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747 rail gun

Trying to make a kickstarter for this laughable project but some numbers.

max take off weitght=439985kg Crusing speed = 920 km/h

27359 km/h Orbital velocity 20kg payload.

(439985920- 2735920)/439965 = 918.79 you’d only lose like 2km/h on the plane

Air pressure is 14% of sealevel at 747 cruising altitude

From brad: Looks like 70000kg of capacitors will get you 10.4M Wh of energy storage I’m getting 563M Joules to accelerate 20kg to orbital velocity = 156K watt hours And we have 10.4M Wh to work with

76.25meters of runway if you go tail ot nosecone.

Bonus section

I also wanted to use a rockoon to try and win the n-prize

Weather balloon

30ft/1200g 7.6lb nominal lift, 15 lbss max lift. 115,0000 (35,000 m) burst


Cost 124:

Let’s assume that

At 110,000 above sealevel.

Propellant needed to get 10 grams has to less that 6 lbs.

Will it be easier to reach speed because of decreased air density too?


Whole kit for 20ft balloon. 40ft double price but double the list. Burst Altitude: 120,000


How the hell do we know if we got it in orbit? What kind of radio?