Waco Classic's New-Old World Biplane

The Waco Classic YMF-5D biplane brings back the good old days without all of the hassle

FLY0910_Waco8_1000

FLY0910_Waco8_1000

Waco Classic YMF-5DWaco Classics

WHAT IF YOU COULD bring back the magic of the golden age of aviation without the hassle of oil leaks, crummy brakes, no electrical system and short-lived fabric covering? Wouldn’t that be heaven for a pilot? Well, that’s exactly what Waco Classic Aircraft does. It builds brand-new sport biplanes right out of the 1930s but without the reliability and maintenance issues of 75 years ago.

In the mid-1930s, Waco was one of the most successful builders of personal and business airplanes in the country. Wacos were powerful, fast and a delight to fly, and they were expensive. That's why pilots coveted the graceful biplanes then, and now.
Waco — pronounced wah-co, not way-co like the city in central Texas — began life about 1920 as the Weaver Aircraft Co. After the relocations and management shuffles that were the norm for new airplane makers in that period, the company settled in Troy, Ohio. In the late 1920s, the company changed its name to Waco, probably as an acronym of Weaver Aircraft Co. Some say the name came from an airfield near Troy. Since Waco airplanes generate enough passion to support a museum in Troy dedicated to Waco airplanes, I am sure there are experts who are certain of the root of the name, but there is not necessarily agreement.

In the early years, Waco built dozens of models of biplanes, probably no two exactly alike. The company was among the first to offer a fully enclosed cabin biplane designed for purposeful transportation. By 1935 it created the YMF, what many pilots believe to be the most beautiful and desirable sport airplane ever built. That is the model that is back in production now by Waco Classic Aircraft.

The original Waco company devised an almost incomprehensible model identification system of letters and numbers. The first letter referred to the engine type, the second to the fuselage design and the third to the wings. At least I think that’s what they mean. To make it more complicated, numbers were tacked on after the letters to indicate the first year of production, or maybe some other model change.

The "Y" in YMF-5 stood for a Jacobs radial engine. Why Y instead of J? Who knows? The fuselage was an M and the wings F. There seems to be little consistency to the identification system, and the difference between models is often subtle.

Waco flourished through the Great Depression, or at least survived to create a steady stream of new models. As World War II loomed, the company supplied trainers for the military with many cadets flying the UPF-7 in basic training. Waco also built a large number of troop transport gliders.

The postwar boom in airplane demand that failed to materialize doomed dozens of airplane manufacturers, and Waco was one of them. By 1947, the company was out of business, and its type certificates and drawings went into the public domain.

In 1985, a small group of airplane enthusiasts in Michigan realized that the Waco type certificates were still valid if somebody wanted to put the airplanes back into production. The YMF-5 was the obvious choice because of its beauty and the huge number of Jacobs radial engines that are available to power the airplane.

It is an oversimplification to say that Waco Classic Aircraft simply set up shop and started building the YMF just like the original Waco had done 75 years ago. Though the type certificate is technically still valid, there are many changes that were necessary either because the same materials were no longer available or because superior materials and methods had been developed during the intervening decades. So returning the Waco to production required a series of STCs to the original TC.

One of the primary structural changes was replacing the mild steel tubing used to form the fuselage frame with high-strength 4130 steel. The steel tubing is now corrosion-proofed internally and epoxy-coated externally. The mechanical brakes were replaced by modern-design hydraulic toe brakes. A 28-volt electrical system was installed and the instrument panels were modified to accept full IFR instrumentation and avionics. Heaters were added to the forward and aft cockpits. The tailwheel was raised three inches and made steerable. A new stainless-steel firewall meets current burn-through standards. And on and on.

As complicated as it was to update the type certificate, the really big task for Waco Classic — or any airplane manufacturer for that matter — was to obtain a production certificate. An FAA production certificate authorizes a manufacturer to certify that each airplane it builds meets the standard of the type certificate. The requirements for control of materials, parts and procedures is daunting, but Waco Classic succeeded in meeting all of the FAA’s demands.

The Waco's wings are made of wood and are covered in Dacron fabric. I am sure the FAA had to reach back in its archives to find the standards for wood used in primary airframe structure, but it did. The wing spars are Sitka spruce, a wood prized by airplane builders for its long, straight grain and uniform strength. Waco Classic buys only "aircraft grade" Sitka but rejects a substantial portion of each delivery because it fails to meet the company's certified standard. Only the very best pieces of spruce are shaped into wing spars.

The wing ribs are the traditional wood truss structure with gussets, glue and staples used to fasten the components. Because it has a production certificate, each element of the rib, for example, has its own part number. The complete rib is tracked by number. The building process is much like an expert homebuilder would use to make an airplane, but the record keeping is the same as what Cessna or Beech uses. And every step in building a component, and then assembling the airplane, is signed off by inspectors.

The welded steel fuselage frame is surrounded by wood frames and stringers to give the fuselage its final form, though the loads are carried by the steel. The horizontal and vertical tail elements are braced by flying wires in the traditional way, and a jackscrew moves the leading edge of the horizontal up and down for pitch trim. There is a large, enclosed baggage compartment just aft of the rear cockpit with 100-pound capacity and a lockable hatch.

The upper wingspan is 30 feet, while the lower wingspan is 26 feet 10 inches. The lower wing was shorter in span on most models Waco built, and on some, particularly those with enclosed cabins, the lower wing was so small they were sometimes called sesquiplanes, with sesqui meaning 1½. The YMF is certainly not a sesquiplane, but the upper wing is enough longer that it’s easy to hit its tip on the hangar door while you’re looking at the lower wing for clearance.

