Bottom Line: Which launch vehicle would I take if I had to make a choice: The one with a track record of a dozen successful launches, (or maybe even one or two failures in them, but for which the cause has been determined and corrected.) Or the one with just one successful launch?
My choice - the one with the track record. The one with just one sucessful launch may have been very lucky on the first launch. The one with the track record, I know what I'm getting into.
The reason we test software code is because you find more errors in software ( design errors) running the code for two hours than you will in a months worth of code reviews.
Further, I want them to change strategies less often; changing direction costs money.
Agreed. But NASA gets their direction from Congress and since their projects take so long to complete, they don't have a chance to complete one before getting jerked around and forced to head in a new direction by a new Administration.
My opinion - NASA will never again be able to complete the development of a manned launch system.
And if it explodes, it will destroy the entire device.
If you've seen pictures of the Falcon 9 engine mountings, you'll note that between each engine is a metal barrier of approximately 1.5 cm thickness. As these are not part of the thrust structure, or the engines, I'm guessing that the purpose of these is to block fragments from an exploding engine in one compartment from damaging engines in nearby compartments. So I rather doubt that part from a disintegrating turbine or combustion chamber in one engine is going to fly out and damage an engine in the next compartment.
And by the way, while looking at the missile photos it has 9 engines. This is like one of those ancient Russian designs,
Its actually a lot like one of those ancient American designs too, the Saturn I. Eight engines. And, oh, check out the miserable launch record of that one.
Spacex's engines are more efficient than other American hydrocarbon engines, but the Russians are still better than SpaceX. That's to say the Russians have better technology for this type of engine than any Americans. But, Americans have concentrated on building efficient LH/LOX and Solid motors as opposed to RP-1/LOX.
Yes. But what I can't figure out is why NASA thought it needed a heavy lift vehicle just to launch a capsule into LEO or ISS orbit. Wasn't the Ares V supposed to do the heavy lifting for Moon and interplanetary missions?
The idea is to have your man rated launcher be only what is needed to get to the ISS or LEO. The rest of the equipment was to be launched on Ares V. That means the Ares I launched capsule would dock with the command module/space lab needed to carry the astronauts to Moon or Mars. There's no need for a big heavy capsule like the Orion to be launched on Ares I.
An Atlas V/Delta IV/Falcon 9 sized launch system is what was needed. WTF was NASA doing developing things as large as the Ares I and Orion?
So they take a shuttle booster, dress it up and fire it off. Color me underwhelmed.
Quite true. The solid booster even only had four fueled segments instead of the five that would be on the Ares-I. (The top segment was a 'boilerplate')
As far as I can tell, the only things it 'checked out' were the thrust vectoring system and something for controlling oscillations in the booster.
With the $445 million NASA spent just to launch a vehicle with hardly any new active components, SpaceX would have been able to develop and fly a whole new rocket. Heck NASA couldn't even build a launchpad on the money SpaceX used to develop the Falcon 9.
so Iridium have to take the chance that SpaceX can give them a good launch success rate, when they can go to Boeing et al for an established launcher (although still not guaranteed, but having a proven track record is better than not in these things).
Except that ULA (Boeing, Lockheed Martin) wouldn't really be in the running to launch for Iridium even without SpaceX because of cost. Iridium would likely go with a launch on Russian rockets. Inexpensive AND Proven (even moreso than the American launchers).
Also, from what I understand, SpaceX offers a kind of insurance for their launches. With a 10% premium, they'll provide a re-launch if the initial launch fails. Of course that still wouldn't replace the payload if that were to be destroyed on the initial launch attempt. But Iridium has ordered 'extra' satellites from Thales on expectation that not all launches will be successful.
You're right though in noting that SpaceX really doesn't have much track record. I'm guessing that Iridium could back out of the deal if SpaceX's track record for the NASA COTS launches is not good.
The falcon 9 can actually lose 2 engines and make it to orbit ok. But the Saturn V could also make orbit if one of the big F1 engines failed, so long as it didn't fail too early.
They are now United Launch Alliance, for their rockets.
They're priced too expensive for commercial customers. Nearly all of their launches are for the U.S. Government. Commercial launches generally use Russian or Ukranian rockets. From what I've read, there have been about 5 launches with Russian rockets to every 1 launch of an american rocket over the course of the last several decades.
The U.S. govt started the EELV program to upgrade the American rockets in about 1995. The American rockets had fallen behind the Russian in terms of launch success rates and reliability. The Delta IV and the Atlas V are results of this program. They appear to be much more reliable than the rockets they replaced. The Atlas V does though use the RD-180, a Russian made engine on the first stage, much to the dismay of some government officials.
Some in the U.S. complain that after the retirement of the Space Shuttle later this year, the U.S. will not have the capability to launch a manned spacecraft. But when launching using the Russian Soyuz, it's hard to beat their launch costs. I mean, U.S. consumers buy foreign made products all the time because they're cheaper. What's the deal with just buying cheaper, foreing launch services?
