Author Topic: Boeing's CST-100 - Master Updates and Discussion Thread 3  (Read 236235 times)

Offline whitelancer64

*snip*

I thought the capsule should be passively stable? Or is that just Soyuz?

Starliner's center of gravity must be close to its center of pressure.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline edzieba

  • Virtual Realist
  • Full Member
  • ***
  • Posts: 385
  • United Kingdom
  • Liked: 404
  • Likes Given: 30
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #381 on: 07/25/2018 05:07 pm »
I thought the capsule should be passively stable? Or is that just Soyuz?
IIRC, sphere-section RVs like CST-100 (and Dragon, and Orion, and Apollo...) are passively stable when entering in the correct heatshield-down orientation. If they start entry in the wrong orientation, they tumble.
Vostok & Voskhod had spherical RVs so could being entry at any orientation and stabilise just through mass distribution (albeit in a manner somewhat unpleasant to the occupants). The Soyuz RV I'm less sure on, past incidents (e.g. the Service Module failing to detach resulting in a reversed re-entry orientation until the heating caused separation through strut failure) indicate it is able to passively re-orient during re-entry.

Online Olaf

  • Full Member
  • ****
  • Posts: 1897
  • Germany
  • Liked: 616
  • Likes Given: 243
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #382 on: 07/26/2018 06:41 pm »
https://twitter.com/jeff_foust/status/1022534491926159361
Quote
Nield: Boeing has asked for more time to understand impacts of abort hot-fire test anomaly. Expect some uncertainty in their near-term schedule while they go through that.
https://twitter.com/SciGuySpace/status/1022534584301486080
Quote
ASAP's George Nield on recent Boeing anomaly during hot-fire test of abort engines. "We need to better understand it in terms of its potential impact on design, operations and schedule. Boeing has asked for some additional time" to study the issue.

Online docmordrid

  • Senior Member
  • *****
  • Posts: 5330
  • Michigan
  • Liked: 2632
  • Likes Given: 1
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #383 on: 07/27/2018 01:12 am »
That does not sound like a test stand problem.
DM

Offline erioladastra

  • Full Member
  • ****
  • Posts: 1289
  • Liked: 87
  • Likes Given: 0
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #384 on: 07/28/2018 06:58 pm »
https://twitter.com/BoeingSpace/status/1021761282377113600
Quote
An exciting day for the entire #Starliner and @BoeingSpace team! Let's get ready to fly! Learn more about #Boeing test pilot @Astro_Ferg via @washingtonpost and @wapodavenport.
https://www.washingtonpost.com/news/business/wp/2018/07/24/feature/nasa-trained-boeing-employed-chris-ferguson-hopes-to-make-history-as-a-company-astronaut/?utm_term=.90f444a53789

What happens if NASA uses CFT to do crew rotation? Does Ferguson get kicked off the mission, or does he get to stay on ISS for 6 months?

Also I'm confused about this part:
Quote
The shuttle had wings, like a plane. His new spacecraft was a thimble-shaped capsule, far more difficult to control. In this particular test, he’d be facing a worst-case scenario: Every computer of the autonomous spacecraft would be out, meaning he’d have to fly it manually, hitting the atmosphere at Mach 25, or 25 times the speed of sound, then, somehow, bring it down for a soft landing. Two of the four NASA astronauts who had attempted it had failed, losing control of the spacecraft so that it tumbled, and Ferguson was eager to get in some extra practice.

I thought the capsule should be passively stable? Or is that just Soyuz?

 trying to fly the thing with the computers "out" is a waste of time...

there is no realistic possibility of this occurring

no realistic possibility of the computers failing or flying without?   I think Ferguson just told you that it works about 50% of the time - and that was early during assessments when it was being tested.  Now hopefully it will never be needed because it will always be risky no matter how good the crew get.

Offline TripleSeven

  • Full Member
  • ****
  • Posts: 761
  • Istanbul turkey
  • Liked: 322
  • Likes Given: 1381
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #385 on: 07/28/2018 07:32 pm »
https://twitter.com/BoeingSpace/status/1021761282377113600
Quote
An exciting day for the entire #Starliner and @BoeingSpace team! Let's get ready to fly! Learn more about #Boeing test pilot @Astro_Ferg via @washingtonpost and @wapodavenport.
https://www.washingtonpost.com/news/business/wp/2018/07/24/feature/nasa-trained-boeing-employed-chris-ferguson-hopes-to-make-history-as-a-company-astronaut/?utm_term=.90f444a53789

What happens if NASA uses CFT to do crew rotation? Does Ferguson get kicked off the mission, or does he get to stay on ISS for 6 months?

