Piper PA-12 Cruiser

More useful than a J-3 and cheaper than a Super Cub, the Cruiser flies on as a popular choice for the low-and-slow crowd.

As airplane prices continue to spiral upward and buyers become more accepting of older airframes, classic airplanes are getting new scrutiny as budget birds. The Piper PA-12 is one of those oldies, providing a low-cost entry into the world of utility and fun flying.

The downside, of course, is that these airplanes are coming up on 50 years old. Although parts availability is still good, potential owners should be forewarned of the need to find a competent mechanic with tube-and-fabric experience to stay on top of mechanical concerns.

In many applications, the Super Cruiser is a reasonable (and cheaper) alternative to the Super Cub-a fact not lost on bush pilots. Of the 3760 Super Cruisers built, 1715 are still registered with the FAA-464 are in Alaska.

History
The PA-12s roots were planted before World War II. The three-seat J-5, which entered production in 1939 and continued as the J-5A and J-5B Cub Cruiser, became the J-5C in 1941. In the new incarnation, the C featured a 100-hp Lycoming O-235-2 and a closed engine cowl. The Navy liked the J-5C and ordered 100 to serve as aerial ambulances carrying stretchers out of unimproved battlefield airstrips.

With the end of the war, Piper, just like every other aircraft manufacturer, looked at ways to use its bloated inventory of raw materials to produce civilian airplanes. It had a few leftover J-5 orders from before the war and used the J-5 design to create a modernized variation.

Piper rolled out a highly modified J-5C in October 1945 to test as a prototype for the new Super Cruiser. The prototype was used for flight-testing, after which it was destroyed. The aircraft was certified in the normal and utility categories for land planes and in the normal category for seaplane operations.

Production began with serial number 12-2 at Pipers Lock Haven factory in February 1946 and continued until May 1948. In addition, 234 aircraft were built in Ponca City, Oklahoma in 1947 and early 1948, after which the Ponca City plant was closed. The decision to produce airplanes in two plants was premature. Piper didnt get certification for the airplane until March 1947-13 months after production began.

The post-war aircraft boom turned bust in mid-1947, leaving Piper with a field full of unsold PA-11s and PA-12s as the company struggled to stay afloat.

Features
The changes that warranted a new type certificate were primarily under the skin. The fuselage is nearly identical to the J-5, but in the wings the spars went from wood to metal. The tail surfaces were exactly the same as in the J-5s.

There were a few aerodynamic cleanups, with the wing struts getting aluminum fairings at the top and bottom, and fairings added at the top of the jury struts. The landing gear got new fairings at the fuselage attach fittings, and the shock cords were relocated up in the fuselage under the pilots seat, where three rings were used on each side. The windshield became a one-piece affair and optional wheel fairings were offered. In addition, each wing got an 18-gallon metal tank that was fully enclosed with a metal skin on top of the wing.

Under the cowl-which saw additional duty in the PA-18 Super Cub-the engine was changed to the Lycoming O-235-C. Although still rated at 100 HP at 2600 RPM, the new engine was equipped with an electric starter and generator. The cowl itself was something of a departure, fully enclosing the engine in a way that drew cooling airflow in while attempting to minimize cooling drag.

Late in the production cycle, Piper changed the engine to the O-235-C1, which upped the power on tap to 108 HP continuous and one minute of 2800 RPM that produced 115 HP. The Super Cruiser was also the first Piper to use a muffler that actually worked, and the basic design was used up to the PA-28 Cherokee. In an upstaging of Henry Ford, Piper offered two paint schemes, either red and yellow or red and white.

Handling
Flying the PA-12 is like flying a J-3 on steroids-like modern pilots might feel transitioning from a Cessna 150 to a Skyhawk. The controls are more responsive than the J-3 and the additional power on tap mean the PA-12 is capable of primary training but is more suited to a more advanced pilot.