What defines proven...
According To Elan Musk, The first three or four launches he considers beta testing, even if some are launched with an actual payload.
Guessing - I'm thinking a battery on the first stage shorted out, causing the battery to burst and the electronics (for guidance, control, and communication) to shut down. This caused the rocket drop power and veer off course (no guidance). Soon after the rocket destabilized, the fuel tanks broke apart and then ignited causing the rocket to explode.
The Koreans don't get the technology, just the use of the rocket. They aren't even allowed to recover the 1st stage of the rocket in order to examine it and determine what failed. They're dependent on the Russians to do that.
Unfortunately the only fully realistic test for a rocket is a launch.
Like testing how the stage separation works in 0 g and testing that the ignition of an engine works in vacuum and at zero g. Tough to duplicate those outside of a real launch.
1 kW/m2, So say we cover 1 square mile with photocells that are 15% efficient. That's about 1580 meters x 1580 Meters x 1KW/m^2 *.15 ~= 375 MW.
That doesn't seem like a lot of area for that much power.
(Forgot to account for latitude, but that shouldn't affect it normally by more that a factor of 1/sqrt(2)).
due to neutrons released in the fusion explosion impacting the lead or uranium nuclei.
which then become unstable radioactive isotopes and then quickly decay, releasing energy, and transform into more stable isotopes.
Yeah. They kind of discovered this by (nuclear) accident.
The trick in learning to do something well is to make your mistakes fast. In other words, expect mistakes. Analyze and learn from the mistake, and quickly move on to the next attempt. And push that attempt as far as you can until you have another problem.
...the Atlas 5 would be a better choice than the Ares 1 for a manned launch vehicle
I agree. NASA didn't really even consider using the Atlas V, because of the Russian Engine. The Head of NASA at the time they decided upon using the 'booster' approach seemed to be really against using any Russian derived technologies in the rocket. This in spite of the fact they made what were arguably the best suitable engines for the first stage of a manned rocket.
They screwed up on the capsule as well. They should have gone more with the Sputnik appoach, with a separate, small, lightweight, section designed specifically for launch and reentry.
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Bottom Line: Which launch vehicle would I take if I had to make a choice: The one with a track record of a dozen successful launches, (or maybe even one or two failures in them, but for which the cause has been determined and corrected.) Or the one with just one successful launch?
My choice - the one with the track record. The one with just one sucessful launch may have been very lucky on the first launch. The one with the track record, I know what I'm getting into.
The reason we test software code is because you find more errors in software ( design errors) running the code for two hours than you will in a months worth of code reviews.
It's great that they can launch a rocket cheaper than NASA can launch a shuttle.
Well nearly any rocket can be launched cheaper than NASA can launch a shuttle, that's not a big deal.
BTW, which one would be the Pinto? The one that burned up on occasion?
Further, I want them to change strategies less often; changing direction costs money.
Agreed. But NASA gets their direction from Congress and since their projects take so long to complete, they don't have a chance to complete one before getting jerked around and forced to head in a new direction by a new Administration.
My opinion - NASA will never again be able to complete the development of a manned launch system.
And if it explodes, it will destroy the entire device.
If you've seen pictures of the Falcon 9 engine mountings, you'll note that between each engine is a metal barrier of approximately 1.5 cm thickness. As these are not part of the thrust structure, or the engines, I'm guessing that the purpose of these is to block fragments from an exploding engine in one compartment from damaging engines in nearby compartments. So I rather doubt that part from a disintegrating turbine or combustion chamber in one engine is going to fly out and damage an engine in the next compartment.
And by the way, while looking at the missile photos it has 9 engines. This is like one of those ancient Russian designs,
Its actually a lot like one of those ancient American designs too, the Saturn I. Eight engines. And, oh, check out the miserable launch record of that one.
NASA doesn't build any spacecraft, they hire contractors.
So basically NASA is a contractor that hires other contractors that hire subcontractors that hire sub-subcontractors....
I think I see the problem here.
Spacex's engines are more efficient than other American hydrocarbon engines, but the Russians are still better than SpaceX. That's to say the Russians have better technology for this type of engine than any Americans. But, Americans have concentrated on building efficient LH/LOX and Solid motors as opposed to RP-1/LOX.
Yes. But what I can't figure out is why NASA thought it needed a heavy lift vehicle just to launch a capsule into LEO or ISS orbit. Wasn't the Ares V supposed to do the heavy lifting for Moon and interplanetary missions?
The idea is to have your man rated launcher be only what is needed to get to the ISS or LEO. The rest of the equipment was to be launched on Ares V. That means the Ares I launched capsule would dock with the command module/space lab needed to carry the astronauts to Moon or Mars. There's no need for a big heavy capsule like the Orion to be launched on Ares I.
An Atlas V/Delta IV/Falcon 9 sized launch system is what was needed. WTF was NASA doing developing things as large as the Ares I and Orion?
So they take a shuttle booster, dress it up and fire it off. Color me underwhelmed.