Also I'm confused about this part:
Quote
The shuttle had wings, like a plane. His new spacecraft was a thimble-shaped capsule, far more difficult to control. In this particular test, hed be facing a worst-case scenario: Every computer of the autonomous spacecraft would be out, meaning hed have to fly it manually, hitting the atmosphere at Mach 25, or 25 times the speed of sound, then, somehow, bring it down for a soft landing. Two of the four NASA astronauts who had attempted it had failed, losing control of the spacecraft so that it tumbled, and Ferguson was eager to get in some extra practice.

I thought the capsule should be passively stable? Or is that just Soyuz?

 trying to fly the thing with the computers "out" is a waste of time...

there is no realistic possibility of this occurring

no realistic possibility of the computers failing or flying without?   I think Ferguson just told you that it works about 50% of the time - and that was early during assessments when it was being tested.  Now hopefully it will never be needed because it will always be risky no matter how good the crew get.

both...there is no realistic chance of the computers failing...and flying the thing without them would be a massive training undertaking AND the latency of this would be very short lived.

I'll give you a "non" computer example of what has no realistic chance of happening and would be very very difficult to accomplish in any event

the Boeing 737 is not a fly by wire airplane.  it does however have on the flight control system hydraulics redundancy that is about the same as the redundancy in computers and power sources, in a fly by wire airplane

IF all the hydraulics fail there is still a way to fly the airplane, it is called manual reversion...ie you fly the jet much like they flew the B17 and B29 in WW2 (and later). 

IF one has time in initial training and if one has time in recurrent training...one demonstrates this mode.  Its never happened IN ALL the flight time of the airplane...

but 1) it is not evaluated and 2) not something that the training last long for, meaning six months latter in Captains recurrent training the same problems that you had to train the first time have come back

but what this would be the equivelent to is manual reversion in the B737 and an engine failure at the same time

when I was in that airplane and instructing checking in it, and a test pilot in it... we use to "do this" when we had spare simulator time.  if I went to Dallas, chicago, LA Atlanta, pulled a B737 pilot at random and put him/her in the simulator and tried that...there is near zero chance they could accomplish it

its "possible" to happen, its very unlikely.  very very unlikely. 

its just test pilots playing.  we do that
« Last Edit: 07/28/2018 07:33 pm by TripleSeven »

Offline JAFO

  • Full Member
  • ****
  • Posts: 629
  • Liked: 278
  • Likes Given: 204
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #386 on: 07/29/2018 03:54 am »
United 232. Ive never known a good pilot who said they were overtrained.




Thread being trimmed in 3.. 2..




  ;D
« Last Edit: 07/29/2018 03:55 am by JAFO »
Anyone can do the job when things are going right. In this business we play for keeps.
Ernest K. Gann

Offline rayleighscatter

  • Full Member
  • ****
  • Posts: 1045
  • Maryland
  • Liked: 487
  • Likes Given: 230
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #387 on: 07/29/2018 02:02 pm »

both...there is no realistic chance of the computers failing...

Shuttle had a computer failure on its very first ALT flight.

Offline TripleSeven

  • Full Member
  • ****
  • Posts: 761
  • Istanbul turkey
  • Liked: 322
  • Likes Given: 1381
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #388 on: 07/29/2018 02:34 pm »

both...there is no realistic chance of the computers failing...

Shuttle had a computer failure on its very first ALT flight.

computers fail "not frequently but a failure is not impossible" that is why in my plane there are four of them :) anyone can fly the plane

Offline TripleSeven

  • Full Member
  • ****
  • Posts: 761
  • Istanbul turkey
  • Liked: 322
  • Likes Given: 1381
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #389 on: 07/29/2018 02:57 pm »
United 232. Ive never known a good pilot who said they were overtrained.









