Lunar Lander in a 5.2m faring?

In article .com,
Alex Terrell wrote:
T-Space proposal to NASA was for a tall (16.45m) thin (6.7m) lander
with two small floors for habitation, and LH2 and LOX tanks above...
Are there control problems in landing such a tall craft?

Nothing fundamental. The big problem with such a vehicle comes if you put
the crew on *top*, which means they are far away from the surface and do
not have a particularly good view of what's happening during landing.
Putting the tanks on top, instead of on the bottom, avoids that.

I also raised the dual engine concpet, with the payload in the middle.
However, both engines must work. Can the concept work?

Not ridiculous. There have been such proposals.

I've seen very little disucssion about "man-rating" lunar landers.

Since "man-rating" nowadays is basically an excuse used to justify NASA's
preconceptions about how the program should be run, it naturally isn't a
significant issue for a NASA-designed spacecraft.

...probably the riskiest part of the mission, since no escape system
can save the crew from an engine failure after launch or just before
landing...

Fortunately, sudden bolt-out-of-the-blue failures in liquid rocket engines
are actually fairly uncommon. More usually, if the thing starts at all,
it keeps running thereafter.

Should NASA use a Spacex "engine-out" capable design, with
five or more engines?

It would have its points. The questions are, to what extent does the
greater complexity make other kinds of failures more likely, and is the
extra trouble worth it? Many smaller aircraft, especially helicopters,
have "black zones", just before landing and just after takeoff, in which
an engine failure is likely to prove fatal; this is simply accepted.
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