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Another reason for not using parachutes or things like the deployable aeroshell is that they are not reusable, or not quickly reusable.

I wonder how many of the proposals/suggestions made in these threads were considered by SpX engineers. I would bet they've considered a wide range of technologies and techniques.

(that's not to say I don't enjoy this sort of monday morning quaterbacking - it gets the brain juices flowing)
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Scientists receive $1.3 million to study new propulsion idea for spacecraft:
https://www.plymouth.ac.uk/news/scientists-receive-13-million-to-study-new-propulsion-idea-for-spacecraft
We should all congratulate Mike McCulloch, this is a monumental achievement and a big step for the emdrive generally. There are several contributors to this forum who deserve to be funded, lets hope that Mike is in the first few of many.
       Good on you Mike, keep up the good work trying to make sense of this.

Ehhumm...  :o It looks now that the EmDrive doesn't work. So that would mean McCulloch's theory predicts an effect which doesn't exist.
His model gives a formula which reasonably predicts the rotational velocities of galaxies. I think that's all of his success up to now. And there are a dozen or so other theories which also reasonably predict these curves. So that doesn't prove a lot.
What McCulloch does very well, is yelling that his theory is superior to General Relativity and there are quite some laymen who tend to believe him.
He has some basic ideas which are interesting, and probably worth further investigating. But until some basic features are (theoretically) explored, like solar system dynamics (perihelium shift of Mercury and so on), it is grotesque to claim that his theory is superior.

At least a year ago I told him I didn't trust his model because it predicts ALL anomalous effects. Pioneer Anomaly, EmDrive, Woodward thruster, Flyby Anomaly, etc. And I was sure that at least some of them would turn out not to exist at all. 
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SpaceX BFR - Earth to Deep Space / Re: BFR GTO capability
« Last post by Semmel on Today at 11:06 AM »
At least for this question, it's easy to answer - if you believe the presentation.(*)
That states it can do  3300m/s with a VIP of say 5% of the stage dry mass with 250m/s of landing fuel.

I must have missed it, was that number in the presentation?
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Another reason for not using parachutes or things like the deployable aeroshell is that they are not reusable, or not quickly reusable.
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You don't want to do that.
Doing the deceleration significantly faster than it is currently being done (3G or so peak) means you can't have paying passengers onboard.
You also need to be able to carefully manage the lift, not just the drag, to achieve reasonable reentries from supra-orbital trajectories.

Ah, so  currently passengers would experience up to 3 G's even during re-entry? That's when returning from the Moon specifically?

In which direction would they feel these 3 G's? Which way would they have to be seated to endure them?
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Not necessarily, find the mass and surface area for both concepts. Divide the mass by the surface area, that should give you your answer.
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Well, my point was just about achieving more braking than you'd get from brakeron-fins, and not about achieving the same level of deceleration required for a full-on parachute landing.
You don't want to do that.
Doing the deceleration significantly faster than it is currently being done (3G or so peak) means you can't have paying passengers onboard.
You also need to be able to carefully manage the lift, not just the drag, to achieve reasonable reentries from supra-orbital trajectories.
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Edit: oddly, no analysis of active pixel offsets; nor any difference imaging.

--- Tony

Something interesting in their observations that they want to check and re-check before talking about?
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I will definitely watch it! .. unless reviews and trailer really suck.

It is true that it would be very nice to have more (or any) hard SF movies that
(a) do not use the aliens trope.
(b) do not just use space as some sort of metaphor for isolation.

.. but I would be a hermit living in a cave if I waited for the movie I really want.

wait a minute.. I AM a hermit living in a cave!!! What HAPPENED!
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It goes from vertical to horizontal (ish) about three minutes before landing, at a velocity of around mach 2, 25km up, and a few km downrange.

So just for clarity, it's still traveling belly-first throughout that transition you've described from vertical to horizontal-ish?
Yes.
Unless you are entering from >> LEO, you do not at any time have the windows pointed at earth.
It varies from windows looking mostly back, to mostly up, with the belly forward, to down.
There are some 's-turns' to manage energy, and trim entry (again making a case for s-foils) but the maximum roll is not approaching 90 degrees.

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