"lapzilla" wrote in message news:AqGmb.2439$2o2.18102@amstwist00...
Hi!
I have been following space related stuff since the 60's.
It seems to me to look like russian spacelaunch vehicles accelerate faster
than the big american launch rockets.

Not necessarily. Soyuz FG and Proton have initial thrust/weight
(T/W) ratios in the 1.3 to 1.4 range. It is true that Atlas V/401
and Delta IVM both crawl off their pads with T/W of about 1.2, but
most U.S. launchers use strap-on solid rocket motors, which produce
optimum results at higher T/W. For example, Delta 7920 has T/W
of about 1.56.

I wonder if there is any significant scientific or technical difference in
the way the russians and the americans go about when they launch manned
spaceflights(and other flights)?

IMO, the Russians have the U.S. (and everyone else) beat in
several ways. First, their rockets use straightforward,
standardized designs. For example, Soyuz TMA-3, launched last
week, used the 1,683rd R-7 rocket. The first two stages of that
vehicle have changed little from Korolev's original 1957 design.
About a dozen different R-7 based variants have flown. The
design is undisputedly sound - only 96 R-7 based launches
have failed over the years (and many of the failures involved
upper stages, not the R-7 vehicle itself).

In contrast, the most-often-used U.S. launcher is the Thor-Delta
series, which has flown only 678 times altogether, with about 88
failures (including suborbital IRBM tests and Japanese-licensed
launches). Amazingly, at least 89 different Thor-based
configurations have flown (by my rough count). Not suprisingly,
the most oft-flown configuration (Delta II) has been the most
successful.

Second, the Russians use streamlined launch processing techniques
that are matched only by NPO Yuzhoye's Ukrainian Zenit. Their
launchers don't use hazardous strap-on solid rocket motors,
allowing them to be assembled and checked out horizontally on a
railcar transporter. Soyuz is transported to its pad only two
days before launch. Proton, a Saturn IB sized powerhouse rocket,
is on its pad only one or two days more than Soyuz. (Zenit can
be erected only hours before launch - that is why it was able to
be adapted for Sea Launch use).

Although the new U.S. EELV and European Ariane 5 launchers use
improved launch processing techniques, both are still hamstrung
by solid rocket hazards (which, as Alcantara reminded everyone
recently, are all too real). Delta IV will still need 2-3 weeks
on the pad before launch. Atlas V and Ariane 5 both move to the
pad just before launch, but since both use solid motors, their
vertical integration requires them to occupy their mobile launch
platforms for weeks (unlike Soyuz, which is actually lifted onto
its launch/transport platform only a few days before launch.)

Russia's rockets have proven themselves again this year. Soyuz
provided the only access to ISS while Proton quietly wrested
control of the commercial launch market, winning more launch
contracts than Arianespace this year.

I think the world has much to learn from the Russians, who are,
after all, the world's most experienced spacefarers.

- Ed Kyle