  ;D
Training is a cost center.  it takes time and money to train everyone...the more you train the higher the cost, the more you train things that are extremely unlikely to happen, the higher the cost the longer the time. 

if you want to make money or actually be operational with "things" that are trained, you have to make coherent decisions trading off the two and then depend on the "latent" capabilities when things go really bad. 

I have some idea of what Boeing thinks that they can get the eventual "training time" and cost per person down to on the starliner, no Idea what SpaceX thinks but I am sure its about the same.  if space ops cost and tempo are going to go down and up  (respectively)  training cost will be a big part of that.  For reference the average US airline right now spends  (not counting LIFUS) about 50,000 dollars to train a new Captain in anyBoeing. 

Al Haynes and the rest of the crew and passengers on the flight were extremely lucky.  UAL has the same thing my airline has, they are called technical pilots.  and then there are technical pilot/instructors.  all technical pilots at UAL (and my shop) are were test pilots.  the ones who can instrust are also made instructors

 one of UAL's DC 10 technical pilot instructors was on the flight with his family.  he had in his spare time what we call "dick around" with the issue before them.  it had never happened before or since in the DC-10 :)

the only real "similar" spaceflight accident to the UAL flight was the ops on Apollo 13 where the lunar module engine was used to change the vectors of the entire stack  I dont think (someone can correct me) that they had ever simmed that.  Dan B's flying on the Intelsat rescue mission was unique but really was just a tour de force in precision flying.  (which he was one of the best at)

(I am lucky in my job..about every week me and a partner can get two hours of so in the box to do whatever we want to try...we do try pretty strange things)

three two one :) safe flights

Offline erioladastra

  • Full Member
  • ****
  • Posts: 1289
  • Liked: 87
  • Likes Given: 0
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #390 on: 07/30/2018 02:15 pm »


both...there is no realistic chance of the computers failing...and flying the thing without them would be a massive training undertaking AND the latency of this would be very short lived.

I'll give you a "non" computer example of what has no realistic chance of happening and would be very very difficult to accomplish in any event

the Boeing 737 is not a fly by wire airplane.  it does however have on the flight control system hydraulics redundancy that is about the same as the redundancy in computers and power sources, in a fly by wire airplane

IF all the hydraulics fail there is still a way to fly the airplane, it is called manual reversion...ie you fly the jet much like they flew the B17 and B29 in WW2 (and later). 

IF one has time in initial training and if one has time in recurrent training...one demonstrates this mode.  Its never happened IN ALL the flight time of the airplane...

but 1) it is not evaluated and 2) not something that the training last long for, meaning six months latter in Captains recurrent training the same problems that you had to train the first time have come back

but what this would be the equivelent to is manual reversion in the B737 and an engine failure at the same time

when I was in that airplane and instructing checking in it, and a test pilot in it... we use to "do this" when we had spare simulator time.  if I went to Dallas, chicago, LA Atlanta, pulled a B737 pilot at random and put him/her in the simulator and tried that...there is near zero chance they could accomplish it

its "possible" to happen, its very unlikely.  very very unlikely. 

its just test pilots playing.  we do that

Actually, there is a small, non-zero chance of the computers failing.  In fact, twice in the life of the ISS we have already seen three cases where the triple-redundant command and control computers have failed - one case was d3 different hardware failures ("can't ever happen" they said), one was a software issue and one was an environment issue.  In the case of an aircraft you have the luxury of thousands and thousand and thousands of hours testing and flying the software that you won't get with a single spacecraft system.  So a chance of a software issue is much higher - even if the hardware has already been shown to be pretty robust.  NASA already did a bunch of assessment runs to see how things performed.  Some level of manual flying will be developed because psychologically the astronauts will drive it.  But as you note, not massively trained because that is a huge expense for minimal benefit.

Offline erioladastra

  • Full Member
  • ****
  • Posts: 1289
  • Liked: 87
  • Likes Given: 0
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #391 on: 07/30/2018 02:16 pm »
United 232. Ive never known a good pilot who said they were overtrained.









  ;D
Training is a cost center.  it takes time and money to train everyone...the more you train the higher the cost, the more you train things that are extremely unlikely to happen, the higher the cost the longer the time. 

if you want to make money or actually be operational with "things" that are trained, you have to make coherent decisions trading off the two and then depend on the "latent" capabilities when things go really bad. 

