By Dave Walsha, Sales Manager, EMS
Despite being hit hard by the pandemic, the aviation industry is finally starting to recover. According to consultancy firm Bain & Company, by the end of this year, global demand for flights will reach 84% of the 2019 levels. There is a growing demand for flights on private jets, too; in 2019 there were some 22,000 private jets registered around the world, expected to grow by a further 7,300 by 2030.
And, whilst customers expect increased comfort and entertainment on their flights, the aviation industry must also address its emissions.
Motorised features are regularly found on aircraft, not least to provide comfort at the push of a button, such as seat adjustment and reclining. In private and business jets, tables, smart device holders, computers, TV screens, etc, are also raised and lowered at the push of a button. Automation of many features, including window blinds, partition walls and armrests is becoming more common – which means demand for motors on board aircraft will only continue to grow. Motors are also used to adjust the valves that regulate pressure in the aircraft’s air-conditioning system.
Also, for most people, surfing the Internet whilst flying is essential, so communication antennas are used to continuously and automatically adjust to provide the best satellite signal – also enabled by motors.
Then, there’s safety: Electric motors on aircrafts are vital in safety-critical applications, such as in the locking mechanisms on aeroplanes for cabin doors, emergency exits and the pilots’ seats, which must remain in a fixed position during take-off and landing. When a plane descends for landing, the landing gear is extended. To ensure it remains in place and landing is successful, a motor gearhead must operate a locking pin.
Before covid, in 2019, aviation accounted for 2.5% of the world’s carbon dioxide emissions, equating to nearly 1000 million metric tonnes, with 29% increase on 2013 levels. This indicates that the aviation industry must act now to reduce its emissions and play its part in the drive towards net zero.
Air travel is expected to surpass pre-pandemic levels, so reducing the number of flights is not likely. A more realistic solution is to reduce each airplane’s fuel consumption, which will also reduce the amount of greenhouse gases released.
Airlines are already taking action to reduce their fleets’ fuel consumption, cutting weight wherever possible through various measures – by using advanced materials, thinner seats, providing pilots with tablets instead of large and heavy paper manuals, and even giving passengers fewer ice cubes for their drinks.
Motors also play an important role in reducing aircraft weight – there is a high number of them on board, so reducing making motors lightweight will also reduce the plane’s fuel consumption.
Electronic fuel injection
It’s not just commercial airlines that contribute to the emissions problem in the aviation industry. Currently, 15% of carbon dioxide emissions come from non-passenger aircraft. While these aeroplanes won’t benefit from motors in luxury features, motors may still play a role in reducing their fuel consumption.
Unmanned aerial vehicles (UAVs) are smaller aircraft used as vital transport methods for the military, emergency services and, increasingly, industry and agriculture for reconnaissance and measurement. To achieve extended flight time using minimal fuel quantities, these aircraft require reliable propulsion systems.
Previously, a carburettor was the only way of achieving fuel delivery to a UAV’s engine. This device provides a combustible mix of fuel and air. However, it is unable to provide an optimum mix of fuel for all the various phases of flight — the ideal mix at sea level is too rich at altitude, yet the optimum mix at altitude is too weak on the ground. This compromise leads to reduced performance and increased fuel consumption.
Smaller aircraft manufacturers are increasingly beginning to turn to electronic fuel injection (EFI) to provide the benefits of fuel injection to smaller aircraft. The system works by injecting fuel, which is under pressure in the system, into the intake manifold using special injectors, with the fuel-to-air ratio being controlled by an ECU (electronic control unit). Sensors in the engine’s intake and exhaust system supply data to the ECU, where it is assessed and the ideal amount of fuel required at a particular point is calculated.
For fuel to burn, using the right mix of fuel and air is essential, so the sensors also help the system to fine-tune the mixture for the load and conditions at each precise moment of the flight. The high pressure of EFI means the amount injected is continuously electronically calculated, even at high altitudes, based on data such as temperature, air pressure and required performance. Because the pressure helps create an extremely fine vaporisation of fuel, it ensures a consistent mix of fuel and air. As a result, using an injection system can reduce fuel consumption by up to 30%.
When designing an injection system for a small aircraft, everything needs to be minimised. The compact system consists of many components, including the injector, a fuel pump, ignition module and a fuel pressure accumulator. These mechanical components need to weigh as little as possible to keep the aircraft light.
A high-performance, low-weight small DC motor can fit compactly into an EFI system to help deliver consistent fuel pressure. The motor helps create the auxiliary energy required to build up the necessary pressure, which powers the fuel pump to deliver fuel and air into the system.
In an EFI, motors must be able to work tirelessly, with low rotor of inertia for fast and reliable acceleration and braking. EMS is the sole UK supplier of Faulhaber motors, which are characterised by their high power and low weight. They can be incorporated as part of this fuel system without contributing to any unnecessary weight gain.
Comfort and safety features can also benefit from reliable motors. It is important that nothing fails or breaks during a flight, particularly where passenger and crew safety is concerned. Maintenance intervals should also be as long as possible. Faulhaber motors are made in a finely-controlled manufacturing process that ensures consistent high quality.
As we take to the skies again, the aviation industry must work to keep its emissions under control. Reducing weight and improving the efficiency of fuel consumption is essential.