The airplane is heavy in pitch, making it essential the pilot spin the trim handle located on the left sidewall. When in trim, the pitch heaviness means stability, but any change in RPM requires an immediate trim change to avoid arm-wrestling the airplane.

The airplane can be soloed from either the front or rear seat, but flying solo from the rear means no baggage in the back. Taxiing is typical taildragger. The short front gear struts improve visibility somewhat.

Its different from most taildraggers, however, in that the wings angle of incidence is flat enough that a full-stall landing is not possible without landing tailwheel first. That means the airplane tends to float on landing and will take off in either the three-point or tail-high position.

Using trim on approach helps solve a couple of problems. Proper trim yields about 70 MPH on downwind and base. Crank the nose up a bit on final, reducing speed to about 55 MPH, and you’ll likely be just about full nose-up on the trim wheel if flying solo from the front. The airplane will practically land itself at about 42 MPH.

Brakes are adequate, but the airplanes short landing rolls are such that brakes arent needed much on the ground other than to make pivoting turns or short-field landings.

One aspect of the airplanes handling demands attention, particularly for those who fly to the limits of the airplanes endurance. The fuel lines run from the back of the fuel tanks, and during descent the tanks can unport if the fuel quantity is low. Unfortunately, lousy fuel gauges mean you don’t really know when that will happen.

The fuel gauges are glass sight tubes that extend downward from the wing. Floats and wires within the glass tube are supposed to indicate quantity, but like most fuel gauges of the era they are so inaccurate as to be ignored.

In an effort to reduce the problem with the fuel unporting, Piper added a two-gallon header tank between the cabin sidewall and the outer cowl.

The tank is located in the fuel line between the tanks and the gascolator and holds only a small quantity of fuel. In later airplanes, the leak-prone tank was removed, further increasing the odds of unporting.

The fuel port situation means pilots should plan for fairly leisurely descents when fuel is low, especially when descending from relatively high altitudes.

With the original 100-HP engine, the Super Cruiser cruises at about 105 MPH. The later engine doesnt add to the cruise speed, but shortens the takeoff length and adds about 100 FPM to the climb rate.

The book puts the takeoff run at 720 feet and the landing roll at 470 feet in the normal category. The maximum useful load is about 800 pounds per the factory and perhaps 750 pounds in a real airplane. That gives enough useful load to carry three FAA-standard adults and full fuel, or two people and more than you can fit in the baggage compartment. Operating in the utility category means a 250-pound lower gross. With full fuel, the Super Cruiser has a range of about 600 miles, burning 5.8 to 6 gallons per hour.

The front seat is small and a little narrow, but its very comfortable for even large people. The seating position is good, with more than adequate legroom. All controls are easily within reach. The biggest front-seat shortcoming is that getting in and out requires gymnastics due to the position of the seat we’ll forward of the door.

Rear seat room is outstanding for one person and cozy for two. The two-place rear seat is 31 inches wide at the hip and 33.5 inches at the shoulder. To make life better for rear-seaters, the aft stick comes out easily and can be stowed in the back.

Factory standard seats originally were vinyl-covered inflatable cushions, which later gave way to a more conventional vinyl-covered horsehair cushion. Cabin ventilation is good. The left side window slides open to let in air on the ground or in flight. The cabin heater works well, too. As the airplane came from the factory, the heating vents doubled as fresh-air vents if the heater was turned off.

Compared to the prototype J-5C, the Super Cruiser boasts an enlarged instrument panel, with factory-original sporting a two-tone hammertone paint job.

The panel was designed with optional instruments in mind, although by modern standards, its extremely small. Metal overlays fill any blank holes and frame the instruments that are installed.

The electrical controls were housed in a metal panel on the right sidewall, just forward of the door. Navigation lights were standard and a landing light was optional. The Cub-standard heel brakes included a cable linkage to a handle under the right side of the panel that served to actuate the parking brakes.