Quite true. The solid booster even only had four fueled segments instead of the five that would be on the Ares-I. (The top segment was a 'boilerplate') As far as I can tell, the only things it 'checked out' were the thrust vectoring system and something for controlling oscillations in the booster.
With the $445 million NASA spent just to launch a vehicle with hardly any new active components, SpaceX would have been able to develop and fly a whole new rocket. Heck NASA couldn't even build a launchpad on the money SpaceX used to develop the Falcon 9.
so Iridium have to take the chance that SpaceX can give them a good launch success rate, when they can go to Boeing et al for an established launcher (although still not guaranteed, but having a proven track record is better than not in these things).
Except that ULA (Boeing, Lockheed Martin) wouldn't really be in the running to launch for Iridium even without SpaceX because of cost. Iridium would likely go with a launch on Russian rockets. Inexpensive AND Proven (even moreso than the American launchers).
Also, from what I understand, SpaceX offers a kind of insurance for their launches. With a 10% premium, they'll provide a re-launch if the initial launch fails. Of course that still wouldn't replace the payload if that were to be destroyed on the initial launch attempt. But Iridium has ordered 'extra' satellites from Thales on expectation that not all launches will be successful.
You're right though in noting that SpaceX really doesn't have much track record. I'm guessing that Iridium could back out of the deal if SpaceX's track record for the NASA COTS launches is not good.
The falcon 9 can actually lose 2 engines and make it to orbit ok. But the Saturn V could also make orbit if one of the big F1 engines failed, so long as it didn't fail too early.
They are now United Launch Alliance, for their rockets.
They're priced too expensive for commercial customers. Nearly all of their launches are for the U.S. Government. Commercial launches generally use Russian or Ukranian rockets. From what I've read, there have been about 5 launches with Russian rockets to every 1 launch of an american rocket over the course of the last several decades.
The U.S. govt started the EELV program to upgrade the American rockets in about 1995. The American rockets had fallen behind the Russian in terms of launch success rates and reliability. The Delta IV and the Atlas V are results of this program. They appear to be much more reliable than the rockets they replaced. The Atlas V does though use the RD-180, a Russian made engine on the first stage, much to the dismay of some government officials.
Some in the U.S. complain that after the retirement of the Space Shuttle later this year, the U.S. will not have the capability to launch a manned spacecraft. But when launching using the Russian Soyuz, it's hard to beat their launch costs. I mean, U.S. consumers buy foreign made products all the time because they're cheaper. What's the deal with just buying cheaper, foreing launch services?
What defines proven... According To Elan Musk, The first three or four launches he considers beta testing, even if some are launched with an actual payload.
Boeing is basically an engineering firm and contractor these days. Most of the actual work in building a Boeing product is done by other companys.
Guessing - I'm thinking a battery on the first stage shorted out, causing the battery to burst and the electronics (for guidance, control, and communication) to shut down. This caused the rocket drop power and veer off course (no guidance). Soon after the rocket destabilized, the fuel tanks broke apart and then ignited causing the rocket to explode.
The Koreans don't get the technology, just the use of the rocket. They aren't even allowed to recover the 1st stage of the rocket in order to examine it and determine what failed. They're dependent on the Russians to do that.
Unfortunately the only fully realistic test for a rocket is a launch.
Like testing how the stage separation works in 0 g and testing that the ignition of an engine works in vacuum and at zero g. Tough to duplicate those outside of a real launch.
fusion power is aweful
aweful as in awesome or
aweful as in awful?
1 kW/m2, So say we cover 1 square mile with photocells that are 15% efficient. That's about 1580 meters x 1580 Meters x 1KW/m^2 * .15 ~= 375 MW.
That doesn't seem like a lot of area for that much power.
(Forgot to account for latitude, but that shouldn't affect it normally by more that a factor of 1/sqrt(2)).
due to neutrons released in the fusion explosion impacting the lead or uranium nuclei.
which then become unstable radioactive isotopes and then quickly decay, releasing energy, and transform into more stable isotopes. Yeah. They kind of discovered this by (nuclear) accident.
in just 30 years we'll all be using power generated from Fusion. (When have we heard that before?)
The trick in learning to do something well is to make your mistakes fast. In other words, expect mistakes. Analyze and learn from the mistake, and quickly move on to the next attempt. And push that attempt as far as you can until you have another problem.
And the first type of an ICBM's that the U.S. deployed had something like a 50% failure rate on launch.
Actually, you want to make them kind of corkscrw like.
...the Atlas 5 would be a better choice than the Ares 1 for a manned launch vehicle
I agree. NASA didn't really even consider using the Atlas V, because of the Russian Engine. The Head of NASA at the time they decided upon using the 'booster' approach seemed to be really against using any Russian derived technologies in the rocket. This in spite of the fact they made what were arguably the best suitable engines for the first stage of a manned rocket.
They screwed up on the capsule as well. They should have gone more with the Sputnik appoach, with a separate, small, lightweight, section designed specifically for launch and reentry.