Early all-electric aircraft may have very short ranges – but Magpie Aviation aims to help, by using an electric tow plane! Could it work?
There is a lot of research on aircraft that make use of new methods of propulsion, to achieve zero or net-zero emissions. We have seen projects concentrating on making Sustainable Aviation Fuels (SAF) affordable, for existing airliners. For the longer term, a lot of efforts are focusing on hydrogen propulsion or hydrogen fuel cells.
There are also battery-electric aircraft. But the general consensus is that, for the foreseeable future, scaling up all-electric propulsion even to regional airliner sizes, will be challenging. We see several four or six-seat eVTOL initiatives out there. But the energy density of current and near-future batteries means that it will be hard to increase the passenger capacity of all-electrics to double digits, with a meaningful range.
Magpie Aviation to the Rescue?
This is something that Magpie Aviation is trying to change. The way they are planning to do it involves using a battery-electric glider tug, to pull along a battery-electric aircraft, the size of an ATR-42. To do this, Magpie Aviation is already testing its concept using a modified glider and a tow plane.
Normally, a glider tow plane or tug pulls a glider for take-off, releasing it once it reaches the desired altitude. The system that this company is working on essentially does the opposite. Once the system becomes operational, the all-electric aircraft would take off on its own power, attaching itself to a tow plane for much of the cruise portion of the flight.
To test the concept, Magpie Aviation needed to figure out a reliable way to get a glider to re-attach to a tow plane, after release. The method the company used looks somewhat similar to the “probe & drogue” method of aerial refueling. But it is quite a bit more complicated than that.
A clever tow rope?
In aerial refueling, the tanker’s air refueling drogue is simply pulled along, and the receiver aircraft has to aim for it. This requires a certain amount of skill from the pilot of the receiver aircraft. What Magpie is working on, is a drogue-like mechanism that can detect the receiver aircraft and maneuver towards it. This automates the process, making it much easier and more reliable. The company has already tested the process multiple times, with a glider and a tow plane.
Operationally, the all-electric airliner would take off and meet with the first tow aircraft, which will have taken off from a secondary airport. When they meet, the two aircraft would mate, allowing the airliner to idle, conserving energy. The tow aircraft would release the airliner when it needs to land, at an onward or intermediate charging base. A second tow aircraft could take over, for longer trips.
At every stage of the process, the airliner will have enough energy reserves to divert to another airport, if anything goes wrong. Before starting Magpie Aviation, its founder, Vander Lind, had founded Kitty Hawk, an eVTOL company that currently has backing from Boeing. For this latest project, Vander Lind is working with the FAA, to define the certification parameters for the tow aircraft.
Magpie’s website
