>>1639671The involved forces would be extreme. Both the catapult and the aircraft would need to be built for that. Accelerating a 200t aircraft with 1g is a huge structural strain and would increase aircraft weight and airframe wear massively.
To keep acceleration in a tolerable level for passengers, as well as to give the catapult a chance to succeed in the first place, the acceleration distance would need to be pretty long. A mile-long ultra-high performance catapult would be insanely expensive to build, maintain and power. Failure would result in possibly hundreds of passengers, so there's no halfassing allowed.
Runway-capacity would be reduced because such a huge catapult would hardly be able to fire that quickly.
It would get in the way with landings. A seperate strip would be needed for that.
Aircraft would still need to be capable of unassisted takeoff for decades, or risk being stranded eternally shuld they need to detour.
Turbine power could hardly be decreased either, as the machine still needs to climb after leaving the runway.
The engines do a perfectly fine job starting the aircraft and there's little to be gained through this, other than increased risks and costs.
Launch catapults are a nieche application to launch jets needing a mile-long runway on a 0.1mile stretch. When runway length isn't critical, ther's no point.
