Author Topic: Falcon Heavy (Read 8490 times)

Hawkmoon · « **Reply #50 on:** February 15, 2018, 11:15:58 PM »

Quote from: Fly320s on February 15, 2018, 10:06:25 PM

No, it would be normal tire pressure (30 psid) reduced by 15 psid before launch so that the final pressure once in space would be back to 30 psid.

10-4

Although the manufacturer's recommended tire pressure for a vehicle weight of essentially zero probably wouldn't be 30 psi.

TommyGunn · « **Reply #51 on:** February 15, 2018, 11:30:06 PM »

Quote from: Fly320s on February 15, 2018, 10:06:25 PM

No, it would be normal tire pressure (30 psid) reduced by 15 psid before launch so that the final pressure once in space would be back to 30 psid.

Why not just leave the tires empty, poke tiny holes in them so the pressure equalizes as the rocket gains altitude, and in the vacuum of space the natural form of the tire will hold it. Or, if it's a flat tire, atleast it's flat on all sides simultaneously.

Perd Hapley · « **Reply #52 on:** February 16, 2018, 12:57:14 AM »

Quote from: TommyGunn on February 15, 2018, 11:30:06 PM

Why not just leave the tires empty, poke tiny holes in them so the pressure equalizes as the rocket gains altitude, and in the vacuum of space the natural form of the tire will hold it. Or, if it's a flat tire, atleast it's flat on all sides simultaneously.

Well, yeah. If you were worried about it, you could drill holes in the inboard side of the tires. You could break the seal between the tires and rims. You could take out the valves. You could replace the tires with solid rubber, or plastic. And on and on...

HeroHog · « **Reply #53 on:** February 16, 2018, 01:20:23 AM »

Simplest route, remove the valve stem core.

HeroHog · « **Reply #54 on:** February 16, 2018, 01:20:56 AM »

and airbags!

mtnbkr · « **Reply #55 on:** February 16, 2018, 07:20:59 AM »

Quote from: HeroHog on February 16, 2018, 01:20:56 AM

and airbags!

Right now some SpaceX engineer is slapping his forehead over the revelation that an unknown internet forum nobody has pointed out something he and his colleagues failed to understand and act upon.

Chris

230RN · « **Reply #56 on:** February 16, 2018, 07:41:47 AM »

Quote from: fistful on February 14, 2018, 01:35:12 AM

One of the comments on the video said it must be fake, because obviously the tires would explode in space, right? Then somebody replied that, duh, it's not some regular car - it's made for a space environment, dummy.

Amazing how these things get started.

Obviously, if you pull the valve cores or otherwise create leak paths, when the tires got up in space, they'd collapse because they'd be full of vacuum.

Fly320s · « **Reply #57 on:** February 16, 2018, 07:46:01 AM »

Quote from: TommyGunn on February 15, 2018, 11:30:06 PM

Why not just leave the tires empty, poke tiny holes in them so the pressure equalizes as the rocket gains altitude, and in the vacuum of space the natural form of the tire will hold it. Or, if it's a flat tire, atleast it's flat on all sides simultaneously.

No, not scientific enough. We must do the maths first and get the right pressure!

230RN · « **Reply #58 on:** February 16, 2018, 07:58:23 AM »

Quote from: Fly320s on February 16, 2018, 07:46:01 AM

No, not scientific enough. We must do the maths first and get the right pressure!

And don't forget to account for the rubber stiffness from the cold....

REF for playtime:

https://www.mide.com/pages/air-pressure-at-altitude-calculator

At 40 kilofeet, ambient pressure is ~2.3 psia, figuring 15Â°F. Was curious about that on them aerioplanes up there and their tires and like that there stuff. FifteenÂ°F was just a plucked out of thin air number. (Pun intended.)

Hawkmoon · « **Reply #59 on:** February 16, 2018, 08:08:51 AM »

Nice little calculator, but doesn't go high enough. Max is 65,000 feet. At 65,000 feet and -40 degrees (it's probably a lot colder in space) the air pressure is 0.33 psi.

230RN · « **Reply #60 on:** February 16, 2018, 08:39:47 AM »

Quote from: Hawkmoon on February 16, 2018, 08:08:51 AM

Nice little calculator, but doesn't go high enough. Max is 65,000 feet. At 65,000 feet and -40 degrees (it's probably a lot colder in space) the air pressure is 0.33 psi.

