Mechanics in History: Penny For Your Thoughts

July 6, 2007
A Pratt & Whitney tradition — Since when?

The first penny I saw affixed to a Pratt & Whitney engine was on the nose of a fully restored AT-6C owned by Jim Levrett, a retired captain with FedEx (he hired on when it was still Flying Tiger Airlines). Levrett is now an AI who works on his own aircraft in a sumptuous hangar at Kingman, AZ. I accepted his invitation to take an air tour over Lake Havasu in his warbird last year, (spectacular!) and from his photos I already knew this “6” was a “10.”

There are few moments as dramatic as driving up to a spartan line of corrugated T-hangars which all look the same — until the heavy sliding doors slowly push open to reveal a colorful, shiny classic vintage aircraft like the AT-6. Levrett’s plane looked deceptively tame in the hangar, as he described the seven-year restoration. From tail to nose — the canopy, the rivets — everything screamed powerful, dependable, enduring. “Most of the airplane came from Conroe, TX,” says Levrett, “I took it apart to the last screw. The Pratt & Whitney 1340 power plant [600 hp] was purchased and rebuilt by Tulsa Aircraft Engines in Oklahoma. I’ve been flying this plane for about four years now.”

Safe from Arizona’s frequent wind-blown dirt, the engine looks like it just came off the assembly line at Pratt & Whitney. Up close and personal I noticed the penny, inserted and held in place with tiny stainless-steel wires which crisscrossed over the recessed inner diameter of a large nut. (Levrett described it more precisely as a “safety wire over a press-fit threaded insert on the sump cover.”) Many important aspects of engine parts, performance and history would surely have captured the attention of a pilot or mechanic, but I was transfixed by the penny. How did it get there and why?

Myth, superstition, and habit

The experts to ask are those who study and build engines as a profession. Graham White, (no relation to the famous English Pioneer Era aviator, Claude Graham-White) is vice president of the Aircraft Engine Historical Society Inc. located in Huntsville, AL. Author of several books, including “Allied Aircraft Pistons of WWII,” White speculated that the tradition had nothing at all to do with Pratt & Whitney manufacturing practices and most probably began following WWII, when engines were overhauled in the transition from military to civilian use.

Despite White’s pessimism that no one at Pratt & Whitney would know, much less care, about restored engines, retired P&W engineer Roger Bursey responded quickly to my request for help. This sentimental homage to an engine overhaul appeals to our Yankee ingenuity and is obviously not restricted to mechanics. Bursey enthusiastically contacted the P&W company historian and fellow retirees who might provide clues. Bursey writes, “I find your subject very interesting ... I have received information that the bolt head accommodates the precise size of a U.S. penny by coincidence, not [by a P&W] design or spec.” This requires some documentation to be sure, but it seems probable.

Levrett explained that he placed the penny on his engine himself as soon as he received it from Tulsa Aircraft’s top wrench Sam Thompson in Tulsa. Levrett picked up the custom from a crop duster, who wouldn’t think of flying without a penny on his own P&W. Pressed for further information on where the tradition began, by whom, and when, Levrett drew a blank.

“It’s just one of those things some of us do, but probably don’t know why.” He speculated it could be placed there to signify the last overhaul, like a date stamp, but suggested that I speak to mechanics who specialized in P&W engines. When asked, Thompson and his shop foreman, Rex Vaughan had more than one answer because each customer had a different reason for placing a penny on the engine. Some preferred to keep the power plant’s original penny for good luck and some insisted it be replaced with a coin dated the same year as the overhaul.

“Mary Dilda races her AT-6 (“Two of Hearts”) at Reno and has a world qualifying speed record with her P&W,” says Vaughan with pride — “I know for sure there’s a penny on that engine.”

Levrett also referred me to Nick Mangel, owner of Aero-Engines in Los Angeles, CA, which has been in business overhauling round engines since 1955. Nick soon had two reference books in hand: “The Aircraft Engine and Its Operation” and the “Aeronautical Vest Pocket Handbook” (both by Pratt & Whitney). The former listed dozens of aircraft which used P&W R1340, R1690, and R2800 that could have started the penny tradition. (The 985 engines may have pennies, but are not easy to see.) At this point I decided I had to limit my penny quest to the R1340 WASP engines of which Nick quoted statistics of 34,966 produced between 1925-1960. I also narrowed down the Wasps to those used on the AT-6. These planes were first manufactured in 1940 (“Two of Hearts” was built in 1945) and many were demilitarized, used in foreign countries, and then returned whole or in parts to the United States. My AT-6/R1340 exclusive did not last long.

“I’ve had engines come up to my shop from Pensacola [FL], preserved you might say, untouched since they were made, with pennies on the engine dated in the 1930s,” says Mangel. I was back to including pennies on Wasps and Hornets prior to WWII for all kinds of planes including Lockheed Vegas, and Chance Vought-built Navy observation aircraft. Wiley Post’s Vega used the same P&W around the world twice between 1931-1933.