Fuel System
Early in the production cycle, the fuel system was changed to delete the small header tank. The original configuration included two fuel shutoff valves on the lower left forward sidewall. The forward valve stopped the fuel flow entirely just downstream of the header tank. The aft valve shut off flow from the right wing and was supposed to be open only in level flight.

When the header tank was removed, the valves were relocated farther aft. The top valve controlled the right tank and the lower valve controlled the left tank. Both were intended to remain on normally and to be used to correct a fuel imbalance or shut off the fuel in case of emergency or maintenance.

The fuel tanks themselves have caused their share of problems. Made of thin-walled steel known as ternplate, the tanks were soldered together. Inside, two longitudinal baffles were spot-welded to the upper and lower skins of the tank. After decades of fuel sloshing inside the tanks, the baffle welds can tear loose. In addition, the seams can crack, leading to fuel leaks. The tanks can be removed, purged and re-soldered, but many owners opt to use epoxy patches as a more durable and practical solution.

Maintenance
As you might expect with such an old airframe, there are several areas where close attention to maintenance is important. The airplane originally used wood wing tips and steel tubes in the trailing edge of the ailerons and wing struts. Weep holes in the fabric are crucial to preventing moisture from deteriorating the internal structures, and its a good idea to periodically inspect underneath the fabric.

The wing struts have had many service letters and ADs against them over the years, mainly because of internal corrosion that eats through them from the inside out, but also due to fatigue on the bottom end of the steel strut.

A new style sealed strut is available from Univair Aircraft Corp. in Aurora, Colorado that solves the problem with corrosion. The struts also feature a larger fork at the bottom to preclude cracking.

The landing gear assemblies on some of the earlier models have also had their share of troubles. They had a thin steel strap running from the inboard end of the axle to the inboard end of the main gear tube where the shock cords are. The welds at each end of the strap were prone to cracking, so Piper modified the part in the field by welding a streamlined tube over the strap and beefing up both ends. Later, the gear was redesigned entirely.

Otherwise, the gear is typical early Piper fixed gear: trouble free. Only two landing gear accidents occurred in the five years we studied. One of them involved a wheel falling off on the first flight after the student pilot changed from skis to wheels. The other involved hitting a rock adjacent to a 30-foot-wide runway in a bush operation.

There have also been reports of cracks in the aileron bellcranks, which are usually traced to improperly torquing of the cast aluminum components by a ham-handed mechanic or pilot/owner. Aileron hinge brackets have also been occasional trouble spots, with cracks spreading where the hinge attaches the aileron to the trailing edge of the wing. Beef-up kits are available from Univair.

Additional inspections should be made of the rudder pedals. The pedal return springs are wrapped around a pivot tube, but the springs are hard steel and the tube is thin-walled steel. Throw in some dirt from the floor, and the springs can wear through the steel tubes over time.

Mods
By some accounts, the PA-12 boasts more mods than any of the other vintage Pipers. Hundreds of STCs have been issued for PA-12s, including vortex generators, new vertical stabilizers, flaps, 24-gallon wing tanks, and metal or fiberglass wing skins – as we’ll as a variety of engine and propeller combinations.

STCs are available for Cleveland and Bodell brakes, installation of skis or floats, PA-18 Super Cub landing gear, tundra tires and various tailwheels. You can also get extended baggage bays, left side doors, door removal, increased gross weight, various tail surfaces and auto fuel.

Approved powerplants include Lycoming engines with 125, 135, 150, 160 and 180 HP. Boosting the power so dramatically usually includes staples such as oil coolers, but also can mean larger, balanced control surfaces, beefed up cowlings and other components that will get beaten up by the stronger prop wash.

Univair Aircraft Corp. is a primary source of PA-12 parts, both original manufacture and parts made under the companys own PMA. Univair, 888-433-5433 or www.univair.com, offers both print catalogs and a Web site search engine to narrow down parts applicability. The company also reprints original manuals, parts catalogs and all of the factorys service bulletins, service letters and service memos. Aircraft Spruce & Specialty is another good source for parts. Aircraft Spruce & Specialty, www.aircraftspruce.com or 877-477-7823, offers a similar comprehensive range of parts and publications that apply to the aircraft.