Yeah, and it's persnickety about the units if you don't set it up right. But 0.02 Bar (0.33 psia) is a pretty good "vacuum," or more correctly, a pretty low pressure.

cordex · « **Reply #61 on:** February 16, 2018, 11:40:15 AM »

My daughters keep asking to watch the video of the launch and booster landings.

MechAg94 · « **Reply #62 on:** February 16, 2018, 11:45:42 AM »

Quote from: cordex on February 16, 2018, 11:40:15 AM

My daughters keep asking to watch the video of the launch and booster landings.

Kids love that stuff. At least I did back in the day. I am glad I was able to visit NASA before they added all the extra security and put a theme park in next door.

makattak · « **Reply #63 on:** February 16, 2018, 11:46:06 AM »

Quote from: cordex on February 16, 2018, 11:40:15 AM

My daughters keep asking to watch the video of the launch and booster landings.

This is seriously one of the most inspiring things of this young century.

Perd Hapley · « **Reply #64 on:** February 16, 2018, 11:47:50 AM »

Quote from: cordex on February 16, 2018, 11:40:15 AM

My daughters keep asking to watch the video of the launch and booster landings.

I bet you make them play with dolls, instead. #patriarchy

just Warren · « **Reply #65 on:** February 16, 2018, 01:15:25 PM »

You've all been lied to! Those tires are not round, they're FLAT!

230RN · « **Reply #66 on:** February 16, 2018, 01:31:00 PM »

Quote from: Warren on February 16, 2018, 01:15:25 PM

You've all been lied to! Those tires are not round, they're FLAT!

Actually, under the launch acceleration they probably do flatten out considerably.

Terry

Perd Hapley · « **Reply #67 on:** February 16, 2018, 09:29:00 PM »

Quote from: Warren on February 16, 2018, 01:15:25 PM

You've all been lied to! Those tires are not round, they're FLAT!

No, they're round. But there HOLLOW!!

just Warren · « **Reply #68 on:** February 16, 2018, 10:04:03 PM »

Quote from: 230RN on February 16, 2018, 01:31:00 PM

Actually, under the launch acceleration they probably do flatten out considerably.

Terry

Don't you dare spacemansplain things!

cordex · « **Reply #69 on:** February 16, 2018, 10:10:44 PM »

Quote from: fistful on February 16, 2018, 11:47:50 AM

I bet you make them play with dolls, instead. #patriarchy

As one does.

Perd Hapley · « **Reply #70 on:** February 17, 2018, 12:26:17 PM »

Quote from: cordex on February 16, 2018, 10:10:44 PM

As one does.

Perd Hapley · « **Reply #71 on:** February 27, 2018, 07:18:05 PM »

sumdood on sum podcast said it cost more to make "The Martian" than it would to go to Mars. Does that sound right to you nerds?

dogmush · « **Reply #72 on:** February 27, 2018, 07:43:32 PM »

Quote from: fistful on February 27, 2018, 07:18:05 PM

sumdood on sum podcast said it cost more to make "The Martian" than it would to go to Mars. Does that sound right to you nerds?

The Martian had a budget of 108 million.

A Falcon Heavy launch with no cargo 90 million.

Not sure you could make a human carrying spaceship that could do life support for a mars trip with 18 million. If it takes a second launch to loft fuel and consumables then definitely not.

Sergeant Bob · « **Reply #73 on:** March 02, 2018, 09:38:36 PM »

Quote from: makattak on February 06, 2018, 04:05:28 PM

Just put Elon Musk's Tesla into Orbit. (And I believe I read it was headed to Mars. I didn't actually listen to the launch, I just watched it.)

http://www.spacex.com/webcast

Wow. https://www.youtube.com/watch?v=wbSwFU6tY1c

Landed both boosters simultaneously, as well. (Not sure what happened to the Core, as the cameras got obscured and, they didn't report before the feed was ended.)

Wow. again.

Wow indeed! The booster landings are truly fascinating!

Sent from my electronical brick via Tap-O-Crap!

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Author Topic: Falcon Heavy (Read 8490 times)