A Cessna 172 holds the record for the longest endurance flight in history: 64 days, 22 hours, and 19 minutes from 4 December 1958 to 23 January 1959. Flying over Nevada and California, pilots Robert Timm and John Cook took turns at the controls while the other rested. During their world-record flight, Timm and Cook flew 150,000 miles nonstop, the equivalent of six trips around the world. To complete the endurance flight, they used some innovative modifications and methods.
Cessna introduced the 172, a single-engine, high-wing four-seat plane, in 1956. The standard engine was a six-cylinder Continental O-300 that produced 145 horsepower and handled a maximum takeoff weight of 2,450 pounds. The 172’s normal range was about 736 miles at 140 miles per hour.
Pilot Robert Timm Requested a Special Engine
The aircraft Timm and Cook used had about 1500 hours on the airframe and about 450 hours on the engine. Timm decided early on to replace the engine. He contacted Continental Motors and told them about the plans for the long flight. He asked if they would provide a “special engine,” and they agreed.
It wasn’t until years after the flight that one of the mechanics working on the 172, Irv Kuenzi, found out just how special the new engine was. According to Kuenzi, Continental’s sales manager worried that if they built and donated a special engine, others would soon be asking for the same thing. The manager then told a fellow worker to go to the production floor and pick the new engine she liked best. Continental sent this “special” engine to Timm and Cook.
Innovative Ideas for Combustion Chamber, Oil, and Spark Plugs
A certified mechanic, Timm was concerned that carbon might build up in the engine during the flight. He devised a solution: install a system that would squirt alcohol into the combustion chamber of each cylinder.
Another issue was maintaining the engine oil and spark plugs while airborne. Oil changes typically occur every 50 to 100 hours, so that would not be possible in flight. To address this, Timm and Cook designed an electric pump system to circulate fresh oil from a reserve tank while draining the used oil into another tank.
They realized spark plugs would probably need to be replaced. To this end, they carried spares and tools and installed access panels over the engine cowling. Timm and Cook could open these panels and change spark plugs while the engine was running. After this, they still needed to modify the plane’s interior.
Interior Modifications Made Space for Sleeping and Supplies
The modifications included removing all furnishings except for the pilot’s seat. They put in a foam mattress and storage for food, water, and other supplies. They added a small stainless-steel sink for washing in the aft of the plane. Yet another modification was to replace the co-pilot’s door with a folding door and a small platform or step to make it easier to bring supplies onboard.
That left the question of fuel. Timm and Cook installed a 95-gallon belly tank to supplement the 47 gallons the plane carried in its wings. Adding the tank required attaching an electric pump to transfer the fuel in the lower tank to the wings. Of course, this was not enough fuel for what they hoped would be the longest endurance flight ever.
A Unique Ground-to-Air Refueling Method
Initially, Timm and Cook considered using air refueling from other aircraft but ultimately decided that would be too expensive and complicated. So, instead, they chose to rely on a ground-to-air system. For this, they fitted a truck with a fuel reservoir, a fuel pump, and a hose. The pilots would lower a winch from the Cessna to grab the hose and pull it up to a connection on the belly tank. The pump would fill the belly tank in about three minutes.
While this happened, the truck needed to be on a long, straight stretch of road. The plane and truck also had to be at identical speeds, which required skillful drivers and close coordination. The Cessna 172 cruised at 140 mph and would stall at 54 mph. During the flight, they refueled the plane twice daily and 128 times in total.
The pilots needed other support besides fuel. They lowered a bucket tied to a rope, and ground crews would fill it with food, water, and other supplies.
Flight Stayed Mostly Over Desert Areas of Southwest U.S.
Timm and Cook took off from McCarran Field (now Harry Reid International Airport) in Las Vegas on 4 December 1958. They mostly stayed over open desert areas between Las Vegas and Blythe, California, during the flight.
Each Pilot Took Turns Flying and Resting During the Flight
They established a schedule of flying and resting on four-hour shifts. The plane also had blankets, pillows, and a foldable camp toilet. With this schedule, it was no surprise that they suffered from fatigue, which almost led to disaster. Before dawn on 9 January 1959, the 36th day, Timm fell asleep at the controls. Luckily, they were at 4000 feet at the time, and the wing-leveler autopilot on the plane kept it steady.
Finally, on 23 January 1959, as maintenance issues became too critical, Timm and Cook decided to land. By then, the autopilot had cut out, and the generator, tachometer, cabin heater, landing and taxi lights, belly tank fuel gauge, electrical fuel pump, and winch had all stopped working.
The Record-Setting Endurance Flight was a Success for the Pilots, Plane, and Sponsor
They touched down at McCarran after setting a record for endurance flight that still exists. In every way, the flight was a success. The pilots were safe, and the mission proved the reliability of the Cessna 172. It was also a successful promotion for the Hacienda Hotel in Las Vegas.
Its owner, Warren “Doc” Bailey, had viewed the flight as an opportunity for good publicity, and he agreed to sponsor it. This covered costs for the modifications, fuel, and other supplies. During the flight, the hotel’s cooks provided meals for the pilots. Bailey did ask that “Hacienda” be painted in large letters on each side of the fuselage.
The hotel also rewarded Timm and Cook well for their successful mission. They received $1000 for each day of the flight and an additional $10,000 for breaking the endurance flight record. Their Cessna 172 is now on display inside the baggage claim area at Las Vegas Harry Reid International Airport.
