Melby Cavalier 1.5
This is the story of N3143D -
A homebuilt airplane called a Cavalier.
The Cavalier is a wood and fabric two-seat homebuilt airplane designed in Canada by Stan Mcleod based on the French GY-20 Minicab (designed by Yves Gardan in 1949).
For more information on the Cavalier, check out:
https://sites.google.com/site/cavalieraircraft/model-history
https://en.wikipedia.org/wiki/MacFam_Cavalier
N3143D was originally buit by David Melby of Minnesota. David completed N3143D in 1982. An article on David's Cavalier was published in EAA's Sport Aviation January 1984:
The Melby Cavalier 1.0:
SADownload-5.pdfDavid did a beautiful job on his first Cavalier - lets call it the Melby Cavalier 1.0.
Built between 1975 and 1982, David’s N4341D was flying 1982, and eventually removed from flight in 1993.
N4341D was originally fabric covered as per plans. However, David became quite involved in a new Cavalier redesign effort called the Celerity (http://mirage-aircraft.net/info.html). The Celerity embraced smooth lines possible with composite construction.
Inspired by his experience with the composite covered Celerity, David decided to recover his Cavalier with foam and fiberglass composite.
In the composite redo, he removed tip tanks and installed 17.5 gallon d-cell wing tanks (between spar and forward leading edge), and installed a rear sliding canopy. I have been calling this redo of N4341D the Melby 1.5 Cavalier (the Melby 1 being the original fabric covered incarnation of this very airplane).
Unfortunately, time caught up with David before he could finish the composite rebuild of his Cavalier. David lost his FAA medical, so could no longer legally fly his Cavalier. I bought his project (I call it the Melby 1.5) and am working to get it flying again.
With no medical certificate, David began construction of an entirely new Cavalier, but this time with the goal of making it as light as possible in order to conform to Light Sport Aircraft requirements. Light Sport Aircraft do not require a medical certificate to fly. The following site chronicles David's build of the Light Sport Melby Cavalier 2.0:
(https://sites.google.com/site/cavalieraircraft/individual-aircraft-pages/david-melby-site)
After I bought the Melby 1.5, David decided to sell his LSA attempt Cavalier (the Melby 2.0). Sadly - I had to many projects going on to purchase that beauty too, but I just came across YouTube videos by the new owner (Jonny Sprague) of Melby 2.0:
https://www.youtube.com/user/Jonny20thebombdigity
Congratulations Jonny! That is a beautiful Cavalier!!!
Melby Cavalier 2.0:
A unique 100hp O-200 LSA Cavalier
A Wide World of Cavaliers
The Cavalier is a plans built airplane, meaning that the builder gets nothing more than a set of drawings. Armed with little more than basic dimensions, the builder heads off to a lumber yard, and if he works hard and he's lucky (and builds as slowly as me), 20 years later has something that approximates the airplane design.
As you might imagine, over the years, builders usually get all sorts of "ideas" about what they would like to do differently. Thus, plans built airplanes tend to be remarkably "diverse" in their embodyment - much more diverse than the now common pre-fab kits such as the Vans RV's. Here are a few pictures of "Cavaliers":
Weird History
How did I become interested in the Cavalier? I first fell in love with another beautiful wood airplane called the Osprey 2. Starting it in 1980, I finally finished the Osprey in 2000-2001. I flew it all over the continent including up to Arlington WA, through Canada to a few times to visit family, and out to Oshkosh twice. However, by the time I had finished the plane, I had a small family and the Osprey just wasn't the right airplane. If you want to know more about my Osprey check out its website: sites.google.com/view/hughes-osprey/home
Here are a few pictures of my Osprey 2:
While thinking of what my next airplane should be I had seen a Cavalier built with a "jump" seat, making it a 3 seater (maybe 2+1 seater). I liked the Cavalier's design, I might just about be able to afford it, and to seal the deal its from Canada. So I started in on a Cavalier.
I didn't finish before I realized I needed something even bigger (strangely, small kids get bigger:-). So my Cavalier went to the back of the hanger, hopefully to be finished later. Here's how she sits now:
Marty Maisel's Cavalier
During my Cavalier build, I could turn to Marty Maisel for advice. Marty is a brilliant engineer and master craftsman. Marty lives only a few miles away form me, and his Cavalier is based out of Lincoln CA. Marty was a NASA engineer working on the propellers of the Osprey VTOL and his work on his Cavalier is beautiful.
In a fun coincidence, Marty was working as an engineer at NASA Aimes Research Center at the same time I was there in 1981. I was just a high school brat dating the boss's daughter and working on the initial Computational Fluid Dynamics models for hypersonic airflow.
For more about Marty, see:
http://eaa1541.org/members/newsletters/february-2016/builders-corner/
http://eaa1541.org/members/newsletters/march-2016/members-spotlight-marty-maisel/
Take a look at Marty's beautiful Cavalier. Not only a fantastic engineer, Marty is a true craftsman doing some of the best wood construction I have ever seen:
Maisel's Slotted Semi-Fowler Flaps!
Besides the beautiful woodwork the underlies Marty's Cavalier, Marty has engineered and built Fowler Flaps into his Cavalier. Most Cavaliers have simple spilt flaps.
Wing flaps serve a number of purposes. They increase effective angle of attack of the wing relative to the fuselage - making it easier to see the landing strip on approach. Incidentally (pun intended), flaps increase the effective angle of attack of the wing without increasing the angle of attack of the ailerons. This increases the safety of slow speed flight by increasing roll control during slow flight.
Finally, flaps can also increase total lift. Simple and Split Flaps increase lift by increasing effective wing camber. Wing camber is defined as the convexity of the curve of an aerofoil from the leading edge to the trailing edge.
