Amazing Transportation : February 2014

Recently there has been a shift in paradigm and now science is doing its best to go green. We have come to realize how our inventions have affected the nature and are doing our best to undo those harmful effects and to be more and more environment friendly. One such project was ERO robot that recycles concrete and Project Zero Electric Plane. This was the reason behind NASA’s project known as Environmentally Responsible Aviation (ERA). The ERA’s goals were to reduce aircraft emissions, noise and fuel consumption. This is what inspired the engineering students from the University of Virginia into focusing their time and energy into the simulation of an environment friendly plane. The result of this work is a simulation that employs a hybrid electric plane which is capable of flight with 50 passengers aboard. The team was led by aerospace engineering students; Sohail Ahmad and Kelly Thomas and these undergraduates used Flight Optimization System (FLOPS) to evaluate a number of designs which were based on propulsions systems and airplanes which are already in use. The whole study was carried out to find out if a hybrid – internal combustion engine and electric motor – was feasible for being a passenger aircraft.

The team decided, to make use of the batteries while takeoff and landing since they take place in congested areas and the internal combustion engine (ICE) would be in charge during the rest of the flight. The ICE would be charging the batteries for the landing part too. The test plane was chosen to be ATR 42-600 which is a twin turbo propeller commercial aircraft that can carry 48 persons. The team wanted to see if converting this model would result in a feasible hybrid solution to the problem. Two methodologies were employed; series and parallel. In a series system; ICE works to charge the batteries and powers an electric generator which in turn runs the motor. However, for the parallel system; the propeller is capable of being powered by either the ICE and/or electric motor. Their final conclusion was that the parallel system was more efficient for their design and project.

The batteries are a crucial part of this system and they had to consider a number of factors including the power to weight ratio and life of battery. The modeling they did in FLOPS gave them specifics for the battery they needed. Accordingly they needed energy enough to provide them with a thrust of more than 6,000 lbs at a speed of 368 km/hr. This came down to be 1500 kW per engine. Their final choice of battery was a Lithium polymer battery which ended in a total weight of batteries equaling less than 13,000 lbs.

The final conclusion from the team tells us that in the coming years using this modification approach for an aircraft designed to work ICE would be much more fuel efficient for distances of up to 300 miles and holds a promise for the environment. However, retrofitting the current technology won’t prove to be very fruitful. But they are confident that using the current technology to design an aircraft specifically for the hybrid propulsion system would do the trick. Research is in progress and we wish them good luck. This sure is a work of wonderful engineering.