Owners Organization
The Cub Club (1002 Heather Lane, Hartford, Wisconsin 53027-9045, 262-966-7627) is one of the largest of the type clubs for Piper Cubs, and the Super Cruiser falls into the Cub family. Membership is $25 a year and includes a newsletter with technical advice and parts information. Another good source of technical information is Charlie Center of Crosswind STOL in Wasilla, Alaska, who can be reached at 907-376-8069.

Owner Comments
I have owned my PA-12 for six years and, without question, it is a wonderful airplane to own and to fly. I used to own a Mooney and currently own an A-36 Bonanza as well, so I have some good points of comparison.

I bought my PA-12 on wheels and added floats six months later. As a 2000-hour pilot, the transition to tailwheel flying was an exciting new dimension to my aviation activities. I developed a new level of appreciation for those pilots Ive watched over the years bouncing down the runway in Piper Cubs, Citabrias and the like. This was a new challenge for me and I loved it-after I got the hang of it that is.

As for water flying, its the most fun form of aviation Ive ever experienced. The PA-12 is perfect for it if your loads are reasonably small and the winds are not too strong.

With the Plexiglas skylight installed, the cabin is roomy and comfortable for the pilot and passengers. don’t assume this is a good three-person airplane though. The back seat is just too small for two full-size adults to sit comfortably for any long period of time.

The airplane has become very popular with bush pilots, who have recognized its great STOL performance, low operating costs, reasonable load carrying characteristics and ease of maintenance. But don’t buy one if speed is your objective. Mine trues out at 105 MPH with wheels and 95 MPH with the floats.

Purchasing a PA-12 is no easy task for two reasons. First, you’ll never find one that is in the same condition as when it left the factory. That means lots of work has been done on the airplane-sometimes by qualified mechanics, sometimes not. The airplane is so simple, many owner/pilots tackle the work themselves, often neglecting FAA standards. As a fabric-covered metal frame, the airplane is subject to corrosion, so a careful pre-purchase inspection is mandatory.

The other reason these airplanes are difficult to buy is that they have become so popular with seaplane operators that they get scooped up very quickly.

If you find one you like and it checks out clean, don’t be too hesitant or you’ll be back to shopping again in no time. It took me over a year to find and purchase mine. (The first one I settled on failed the pre-purchase inspection and eventually had to have the engine replaced because it was not properly STCd for the PA-12).

Although the airplane has not been manufactured for years, parts are still readily available. I buy from Univair and Aircraft Spruce & Specialty and have never had a problem. Both are we’ll stocked and customer-oriented.

There are many modifications available for the PA-12 and they are worth looking into. Some improve the performance and safety of the airplane significantly. My aircraft had its engine upgraded from 105 HP to 150 HP and, when lightly loaded, it comes off the water in five seconds. Its amazing performance.

The airplane burns 9 GPH and is STCd for auto gas. Other mods on my aircraft include PA-18 tail feathers (larger balanced rudder and stabilizer), PA-18 gear, PA-18 flaps, larger fuel tanks (60 gallons total) and extended baggage compartment. They are all excellent and worth adding if funds permit.

I joined the Cub Club and recommend it highly. They have a complete collection of STCs for virtually every mod available.

Because the airplane is so simple, maintenance costs are quite low. My annuals cost approximately $400 plus any special additional maintenance required. Be sure to keep the fabric and paint in good condition to avoid dangerous and costly corrosion.

I keep my airplane hangared in the winter and on the water in the summer. So far, the paint and fabric have held up we’ll and I expect them to last for many years. Ive been told that todays fabrics should last 35 years if cared for.