Fowler Flaps increase total lift by not only increasing wing camber, but also by increasing wing area. Fowler flaps slide out and down from the wing. As they slide out, wing area is increased. As they slide down, wing camber is increased.
While Split flaps will decrease a Cavalier's stall speed ~5-8%, Marty's flaps should decrease stall speed ~10-15%!
See this page for more discussion on Marty's Cavalier Flaps.
Marty's absolutely beautiful Cavalier is for Sale!
Sadly, age has caught up with Marty and his Cavalier is for sale. His son Scott is asking$25,000. From the add: "Brand new airplane, Cavalier with Airworthiness certificate. $25,000 or best offer." To clarify, the plane has its' Airworthiness Certificate - but has only started on the 40 hour test phase. Here are the pictures from the ad:
But back to the Melby 1.5!
When I’d heard David Melby was selling his first Cavalier, I mentioned it to airport buddies of mine. My airport buddies had been goading me to finish my Cavalier, so I deflected with tales of David's Cavalier. It was well built, beautiful, and very interesting in its conversion to composite. I proposed that I’ll would contribute an engine if they’d go buy David’s airframe - and thus a new partnership was born to get the Melby Cavalier 1.5 flying again.
Our first job was to bring the Melby 1.5 to its new home at the Davis/Woodland Airport (KDWA). Cecil and Ann McLemore set off with a trailer, and a week later returned with our new project:
Fuel Tanks
Our first job after unloading our beautiful Melby 1.5 into its new hanger, was to figure out what to do with about the fuel tanks. David did a beautiful job of building 17.5 gallon composite fuel tanks into each newly composite recovered wing. However, in the early 1990's it was not well recognized that epoxy/fiberglass tanks do not stand up well to avgas. Worse, additives and ethanol in automotive fuel quickly disolve epoxy/fiberglass tanks. We were faced with the options of either coating/sloshing the tanks with a fuew resistant sealer, or cutting the tanks out and replacing them with aluminium tanks. We decided to go with a sealer since 1) the tanks were new. Having never seen fuel, the coating should adhere well and provide a long lasting fuel resistant seal. 2) We are lazy and really want to see this beautiful bird flying soon. Cutting up the beautiful wings to install aluminum fuel tanks may be the right thng to do in the long run, but was too disheartening to do now. We built a large round wing cradle that we could roll and tip, effectivly sloshing all surfaces within each wing tank. The sloshing/sealing compound was poured into each tank, rolled and sloshed about, and then drained. We did this twice for each tank:
Mounting Fuselage onto the Wing
The next step was to mount/mate the fuslage and wings. To do this, we lifted the fuselage up into the rafters of the hanger, then carefully lowered it back down on to the wing. The Cavalier is built with a one piece wing. The center section of the wing fits into a slot/cradel in the fuslage.
A "New" Engine
After mating wings to fuselage, the next step was to mount an engine. N4341D was originally powered by a Lycoming O-320, but the engine was replaced with a Lycoming O-290 after an early off field landing. I happened to have a 160hp Lycoming O-320 B2A, which should fit perfectly to the motor mount, and would make a great engine for the Cavalier.
Fun "Small World" Side Note: N3143D's original O-320 failed in flight in 1985 and was replaced with an O-290. In 1993 David decided to do a composite recover of N3143D, but never finished. When David gave up on the composite rebuild of N3143D, he decided to sell the Lycoming O-290 engine to Marty Maisel! Twelve years later, airframe and O-290 engine are now back within 20 miles of each other!
The O-320 engine I am planning to install only has 280 hours on it, but it has been sitting for 10 years. While the engine had been pickled (filled with oil, sealed, and had dehydrator plugs installed), I still wanted to go though it to check for corrosion. Using a bore scope, we poked into every hole I could easily open (accessories, oil pan, cylinders, and under cylinders). Lucklily, no significant corrosion! Some gunk, but in general pretty great condition. So its was time to replace all the hoses, rubber, and gaskets. Additionally, I installed a full flow oil filter.
Decoding the name of the engine: Lycoming O-320B2A
Lycoming (Manufacturer)
O (Normally aspirated - meaning carburator rather than fuel injected and with out turbo or supercharger)
320 (320 cubic inch displacement)
B2A (version number with 160 hp (119 kW) at 2700 rpm, Minimum fuel grade 100/130 or 91/96 avgas, compression ratio 8.50:1)
My O-320B2A engine:
Mounting the Engine
Fortunately, the O-320B2A engine I inteded to mount has the old style "conical" mount case, which should fit without any modification on the engine mount that is already on the airplane. After removing some of the Osprey specific hardware (exhaust, oil cooler, baffels) and installing a oil filter we hung the engine on the airplane's motor mounts:
Engine Baffles
In order cool an air cooled engine, baffels or air dams are used to efficiently direct as much of the air entering the enging cowl over only the engine rather than escaping around the sides. Tony Bingelis published a generic set of Lycoming engine baffel templates in his On Engines book. I think you can also find them in a back issue of Sport Aviation or here: https://www.eaa.org/eaa/aircraft-building/building-your-aircraft/while-youre-building/building-articles/engines-and-firewalls/baffling-your-lycoming-part-1.
Tony's templates were over a grid that at full scale were to be 1" squares. He recommened freehanding new full scale templates on a 1" grid - something far beyond my skill. However, I did find that at Kinkos/FedEx the template illustration could be copied to a 11x17" sheet at 200% zoom (cost 27cents), and then at 366% zoom on a blue print printer to exactly full scale on a 3'x5'sheet of paper ($12).
Sliding Canopy
David Melby made a beautiful sliding canopy - much like the sliding canopies seen on many RV aircraft. Here are a few pictures: