Space Cannon: Groobles incredible dream

[rocketman5000]

Mr. Lorry can not reply to you....

 

[gunsandrockets]

"Mr. Lorry can not reply to you.... "<br /><br />Here's why...<br /><br />5/9/2006 - User mlorrey banned for multiple violations, ignoring Moderator instructions, disruptive postings. Ban permanent.

 

[qso1]

Seems to me the idea of using a cannon or gun to fire payloads into space is because its less expensive to do than current rockets. Yet looking at mlorreys comment a few posts back, talkning about scramjet second stage and scramrocket third stage. Scramjet and scram rocket techology are still not operational anywhere in the world largely due to the expense of bringing them about.<br /><br />Even using just a conventional rocket second stage in conjunction with the cannon begs the question...why not stick to the same type of system for all stages? This is what we do today probably because despite its still relatively high expense, chemical rockets are the least expensive solution to the problem of getting payloads to orbit.<br /><br />If Nexiums idea proves out, carbon nanotube barrels that is. Then maybe the cannon as a launcher will be cost effective. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[docm]

IMO a chemical gun as a spacecraft weapon makes little sense because of the recoil of a large enough weapon to have internal guidance that can withstand the 10,000+ G's of firing. This is only now small enough to fit in artillery shells. <br /><br />A rocket launcher makes more sense if launch tubes (think bazooka/Dragon etc.) are used as the reaction/counter-reaction nearly equalize any torque applied to the spaceship. About all that's left is the friction between the rocket and tube providing a bit of torque, and that could be corrected for numerous ways.<br /><br />Also, in space very small diameter but long burning rockets would do given adequate guidance systems; IR + radar + lidar. Small diameter translates into more shots/pack.<br /><br />OTOH in a spacecraft with nuclear power for a VASIMR or other plasma drive rail guns would be a natural. <br /><br />The NAVY already has them on the boards for the upcoming next-gen destroyers and carriers and a light projectile weight should be more than enough to blast spacecraft hulls. Not much need for guidance at their speeds & at closer ranges. I would also think the launcher need not be as large for spacecraft as it would for shipboard use either. <br /><br />Then there's always directed energy weapons. <div class="Discussion_UserSignature"> </div>

 

[qso1]

The gun as a launcher makes little sense to me as well, but mainly on economic grounds due to having to use rocket upper stages to attain orbit. If a projectile could reach orbit from a gun or cannon, it would not only have to endure tremendous "G" loads, but friction with the thick lower atmosphere it has to go through to reach orbit. And keeping in mind the payload won't reach orbit going vertical. The gun would have to fire at a low angle to facilitate proper entry into earth orbit which means more time spent in the lower atmosphere. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[nexium]

Since the gun can lobe gigaton H bombs on targets thousands of kilometers away, the gun will be a prime target for most any enemy, including terrorists. A large second stage will be required to reach orbit.<br />If we invent a scram jet 2nd stage, a 3d stage scram rocket or at least an ion engine will be needed for anywhere in the Solar system including Earth orbit. A bolo = rotovator might compliment such a big gun. As much as a two meter bore may be necessary for orbit. NASA won't want the monster anywhere near it's launch facilities, as the barrel could split open. A trillion dollar launch facillity including most everything will be needed as no one will want the big gun near where they live. Can you imagine the cost of putting it at the top of Mt. Mckinley in Alaska?<br />If the average accelleration of the projectile is 4000 meters per sec per sec = 410 g for 1 second; s = 1/2 at squared = 2000 times 1 = 2000 meters of barrel; v= at = 4000 times 1 = 4000 meters per second = 4 kmps, which may not be fast enough to start a scram jet. We may need to more than 410 g and pray the barrel does not burst, or split. Neil

 

[publiusr]

It is an interesting concept. Good for raw materials and such.