Virgin Galactic
Discussion
Eric Mc said:
All aircraft have to be tested by test pilots before passengers can be carried. There are lots of examples of early versions of airliners or civil aircraft having problems that were sorted out in test before entering airline service.
Are you saying because there has been a problem they should give up?
Nah, that would be virgin on the ridiculous...Are you saying because there has been a problem they should give up?
Eric Mc said:
All aircraft have to be tested by test pilots before passengers can be carried. There are lots of examples of early versions of airliners or civil aircraft having problems that were sorted out in test before entering airline service.
Are you saying because there has been a problem they should give up?
I think we have gone beyond wood, string and canvas!! and some semblance of both scientific and engineering rigour is applied to any form of transportation these daysAre you saying because there has been a problem they should give up?
Given the amount of modelling that can be done (and I should suspect a fair amount has been applied to this project) I think it would be considered reasonable that you don't have passengers killed for every x number of launches. X,xxx,xxx maybe but not X or even xxx. so safety would be at the No1 spot for all of these new rocket companies and I would think that would play a part in getting a licence to launch these rockets.
Looking at Aviation statistics it is a reasonable risk to catch a flight, however depending which type of design or carrier statistically increases or decreases the probability of mortality.
So using this link http://www.airsafe.com/events/models/rate_mod.htm will highlight this
Engine manufactures have pretty much sorted their reliability for example Rolls Royce "In that time, our Trent 900s have accumulated over 600,000 engine flying hours and recorded zero basic engine delays and zero engine-related diversions, turnbacks or aborted takeoffs." http://www.rolls-royce.com/news/press_releases/201...
Quoting the wall street Journal: http://www.wsj.com/articles/problems-plagued-virgi...
"In 2012 and 2013, despite continuing performance problems with the engine, which burned a rubber compound combined with an oxidizer, the engineer recalled, Virgin Galactic kept saying Mr. Branson’s flight was less than a year away"...
"Also, the motor didn’t have enough power to blast the proposed 60-foot spaceship, six passengers and a crew of two to the required altitude. Sierra blamed Virgin Galactic for making SpaceShipTwo overweight and urged a temporary compromise to take up fewer passengers, according to the engineer familiar with the project.
Virgin Galactic responded it couldn’t make money under such circumstances, the person said. The partners responded by parting ways on engine development, and Virgin Galactic engineers switched to a new plastic-based fuel intended to boost the rocket’s power.."
When considering the time Rolls Royce have taken developing their engine for public transportation, our rocket ship dreams may have a long way to go before being acceptably safe. On one level it has been argued that "with current rocket technology its an acceptable risk" Just tell that to the devastation left behind to those families that have to deal with the death of a lost one. (particularly if they are just a passenger)
On that last part about parting ways on the engine development is this what is now happening with the pilots?
It will certainly be interesting to watch how this all plays out, but I would argue you cannot align this with the early days of the airline industry we are much more aware of the risks and dangers associated with it.
Edited by Toaster on Sunday 18th January 17:56
Toaster said:
Looking at Aviation statistics it is a reasonable risk to catch a flight, however depending which type of design or carrier statistically increases or decreases the probability of mortality.
I think it's worth remembering that the reason commercial air transport is now so safe, is that it wasn't very safe to begin with! What i mean is that we have "learnt" how to fly safely, from how we deign the planes, to how we license, operate and maintain them. All that crucial information that builds into a full "safety case" simply isn't available for space flight yet. Even programs like the Shuttle, with hundreds of flights, are not "statistically confident" in terms of the methodology and probability for all the possible failure cases.Max_Torque said:
I think it's worth remembering that the reason commercial air transport is now so safe, is that it wasn't very safe to begin with! What i mean is that we have "learnt" how to fly safely, from how we deign the planes, to how we license, operate and maintain them. All that crucial information that builds into a full "safety case" simply isn't available for space flight yet. Even programs like the Shuttle, with hundreds of flights, are not "statistically confident" in terms of the methodology and probability for all the possible failure cases.
