Not a big fan of the Virgin Orbit concept but I have to say I really respect their commitment to getting it done. The picture of the number of staff is phenomenal, there must be 300-400 people in that shot. It may be partially marketing, like all Virgin activities, but behind it is a really serious company.
Quote from: ringsider on 08/10/2017 10:00 pmNot a big fan of the Virgin Orbit concept but I have to say I really respect their commitment to getting it done. The picture of the number of staff is phenomenal, there must be 300-400 people in that shot. It may be partially marketing, like all Virgin activities, but behind it is a really serious company.Why are you not a fan of the concept?
Quote from: imprezive on 08/11/2017 05:59 pmQuote from: ringsider on 08/10/2017 10:00 pmNot a big fan of the Virgin Orbit concept but I have to say I really respect their commitment to getting it done. The picture of the number of staff is phenomenal, there must be 300-400 people in that shot. It may be partially marketing, like all Virgin activities, but behind it is a really serious company.Why are you not a fan of the concept?I think air-launch is expensive and more difficult - even though there are a few benefits, they are hard won. And the case of Virgin they use the 747 as a marketing prop from Virgin Atlantic. But as I said I actually have a lot of respect for the way they are going about it, despite my preferences. I have nothing bad to say about Virgin Orbit, they are professional and serious.
Quote from: ringsider on 08/11/2017 08:13 pmQuote from: imprezive on 08/11/2017 05:59 pmQuote from: ringsider on 08/10/2017 10:00 pmNot a big fan of the Virgin Orbit concept but I have to say I really respect their commitment to getting it done. The picture of the number of staff is phenomenal, there must be 300-400 people in that shot. It may be partially marketing, like all Virgin activities, but behind it is a really serious company.Why are you not a fan of the concept?I think air-launch is expensive and more difficult - even though there are a few benefits, they are hard won. And the case of Virgin they use the 747 as a marketing prop from Virgin Atlantic. But as I said I actually have a lot of respect for the way they are going about it, despite my preferences. I have nothing bad to say about Virgin Orbit, they are professional and serious.Air launch for a Pegasus is much cheaper and easier than using its ground equivalent Minotaur-C.
Quote from: ringsider on 08/11/2017 08:13 pmQuote from: imprezive on 08/11/2017 05:59 pmQuote from: ringsider on 08/10/2017 10:00 pmNot a big fan of the Virgin Orbit concept but I have to say I really respect their commitment to getting it done. The picture of the number of staff is phenomenal, there must be 300-400 people in that shot. It may be partially marketing, like all Virgin activities, but behind it is a really serious company.Why are you not a fan of the concept?I think air-launch is expensive and more difficult - even though there are a few benefits, they are hard won. And the case of Virgin they use the 747 as a marketing prop from Virgin Atlantic. But as I said I actually have a lot of respect for the way they are going about it, despite my preferences. I have nothing bad to say about Virgin Orbit, they are professional and serious.Peter Beck from RL has discovered the hard way that developing launch pad facilities is not any easier. Air launch has more flexibility in launch orbits and can fly round bad weather. Using common 747 is good business practice, can easily be maintained and replaced if need be. Time will tell which system is better.