Of course, the most wonderful aspect of this airplane is the way it flies. It is truly a dream airplane. With the flaps extended, it wont break in a stall; it just mushes down at about 300 FPM with the nose slightly below the horizon. It seems 60 MPH is the magic speed for almost everything: climb, descent and traffic pattern.

I have enjoyed my PA-12 more than any other aircraft Ive owned and expect to continue flying it for years to come. If you enjoy low and slow, and don’t need to carry too much, this is as good as it gets.

-Douglas Kahn
Camden, Maine

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My first aircraft was a 1947 PA-12 Super Cruiser that I purchased in 1967 and flew from Jacksonville, North Carolina to San Diego in 1968. I had just obtained my pilots license in an Aircoupe and had about 15 additional hours under my belt at the time.

The sellers provided one hour of taildragger transition at the time of sale. Fortunately, that aircraft was most forgiving and let me think I had mastered it within a minimal time. Since there were no flaps, slips to a landing over 50-foot trees were the norm in the 1200-foot field where I learned to fly.

I never learned wheel landings, but found the best method was to touch the tail wheel just a wee bit before the mains and it never bounced. One just needed to stay on the rudders and off the brakes until it was about ready to stop and it never acted like it wanted to run away.

The trip to San Diego proceeded from Jacksonville as a series of three-hour cross-countries to Denver, south via Pueblo to Albuquerque, and west via Phoenix to Gillespie Field.

I flight planned for 100 MPH at 6 GPH fuel consumption. My bladder could only stand three-hour legs, so fuel was never an issue with 36 gallons aboard. Crossing the mountains at 11,500 feet really taxed the service ceiling with the original Lycoming 108 HP engine.

Subsequently the needs of a new family overcame the need for new fabric and I sold the airplane. I still miss it. My current aircraft is a Cherokee 140 that performs about the same, has one more seat if you have small people and uses about 2 GPH more fuel.

-Chuck Chiles
via e-mail

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I use the PA-12s for seaplane training and I love them. I put some pillows in the back seat so I can see the panel over the shoulders of the students and I can reach everything I need to from the back.

The students all enjoy the experience of having great visibility and no one beside them. Most of them have never flown with a stick before, so that is new and fun for them, too. We have two of them on floats; one has 135 HP and the other 150 HP.

I like to use the one that has the 135 HP engine because they have to work to find the sweet spot on the floats. Most of the pilots prefer the 150 HP that has great performance and gets out of the water quickly. The 135 HP, however, doesnt like hot humid weather.

The PA-12 has much more legroom in the back than the PA-18 does. I can stretch out and fly for hours sitting in the back. In the Super Cub, I can only last for about two hours and I need to get out and stretch my legs. The center of gravity is a little further forward in the Cruiser than in the Super Cub, so a little extra back pressure is necessary so the floats don’t grab when landing. Other than that, it flies like a dream. I love them both.

The airplane with 135 HP burns 6 GPH and flies 90 MPH. The one with 150 HP burns 9 GPH and flies at 90 knots. Both fly faster with one person in the front, sometimes as much as five knots faster.

As for the floats, one has Baumann 2100s and the other is on Edo 2000s. I think the Baumann float is very we’ll built, but it needs to be a little longer in the bow. When doing plough turns, the outside float digs in too much for my taste.

The only work we have done other than the normal 100-hour and annual is changing the door on one to a seaplane door. If we need to hand prop the plane we need to get back in without having to swing under the wing strut and run the possibility of falling in.

The seaplane door swings all the way forward flush with the airplane. This requires changing the fuel gauges that otherwise hang down under the wing, but the door is important.

The PA-12 is a three-place airplane. Its great for taking the grandchildren or two small adults in the back. The maximum weight for the rear seat is 340 pounds, so that gives a lot of latitude. All in all, its a great plane for me to use and have fun with.

-Mary Tait
Naples, Maine


Also With This Article
Click here to view “Piper Cruiser Safety: Groundloops, CFIT Lead the List.”
Click here to view “Resale Values, Cruise Speeds and Price Comparisons.”