The Ampaire 337 is a Cessna 337 Skymaster with its rear, 210-horsepower Continental engine replaced with Ampaire’s proprietary electric-propulsion system. This is essentially a battery-powered electric motor. Although called a hybrid-electric airplane, it is not a hybrid in the sense of a hybrid automobile. The two powerplants are completely independent of one another, and the lithium-ion batteries that power the motor cannot be charged in flight.
Ampaire refers to this combination of powerplants as a “parallel hybrid,” meaning that “the two independent sources of power work in concert to optimize power output.” In its current configuration, the batteries must be charged following a flight or replaced with a charged battery pack standing by on the ground, a process that will eventually be accomplished in less than 15 minutes. In the 337’s final configuration, the ship’s batteries will occupy part of a cargo pod attached to the belly of the airplane so as not to take up space in the cabin.
The centerline-thrust Cessna Skymaster was the obvious choice for this Experimental aircraft because it allows differences in thrust to occur without creating any yawing (such as could result from different types of powerplants mounted on opposite wings of a conventional twin-engine airplane).
Although the motor installed in the aircraft is capable of producing 180 kilowatts of power (240 horsepower), it currently is limited to an output of 160 kW (215 horsepower) so as not to exceed by much the maximum power for which the airplane was originally certified. Fully charged batteries enable the motor to generate maximum power for 5 to 6 minutes but last substantially longer at lower power settings.
The electric propulsion system adds approximately 400 pounds to the empty weight of the airplane, but this enables the aircraft to be flown with a relatively light load of fuel. As a result, useful load remains approximately the same.
Charging the batteries takes about two hours. The cost of the electrical energy needed for charging is less than half the cost of the equivalent amount of avgas.
The electric propulsion system is 85 percent quieter than the reciprocating engine that it replaces. What noise remains is created solely by the three-blade, variable-pitch propeller moving air rearward.
The company plans to eventually developing single- and twin-“engine” airplanes powered solely by its proprietary electric-propulsion system(s).
Ampaire’s electric propulsion system is not yet practical for use by individuals because infrastructure is required at en route and destination airports to charge and exchange replacement batteries.
Cirrus names new CEO
A veteran marketing executive with years of experience at automotive, audio, and building materials manufacturers is the new CEO of Cirrus Aircraft. Zean Nielsen succeeded Cirrus co-founder Dale Klapmeier as CEO effective June 3. Klapmeier, a National Aviation Hall of Fame inductee, announced in December his intent to transition from CEO to adviser.
Cuba closed to private pilots
Two years after President Donald J. Trump first announced his intent to reverse Obama-era changes easing restrictions on travel to Cuba, a final rule effective June 5 closed the door for most of general aviation. The Department of Commerce Bureau of Industry and Security implemented additional restrictions on travel and commerce with Cuba, further limiting options allowed under the previous administration.
U.S. Sport Aviation Expo canceled
The annual U.S. Sport Aviation Expo, hosted at Florida’s Sebring Regional Airport since 2003, has been canceled effective immediately, the airport authority announced May 30. A farewell message posted on the official website thanked attendees for “15 incredible years” after the January 2020 event was scrubbed.
Avionics pioneer Gary Burrell has died
Gary Burrell, the aviation pioneer who developed the first successful navigation/communications product for general aviation and would go on to co-found avionics powerhouse Garmin with his colleague Min Kao, died June 12. He was 81.