[Manuel_D]

It's not takeoff that consumes a lot of fuel, it's climbing to cruising altitude. You're not going to get much savings with a launch catapult. A catapult really only helps with shortening the runway distances required to take off (e.g. off an aircraft carrier).

[Sohcahtoa82]

You just need a fast enough catapult mounted on a slope. ;-)

An object dropped at 30,000 feet would be traveling at about 3,000 mph when it impacted the earth, ignoring the atmosphere.

Maybe launch at 4,000 mph to overcome drag to throw something into cruising altitude? We'll just wear some noise canceling headphones to block out the OVERSPEED alarms.

[Arelius]

I mean, isn't ignoring the atmosphere ignoring like 90% of the domain?

[bhandziuk]

Just for perspective this is about mach 5. But I guess there is no speed of sound if you're ignoring the atmosphere :)

[Night_Thastus]

A catapult that launches a commercial aircraft with enough force (over a typical runway length) to get it to cruising altitude with no other power source would also turn all the passengers into raspberry jam.

[Ekaros]

I wonder how much energy would be stored in that catapult and what would happen if something went slightly wrong. Like it got stuck midway... Will we have a plane left? Or how many pieces?

[vidarh]

Brush up on your Jules Verne - clearly the solution is (perhaps not so much) a giant cannon....

[njarboe]

So the ramp needs to be about 35,000 feet high?