farm about 10 miles from Cherry Grove, Minn.

Above, an overhead shot of the Mensink Pietenpol during its weight and balance. Although a Piet is a very basic aircraft, it still is a good match for All of our Gold Components. Dave’s 2,700 cc engine has a Weseman 5th bearing, and was assembled by Mark at Falcon. It will be a potent, smooth performer on their aircraft.

Will Mensink’s hangar used to belong to Andrew Pietenpol, Bernie’s grandson. Inside this hangar is an exact full-size replica of Bernie’s Cherry Grove shop (his shop in Cherry Grove was in town, separate from the hangar). This door is the original from Bernie’s shop.

Bernie Pietenpol was a multi-faceted guy, and he did a lot of other things besides build airplanes and convert Corvairs. In his shop, he also repaired the most sophisticated piece of consumer electronics of his day: color televisions. This row of light switches is an exact replica of the ones in his original shop. They’re mounted overhead as you walk into the shop, and could all be thrown with one motion of the hand.

Will and Dave gave Mark and I a guided tour of Cherry Grove. I had been there only once before, with Grace eight years ago when Dave took the time out to show us this tiny hamlet. Years ago, it was very quiet, almost deserted. Today, there are a dozen or so people there. Bernie Pietenpol’s old airstrip is about a mile from town. Out in the fields, it would be impossible to find from the ground if you didn’t know where it was. In the above photo, Mark and I with The Groovy Cruiser at one end of the airstrip. It is private and still owned by the family. It looks a lot bigger in the photo than it is in reality. I would sincerely discourage anyone from flying there without first contacting the family.

Cherry Grove is the intersection of two streets. There might be two dozen buildings there. The above photo is Bernie Pietenpol’s old shop. I consider the location a very special place, perhaps the most sacred spot in the entire history of homebuilding as a passion for the working man. Being something of a historian and extremely passionate about this subject, I do consider taking two days out of my life and driving across the upper Midwest in a 46-year-old van as time well spent. However, I do want to caution people reading this that the shop no longer belongs to the family, and the owners are private people who are somewhat perplexed and not entertained by the concept that they own something that’s seen as a national treasure by others. Drive by if you wish, but don’t count on a friendly welcome. Cherry Grove has been around more than 100 years. Perhaps it’s just in a private era right now, and time will likely change this. Keep in mind that the spirit of Bernie Pietenpol and his ideals live more in the workshops of Piet builders around the world than a small shop in Minnesota. The ideals of George Washington are not restricted to the things that physically exist at Mount Vernon.

Fans of wooden aircraft will appreciate this detail. When we visited the shop in 2002, I noticed the awning frame out front, which had no roof on it at that time, was made from a Piper wing spar. You have to appreciate the values of a man who ended up with an apparently straight aluminum Piper spar and thought that its best use was an awning frame. If you look closely at the photo above, you can see the diagonal bolt holes where the lift strut used to be attached.

If you’re building a Pietenpol, take out the plans and look at the title block. When you see the name Hoopman, you will be looking at the same identity as noted in the quiet cemetery of Cherry Grove. If you look closely, you will see a Sky Scout engraved on the marker above. This is about 100 yards from Bernie Pietenpol’s shop. Yet the efforts of both these men do not reside in a shop or in a cemetery. Eighty-one years later, builders around the world enjoy the legacy left by these two men in their dogged pursuit of flying for every man.-ww

Pietenpol review in pictures, 15 more Corvair powered Piets


In addition to the four ships highlighted earlier in the week, here are a few more selected Corvair Powered Piets. I drew these photos from our regular website We have a lot of others, this is just a sample. There are a number of other well-known Corvair powered Pietenpols like Virl Deal’s 1,000 hour bird that I am saving for a second post. If you have a Corvair powered plane and have not sent us a photo in a while, please do, we would like to have it in a follow on album.

Above, P.F. Beck getting ready to take off. Photo Taken at Corvair College #12. PF was the host of Colleges 19,21 and 24. His aircraft has flow more than 200 passengers. It has electric start and a very quiet exhaust system. PF was awarded the Cherry Grove trophy in 2011 as ‘Corvair aviator of the year.’

Above, Shad and Gary Bell’s Piet in flight. Aircraft is based in Ohio. It has made a number of appearances at Brodhead. Gary and Shad came to CC#7 to get started on their engine. It is a modern 100 hp Corvair with electric start. The plane has a very nice finish on it, accomplished with industrial latex enamel. If you ever hear a fool say something like “latex paints make planes look like houses” ignore them. There have been Oshkosh grand champion aircraft painted with latex systems.

