Pitts Special

Sixty years ago, its vertical ability redefined aerobatics—the marque is alive, we'll and rewarding skillful pilots.

Until the advent of the Pitts Special, aerobatics was a horizontal affair, even in the hairy-chested, fuel-sucking, 450-HP Boeings and Wacos. Practitioners pirouetted under the stern God of Energy Management—gravity and drag meant vertical maneuvers were brief events.

A small, clean biplane taking advantage of progressively more powerful, and lighter, opposed engines being developed took akro through the roof.

First flown in 1944 (or 1945—sources vary) as a single-seat homebuilt with only a 55-HP engine, the type has developed into today’s highly refined and FAA-certified, two-seat, 300-HP aerial hot rod used for advanced training and—at least in lower categories—competitive aerobatics. Many different variants have evolved over the years, including factory-built and experimental versions, but there remain two main types: a single-seater and a two-holer. Today, you can buy a new, factory-built machine from certificate holder Aviat Aircraft, or get the plans and components for a single-seat version (S1-C or S1-SS) from Steen Aero Lab (www.steenaero.com).
Dominant in aerobatic competition during the 1960s and 1970s, the Pitts Special eventually ceded that position to more modern monoplane designs from Extra and Sukhoi. Even Pitts himself saw the monoplane light: Before his death in 2005 at age 89, he designed but never built the Model 13, an enclosed coupe. But the basic biplane design of the Special remains popular as a recreational and training aircraft, and still can be seen strutting its stuff at airshows, fly-ins, pancake breakfasts and in private hangars throughout the world.

It’s not for every pilot, of course. Its small stature, dictated by the need to keep things light and strong, means a short fuselage and stubby, relatively highly loaded wings when compared to most other personal airplanes. All of this results in an airplane responsive to the slightest control input, whether on or off a runway. If you’re looking for a one- or two-seat cruiser, look elsewhere. On the other hand, if you’re looking for an airborne toy, something to both challenge and perfect your skills, you’ve come to the right place.

History
The S-1 (single-seat) and S-2 (tandem seating for two) Pitts Special is the brainchild of Curtis Pitts, a designer and cropduster, who envisioned the airplane as the first specifically designed for aerobatics, according to the International Council of Air Shows Foundation. From the start, Pitts focused on keeping his creation small and light, something distinctly at odds with the much larger, radial-engined biplanes then popular. By keeping things smaller than the norm, Pitts could incorporate a relatively underpowered flat engine and still obtain excellent performance.

Despite the Special’s enduring popularity, Pitts also designed several monoplane types. But the biplane design—affording double the aileron capability in most variants—offered the greatest strength and lift in a smaller package.

Early Championships
The first Pitts Special to achieve notoriety was L’il Stinker, flown by aerobatics legend Betty Skelton, to three consecutive U.S. Female Aerobatic Championships, in 1948, 1949 and 1950. At the time, all Pitts Specials were built by Pitts. It wasn’t until 1960 that plans were offered.

The first Pitts Special one could build in a garage or hangar was the S-1C, characteristics of which included a flat-bottom wing, bungee-cord landing gear, two ailerons and a single seat. It was powered by pretty much anything its builder wanted to hang on the front, from 85-HP Continentals to 200-HP Lycomings. According to Steen Aero Lab, which also markets S-1 plans and components, the S-1C is the “benchmark” version. “
“Nearly all homebuilt S-1s used S-1C plans for the fuselage and tail, with supplemental wing plan options,” according to the company.

Soon, variants began coming out of Pitts’ shop, with differences mainly resulting from tinkering with horsepower, fixed or constant-speed props, and flat-bottom or symmetrical wings. Homebuilders also incorporated their own changes, resulting in a wide range of versions—and disagreements between aficionados as to which is which.

