QuoteAll design work at the time that had been done on ST Freedom would have had to been scrappedBig problem: ESA and JAXA had been "locked" into the program from the mid-80's. With their Colombus and Kibo modules. That's also the reason why Freedom / Alpha / ISS was never cancelled: don't anger the international partners !
All design work at the time that had been done on ST Freedom would have had to been scrapped
A rather good "myth" buster for this one. As Jim says, the most important lesson learned from the ISS program is "don't bank on an extremely expensive vehicle with potential long standdowns without alternative options for delivery".No matter who the next space station's developer and operator will be, we can be pretty certain the individual pieces will not be much heavier than the current ISS modules.Another thing both Mir and ISS taught is that commonality can pay off and that the Russian approach of docking spacecrafts and modules (each one has its own RCS and attitude control system) is by far easier and cheaper than the "robotic arm does it with many EVAs and a big truss with big solar arrays" approach.
SIGNIFICANTLY while maintaining safety? You don't usually have two dozen people following around SCUBA divers, do you? I know some SCUBA divers who like to go completely solo.
Quote from: Robotbeat on 06/19/2010 06:48 pmSIGNIFICANTLY while maintaining safety? You don't usually have two dozen people following around SCUBA divers, do you? I know some SCUBA divers who like to go completely solo.Hopefully Robonaut helps reduce the hours needed for for EVA. Makes me wonder how much of the Assembly could have been completed with 0 EVA hours if Robonaut had existed 10 years ago.When doing underwater oil work, 2 operators is the absolute minimum you will see underwater together. Some jobs require up to 6 people to be suited up at a time, with only 1-2 person crew working. The others are there for breaks and backup.
modifying the construction program so you don't need a particular vehicle present...
Volume is not as important as mass, in the end mass determines what you can do. whether you're talking about a space station or a colony.
So today, it seems that smaller modules are the way to go, which doesn't appeal to the BFR crowd who insist that over the long run, larger modules have a lower unit cost. That may be readily granted in the discussion, but consider the time for implementation, and their argument fails.
Quote from: JohnFornaro on 06/20/2010 02:33 pmSo today, it seems that smaller modules are the way to go, which doesn't appeal to the BFR crowd who insist that over the long run, larger modules have a lower unit cost. That may be readily granted in the discussion, but consider the time for implementation, and their argument fails.Are there actually any figures on how unit cost compared between Skylab and Mir? For that matter, are there any reliable figures on what the total cost of constructing Mir was? The rough estimates I've found on the internet range between $3B and $4.3B, presumably given in 1980s US dollars.
Russian engineers get paid a lot less than American ones so a Mir to Skylab comparison might not be the best.
We need cheap lift more than we need heavy lift.
As of 2010 "cheap lift" really seems like a pipe dream. And it has been a pipe dream that has been shoved down our throats for almost forty years when were sold the Shuttle.
And exploration could start with existing launchers, so we wouldn't have to wait for the cheap lift to emerge first. In the worst case it will be no more expensive than a dedicated HLV...
Demonstration mission accomplished!
Time is of the essence, then cost.