When an electric plane is designed for pilot training, one of the first questions is “Can you complete the standard lessons in the e-plane?”.
A team of three instructors from WWFC (Waterloo Wellington Flight Centre) and five pilots from WISA (Waterloo Institute for Sustainable Aeronautics) set out to answer the question by flying a Pipistrel Velis Electro.
The pilots were recruited from the University of Waterloo’s Aviation Program and already had at least their PPL (Private Pilot Licence). The lessons were considered ‘pseudo’ lessons as instructors demonstrated exercises and the experienced students then repeated the exercises. If the students had been ab initio or with limited aviation experience, they may have taken longer to successfully complete each exercise. Following each flight, a survey was completed where the instructor was asked to note which exercises were attempted and of those attempted were they: able to complete; unable to complete; or required to modify each lesson. Comments were welcome to explain the modifications or provide insights related to particular lessons.
A summary of the responses is provided below for each group of lessons:
Take-offs
Lessons were completed for normal, short field, soft field and crosswind take-offs. The first comment from most pilots flying the Velis Electro is about the instant torque and rapid acceleration delivered by the electric motor. In the short field take-off lesson, this is particularly noticeable. Short field comments included: “Very high torque felt compared to normal.” “Took off with flaps 1. Less nose up attitude. Quicker initial climb.” For the crosswind lesson “All take-offs were crosswind” and lessons were completed as planned.
Circuit and landing
Lessons were completed for normal, short field, soft field and crosswind landings as well as overshoots. For circuit and landing lessons, an important feature of the Velis Electro is that it has a glide ratio of 15:1 compared to a glide ratio of 7:1 for a Cessna 172. The comment “Glides better than usual” means that the slope of descent on final will be flatter than in conventional heavier aircraft because the plane will go further when descending with no power. The light and streamlined airfoil is good for energy efficiency, however, one of the crosswind landing lessons found that it was “very bumpy compared to normal, plane is carried up and down by every convectional current”. The maximum take-off weight is 600kg so the plane is lighter than the previous generation of trainers. This gives it a light and responsive feel when flying, but also means that atmospheric turbulence are felt more.
Overall, the Velis Electro is well designed to complete circuit lessons with various take-off and landing scenarios.
Upper air exercises
Standard upper air lessons including steep turns, slow flight, stalls – power on, stalls – power off, and slips were completed as planned. One feature of the current battery capacity is that energy awareness has a bigger role in lesson planning. For example, climbing to 3000ft above airport altitude will take approximately 20% of the battery’s charge. The POH lists the energy requirement as 7% of the State of Charge per 1000 feet climbed (7%SOC / 1000ft * 3 = 21% SOC). As a result, a limited number of climbs are available for each lesson.
The precautionary approach lesson was modified by splitting it over two flights. In precautionary approaches, the pilot still has power available, but must choose a field to land in, instead of proceeding to the scheduled destination. The exercise includes a careful inspection of the selected field from a low-level flight parallel to the field before climbing again and completing the circuit to final, as if you were going to land. To cover the various scenarios that a pilot might face in precautionary approaches, a second lesson would typically be required. The comment was “Lesson cut short to ensure sufficient power on return. Require second flight to complete lesson.”
Forced approaches were simulated with the instructor pulling the power lever to zero and the pilot choosing a field, inspecting the field, planning a safe circuit and lining up on final with a safe height to land in the selected field. Instead of actually landing, they then applied power and climbed back to a regular flight altitude. In this case, the higher glide ratio of the Velis Electro enables the plane to go twice as far from a given altitude compared to conventional trainers. This gives the plane a longer range and the pilot can choose from among a larger number of potential landing sites. If the plane enters a rising column of air, the slower descent rate will mean that altitude can be maintained as noted in the comment: “a lot of up and down drafts, holding altitude for a while before it would descend.” Circuit planning for the chosen field needs to be adjusted according to the local flight conditions.
Emergency procedures
Lessons for emergency procedures were completed. These included lessons for battery over temperature and battery fire that are specific to electric aircraft.
Excluded lessons
In contrast to the long list of lessons that the Velis Electro can do, there is also a short list of what it can not do. The Velis Electro is only approved for VFR (visual flight rules) operations, so no IFR (instrument flight rules) lessons were included. No intentional spins are allowed, so spin lessons must be conducted in a different aircraft. Cross-country lessons were not attempted as this would require a network of airports with charging facilities. (In the spring of 2024, we only fly to Brantford, YFD, as it is the only other Ontario airport with a charger installed.) Current battery capacity also limits the range available for each leg of a cross-country trip.
Overall, the best summary comment from the set of lessons is “All as expected”.
The POH sets out the performance expectations of the Velis Electro and these ‘pseudo’ lessons with pilots and instructors were consistent with those expectations.
Probably the most important difference that lessons in the Velis require is attention to energy management. Flight planning, endurance and range awareness are more focussed in the Velis because of the smaller amount of energy available in the battery in comparison to a conventional fuel tank. However, being aware of the limitations and planning tasks according to energy available is not a bad idea. A side benefit is that it could create a generation of pilots trained and thinking more about efficient flying. That could be good for both environmental and economic performance as we move toward a more sustainable aviation future.
The Velis Electro has been approved for pilot training in Day VFR conditions in over 30 countries and Transport Canada is currently considering its potential for training pilots in Canada. In June 2024, Transport Canada provided an exemption so that Sealand Flight could use the Velis for training a small group of ab initio pilots. Waterloo Wellington Flight Centre and Sealand Flight are working with WISA to provide data and insights to support Transport Canada’s evaluation. We hope to hear a decision about type certification and broader approval for flight training later this year.