Interesting, but most of the time the suborbital flight such as Virgin Galactic is mainly as an aircraft so you would think that at least x percent of the flight would be as safe as a conventional aircraft, consider this which was written in 2003 :"If commercial aviation had the same accident rate as the shuttle “thousands of people would be killed each day—which the citizens of this nation simply would not stand,” said Rep. Barton." http://www.thespacereview.com/article/36/1
So just quoting "early days of air transport" IMHO doesn't holds much water because we do have higher safety expectations even if it is (near) space flight
Here is an interesting article General Public Space Travel and Tourism - Volume 1 Executive Summary http://www.spacefuture.com/archive/general_public_...
Your point about statistical robustness due to lack of flight statistics is a good point you make and not one that is lost on the insurance industry
http://www.nerdwallet.com/blog/investing/2013/spac...
http://www.sciencedirect.com/science/article/pii/S...
Out of interest Lloyd's of London and Nasa struck a deal years ago to rescue two satellites http://www.apnewsarchive.com/1985/Lloyd-s-Thanks-S...
Edited by Toaster on Monday 19th January 06:58
You can quote all you like. Spaceflight is still in its early stages as far as launching people on the end of rockets is concerned. After 50 plus years of manned launches, we've still done it less than a thousand times - and the launch phase of each mission barely lasts ten minutes - so the total number of HOURS of manned launch experience is still tiny.
Even if you add in the various rocket plane programmes - such as the X-15 (which is the only really comparable programme to Virgin Galactic) - you are still only adding a further couple of hundred hours - which is not much in aviation terms.
Compare this to the MILLIONS of flight hours that were accumulated over the first 50 years of heavier than air flight.
Although it shares a common heritage, space flight is different in many ways to air travel - and we are still learning.
Even if you add in the various rocket plane programmes - such as the X-15 (which is the only really comparable programme to Virgin Galactic) - you are still only adding a further couple of hundred hours - which is not much in aviation terms.
Compare this to the MILLIONS of flight hours that were accumulated over the first 50 years of heavier than air flight.
Although it shares a common heritage, space flight is different in many ways to air travel - and we are still learning.
Eric Mc said:
You can quote all you like. Spaceflight is still in its early stages as far as launching people on the end of rockets is concerned. After 50 plus years of manned launches, we've still done it less than a thousand times - and the launch phase of each mission barely lasts ten minutes - so the total number of HOURS of manned launch experience is still tiny.
Even if you add in the various rocket plane programmes - such as the X-15 (which is the only really comparable programme to Virgin Galactic) - you are still only adding a further couple of hundred hours - which is not much in aviation terms.
Compare this to the MILLIONS of flight hours that were accumulated over the first 50 years of heavier than air flight.
Although it shares a common heritage, space flight is different in many ways to air travel - and we are still learning.
Quoting, referencing and critically reviewing articles and having these peered reviewed is the foundation of Science, this is a Science thread not a "lets spout opinon thread" without referencing articles that come from the industry how on earth can this thread have any debate?Even if you add in the various rocket plane programmes - such as the X-15 (which is the only really comparable programme to Virgin Galactic) - you are still only adding a further couple of hundred hours - which is not much in aviation terms.
Compare this to the MILLIONS of flight hours that were accumulated over the first 50 years of heavier than air flight.
Although it shares a common heritage, space flight is different in many ways to air travel - and we are still learning.
Virgin Galactic's current craft is more aircraft than space craft given its short time in space and no orbit capability at this time. Now that is not saying it is not flying at a high altitude and has challenges to go with it, it is a hybrid vehicle.
I do not pretend to have answers to the questions involved however reviewing articles both + and - does give a more balanced view, clearly getting in to space requires huge amounts of energy is currently risky.
Those Millions of hours you quote all contribute to getting Virgin to where they are by using the various engineering companies Virgin have, this means they are tapping in to that knowledge both aviation and space.
So tell me Mr Eric at least two instances of changing suppliers have been quoted in the press 1) engine supplier 2) pilots in the context of the article why do you think this is?