These include the S-1D (S-1C with a slightly stretched fuselage and four ailerons), S-1E (a homebuilt), the S-1S (commonly known as the “roundwing” Pitts, it was certified in 1973 and features symmetrical airfoils, four ailerons and a different upper-wing design enabling it to stall first) and the follow-on S-1SS.

Follow-On Designs
One result of Pitts’ refusal to leave we’ll enough alone was the S-1-11B, or Model 11, also known as the Super Stinker. Still a single-seater, it featured a 300-plus-HP Lycoming, four ailerons and a symmetrical airfoil (better for inverted flight than the flat-bottom version), and was available as either a factory-, plans- or kit-built airplane.
The S-1T, a certificated, production version of the S1-S replaced the S-1S in 1981, according to Steen Aero Lab. It came with a 200-HP Lycoming, constant-speed prop and redesigned ailerons. However, there is an S-1T with a 180-HP Lycoming currently available in plans or production form from Aviat, according to its website, www.aviataircraft.com.

There was even an “Ultimate” version, with full-width ailerons.

Two-Seat Model
Meanwhile, a two-seat model was developed. It sported four ailerons and a symmetrical airfoil. The prototype S-2 had a 180-HP engine; production airplanes, designated S-2A, came with 200 ponies. Soon, the S-2B came on the scene, with 260 HP and featuring improved ailerons and rudder. It was followed by the current production model, the S-2C, tweaked by Aviat VP of Engineering and longtime aerobatic pilot, Ed Saurenmann to make inside and outside aerobatic handling more symmetrical, increase cruise speed and improve handling on landing.

Of all the models and variants developed over the years, many remain available. For example, Aviat Aircraft’s website shows that it currently offers plans for the S-1S, S-1T and S-1-11B. The S-2C is in production and it will build the S-1S and S-1T on demand. Aviat also provides parts support for versions no longer in production.
Despite the S-1/S-2’s popularity, additional Pitts versions were developed. The Model 12, the last design built and flown by Curtis Pitts, was a slightly larger two-seat biplane specifically designed to use the Russian Vedeneyev M14P/PF radial engine of 360-400 HP. Plans are available from the current owner of the rights to the airplane, Jim Kimball Enterprises (www.jimkimballenterprises.com).

Finally, Steen Aero Lab has been developing the Pitts Model 14 for some years. It was one of Curtis Pitts’ last designs and is billed by Steen Aero Lab as “a leading-edge two-place aerobatic biplane.” Like the Model 12, it’s designed around the 400-HP Vendenyev M14PF nine-cylinder radial.

Handling
A Pitts is about as small as a biplane can be and still carry two people, fuel and a large engine. Some owners, however, point out that filling both seats creates weight-and-balance problems, especially if you intend aerobatics. And who wouldn’t?

Both basic models are exceedingly clean and, to put it mildly, go like crazy. It’s hard to believe that a few years ago these were considered at or near the top in world competition, but are now being used for primary training for those moving up.

The controls are we’ll harmonized. For one who came up in acro flying an Aerobat or Citabria, the overwhelming feeling is it’s only necessary to think about a maneuver to fly it. Most of those pilots badly overcontrol a Pitts the first time out. For one accustomed to running out of speed in the vertical almost instantaneously in a Citabria, the Pitts is a revelation.

But for all the delights it brings once airborne, visibility on landing is awful and the airplane is just plain hard to land compared to a Citabria or Extra. We’ve seen too many NTSB statements for Pitts landing accidents that bluntly say that the probable cause was, “The failure of the pilot to maintain directional control during the landing rollout.”

Of course, this should surprise no one: Take a look at the short fuselage, small tailwheel and relatively narrow main gear. Then decide how you’ll see the runway in front of the airplane when it’s in the three-point position. It’s essential to get a good checkout before you fly the airplane home, or you run a significant risk of tearing it up on your first couple of landings. It’s also essential to leave at home any tricycle-gear habits and remember to perform S-turns while taxiing.

