New Gagarin flight details

Pat Flannery writes:

The retro burn itself wasn't nominal, and ended when the engine ran out
of fuel, rather than when it had slowed the spacecraft the desired
amount. It ended up with five kilometers per second speed over what was
intended, and spinning rapidly on its axis.

If this engine had slowed the craft five km/s more if it had worked as
intended it must have been a miracle engine.


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery

Interesting article on what really happened during Gagarin's flight:
http://www.russianspaceweb.com/vostok1.html
Interesting facts - the "CCCP" was painted on his helmet at the last
minute to make sure he wouldn't be mistaken for a downed U-2 pilot.
The footage of the Vostok launch that is shown nowadays is actually of
the ill-fated Vostok prototype launch of July 28, 1960, in which two
dogs were killed when the booster blew up.
The capsule entered an orbit that had an apogee that was nearly 100km
high - this meant that if the retro engine failed,it didn't have enough
life support aboard to allow Gagarin to survive until it descended via
atmospheric decay (two weeks).
It also meant that the orbital period that was longer than desired, and
the timer that fired the retro caused it to come down 300 km short of
the intended recovery area.
The retro burn itself wasn't nominal, and ended when the engine ran out
of fuel, rather than when it had slowed the spacecraft the desired
amount. It ended up with five kilometers per second speed over what was
intended, and spinning rapidly on its axis.
The umbilical plug not separating from the reentry sphere understates
the problem; the entire equipment module didn't detach when it was
supposed to, and came off ten minutes late.
As Gagarin descended under his parachute, his reserve chute also
deployed, so he came down under two chutes nice slow descent but an
invitation to chute tangling and a fatal fall.
So that flight went far from smoothly, with plenty of cliff-hanger moments.

On 4/17/2011 1:43 PM, Jochem Huhmann wrote:
Pat writes:

The retro burn itself wasn't nominal, and ended when the engine ran out
of fuel, rather than when it had slowed the spacecraft the desired
amount. It ended up with five kilometers per second speed over what was
intended, and spinning rapidly on its axis.

If this engine had slowed the craft five km/s more if it had worked as
intended it must have been a miracle engine.

Whoops, little slip there...should be five _meters_ per second.

Pat