"It's interesting to see how the Russians do upgrades to the Soyuz spacecraft"
Yes, it's interesting looking at the differences between how the US and Russia develop their vehicles for their respective space programmes.
The Americans seem to have gone for complex, expensive, brand new designs from the ground up, which they then risk-assess the hell out of (in theory at least.)
The Russians, on the other hand, build something that they have some prior experience of, which is usually fairly simple, very effective, and only moderately dangerous. In testing it'll go bang, they'll work out why it went bang, fix it, and test it again. Then rinse and repeat. When the design stops going bang, you end up with a very effective, reliable piece of kit, which is why Russian rocket engines have been used in some US space vehicles since the end of the cold war - they're only starting to get unreliable now (see Orbital Sciences) due to age and poor maintenance.
It does look as if the US have learnt something from the Russian design process though - their latest heavy lifter, the SLS, will re-use slightly updated versions of the Shuttle main engines and SRBs - why design something totally new when you've already got thoroughly tested, improved and reliable kit (now that the SRB O-ring leaks have been fixed.)
Biting the hand that feeds IT
