I remember the time when we were visiting our family abroad and sitting inside the airport for hours waiting for the airplane to arrive. There is this huge window that gives a view of the planes taxing outside a sunny day.
While waiting for the doctor appointment, I saw this newly designed electric fan that blows air from a tube below as a base, upwards and horizontally beside are small holes that pushes the air outwards. Then, it struck me. Why not build a single jet engine at the rear of an airplane which pulls air from vents at the sides. This will lessen the energy to lift the plane.
Here is a rendering of a crude design I built:
2D Rendering of a one-engine commercial jet airplane.
Here is a more accurate 3-D rendering.