fyi you got your equations wrong -- you meant mass flow rate (aka m_dot) times exhaust velocity gives you thrust.. notice that the units on this end up correct (mass*distance/time^2) whereas the mv^2 gives us Joules (in metric) aka energy - infact, you might recognize 1/2 mv^2 from highschool physics.
Also - as far as light speed goes - yes, I guess your particle mass would approach infinity, but then so would your power requiremnent (its not just a voltage difference), wouldn't it? And even a nuclear reactor can't provide inifite power.
Also, generally ion engines have charged plates to accelerate the ionized fuel, these would wear out pretty quickly if you were bombarding them with infinitly massize particles moving at light speed.. even if they were made out of "unobtanium."
Finally, practically speaking ion engines CANNOT function in atmospheres - the ambient pressure of an atmosphere will "out push" the pressure produced at the mouth of the thruster by the thruster. With a nuclear reactor - I don't know - I do agree that it'd be nice if someone would cough up the cash for that...
What do you mean by an "error prone automatic flight control system"? The only errors with regards to entry FCS I can think of recently have been with a Soyuz CAPSULE this past Feb..
And as far as capsules go - for returning a few people they're ok - but your talking a pretty big capsule if you want to drop a crew of seven, their living quarters (for few a weeks) a sizable lab, and some payload back into the atmosphere. That's pretty much what the shuttle mission entails, and before you go extolling the virtues of capsules and lambasting NASA (not that they don't deserve it for other reasons) think a little bit about some of the problems of giant re-entry capsules: their shape (a cone? no the diameters too big, a sphere, a cylinder? don't think that's too stable), parachute scaling problems, payload bay locations, structural problems upon landing (shuttle landings are gentle, but I'd guess they are when compared to capsule landings), issues with science packages at impact, etc..
Granted, for the OSP mission, a capsule might be ok, but what if NASA wants to build on the OSP project, then they've taken a big expensive step in the wrong direction. Short Answer - Capsules are a dead end (and, hence boring).
Maybe a Delta Clipper type design (but multi-stage) deserves a closer look? But personally I think wings are fine, and, in the long run, precisely what one wants in an atmosphere.
Getting specific - I think the boat house money came from donations, specifically to build a boat house. Effect on tuition = 0. What's more, typically crew people tend to make lots of money after graduation (crew folk tend to be big, outgoing and aggressive people and can, hence, can generally do quite well in the rat race) - happy crew people mean more donations, and a bigger endowment. As far as I can tell, this is pretty consistent with Princeton's investment policy: construction of buildings, sponsoring events (aka reunions) etc that one might consider useless can be considered well spent money within the bounds of this discussion (ie pertaining to decreasing the burden of tuition on the middle class) given a slightly different perspective.
As far as your friends in Seattle who lost out due to frugal parents - that is indeed too bad, but this is no longer such an issue given that (1) equity is not heavily valued in the financial aid process (I think humblecoder mentioned this briefly) and (2) financial aid officers do indeed look at incoming students on a case by case basis - and can differentiate between a poor family and a family that just started payments on a 2 million dollar home and has maxed out credit cards.
Finally: I notice you're opposed to high tuition AND grants (as opposed to loans). The latter translates to low tuition for less well off people. In effect you opposed to high tuition AND low tuition - you're a tough one to please.
fyi - I'm a black guy from a middle class family (from rural Michigan) and I went to Princeton. Most of my friends from college are from middle class families (granted, primarily in the US and Canada). I did not feel uncomfortable or out of place at Princeton - although given what you've written, I guess I should have?
And I didn't row (meaning I wasn't on the crew team).
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fyi you got your equations wrong -- you meant mass flow rate (aka m_dot) times exhaust velocity gives you thrust .. notice that the units on this end up correct (mass*distance/time^2) whereas the mv^2 gives us Joules (in metric) aka energy - infact, you might recognize 1/2 mv^2 from highschool physics.
.. even if they were made out of "unobtanium."
Also - as far as light speed goes - yes, I guess your particle mass would approach infinity, but then so would your power requiremnent (its not just a voltage difference), wouldn't it? And even a nuclear reactor can't provide inifite power.
Also, generally ion engines have charged plates to accelerate the ionized fuel, these would wear out pretty quickly if you were bombarding them with infinitly massize particles moving at light speed
Finally, practically speaking ion engines CANNOT function in atmospheres - the ambient pressure of an atmosphere will "out push" the pressure produced at the mouth of the thruster by the thruster. With a nuclear reactor - I don't know - I do agree that it'd be nice if someone would cough up the cash for that...
What do you mean by an "error prone automatic flight control system"? The only errors with regards to entry FCS I can think of recently have been with a Soyuz CAPSULE this past Feb ..
..
And as far as capsules go - for returning a few people they're ok - but your talking a pretty big capsule if you want to drop a crew of seven, their living quarters (for few a weeks) a sizable lab, and some payload back into the atmosphere. That's pretty much what the shuttle mission entails, and before you go extolling the virtues of capsules and lambasting NASA (not that they don't deserve it for other reasons) think a little bit about some of the problems of giant re-entry capsules: their shape (a cone? no the diameters too big, a sphere, a cylinder? don't think that's too stable), parachute scaling problems, payload bay locations, structural problems upon landing (shuttle landings are gentle, but I'd guess they are when compared to capsule landings), issues with science packages at impact, etc
Granted, for the OSP mission, a capsule might be ok, but what if NASA wants to build on the OSP project, then they've taken a big expensive step in the wrong direction. Short Answer - Capsules are a dead end (and, hence boring).
Maybe a Delta Clipper type design (but multi-stage) deserves a closer look? But personally I think wings are fine, and, in the long run, precisely what one wants in an atmosphere.
It sounds like you're talking about the solar orbit transfer vehicle (currently on $$ hold, I think):
http://www.boeing.com/ids/flash.html (products a to z)
I know X-15 back in the late 60s used some sort of spray on ablative heat sheild (http://www.dfrc.nasa.gov/gallery/photo/X-15/Small /ECN-1736.jpg).
What happened to this approach - was it insufficient for re-entry velocities?
Getting specific - I think the boat house money came from donations, specifically to build a boat house. Effect on tuition = 0. What's more, typically crew people tend to make lots of money after graduation (crew folk tend to be big, outgoing and aggressive people and can, hence, can generally do quite well in the rat race) - happy crew people mean more donations, and a bigger endowment. As far as I can tell, this is pretty consistent with Princeton's investment policy: construction of buildings, sponsoring events (aka reunions) etc that one might consider useless can be considered well spent money within the bounds of this discussion (ie pertaining to decreasing the burden of tuition on the middle class) given a slightly different perspective. As far as your friends in Seattle who lost out due to frugal parents - that is indeed too bad, but this is no longer such an issue given that (1) equity is not heavily valued in the financial aid process (I think humblecoder mentioned this briefly) and (2) financial aid officers do indeed look at incoming students on a case by case basis - and can differentiate between a poor family and a family that just started payments on a 2 million dollar home and has maxed out credit cards. Finally: I notice you're opposed to high tuition AND grants (as opposed to loans). The latter translates to low tuition for less well off people. In effect you opposed to high tuition AND low tuition - you're a tough one to please. fyi - I'm a black guy from a middle class family (from rural Michigan) and I went to Princeton. Most of my friends from college are from middle class families (granted, primarily in the US and Canada). I did not feel uncomfortable or out of place at Princeton - although given what you've written, I guess I should have? And I didn't row (meaning I wasn't on the crew team).