I have some idea of what Boeing thinks that they can get the eventual "training time" and cost per person down to on the starliner, no Idea what SpaceX thinks but I am sure its about the same.  if space ops cost and tempo are going to go down and up  (respectively)  training cost will be a big part of that.  For reference the average US airline right now spends  (not counting LIFUS) about 50,000 dollars to train a new Captain in anyBoeing. 

Al Haynes and the rest of the crew and passengers on the flight were extremely lucky.  UAL has the same thing my airline has, they are called technical pilots.  and then there are technical pilot/instructors.  all technical pilots at UAL (and my shop) are were test pilots.  the ones who can instrust are also made instructors

 one of UAL's DC 10 technical pilot instructors was on the flight with his family.  he had in his spare time what we call "dick around" with the issue before them.  it had never happened before or since in the DC-10 :)

the only real "similar" spaceflight accident to the UAL flight was the ops on Apollo 13 where the lunar module engine was used to change the vectors of the entire stack  I dont think (someone can correct me) that they had ever simmed that.  Dan B's flying on the Intelsat rescue mission was unique but really was just a tour de force in precision flying.  (which he was one of the best at)

(I am lucky in my job..about every week me and a partner can get two hours of so in the box to do whatever we want to try...we do try pretty strange things)

three two one :) safe flights

Ahhh, but you assume that Boeing drives that.  NASA will drive what will ultimately me trained.  yeah, Boeing will charge more for it but NASA is not looking to find a cheap way of doing but instead will do it "the right way".  Yeah, I know...

Online Chris Bergin

My current take home is the ASAP's use. Years ago they used to be a bit moany/nitpicky (Shuttle extension, early SpaceX days), but they really are showing their value over recent years.

Commercial companies (rightly to a point) do not want to anything out there unless it's fluffy PR - like the stuff they are paying Politico and PR companies to do. They hate bad news, per their image, but it doesn't matter how much some of them (Boeing Starliner) ignore media requests you always have the safety net of honest official information from the likes of the ASAP that show it will eventually get out there. Hopefully, the knowledge of that will make them realize it's in their interests to answer questions.

But I do get it. Even if a site like ours had info of an issue. We (as we do) took the correct route to ask them for clarification. We wrote a good article, a fair one, with answers.... some mass media clickbait style site would take our article, make it dramatic, and then Boeing would have wished they never picked up the initial request.

It's a minefield out there. But the ASAP meeting shows even if they don't answer, the ASAP won't be held to the same restrictions. They get answers and they put it out there in public.

Online ncb1397

  • Full Member
  • ****
  • Posts: 1305
  • Liked: 569
  • Likes Given: 6
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #393 on: 07/30/2018 02:47 pm »
Learning to fly the craft manually is not a waste of time.

Quote
The astronauts realized that the problem was on the Gemini. NASA turned off the squawk box at Armstrong's home, alarming his wife[citation needed]. By now the tumble rate had reached one revolution per second, blurring the astronauts' vision and threatening loss of consciousness or vertigo. Armstrong decided to shut down the OAMS and use the Re-entry Control System (RCS) thrusters to stop the tumble. Scott later praised Armstrong's actions as their spacecraft spun: "The guy was brilliant. He knew the system so well. He found the solution, he activated the solution, under extreme circumstances ... it was my lucky day to be flying with him."[9] The spacecraft came in range of the ground communications ship Coastal Sentry Quebec. After steadying the spacecraft, the crew tested each OAMS thruster in turn and found that Number 8 had stuck on.
https://en.wikipedia.org/wiki/Gemini_8

The computer didn't know how to deal with a stuck valve and so the humans had to compensate. If they didn't know how to fly the vehicle manually and didn't train to fly the craft manually, they would be screwed as you can't program around every possible hardware malfunction interacting with the software or vice versa (at least there is no assurance that you covered them all). The article may be being slightly imprecise about the computers completely being down. For whatever reason, either hardware or software, the spacecraft wasn't performing as designed under computer control but humans could compensate in real time for whatever the control characteristics turn out to be. The simulation probably didn't include modifications of control characteristics, but this just allows them a baseline to adjust from when whatever undefined thing that could never happen actually happens. Soyuz had a similar problem with automatic docking on TMA-19M. Because the crew knew how to fly that phase manually, they were able to manually control.