You've obviously got a very negative opinion of the project so no matter what I put to you, you will counter with a string of negatives. So, what is the point of further discussion?
If the guy wants to have a go doing this, let him do it.
If people want to have a go on his craft - let them.
If you don't like what he's doing and think it's risky - don't buy a ticket.
Rather than continually trawl up reasons (real or concocted) as to why he shouldn't be carrying out this project, can't we chat about the technical aspects in a more sensible, neutral way?
If the guy wants to have a go doing this, let him do it.
If people want to have a go on his craft - let them.
If you don't like what he's doing and think it's risky - don't buy a ticket.
Rather than continually trawl up reasons (real or concocted) as to why he shouldn't be carrying out this project, can't we chat about the technical aspects in a more sensible, neutral way?
Eric Mc said:
You've obviously got a very negative opinion of the project so no matter what I put to you, you will counter with a string of negatives. So, what is the point of further discussion?
If the guy wants to have a go doing this, let him do it.
If people want to have a go on his craft - let them.
If you don't like what he's doing and think it's risky - don't buy a ticket.
Rather than continually trawl up reasons (real or concocted) as to why he shouldn't be carrying out this project, can't we chat about the technical aspects in a more sensible, neutral way?
I think the previous post I did had +'s and -'s so its OK for you to be selective and tell people about books you have read but not OK for me to post links and comment with counter views.......what a boring world it would be if we all agreedIf the guy wants to have a go doing this, let him do it.
If people want to have a go on his craft - let them.
If you don't like what he's doing and think it's risky - don't buy a ticket.
Rather than continually trawl up reasons (real or concocted) as to why he shouldn't be carrying out this project, can't we chat about the technical aspects in a more sensible, neutral way?
There is more than one truth not all sits well or is comfortable but that makes life more exciting and interesting plus we all learn more
I'm all for interesting and exciting.
And this project is interesting and exciting - if a bit dodgy.
I'm all for dodgy too - although I may not be a volunteer
Let's just see if it pans out. It may turn out to be a bit of a dud. Or it could be the first chapter in a new form of travel. Who knows.
I'm prepared to give it a chance.
And this project is interesting and exciting - if a bit dodgy.
I'm all for dodgy too - although I may not be a volunteer
Let's just see if it pans out. It may turn out to be a bit of a dud. Or it could be the first chapter in a new form of travel. Who knows.
I'm prepared to give it a chance.
I see Virgin Galactic are now going it alone, ending ties with Scaled Composites.
http://www.dailymail.co.uk/sciencetech/article-292...
Sounds like they are throwing the baby, bathwater and all the toys out. That's a whole lot of expertise they are casting aside simply to (one assumes) distance themselves from the accident.
http://www.dailymail.co.uk/sciencetech/article-292...
Sounds like they are throwing the baby, bathwater and all the toys out. That's a whole lot of expertise they are casting aside simply to (one assumes) distance themselves from the accident.
Interesting article http://www.flightglobal.com/news/articles/analysis...
This statement does seem to highlight more testing and development is required.
"Alarmingly for a craft that had achieved altitudes of about 70,000ft during its three successful powered test flights – but needs to touch 330,000ft to reach the edge of space – fuel for SS2’s liquid-solid hybrid rocket motor has been an issue throughout."
"At this point, discussion of Virgin Galactic’s next move must be speculation. But some observers, noting that the number of deaths in spaceflight and training accidents totals about 5% of the complement to date of space travellers, reckon that commercial risk considerations will force Branson to find a face-saving way to bring the programme to a close".
It will be interesting to see the NTSB's involvement /statement/recommendations when they have finished their enquiry
Toaster said:
"At this point, discussion of Virgin Galactic’s next move must be speculation. But some observers, noting that the number of deaths in spaceflight and training accidents totals about 5% of the complement to date of space travellers, reckon that commercial risk considerations will force Branson to find a face-saving way to bring the programme to a close".