Anyone moving up to a Pitts also should become proficient in performing forward slips because it is an effective method of keeping the runway clearly in sight on final approach. And, although the S-2C’s published “clean” VS1 stall speed is a seemingly benign 56 knots, it’s a few knots higher than the VS0 “dirty” stall speed of high-performance singles such as the Bonanza and Cessna Centurion.

Is the Pitts a handful? Those who have fallen in love with it emphatically say, “No!” Pitts guru Budd Davisson, for one, says he can teach anyone to land a Pitts. “The Pitts Special’s reputation for being a handful on the ground is grossly exaggerated,” he adds. Davisson offers a transition course for aspiring Pitts pilots, estimating around 8-10 hours stick time for someone with a tailwheel endorsement, but admits the time required can “vary all over the block and is impossible to predict”.

Maintenance/Inspection
With fixed conventional landing gear and few avionics or instruments, a typical Pitts Special is about as simple as airplanes get. The airframes are fabric-covered steel tubing, with a plywood torque box joining the wing spars.

In addition to the standard aerobatic airplane pre-purchase checklist, look for slop in the control system. It often just requires an adjustment but bearings can be worn out. Any Pitts flown regularly for aerobatics should be inspected frequently. Make sure the inspection holes have been cut in the underside of the wings, indicating someone is looking at the structure.

Once the wings are bolted together, the upper and lower wings form a rigid unit, so an impact to the lower wing may result in damage to the upper. It’s essential to inspect each wing. Look to see if the spinner and nose bowl line up. If not, the bushings on the engine mounts are worn and are allowing the engine to sag. While this is initially cosmetic, it can result in the alternator being pushed into the nose bowl and the exhaust hitting the front of the firewall as we’ll as crushing the air box.

According to Budd Davisson, “There’s an easy way to tell if a Pitts has been subjected to extremely hard aerobatics outside of its design envelope. The most highly stressed part of the airplane is the anti-drag wire inside the top wing in the first bay outboard of the center section. The back ends of those wires go through the rear spar and come out inside the fabric area either side of the handhold behind the rear spar. If the airplane has been flown too hard, chances are there will be damage where the wire’s nut sits on top of the block that’s glued to the rear face of the rear spar (just inboard of the root rib).”

The engine and prop might demand some extra inspection time, especially if your mechanic isn’t familiar with an aerobatic engine installation. Many Pitts may come with a smoke generator, another oddity for the average mechanic.

Of course, the covering on any fabric airplane should be considered suspect, especially if the example hasn’t been hangared. Any ownership budget should set aside some dollars to recover the airplane at the appropriate time.

Finally, and while we’re not aware of any systemic corrosion issues with the steel tubing in a Pitts, the prudent purchaser is always on the lookout for related issues.

Pricing/Modifications
The Aircraft Bluebook Digest doesn’t track the Pitts Special, so we searched the old standby, Trade-A-Plane, as we’ll as some aircraft sales websites. We were surprised at how few Pitts were on the market. We did see an S-2B with a total time of 655 hours and five hours since major overhaul for an asking price of $89,900. A major overhaul at only 655 hours total time didn’t give us any warm fuzzies—we couldn’t help but wonder if there is an associated damage history of at least a prop strike.

We saw a 2005 S-2C with 511 hours total time, smoke system and a Garmin 250XL advertised for $198,500. Various versions of the S-1 had asking prices from $18,500 to $31,500.

As a pure sport airplane, Pitts modifications are usually designed to improve some aspect of the type’s handling or maintenance. Items like clear, Lexan floor panels, smoke generators, Haigh locking tailwheels (admired by new Pitts pilots, less so by old sticks) and spring steel gear (to replace the older bungee-cord design) are popular mods. Other add-ons or replacements, depending on the aircraft’s age, include inverted fuel and oil, electrical systems, Ceconite fabric coverings, seat-bottom parachutes and new, five-point harnesses.

