I don't understand the purpose of the low-gain antennas on the MDU. Were they intended to play a role in the cruise phase of the mission, or were the high-gain antennas on the lander supposed to deploy and take over communications? If the LGAs were primarily intended for communications before the deployment of the HGAs, then how could they rationalize the placement of the LGAs where they would be blocked by the auxiliary propellant tank?
I sure hope that the Russians don't think that way. Maybe some of them might hope that an American failure would take attention away from them. But fundamentally, this is not a zero-sum game where one group loses and the other gains. Success helps everybody, and failure hurts everybody.
I sure hope that heads do not roll. That's not the way to improve the organization. The next time the Russians build a planetary mission, it would help if they actually have some people who learned from their mistakes and are paranoid about not repeating them. This is a learning experience, but only if the students don't get expelled.
QuoteI sure hope that heads do not roll. That's not the way to improve the organization. The next time the Russians build a planetary mission, it would help if they actually have some people who learned from their mistakes and are paranoid about not repeating them. This is a learning experience, but only if the students don't get expelled.Agreed, the Russians have shown over and over that this kind of punitive bloodletting is not particularly effective in solving systemic problems. Conversely, NASA has taken the opposite approach with great effect.
My opinion here:Lack of systems engineering. The stack is a kludge, thrown together to save money.
I know this is not possible now but for situations like these it would have been nice to have the Shuttle to go up and grab it and bring it back home, or to fix it in-place.Sure the cost doesn't make sense with the Phobos Grunt mission but in principle that functionality was nice to have (eg. Fix Hubble).
I know this is not possible now but for situations like these it would have been nice to have the Shuttle to go up and grab it and bring it back home, or to fix it in-place.
my post reflected the extreme end of optimism,....... if they are perhaps able to recover the spacecraft but not in time to reach Mars it wouldn't be possible to even consider other missions.
No point in sending a shuttle, the entire probe costs in the region of 160 million dollars including R&D. Making one more should not exceed 50-100 million+launch costs, while a single shuttle flight will cost a lot more.By the way, extremely interesting article about the probe's control and communication system, however it is in Russian and does not describe the final configuration.http://www.novosti-kosmonavtiki.ru/phpBB2/viewtopic.php?t=12378
No point in sending a shuttle, the entire probe costs in the region of 160 million dollars including R&D. Making one more should not exceed 50-100 million+launch costs, while a single shuttle flight will cost a lot more.
some numbers from wikipedia:shuttle cost: approximately $1.5 billion per launch over the life of the programCuriosity: US$2.3 billionPhobos Grunt: $163 millionNASA/ESA joint Mars sample return mission is expected to cost around $8.5 billion
Quote from: iamlucky13 link=topic=15610.msg828128#msg828128 my post reflected the extreme end of optimism,....... if they are perhaps able to recover the spacecraft but not in time to reach Mars it wouldn't be possible to even consider other missions.because your first IF in itself borders on miracle, I separate 'miracle' from optimism, I would never for example say I am optimistic that I could win a lottery ticket where odds are 1:10000000 because IMHO such a statement would sound nonsensical. As to your second assertion spacecrafts are built for a concrete missions, they are highly specialized, and it is mpossible to think how such Phobos- Grunt could be reused in Earth orbit (or any orbit outside of Mars) earthly satellites are considered often a 'total loss' if their orbits are slightly off (insurance covers total amount) and PG would still be a junk even if you managed to turn on it's cameras or instruments, I am running out of breath....
Plus, you really don't want to bring back fully fueled spacecraft if you could help it. What would happen if it started back up again during ops?Non-starter.
Quote from: robertross on 11/11/2011 05:44 pm Plus, you really don't want to bring back fully fueled spacecraft if you could help it. What would happen if it started back up again during ops?Non-starter.Not necessarily. First of all, you would not have to bring the spacecraft back. Simply find a way to charge the battery or bring up more. Then you could load a patch right at the spacecraft. Very similar to the Intelsat/STS-49 mission where the kick stage did not fire, so it was replaced.
May I remind you of what happened to Arabsat-4M Briz-M. For that reason alone placing lives near a fully loaded upper stage like that is a non-starter! You can not bring the risk to zero! Correct me if I am wrong but the Intelsat on STS-49 was a mono-prop system with a solid upper stage. Apples and oranges.
Shuttle was going to launch with a Centaur hydrolox in the payload bay, which would have been much riskier.