The wood wings and steel airframe are amazingly strong. The Waco is approved for aerobatics with load limits of +5.2 Gs and -2.1 Gs at its maximum takeoff weight of 2,950 pounds. The day I visited Waco Classic's factory on the Battle Creek, Michigan, airport, a wing that taxied into a very solid object had been returned for repair. Just days before, the company had sent a set of repaired wings back to an owner in Africa who had flown his Waco between two trees. Nobody was hurt, and the wings were repairable.

The Waco Classic factory is unlike a conventional airplane factory because it is so quiet. A saw cutting through Sitka spruce or a craftsman hammering stainless steel to form an exhaust system are the soft sounds that replace the pounding of rivet guns in a normal factory. In many respects the factory looks like an airplane restoration center until you realize an entirely new airplane is taking shape from stacks of wood and steel tubing.

Production moves at an uneven pace because no Waco is completed until it is sold. Work begins on the basic airframe because that does not change; assembly and finishing are not commenced until the airplane has an owner. The list of ways the owner of a new Waco can customize it to his liking is almost endless. And the list of colors and paint schemes available truly is endless.
The Jacobs R775 seven-cylinder radial engine on the original YMF was rated at 225 hp. When Waco Classic put the airplane back in production, power output was upped to 245 hp. Now you can select either 300 or 275 hp engine ratings. The engine can be fuel-injected as an option, but a carburetor is standard and works really well on the radial engine design.

By the time the YMF was originally designed in the 1930s, the NACA had perfected what was then called the pressure cowling. In the early years of air-cooled engines it was believed that putting the cylinders out in the breeze was the most effective way to remove heat. But wind tunnel research by the NACA demonstrated that a tight-fitting cowling that would pressurize the ram air entering the cowling, and force that air over the cylinder heads, provided superior cooling. The cowling on the Waco is a true classic design, with its diameter matching that of the forward fuselage — and the bumps to accommodate the valve rocker arm covers.

There are three different propellers available for the Waco Classic, though not all are approved on every engine power rating. The newest offering is a wood MT propeller that has a modern airfoil and generates a great deal more thrust for improved takeoff and climb. A Hamilton-Standard metal constant-speed prop is also available, though it adds considerable weight without adding much in the way of performance.

The Waco is approved for IFR, as well as day and night VFR flight, and the company has gotten a lot of attention by offering the Garmin G500 flat-glass system as an option. I have the slightly more advanced version, the G600, in my Baron and love the enormous capability it provides. But I would never want the system in a Waco. Flying a Waco is all about looking out and enjoying the view, not studying the instrument panel. When riding around in a Waco, about the only things I’m going to take a quick look inside for are airspeed and altitude, and you can’t beat a big round gauge to show that information.

I would, however, want the optional Garmin GTS 800 traffic system, because midairs are always a threat and that traffic system calls traffic by clock position, high or low, verbally into your headset so you don't need to look inside.

The only large open-cockpit biplane I had ever flown was a Stearman, so I didn’t know what to expect from the Waco. Let me tell you, the Stearman is a fine airplane and proved itself to be an excellent trainer, but there is no comparison between the Waco, designed for flying sportsmen, and the Kaydet, designed for the Army Air Forces. The Waco’s flying qualities match its elegant appearance in every way.

In the Waco, you can adjust your seat up or down, which is very unusual in open-cockpit biplanes but gives any pilot the optimum position to see over the nose and still be protected from the slipstream. The windshields, which have been redesigned from the original, are very effective, and there is no buffeting in the cockpit. And as you can imagine with a factory in Battle Creek, the Waco pilots have to fly in cold weather, which they find to be quite comfortable down to 30 degrees or so, thanks to the effective heaters and good wind protection.

The Waco is a taildragger — a tame one — but still demands proper footwork on the pedals so that the airplane is aligned with the runway centerline on touchdown. Tailwheel steering is effective on the ground, and visibility isn’t bad looking down the sides of the fuselage, but mild S-turning is required to see what lies directly ahead under the big round engine. Pilot training is included in the purchase of a Waco Classic.

The Waco has four ailerons, while many biplanes of the era had ailerons on only one of the wings. The four ailerons are effective and control forces are reasonable, but roll rates are more typical of a conventional airplane than one designed expressly for aerobatics, which the Waco is not. Pitch stability is extremely positive, and you will find yourself cranking in trim for every change in airspeed.

Waco airspeeds for takeoff, cruise and landing are not much different than they are in a Skyhawk. But there is a big difference in drag. Forcing air between two wings, and over exposed flying wires and struts, creates an enormous amount of drag, so the Waco simply will not accelerate much beyond normal cruise no matter how much power you use or how far you stuff the nose down.

Fuel is carried in two tanks in the center of the upper wing with 48 gallons as standard. Two more tanks can be added to increase capacity to 72 gallons, and most Waco owners opt for the long-range tanks. The Jacobs burns about 15 gallons an hour in normal operations, not really much different from a Continental or Lycoming of similar power.

Of course flying the Waco is wonderful, but the fun doesn’t end when you land because, wherever you go, you and your airplane will be the star. Waco owners quickly get used to the line crew waving them into the spot just outside the door, where everyone can get a good look, and believe me, they will look and want to chat. Waco owners will never be lonely on any ramp.