Type Clubs/Support
We’re not aware of a type club devoted to the Pitts Special, unless you count the various national and international organizations devoted to aerobatics. While not type clubs per se, they are populated with pilots who have flown—and may still fly—the Pitts and have a thing or two to share. We do recommend joining the International Aerobatic Club for information and support on Pitts—its members were extremely helpful in providing information for this article. The local Experimental Aircraft Association chapter may be another great resource, especially for a kit- or plans-built example.

The ultimate aficionado, however, is the aforementioned Budd Davisson, whose Web site (www.airbum.com) includes substantial resources for the pilot merely wanting to learn more about Mr. Pitts’ Specials or needing detailed information on which one to choose and how to fly it.

Owner Comments
I have loved the Pitts for a long time. Once the S-2A came off the assembly line in the early 1970s, it became my airplane of choice for airshows and giving aerobatic instruction. I flew several thousand hours of solo and formation aerobatics in the S-2A. It is still my favorite formation aerobatic airplane—maneuverable, solid and dependable. There are lots of wires and struts on it that you can use as sighting references for precision aerobatics.

The Pitts retains the unequaled romance of flying a biplane and it looks like a bundle of energy when it performs aerobatics. However, it is just hard enough to land we’ll that it keep you on your toes and out of your ego. You cannot grease it on unless you pay total attention on every landing.

The deep fuselage makes it uniquely stable in knife-edge formation and, therefore, in formation slow rolls.
The same deep fuselage creates landing and flight visibility challenges. If you sit too low in your seat, the sides of the fuselage block your peripheral and downward vision. I solved this by using carpet samples for seat cushions. They resisted compression under Gs, so my seating position and sight picture remained steady. When they got a bit worn down, I could just add one more piece of carpet and raise myself up in fractions of inches, which is how you fine tune your position above the cockpit side and below the canopy.

Early on, the practice was to make tight, curving approaches to land, rolling out in the flare. That proved to be a problem should there be any traffic where you had to extend your downwind—so you had to fly level on final for some distance. That doesn’t work because the whole airport disappears. There were a number of accidents where a Pitts hit a vehicle or an airplane that had pulled onto the runway and the Pitts pilot simply couldn’t see it.

The problem was solved by flying final in a forward slip, with power as needed. That allows you to easily see the entire runway. The airplane is so maneuverable that it can be held in the slip until we’ll into the flare, when it is straightened out and both sides of the runway can easily be seen in your peripheral vision.

If you consider buying one, make sure you have plenty of tailwheel flying time and access to a highly experienced Pitts instructor who can coach you on the fine points.

Debbie Gary
Via email

I’ve owned and flown several single-seat Pitts Specials and have flown four different S-2As. The handling characteristics are quite similar. There are a bewildering variety of configurations and modifications, so before buying, decide on the mission for the airplane, competition, recreation or instruction and whether transportation is going to play a role.

A Pitts is not for pilots with clumsy feet or who don’t have the time or money to fly at least once a week. Most have been through a lot of aerobatics, so a pre-purchase exam by a mechanic who knows them we’ll is needed.

The airplane needs to be hangared to protect it from the elements. It’s normal for the whiskey compass not to work very well. With two aboard, an S-2A will not be able to do modern advanced and unlimited aerobatic sequences.

The most useful information one can get is in excerpts from the IAC’s Sport Aerobatics magazine. I think there are three or four volumes of technical tips reprints from the magazine—they have valuable information on fixing various problems pilots have encountered with Pitts Specials. I highly recommend joining the EAA and IAC and flying and

Talking with Other Aerobatic Pilots
Never, ever be embarrassed about having to make a go around in a Pitts. When I get into a new one, I generally ask for the option, rather than a full stop, during my first 100 landings. It reduces the stress level.
The control cables run under the seat, so on your preflight, make sure there’s nothing under there to jam them. Anything you drop in the airplane can come back to haunt you.

Gopal Ramachandran
Via email

My first aircraft was a Pitts S-2B. Having flown dozens of airplanes, including the Stearman, Citabria, Decathlon, Extra, Sukhoi, T-6 and several WW II fighters in aerobatic flight and competing through Unlimited in both Pitts and Sukhoi, as we’ll as flying 10 years of airshows, I believe the Pitts series of aircraft is the only one that prepares a pilot for all of the others.

The Pitts will teach you faster and make you a more competent pilot for any type of flying you do than any other aircraft.

Simple, rugged construction gives a low operating cost if the operating limits are respected. The dirty little Pitts secret is that a two-seat Pitts is over gross and aft CG with two 180- pound pilots, no matter what the fuel loading. Go to any popular aerobatic flight school and you will see two big pilots, each with 15-pound parachutes, get in a Pitts S-2B with full fuel and go do inverted spins. A 400-pound useful aerobatic load does not go far. Thankfully, a Pitts seems to tolerate any size person that fits inside, albeit with some mushiness in control response.

That caused me to look at an Extra 300L, with its greater than 600-pound useful load, and the Sukhoi 29, with its 950-pound useful load, to be legal with two people aboard.

Flying an S-1T in the Unlimited category, I had to use all the +6 and -4.67 G limits and 203 MPH Vne. I did it many times a flight for hundreds of practice flights with no visible wear on the airframe. The key to longevity for a Pitts is to never snap roll at over 140 MPH.

If you fly frequently and want an economical aerobat that will take you up through learning Unlimited aerobatics, an S-2B with a three-blade MT prop has proven to be the best bang for the buck. Two cautions: Canopies are fragile. The chap who bought my S-2B blew the canopy off on his first flight. Secondly, complete spin training is a requirement—a Pitts is designed to recover almost instantly from any spin, but will also enter a spin quickly when a ham-footed pilot tries to skid around a slow base turn to final.

If you want a low-time S-2B without damage history, be ready to pounce on the first one you find (there’s a lot of damage history out there). The resale is quick. The good ones tend to be sold in a week. This is one of the few airplanes that maintains the same level of challenge and enjoyment even after 1000 hours of playing with it.
A new Pitts owner would be wise to fly more than once a week to stay ahead of this thoroughbred, although once acclimatized, it is no harder to fly than anything else. The carbon fiber airplanes will leave it behind in performance, but not fun.

Rick Volker
Via email

I’ve owned, sort of, two S-2Bs. My current B is a no-damage 1993 model. The first was a 1994 that had been repaired following a landing accident. The only modification on my current airplane is a three-blade MT prop. The two airplanes flew quite differently, I suspect the culprit was rigging.

One important location to check the rigging is in the I-strut connection. If you see a large stack of washers on any of the I-strut connections, you can guess that the rigging has been adjusted there rather than somewhere else. In my aircraft, the rigging problems showed up in spins. Spins to the left would be quite different than spins to the right.

There are two weak spots in the airplane. One is the canopy. When reinstalling it, you have to make sure that the emergency release is fully engaged before flight. The other weak spot is the tailwheel. Two types are available from the factory, and neither is really any better than the other. The three leaf springs that support the tailwheel tend to relax over time and hard landings. As the springs sag, the geometry of the tailwheel will change and it will tend to shimmy.

For positive rolling stability, the tail tailwheel unit should not angled 15-20 degrees off the vertical (top forward) when attached to the leaf springs.

Goodyear Flight Custom III tires on the mains will give you about 450 landings. I wouldn’t go cheap on tires, although landing on a flat tire is not a problem. This airplane lands fast because it is not stalled in three-point attitude. It takes a bit of time before most people are able to learn how to land. Takeoff is easy. If you get into trouble, just pull and the plane is flying.

Cross country is a challenge. I go as high as possible—10,000 to 12,000 feet, where it cruises at 145 knots at 11 GPH. If you aren’t back on the ground in two hours, you soon will.

Keith Davis
Via email

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