Multiple energy generators can together be an efficient and safe energy system. Just 1 energy generator can not be efficient because the demand for power varies. For example: If an IFO needs 100 KiloWatts for cruise speed, one could design an engine that produces 100 KiloWatts very efficiently. But when the demand during VTOL on Earth is 1000 KiloWatts; the small engine can not deliver that. An efficient 1000 KiloWatts engine can deliver it, but is not at all able to produce only 100 KiloWatts in an efficient way. When using two engines: one just for VTOL and one just for cruise, than there is always one being useless weight. But when building two engines that can combine their power, one optimized for 100 KiloWatts and one optimized for 900 KiloWatts, than they can work together during VTOL & acceleration.
In case of an engine failure there is trouble of the emergency kind. One can therefore build the energy system from 10 x 100, or 2 x 400 + 2 x 100, or what ever combination that makes 1000 KiloWatts together. If one engine fails, an emergency landing can be made safely.
The power for cruise speed must be created in an energy efficient way because this power demand is there almost almost all the time. But the maximum power generated at VTOL & acceleration may be less energy efficient IF it is from an engine that has less mass. Less mass = less mass to thrust = energy efficient.
One more option is to NOT use a powerful engine for VTOL, but to store a lot of energy produced by a small light fuel efficient engine, and be able to use all of it during VTOL or acceleration. Some Gyro-planes take-off like that.
The engine
A VTOL aircraft is often build around its propulsion system. We need an energy efficient system that creates linear gravity for lift/thrust. But we don't have that yet, so we have to use the best of what's around today.
VTOL, especially the taking off part, is extremely power consuming. During cruise flight, lift better be produced by a lifting body or such, otherwise you'll be out of fuel soon. And a VTOL with no rotor can't land safely without power, like a helicopter can with auto rotation.
An aircraft's engine needs to be/have:
- Powerful
- Lightweight (a good power to weight ratio)
- Realible
- Energy efficient (fuel = weight, money, polution, dangerous)
- Small
- Minimal vibrations
- Responsive
- Variable power output
The best of the best at this moment are:
- Gas turbine engines
- Wankel rotary engines (like the
Freedom's Rotapower engine and
Mistral Engines)
- Radial diesel piston engines (like the
ZOCHE aero-diesels)
The power source
Extreem amounts of energy are stored in mass.
Some think that vacuum space is also loaded with energy.
Matter-Antimatter reactions -if possible- seems to be the most powerful energy source.
But the aircraft engines we use today, use chemical energy, with a very poor weight to energy ratio, relative to nuclear power.
Stars know how to free energy from mass, and we have solar panels, so that is one good option. Solar energy is free and without mass, but not very powerful.