Anyways, having these crews doing these simulations isn't some huge burden on a country of ~330 million.

Online Chris Bergin

FEATURE ARTICLE: ASAP reviews Boeing failure, positive SpaceX success ahead of Commercial Crew announcement -

https://www.nasaspaceflight.com/2018/07/asap-boeing-failure-positive-spacex-crew-announcement/

- By Chris Gebhardt

(Includes renders by Nathan Koga for NSF/L2)

Offline jbenton

  • Full Member
  • **
  • Posts: 218
  • Liked: 60
  • Likes Given: 214
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #395 on: 07/30/2018 07:00 pm »
United 232. Ive never known a good pilot who said they were overtrained.


Never heard of that flight before; just wiki-ed it, always nice to learn something new. Thanks

Offline jbenton

  • Full Member
  • **
  • Posts: 218
  • Liked: 60
  • Likes Given: 214
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #396 on: 07/30/2018 07:04 pm »
Virtual reality has progressed quite a bit, I can't help thinking that simulating mission failures like this will just keep getting easier and maybe even cheaper.


Also, study after study has found that the best way to improve crew moral is to give them (and especially the pilot and commander) the feeling that they are in control, no matter what.

Training them to take over when all else fails, therefore should boost confidence a great deal. Giving them that kind of training is definitely worth it then even if quadruple-redundant, rad-tolerant computers or whatever else never fail in 20 years of space ops.

Online woods170

  • IRAS fan
  • Senior Member
  • *****
  • Posts: 8843
  • IRAS fan
  • The Netherlands
  • Liked: 5903
  • Likes Given: 1994
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #397 on: 07/31/2018 10:31 am »
My current take home is the ASAP's use. Years ago they used to be a bit moany/nitpicky (Shuttle extension, early SpaceX days), but they really are showing their value over recent years.

Commercial companies (rightly to a point) do not want to anything out there unless it's fluffy PR - like the stuff they are paying Politico and PR companies to do. They hate bad news, per their image, but it doesn't matter how much some of them (Boeing Starliner) ignore media requests you always have the safety net of honest official information from the likes of the ASAP that show it will eventually get out there. Hopefully, the knowledge of that will make them realize it's in their interests to answer questions.

But I do get it. Even if a site like ours had info of an issue. We (as we do) took the correct route to ask them for clarification. We wrote a good article, a fair one, with answers.... some mass media clickbait style site would take our article, make it dramatic, and then Boeing would have wished they never picked up the initial request.

It's a minefield out there. But the ASAP meeting shows even if they don't answer, the ASAP won't be held to the same restrictions. They get answers and they put it out there in public.

With all due respect Chris but I disagree. The recent ASAP released zero new information about the nature of the Boeing hot-fire issue or the nature of the snag that's hit Merlin 1D qualification. ASAP only reported that there are problems, but not what those problems are.

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32550
  • Cape Canaveral Spaceport
  • Liked: 11343
  • Likes Given: 334
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #398 on: 07/31/2018 01:17 pm »


The computer didn't know how to deal with a stuck valve and so the humans had to compensate.

There was no computer controlling the spacecraft.   A thruster failed open and had nothing to do with the control system.   There is no difference in how the OAMS or RCS operates.  Armstrong turned off one system and turned on the other.

Like on a small fishing boat, where the outboard motor was stuck in a hard right turn, so it is turned off and the trolling motor is used.
« Last Edit: 07/31/2018 01:27 pm by Jim »

Offline clongton

  • Expert
  • Senior Member
  • *****
  • Posts: 10679
  • Connecticut
    • Direct Launcher
  • Liked: 2871
  • Likes Given: 1150
Re: Boeing's CST-100 - Master Updates and Discussion Thread 3
« Reply #399 on: 07/31/2018 02:17 pm »
With all due respect Chris but I disagree. The recent ASAP released zero new information about the nature of the Boeing hot-fire issue or the nature of the snag that's hit Merlin 1D qualification. ASAP only reported that there are problems, but not what those problems are.

The transparency Chris is alluding to is not the details of the nature of the problems but that there were, in fact, problems. Most company PR departments, left to their own devices, would hide the fact from the public that there were problems because it's not good PR. In this case the ASAP made sure those facts were made public.
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

Tags: