SpaceX's Demo-1 green lit for launch as Virgin enjoys a brief ménage à trois aboard VSS Unity Scientists sharpened their view of Ultima Thule last week, while three more space Virgins popped their commercial astro cherries aboard SpaceShipTwo and Elon Musk revealed the fate he has in store for last week's Falcon 9. I'm ready for my close-up, Dr Stern The New Horizons team celebrated the latest dribble of data from the …
"Get yer arses over the Karman Line or you ain't in space."
They got to 89.9181 km - not far short of that 100 km "border". I expect they'll continue to expand the flight envelope by cautious increments and will get over the Karman line in the next few flights.
I've read of the X-15 flights that "Over thirteen flights, eight pilots flew above 264,000 feet or 50 miles (~80.47km), thereby qualifying as astronauts according to the United States definition of the space border." - so by that definition, VSS Unity has already made it. Okay, VSS Unity can't go as fast as an X-15, but I suspect it's a good deal more comfortable to ride in and cheaper to run.
> I expect they'll continue to expand the flight envelope
No, because this was a full thrust flight, with the rocket "givin' it all she can, cap'n!" so there isn't anything to expand. Unless they fit a bigger rocket, this is as high as it goes.
Edit: if you look at pictures, you can see the rocket nozzle almost completely ablated (eroded away)
"No, because this was a full thrust flight, with the rocket "givin' it all she can, cap'n!" so there isn't anything to expand. Unless they fit a bigger rocket, this is as high as it goes.
Edit: if you look at pictures, you can see the rocket nozzle almost completely ablated (eroded away)"
I assume what you say is true - although I've not been able to find anything on-line which states so. I've not managed to find a picture showing the engine nozzle in detail after the flight, either.
(could anyone provide pointers?)
But: the trajectory used might not have been the optimum one for maximum altitude - they were only about 10% short of real space altitude, so perhaps a better optimized trajectory is all that's needed.
And there's always the possibility that the engine wasn't run until the solid fuel was fully exhausted - just to play it slightly cautiously in this case. So perhaps there's the possibility of getting a wee bit more total impulse out of the current engine without any changes to the construction.
I can't help feeling that Virgin Galactic is going to want to get past the Karman line with this craft. It might not take a new rocket engine design if more total impulse is needed rather than just trajectory optimization. One could perhaps improve efficiency by using a higher oxidiser input pressure, which wouldn't necessarily need big changes to anything. It might be that there are gains to be had with a different nozzle design - any rocket nozzle is some sort of compromise.
And I can't help wondering if it'd be possible just to make the engine's solid fuel cylinder a wee bit longer without upsetting anything seriously, to provide a bit more total impulse.
You could perhaps get a couple of percent extra from each of several optimizations and improvements which would most likely do the trick in the end, I reckon. Pure speculation on my part, of course. We'll see what the future holds when it comes along.
Gwynne Shotwell did an interview recently and for those that actively follow Spacex, there was a camera shot that hasn't to my knowledge being previously released, the view from the fairing as it is released from the payload/second stage.
https://www.youtube.com/watch?v=X1mp1j0ef8c
(It took a while to sink it what the view was).
At time 4.48. Worth a watch.
If anyone from SpaceX is reading (hopefully Gwynne Shotwell), can we have the full landing video from the Nusantara Satu Mission, it was cut-off during the decent when unusual sparks started for eminate from the base, hopefully the footage is now available after a successful recovery.
> can we have the full landing video
That is probably all they have. Re-entry causes ionization of the atmosphere, which blocks radio transmissions. There are dodges such as trying to transmit to satellites through holes in the top of the ionization sheath, but I don't think SpaceX does that.
We know from previous landings that it's recorded locally as well, or we wouldn't have https://www.youtube.com/watch?v=bvim4rsNHkQ (How not to land an orbital booster).
Sure, they lose the live telemetry, but unless the camera/storage is destroyed, they should have the local footage.
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