AWST Delta IV-H Failure Cause?

Aviation Week's on-line site has a headline
this week something along the lines of:
"Delta IV-Heavy Succeeds but Software Needs
Work".

Is AvWeek reporting a flight control issue as
the cause of the early RS-68 booster shutdown?

- Ed Kyle

Ed Kyle wrote:
Aviation Week's on-line site has a headline
this week something along the lines of:
"Delta IV-Heavy Succeeds but Software Needs
Work".

Is AvWeek reporting a flight control issue as
the cause of the early RS-68 booster shutdown?

Yes. The article states:
"The Rocketdyne/Boeing new RS-68 first-stage engines are not suspect,
but rather the closed-loop software timing and performance measurement
systems controlling them. "It's not yet clear what the root cause is"
of the timing problem, Collins told Aviation Week & Space Technology."

And along the lines of the earlier succeed/fail discussion:
"BOTH BOEING and the Air Force say a relatively simple software fix
should correct the problem. Plans for a second launch in August
carrying a Defense Support Program missile warning satellite remain on
track, both organizations assert. "

Lou Scheffer

On 2 Jan 2005 19:25:35 -0800, in a place far, far away, "Ed Kyle"
made the phosphor on my monitor glow in such a
way as to indicate that:

Aviation Week's on-line site has a headline
this week something along the lines of:
"Delta IV-Heavy Succeeds but Software Needs
Work".

Is AvWeek reporting a flight control issue as
the cause of the early RS-68 booster shutdown?

Sounds like it to me.

wrote:
Ed Kyle wrote:

Is AvWeek reporting a flight control issue as
the cause of the early RS-68 booster shutdown?

Yes. The article states:
"The Rocketdyne/Boeing new RS-68 first-stage engines are not suspect,
but rather the closed-loop software timing and performance
measurement
systems controlling them. "It's not yet clear what the root cause is"
of the timing problem, Collins told Aviation Week & Space
Technology."

And along the lines of the earlier succeed/fail discussion:
"BOTH BOEING and the Air Force say a relatively simple software fix
should correct the problem. Plans for a second launch in August
carrying a Defense Support Program missile warning satellite remain
on
track, both organizations assert. "


If they don't know the root cause, how can they say
that the fix is "simple" and that the problem is
"software"?

- Ed Kyle

Ed Kyle wrote:
wrote:

Yes. The Av Week article states:
"The Rocketdyne/Boeing new RS-68 first-stage engines are not
suspect,
[...] "It's not yet clear what the root cause is"
of the timing problem, Collins told Aviation Week & Space
Technology."

And along the lines of the earlier succeed/fail discussion:
"BOTH BOEING and the Air Force say a relatively simple software fix
should correct the problem. "

If they don't know the root cause, how can they say
that the fix is "simple" and that the problem is
"software"?

That's a very good question. My guess is that they know there was
plenty of fuel there, and the engines were running fine, and they
probably know that the software shut down the engines prematurely.
It's not at all clear to me why they can't find the root cause, though,
if this is the case. Presumably they telemeter down all the pressure,
temperature, fuel level, INS, etc., readings the computer sees. Given
that, if they cannot reproduce the software's behavior, something is
very wrong.

Lou Scheffer

Ed Kyle wrote:
Aviation Week's on-line site has a headline
this week something along the lines of:
"Delta IV-Heavy Succeeds but Software Needs
Work".

Is AvWeek reporting a flight control issue as
the cause of the early RS-68 booster shutdown?

I hate the idea that software problems are not as serious
as hardware problems. Software is serious business, and
when the successful operation of a machine relies on it the
consequences of its failure are just as serious as for any
other component. Your car is no less dead if the ECM
malfunctions than if the carburetor jams, broken is broken,
sofware or no.

"Christopher M. Jones" wrote in
:

Ed Kyle wrote:
Aviation Week's on-line site has a headline
this week something along the lines of:
"Delta IV-Heavy Succeeds but Software Needs
Work".

Is AvWeek reporting a flight control issue as
the cause of the early RS-68 booster shutdown?

I hate the idea that software problems are not as serious
as hardware problems. Software is serious business, and
when the successful operation of a machine relies on it the
consequences of its failure are just as serious as for any
other component. Your car is no less dead if the ECM
malfunctions than if the carburetor jams, broken is broken,
sofware or no.


An engine design flaw might require a couple of years of
investigation, fabrication and testing to requalify the
engine. One hopes that software is a bit easier to fix.

But yes, software is a very real part of the vehicle, as
Ariane V demonstrated on its first flight.

--Damon

The Delta IV team returns to work tomorrow after a well deserved 11
day break. So tomorrow the telemetry data will start to be analized
and the results peer reviewed.

*-----------------------*
Posted at:
www.GroupSrv.com
*-----------------------*

"Hyperflow" wrote in message
...
The Delta IV team returns to work tomorrow after a well deserved 11
day break. So tomorrow the telemetry data will start to be analized

Sounds painful.


and the results peer reviewed.

I assume on goats.cx....



*-----------------------*
Posted at:
www.GroupSrv.com
*-----------------------*

Hyperflow wrote:
The Delta IV team returns to work tomorrow after a well deserved 11
day break. So tomorrow the telemetry data will start to be analized
and the results peer reviewed.

This seems crazy to me from a personality-of-engineers point of view.
You sweat for years to get this sucker off the ground, it's your
personal and professional goal for a good fraction of your working
life, it damn near fails, then you go on vacation and don't even look
at the telemetry???

If I was the guy who wrote, or spec'ed, or managed that software, I'd
be intensely curious about the failure, in addition to an enormous
sense of professional responsibility to understand and correct the
mistake, if it was indeed mine. If you care, really care, about the
quality of what you produce, I don't see how you could possibly relax
during your vacation without at least basic understanding of the
problem, and some visibility into the fix.

The peer review, detailed analysis, and corrective action can indeed
wait until after the vacation, and I hope that is what was meant. But
if the responsible person wasn't in there the day after the flight, and
until the problem was basically understood, there is something very
wrong. Pride in your work, and a deep-seated need for understanding,
should be basic to this job, or indeed any engineering job.
Lou Scheffer