[X] My Assistant

[Guest_Zvezdichko_*]

I read a very interesting article about the problems when it comes to big landers on the Red Planet ( including Mars Sample Return and manned Mars landers ).

http://www.universetoday.com/2007/07/17/th...the-red-planet/

Some quotes:

The major conclusion that came from the session was that no one has yet figured out how to safely get large masses from speeds of entry and orbit down to the surface of Mars. "We call it the Supersonic Transition Problem," said Manning. "Unique to Mars, there is a velocity-altitude gap below Mach 5. The gap is between the delivery capability of large entry systems at Mars and the capability of super-and sub-sonic decelerator technologies to get below the speed of sound."
Plainly put, with our current capabilities, a large, heavy vehicle, streaking through Mars' thin, volatile atmosphere only has about ninety seconds to slow from Mach 5 to under Mach 1, change and re-orient itself from a being a spacecraft to a lander, deploy parachutes to slow down further, then use thrusters to translate to the landing site and finally, gently touch down.

Apollo and Soyuz capsules and the proposed Crew Exploration Vehicle (CEV) will all decelerate to less than Mach 1 at about twenty kilometers above the ground just by skimming through Earth's luxuriously thick atmosphere and using a heat shield.

then:

Parachutes can only be opened at speeds less than Mach 2, and a heavy spacecraft on Mars would never go that slow by using just a heat shield. "And there are no parachutes that you could use to slow this vehicle down,��? said Manning. "That's it. You can't land a CEV on Mars unless you don't mind it being a crater on the surface."

If what's said here is true, we don't have any chance to land in a way we know - using a standart heat shield, parachute or landing thrusters.
That "Hypercone" concept is interesting and surely could be integrated for a Mars Sample Return mission, but what about a human landing mission? Wouldn't this be a challenge even to be launched with the proposed rockets like Ares 5?