In article ,
says...

On 2018-10-12 15:18, Fred J. McCall wrote:

I know you can never be bothered to look things up before you make
ignorant statements, but you should read the Falcon 9 payload
integration document.

I doubt NASA would consider a crewed capsule to be a mere payload on a
otherwise automated rocket.

You're wrong. There is a lot of monitoring of what is happening with
the launch vehicle and anything critical automatically triggers the
abort system. Some catastrophic failures happen so fast that this is
the only way to trigger the abort system fast enough. Putting a person
in the loop would not help at all.

There has to be far more sophisticated command/control channels between
crew module and stage 1 and stage 2 than for a cargo flight.

Nope. Either the flight control system gets the capsule to earth orbit
or the capsule aborts. There is very little middle ground here. The
only middle ground is something like a first stage engine failure which
causes that stage to abort its recovery attempt and use its remaining
fuel to get the second stage to where it needs to go. This happened on
one Dragon flight and it still got to ISS. However the secondary
payloads didn't make it to their intended orbits.

And that would mean software on stage 1 and 2 would need to have the
ability to send and receive far greater range of packet types on what
might be an existing data bus. (or perhaps crewed Fancons will have
extra data bus going to capsule).

Dragon 2 might be used to store telemetry data, but I doubt that it
commands the launch vehicle in any way. Dragon is just another payload.
You don't want it to be "special" or you open up the possibility that
what makes it "special" will cause a launch failure.

Why would you expect that? What is the crew going to do?

If the capsule has the ability to automatically command an eject, then
that capsule must be getting a whole bunch of telemetry from the stages
below it to make the decision.

Not necessarily. The simplest solution is that the flight control
computer on the Falcon 9 sends a single ABORT signal to the Dragon 2.
The Dragon 2 doesn't care why it's aborting, it just needs to GO!

In an eject, do the fairings have to go out first? Won't the capsule
have to have authority to command fairing ejection?
snip

There are no fairings on a Dragon or Dragon 2 flight. The Dragon or
Dragon 2 is the "nose cone" and is exposed to the atmosphere on all
sides except aft, where its trunk attaches to the Falcon 9.

That was hardly the only thing they found. Go read the report.

The Columbia destruction was caused by foam that hit RCC panels on
leading edge of wing. They found this very quickly. That was the cause
of loss of vehicle.

The board, in making its inquiry found many other things wrong even if
they weren't involved in the loss of Columbia per say.

This is true. Note that they found actual hardware issues that
engineers needed to fix.

Many of the
problems were with NASA culture and not the Shuttle.

This is sort of true. NASA didn't bother planning for a shuttle
stranded in orbit. After Columbia there not only was a plan, but actual
changes in how the program was executed.

The Russians may not do in-depth investigations such as with Challenger
and Columbia but that doesn't mean they don't find the actual cause of a
failure quickly and if tyey are confident the problem isn't present in
the next Soyuz, they will launch quickly since they can check for it.

I'd argue they will find the singular cause of this incident and address
it. But they'll ignore any and all other problems in order to fly again
quickly. NASA has had groundings that lasted a couple years. Russia's
Soyuz isn't really grounded. They plan on launching in December, which
was the original plan all along.

They're not fixing the bigger problem of lax quality control. Vehicles
which have heritage back to the 1960s shouldn't randomly fail like they
have been for Russia.

It is when you have a problem where you are not sure why it happened, or
how to fix it that you have to suspend flights for a long time.

This is how the Russian space program thinks. Unfortunately, this sort
of thinking is what eventually gets people killed.

Jeff
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