Quote from: TrevorMonty on 08/12/2017 07:02 pmQuote from: ringsider on 08/11/2017 08:13 pmQuote from: imprezive on 08/11/2017 05:59 pmQuote from: ringsider on 08/10/2017 10:00 pmNot a big fan of the Virgin Orbit concept but I have to say I really respect their commitment to getting it done. The picture of the number of staff is phenomenal, there must be 300-400 people in that shot. It may be partially marketing, like all Virgin activities, but behind it is a really serious company.Why are you not a fan of the concept?I think air-launch is expensive and more difficult - even though there are a few benefits, they are hard won. And the case of Virgin they use the 747 as a marketing prop from Virgin Atlantic. But as I said I actually have a lot of respect for the way they are going about it, despite my preferences. I have nothing bad to say about Virgin Orbit, they are professional and serious.Peter Beck from RL has discovered the hard way that developing launch pad facilities is not any easier. Air launch has more flexibility in launch orbits and can fly round bad weather. Using common 747 is good business practice, can easily be maintained and replaced if need be. Time will tell which system is better.Yeah those are the supposed benefits. But the reality is the cost of airframe conversion is quite high, as is annual maintenance. I doubt that building a concrete pad and steel tower is as hard as a 747 D-check, even if Peter found it hard. It could also be he is trying to wave competitors off, you know? Make it look very hard. Then you have the added risk of humans (pilots) involved proximally to the air launch system, while it carries a liquid-fuelled rocket under-wing. That is a much bigger risk than an unmanned VL system.There is a reason so few horizontals have been built.
Cosmic Girl had a full D check before being allowed to be put to this use by the FAA, and then a conversion which probably includes some kind of fuelling / dumping system inside the plane as well as the attach / release mechanisms. None of that is trivial. So there is that cost and complexity to be considered up front.https://www.popularmechanics.com/space/rockets/amp19987/virgin-galactic-cosmic-girl-747-launch-satellites/I would be surprised if you got out of that process for less than the entire cost of a fixed pad, really surprised. That is at least 10-15m USD, plus the cost of the aircraft itself, which given the conversion is probably not on a simple lease.Everybody things horizontal is easy and cheap, but if that were true it would be much more common. There are challenges that only become obvious when you look at it really carefully. Even Virgin's L1 flight schedule acknowledges this (I posted it here a few months ago), with a ratio of aborts to successful launches. Imagine if they have to abort mid-air - what do they do with the liquid oxygen and extra RP-1 in the LV? Can't land with that for sure, so will dumping of large amounts of RP-1 into the Pacific or desert become SOP after an abort? How do you safely vent RP-1 and LOX at 500knots? What if the first LV explodes "on the pad"? I mean it's not like that is an unknown phenomenon.Again I am not knocking Virgin Orbit, I am sure they have plans, just outlining my views on the challenges of air launch.
By no means am I saying the costs are trivial but neither are the costs of building/refurbing a launch pad. According to Wikipedia SpaceX spent $20-30 million for their Vandenberg pad and $5-$10 million a year in maintenance. That's just for one pad, to hit low and high inclination orbits you'd need two.
What makes you think that you have to dump the RP1 and LOX to land?
Even Virgin's L1 flight schedule acknowledges this (I posted it here a few months ago), with a ratio of aborts to successful launches. Imagine if they have to abort mid-air - what do they do with the liquid oxygen and extra RP-1 in the LV? Can't land with that for sure, so will dumping of large amounts of RP-1 into the Pacific or desert become SOP after an abort? How do you safely vent RP-1 and LOX at 500knots?
Quote from: ringsider on 08/13/2017 07:28 amEven Virgin's L1 flight schedule acknowledges this (I posted it here a few months ago), with a ratio of aborts to successful launches. Imagine if they have to abort mid-air - what do they do with the liquid oxygen and extra RP-1 in the LV? Can't land with that for sure, so will dumping of large amounts of RP-1 into the Pacific or desert become SOP after an abort? How do you safely vent RP-1 and LOX at 500knots?Since RP-1 is just a "purer" standard for kerosene, you can pump it into the normal airplanes tanks if necessary.And dumping of kerosene is kind of standard emergency procedure for airplanes. Not nice, but most of it should evaporate before it hits the ground.Dumping LOX should be a nobrainer in my opinion.
Wow, you're right. We've never succeeded at this before. Why, remember all those X-15s that RUD'd, sending those B-52's crashing to Earth and killing the crews./sarc
.@Virgin_Orbit #LauncherOne 30 sec test of NewtonFour 5klbf LOX/RP upper stage engine (1st night test; Aug 29, 2017) instagram.com/p/BYrH9PZgu-D