Above, Tom Brown’s pietenpol, flying since 1982.  Although it has spent its life in a cold climate, and it has competed with all the other beautiful aircraft that Tom owns and has access to, he has still managed to put nearly 1,500 hours on it. By my count, it is the highest time Corvair powered aircraft in the fleet. We did a weight and balance on this aircraft and it came in at a feathery light 624 pounds. This is 125 pounds lighter than one of the A-65 Continental hand prop aircraft at Brodhead. It is a very effective demonstration that it is a myth that Corvair engines are inherently heavy. Good aircraft building technique is far more important than which engine you choose when shooting for a lightweight plans built homebuilt. The engine is a BHP conversion without any modern updates, yet Tom has never put a wrench on the inside of it in the last 30 years.

Above, a photo of Kevin Purtee’s Pietenpol airborne. This plane flew 340 hours in a few short years before being heavily damaged in an accident in 2012. The rebuild is well underway. The engine ran with mild updates at CC#24, where Kevin and Shelley were awarded the Cherry Grove trophy for 2012.  Kevin credits his wife Shelley Tumino with much of his success. They hosted CC#22 in their home state of Texas. His engine is a modern electric start 100 hp and a Dan 5th bearing.


Above, Bob Lester of FL with his  aircraft. It was powered by a 65 hp Lycoming, now a 100 hp Corvair. This is a radically different aircraft than it was a few months ago. It when from barely having a positive rate of climb with two people on a hot day to being able to climb 800 feet per minute at the same load and conditions. It now has safe and smart-looking gear that works correctly. The Mount, spring gear and intake were built at our shop. The plane is 25 mph faster now on the top end. The engine is equipped with electric start and a Dan 5th Bearing. It was built at CC#17.

Above, Harold Johnson’s ‘Big Piet’ at Brodhead.This aircraft won Best Auto Engine Conversion at Sun ‘N Fun in 2010. The Big Piet builders completed and flew 5 of the 6 planes started, a record in group project success. Their first visit to our hangar was back in 2003.  The planes met with great reviews for both their operation and their attention to detail. They have 28″ wide steel tube fuselages. They all have modern 100 hp engines with electric start and MA-3 carbs.

Above, Frank Metcalfe’s plane at sun n fun the day before the tornado. This plane and her sister ships, the ‘big piets’, exhibit extraordinarily high craftsmanship. As many people know this aircraft was extensively damaged by the tornado. The plane is currently being rebuilt.

Above the plane of Bruce Laird who is also one of the big Piet builders from Carrollton. If you look closely you can see Frank’s airplane in the background. Like Frank’s, Bruce’s aircraft was extensively damaged. If these were factory built aircraft, they would have been considered totaled. But these aircraft are different. They represent years of hand work and care. They will not be written off as the majority of damaged aircraft at Lakeland were. The same hands that created these aircraft are  back at work, making them right again. I look forward to seeing these planes again in 2013.

Above is Gardiner Mason’s Pietenpol, photographed before it was damaged in the tornado. The plane is now repaired and flying again. The plane had made its public debut at CC#19.  Debugging his aircraft was the subject of an 18 page set of notes on cooling systems that we wrote. After working with us, the plane flew beautifully. After the tornado I spent some time with Gardiner at the show, and he was stoic about it. Everyone wanted to say they were sorry when they spoke with him and buy him a beer. It made me think about A.E.Houseman saying, “Ale does more that Milton can to justify God’s ways with man.” The plane has a 100hp Corvair with a Dan 5th Bearing and electric start. If you have an hour to learn, read the 18 page report here: On the internet there are a small number of critics that take every opportunity to say negative things about Corvairs and my work with them. Read the report and understand that while negative internet vermin type their bull, I am doing things like rebuilding Gardiners engine for free, running the Weight and Balance project and hosting Corvair Colleges. Take your pick on who benefits Pietenpol builders more. I don’t need to be thanked for doing things I want to, but I take a dim view of being criticized for it.