Amelia Earhart’s Vega used the P&W power plant for her solo flight across the Atlantic in 1932. I don’t know if either engine was penny-less.

Ever since that day in Kingman, I purposely look for more pennies. On a whim I visited the hangar at Falcon Field, AZ, belonging to Air Response Inc., where three generations of aircraft mechanics work side-by-side overhauling radial engines. Gene, Ed, and Billy Packard work together like one of their fine-tuned engines. Billy led me to an AT-6 adorned with a P&W engine which they maintain for a client. “We re-assembled this entire plane.

The engine came from Sam Thompson in 2003 with a penny already in place,” he said, pointing to the ‘03 penny. “We mostly work on Wrights here but if I overhauled a P&W I’d put a penny on it, because my dad does it. My dad does it because his dad does it.” Even though we didn’t solve the penny mystery I’ll be back to interview Granddad Gene, Dad Ed, and young Billy another day.

My next encounter with a penny on an engine occurred at the restoration hangar for the Southern California Wing of the Commemorative Air Force (at Camarillo). As the guest of veteran pilot and CAF volunteer, Ceci Statford, I met Col. Joseph Peppito, chief maintenance officer, who gave me a tour of their facility. The shop was a flurry of activity with a dozen volunteer mechanics working on the “China Doll” (C46),” a vintage Fairchild, and engines for a restored Hellcat, a Bearcat, and a Spitfire. Peppito gracefully answers visitor’s questions while overseeing five or six separate projects at one time. Amid disarticulated props, wings, wheels, and engines Peppito led me to two P&W engines adorned with a penny. He could not recall the first time he’d seen it done, but he was certain he had read about it “somewhere in a magazine.” So far, he hasn’t been able to locate his source, but I doubt he’ll ever give up looking.

Mariners toss in their two cents

Although less common, pennies can be found on P&W engines other than set into the bolt, which means the tradition is loosely interpreted by an A&P as to how and where it is affixed (for example on 985s). Skip King, AI at McClellan-Palomar Airport in Carlsbad, CA, showed me 985 engines on a Twin Beech and an SNJ with a 1340. I peered inside the cowlings but found no pennies.

Although he had not heard about this particular practice, retired US Airways Captain William Wilkerson shared another tradition known among commercial airline employees about P&W’s artistic, if not historic, logo. “About 10 years ago I happened to learn that Delta Airlines assigned the honor to a specific mechanic for maintaining each new plane with a P&W engine,” Wilkerson recalls. “The mechanic chosen for the job was allowed, and, in fact, expected to, remove the P&W logo, sometimes adapting it as a belt buckle.” Apparently not restricted to Delta, the origin of this tradition may prove equally as difficult to track down as the pennies — another day.

Capt. Wilkerson received his A&P license at the Baker’s School of Aeronautics in Nashville, TN, during 2004, in between flights across the pond in an Airbus. “I have always enjoyed working on my own plane [a vintage 195 Cessna] and now as an A&P I have an added feeling of confidence in its performance.” Wilkerson is considered an expert fly-fisherman and also holds a Marine Captain’s certificate. His curiosity and search for answers has no bounds. Similar in nature, is Neil Marshall, a marine archaeologist from California who I ensnared into a brainstorming session. Without hesitation Marshall made the analogy between the copper penny on a power plant and a mariners’ tradition dating back to Greek and Roman cultures.

According to his research, at the time of ship construction, a coin was placed under the foot of a mast inside the socket called the “mast-step,” for various reasons. Legend and myth suggest the coin was a good luck piece, or that sailors stashed their toll across the river Styx, or as a tithe to the god of the Winds. So steeped in custom has this become that it continues today, although no two boat or ship owners agree on why.

Archaeologists, wreck divers, and treasure hunters have depended upon salvaging these coins as a way to determine the earliest date a ship could have sunk (terminus post quem). Mariner Wilkerson threw in with Marshall’s engine/mast-step analogy. “Commercial airlines [and the military] which own hundreds of aircraft keep engine logs in a central place, whereas the private pilot might keep his book at home or in the hangar,” says Wilkerson. “The engine logbook rarely follows the engine, so it makes sense that under some circumstances the penny date could help in evaluating repairs.”

We will have decades ahead to ponder pennies on airworthy P&W engines. As Jim Levrett put it, “These are still some of the best piston engines going. Some were developed long before WWII. Their reliability and performance continually evolved especially with the introduction of leaded high octane fuels. Many have lasted over 60 years, and if maintained properly, they’ll probably last another 60.”

In the future, Levrett, White, Bursey, Peppito, Mangel, Thompson, or Wilkerson may call in another clue to resolve the origin of the P&W engine penny. That is, unless an AMT reader knows the answer already. If so, contact editor, Joe Escobar and we’ll follow up. I’ll personally send you a 2007 penny for your thoughts.