I don't really understand what ^^^^that means? I mean, last week, something like 200 people died in commercial aviation accidents. The "average" death rate is only very low because during that week, 10Million or so people flew. So, by that measure, how can space flight ever be "safe" until enough people fly to make it safe. I mean, the space shuttle, the riskiest space craft ever, killed only 14 people. More people probably die every year in planes choking on the free peanuts!Max_Torque said:
I don't really understand what ^^^^that means? I mean, last week, something like 200 people died in commercial aviation accidents. The "average" death rate is only very low because during that week, 10Million or so people flew. So, by that measure, how can space flight ever be "safe" until enough people fly to make it safe. I mean, the space shuttle, the riskiest space craft ever, killed only 14 people. More people probably die every year in planes choking on the free peanuts!
"If commercial aviation had the same accident rate as the shuttle “thousands of people would be killed each day—which the citizens of this nation simply would not stand,” said Rep. Barton." http://www.thespacereview.com/article/36/1Oh and its probably best not to eat peanuts when weightless;)
Toaster said:
Max_Torque said:
I don't really understand what ^^^^that means? I mean, last week, something like 200 people died in commercial aviation accidents. The "average" death rate is only very low because during that week, 10Million or so people flew. So, by that measure, how can space flight ever be "safe" until enough people fly to make it safe. I mean, the space shuttle, the riskiest space craft ever, killed only 14 people. More people probably die every year in planes choking on the free peanuts!
"If commercial aviation had the same accident rate as the shuttle “thousands of people would be killed each day—which the citizens of this nation simply would not stand,” said Rep. Barton." http://www.thespacereview.com/article/36/1Oh and its probably best not to eat peanuts when weightless;)
Max_Torque said:
Indeed, but you still can't base commercial space flight risk probability on the space launches to date! I mean, even if not a single person more was killed or injured in ANY future space system, we'd still have to launch several hundred thousand, and possible million space missions to bring the odds down to those currently experienced by commercial air transport!
Yes you can and the failure rate is currently significant. Are you saying that the current statistics should be ignored for commercial gain? and is it OK when you see this sort of statement?"Alarmingly for a craft that had achieved altitudes of about 70,000ft during its three successful powered test flights – but needs to touch 330,000ft to reach the edge of space – fuel for SS2’s liquid-solid hybrid rocket motor has been an issue throughout."
Now this is more like it.........and its british
Developed by Reaction Engines over the last 20 years, SABRE (Synergetic Air-Breathing Rocket Engine) is a new engine class that can operate in both air-breathing and rocket modes.
http://www.reactionengines.co.uk/press_release.htm...
Virgin Galactic Takes a Cautious Path to Spaceflight:
I wonder why couldn't be because now there has been deaths they can't afford a second catastrophe?
Quote taken from here http://www.nbcnews.com/storyline/virgin-voyage/vir...
Before the accident, company founder Richard Branson issued statements saying SpaceShipTwo would fly paying passengers to the edge of space within one to three years — whether that translated into 2007, or 2008, 2012, 2013, 2014 or 2015.
"Sometimes people misinterpreted those as firm dates or promises," said Will Pomerantz, Virgin Galactic's vice president for projects, "so we don't want to repeat that mistake."
ROFL
so What Sir Richard said was taken out of context? oh OK looks like the Marketing department just had its wings clipped.
Whilst I am not in favour of this joyride (waste of resources etc and pointless slingshot up and down) If and when launches happen I wish all a very safe journey
I wonder why couldn't be because now there has been deaths they can't afford a second catastrophe?
Quote taken from here http://www.nbcnews.com/storyline/virgin-voyage/vir...
Before the accident, company founder Richard Branson issued statements saying SpaceShipTwo would fly paying passengers to the edge of space within one to three years — whether that translated into 2007, or 2008, 2012, 2013, 2014 or 2015.
"Sometimes people misinterpreted those as firm dates or promises," said Will Pomerantz, Virgin Galactic's vice president for projects, "so we don't want to repeat that mistake."
ROFL
so What Sir Richard said was taken out of context? oh OK looks like the Marketing department just had its wings clipped.Whilst I am not in favour of this joyride (waste of resources etc and pointless slingshot up and down) If and when launches happen I wish all a very safe journey
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