Above,Randy Bush of TN. at Brodhead with Miss Le’Bec (it is a combination of his girls’ names coined by his wife). His aircraft was seven years in the making. A consistent work of craftsmanship, the plane’s creation spanned both easy and hard years in Randy’s life. Many people new to homebuilding think that it is something you do if life is treating you great and you’re rolling in dough. Here is reality: The most successful builders I know understand that hours spent in your own shop, creating things with your own hands, is a vital part of a worthwhile life, and that this reality will be most evident at the hardest of times. Learning to make things is a crucial investment in your own sanity. Does it surprise anyone that really happy people always have a way of being creative? The plane has more than 400 hours on it. It has a 100 hp Corvair with electric start and a Roy 5th bearing.

Above, Kurt Shipman of Illinois with his Pietenpol at Brodhead 2009. His super clean installation features one of our Electric Start setups, Falcon heads and a standard rebuild straight out of our Conversion Manual. Kurt is a 39-year-old ATP who flys for the airlines.  A prolific ‘internet personality’ made the claim that Corvair Powered Piets all have ugly cowls. Kurts cowl housing his starter is so ugly that when he flew it to Oshkosh for the first time the plane won the Bronze Lindbergh trophy, as the 5th best homebuilt at Airventure. So much for critics.

 Above is a photo of Texan Hans van der Voort’s Corvair powered Air Camper at the Southwestern Regional EAA Fly In. His NX15KV won the Tony Bingelis Memorial Award for Best of Show there recently. Tony Bingelis was the greatest how-to writer homebuilding ever had, and Texas was his home turf. I’ve yet to see it in person, but everyone who has says Hans’ airplane is outstanding. How do planes with such ‘ugly cowls’ keep winning trophies? Hans’s plane utilizes a Zenith carb and one of out stainless exhaust systems.


Above, the Jim Ballew of OK, lands his Piet. It is a traditional BHP conversion. What is notable about Jim is that he also has a Corvair powered Davis DA-2 and a Corvair powered 601XL that he has built and flown. When a man has 3 Corvair powered planes you can be assured that there is a lot to like about the powerplant.

Above, BHP’s last original. This plane has 800 hours on it today, it lives at Brodhead and belongs to our friend Bill Knight. We did the weight and Ballance on this plane two years ago and overhauled the engine last year. On the outside it looks just like BHP made it, but inside it has a nitrided crank, Arp bolts forged pistons and one of our Black prop hubs and hybrid studs. Look closely and understand that BHP kept the thrust line low because he had the stock automotive blower fan on the engine, which sticks up higher than our electric starter set up.  BHP’s Corvair Thrust line was very near the location of the Ford’s thrust line. It was a familiar location, but if you look at most classic planes, the thrust line is closer to the top longeron. Note that the last original has the main axles far forward and it has die spring in a tube gear like we made for Bob lester’s Piet.

Above, the Pietenpol of Duane Duea of Minn., at right, (and Kurt Shipman’s at left). The photo was taken at Oshkosh 2009. Duane’s aircraft was completed in 1972 and is so true to Bernie’s plans that I initially mistook his aircraft for Bernie’s first Corvair-powered ship, which resides at Oshkosh in the Pioneer Airport. This aircraft has approximately 1,000 hours on the clock. We spent some time with Duane at our booth, where he reflected on the privilege of knowing Bernie Pietenpol in person. This aircraft is nicely complemented by Kurt’s, which was completed in 2008, 36 years later. Although Kurt’s aircraft retains a very classy, pure look, it takes advantage of all of our research and development.

If you’re a Piet builder or just a fan of Corvair powered planes, I hope you have enjoyed ‘Pietenpol week.’ We have a lot of shop work over the next 72 hours, but I am going to get in a mail sack update this weekend and also get an engine building series started for next week. Stay tuned-ww.

House Call on Pat Green’s 1,000 Hour Pietenpol


In keeping with the developing “Pietenpol Week” theme, today Vern and I drove about 2 hours to the northern edge of Florida to make a house call on a Corvair powered Pietenpol that has been flying since 1977. The plane is the handiwork and pride of a builder named Pat Green. Even though I have known him for 15 years and we live in the same state, Pat and I don’t often have a chance to get together.


Above, Pat’s Pietenpol. It has more than 1,000 hours on Corvair power. The installation has always been very close to BHP’s plans externally, but internally Pat went to forged pistons and an OT-10 cam more than 10 years ago. He was flying long before I started working with Corvairs, but he was never reluctant to adopt any improvement that my testing revealed. His original conversion manual from us was one of the first 50 I had printed, I have known him that long.

Many years ago he flew the plane to Corvair College #9, where he was much appreciated by Piet builders in attendance.  In the years since, we have been very busy and Pat was deeply involved in the hour by hour care of his late wife. After beating a few health issues of his own, Pat paid a visit to our hangar where he explained that his personal plan was to get back into flying full-time and really enjoy all the elements of it that he used to before greater responsiblity took priority. A key element of this was switching from a traditional Bernard Pietenpol hand prop/blower fan engine to one of our electric start systems. He had been hand starting the plane for 35 years, but being 77 and having had back problems, he thought going with key starting was a safety issue, and made the prospect of operating the plane solo a lot more appealing. From that point we made a plan for a house call and to get him a running start on a conversion to electronics doing the starting.


Above, a shot of the original BHP/blower fan conversion from an angle that illustrates why an engine set up this way doesn’t fit well with a high thrust line engine mount. engines with starters and J-3 eyebrow scoops can utilize a higher thrust line and still fit inside the shape of the fire wall. The Prop hub is an original BHP model. It is mounted by the original short flywheel bolt in very deep wells. I developed Hybrid studs 15 years ago to improve the mounting of the prop hub for engine with more output than traditional BHP conversions. A BHP hub can not be used with any of our starter set ups.

Pat actually traveled to Cherry Grove and spent time with the man himself. Pat stuck with the project and finished it after 10 years of on and off building. The plane was not the only aircraft in his life, there were many. But as he gets to the other end of his flying years, he is very clear that his Pietenpol is the centerpiece of his aviation life, and without question the best thing he ever did in planes. The Sport Pilot rule will allow Pat to fly the plane for many years to come, so it is inevitable that it will be the last plane in the stable of planes he has kept, but he says that all medical factors aside, if he were to have had only one plane, the Pietenpol would have made him the most happy. He will be very glad to finish out his flying hours in the plane, and he will log a lot more of them with a starter.


Above are the blower fan parts that came off the engine when putting the Front starter on. There are people who have suggested that this stuff weighs a ton, but it doesn’t the fan is magnesium ( we put a story up last year about burning them in a bonfire at one of our airport parties) and weighs less than a pound. All in all, an electric start system is going to add about 20 pounds to the airplane after you take into account things like the larger battery. It isn’t shown in the photos, but Pat is going with a John Deer style front alternator driven off the Gold hub.


Above is a look at the engine being test fitted with the starter and the gold hub. The parts, including the starter kit, a new hub, hybrid studs, the alternator , brackets, regulator and a belt cost Pat about $1,400. It is going to take a bit of time to re-configure the cowl and wire the electrical stuff, but overall, it isn’t a lot of money or time to get the plane set up to layout that is a much better match for Pat’s next few years of flying.

Below: Blast from the past, Pat and I stand with his Pietenpol at Corvair College #9, seven years ago. The caption in blue italics below is the original words from the 2006 College. note to fashion critics: I haven’t always had long gray hair, but I have always dressed like a refugee, even long before it was stylish.

“Above, I stand with Pat Green of Jacksonville, Fla. Pat started his plane in 1967, and first flew it in 1977. Since then he’s logged about a thousand hours in it. Again, the Golden Rule in action. In my hand I’m holding a photo of Pat and I standing in exactly the same positions in my old hangar eight years earlier. We had a laugh, because I pointed out Pat was wearing the same hat, and he commented that it looked like I was wearing the same shirt. Pat is good company, and a sharp observer of human behavior. When he talks, I listen because he’s a man of many experiences in life. Among them is having known Bernie Pietenpol personally.”

A few words about house calls and service to builders: The trip up to Hillard, a few hours of work and back took seven hours today. I charged Pat my standard rate for a house call: Zero dollars. If you get a look at the years of such house calls documented on our websites, keep in mind that I have never charged any builder, wether we were old friends or not, for a house call. Some have been fairly close like todays, many have been on the way to or from airshows, but there have been others that involved getting on an airliner to go help a builder solve an issue. All of this was done at no cost. Our business makes fair profit on the items we provide, but I don’t view every interaction with builders as a opertunity to generate revenue. That is how a corporation or a LLC might think, but not me.

There are plenty of things we do just because I am a home builder and I like builders. People who have yet to meet me often incorrectly assume that things like house calls are just for friends. In reality, the recipient has little to do with my motivation. I know a lot about homebuilts, and a great part of this was taught to me by experts, mostly gone now. Those men didn’t charge me for their time. My willingness to pay attention and take their message seriously was enough. I also suspect that they were paying back a previous generation of aviators also. I have many flaws as a person, but being an ingrate isn’t one of them.-ww