New LLTV Needed?

I was wondering what the groups thinks of the need to build an
"LLTV 2.0" to train future Moon bound astronauts, or has simulation
advanced to a state where such an effort is superfluous and needlessly
risky?
Thanks

wrote:

I was wondering what the groups thinks of the need to build an
"LLTV 2.0" to train future Moon bound astronauts, or has simulation
advanced to a state where such an effort is superfluous and needlessly
risky?



Given the abilities of today's flight simulators, it's probably not
necessary to rebuild one; especially considering what happened to the
one Armstrong was flying. :-)
To give you some idea of how well the modern simulators work, all the
original batch of F-117 stealth fighter pilots made their first flights
in the aircraft solo and at night- and that was around twenty years ago.

Pat

Pat Flannery wrote:
wrote:

I was wondering what the groups thinks of the need to build an
"LLTV 2.0" to train future Moon bound astronauts, or has simulation
advanced to a state where such an effort is superfluous and needlessly
risky?



Given the abilities of today's flight simulators, it's probably not
necessary to rebuild one; especially considering what happened to the
one Armstrong was flying. :-)
To give you some idea of how well the modern simulators work, all the
original batch of F-117 stealth fighter pilots made their first flights
in the aircraft solo and at night- and that was around twenty years ago.

Pat

I worder if a Harrier could be used as a Lunar Landing Training
Vehicle?

Rusty

I'm an airline pilot and am well aware of the advances in this
technology. Although we train on them and can be released to do our
first trips on a fer real airplane with fare paying passengers, this is
done under supervision of training captains and until such time as the
pilot is deemed to have shown appropriate competence to be released to
regular line flying. Knowing that flying an aluminum cloud is not
really the same as touching down on another planet, I still wonder if
the potential confidence building experience acquired in a non virtual
training device would be considered valuable enough to go ahead with
such a vehicle--as is still done today with the Shuttle Training
Aircraft. Certainly, Shuttle approaches are probably very well mimicked
in a simulator and yet NASA continues to operate these aircraft at what
must be considerable cost.
I hadn't thought of a modified Harrier for such work,
Rusty--interesting notion.

In article . com,
wrote:
I was wondering what the groups thinks of the need to build an
"LLTV 2.0" to train future Moon bound astronauts, or has simulation
advanced to a state where such an effort is superfluous and needlessly
risky?

You forgot "excessively costly". :-)

I predict that "superfluous" will be the official story.

Whether that's the truth is a more complicated question. Simulation
technology has gotten *much* better since Apollo, for sure. Another
factor that shouldn't be overlooked is that not only were the Apollo
simulators pretty crude by modern standards, but at the time when the
early landing crews were using the LLTVs, the simulators weren't yet
working very well. The simulators themselves took a lot of debugging, and
their early reliability was so poor that simulator downtime threatened to
hamper training enough to delay flights. So there were reasons why the
LLTVs looked more important then than they would today.

That said, my feeling is that the dominant issue is that today's NASA
would need more time and a lot more money to produce an LLTV equivalent,
so the reduced need for it will be used as an excuse to bypass it
altogether.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

"Rusty" wrote in message
oups.com...

Pat Flannery wrote:
wrote:

I was wondering what the groups thinks of the need to build an
"LLTV 2.0" to train future Moon bound astronauts, or has simulation
advanced to a state where such an effort is superfluous and needlessly
risky?



Given the abilities of today's flight simulators, it's probably not
necessary to rebuild one; especially considering what happened to the
one Armstrong was flying. :-)
To give you some idea of how well the modern simulators work, all the
original batch of F-117 stealth fighter pilots made their first flights
in the aircraft solo and at night- and that was around twenty years ago.

Pat

I worder if a Harrier could be used as a Lunar Landing Training
Vehicle?

Rusty

You're better off with a helicopter. The LLTV design was needed because
they couldn't fly a computer with emulation software. That's not a problem
today. The LLTV cockpit simulator could be located aft of the real cockpit,
allowing you to have normal controls and a normal pilot to take over in case
things got hinky.

My guess here is that NASA won't spend the money. They'll rely entirely on
simulators.

Rusty wrote:

I worder if a Harrier could be used as a Lunar Landing Training
Vehicle?



I don't think they'd fly the same- the closest thing might be a
helicopter. The Soviet's used a helicopter as their LK simulator- They
had Alexi Leonov doing autorotating landings with it over and over
again, until he became convinced that they were going to kill him long
before he got anywhere near the Moon.
There's really no need to go to all the trouble of making a flying
simulator, they can program a computer simulator to operate exactly the
way the real one will. In fact, it will be easier than doing one for a
aircraft because there is no atmosphere to deal with, so air drag and
wind don't need to be figured in.

Pat

wrote:

I still wonder if
the potential confidence building experience acquired in a non virtual
training device would be considered valuable enough to go ahead with
such a vehicle--as is still done today with the Shuttle Training
Aircraft.


But as I said in the earlier reply, the Shuttle has the atmosphere to
deal with- crosswinds, gusts, and turbulence that may arise unexpectedly
as it comes in to land. The Moon doesn't suffer from those problems, so
the landing is a fairly straightforward application of Newtonian physics.

Certainly, Shuttle approaches are probably very well mimicked
in a simulator and yet NASA continues to operate these aircraft at what
must be considerable cost.
I hadn't thought of a modified Harrier for such work,
Rusty--interesting notion.



The Harrier isn't the safest aircraft in the world to land by a long shot.
Any psychological advantage gained by using it must be weighed against
the possibility that you kill astronauts during training- a helicopter
would make a far safer alternative, and probably fly far more like the
actual lander than the Harrier would.
One thing both a Harrier and a helicopter would encounter is ground
effect caused by their downwash being reflected off the ground back up
at them as they made their final approach. I don't think this will
happen to any great extent on the Moon due to the low thrust needed to
land, and the fact that one is landing in a vacuum.
If you want them to get a feel for how the lander handles, the place to
do it is probably in Earth orbit.

Pat

In article ,
Pat Flannery wrote:
deal with- crosswinds, gusts, and turbulence that may arise unexpectedly
as it comes in to land. The Moon doesn't suffer from those problems, so
the landing is a fairly straightforward application of Newtonian physics.

The details matter, unfortunately.

For example, the Apollo commanders noted that you had to tilt the LM *way*
over to get substantial motion going -- it wasn't at all like a helicopter
in that respect. (Note that the LLRVs and LLTVs had their big G-canceling
jet engine on gimbals, precisely so tilting the vehicle *didn't* give you
any thrust vectoring on it, to simulate this.)

Note also that major revisions were made to the LM control software
between Apollo 9 and Apollo 10, because in-space testing on Apollo 9
exposed some serious problems in the autopilot algorithms used for manual
flying. Newtonian physics it may be, but it's not at all straightforward
when applied in large doses. :-)

...a helicopter
would make a far safer alternative, and probably fly far more like the
actual lander than the Harrier would.

Neither one is a very good simulation, unless perhaps you apply a generous
dose of fly-by-wire to change the handling.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

Pat Flannery wrote:



wrote:

I was wondering what the groups thinks of the need to build an
"LLTV 2.0" to train future Moon bound astronauts, or has simulation
advanced to a state where such an effort is superfluous and needlessly
risky?

Given the state of simulation systems today, perhaps something like LLTV
wouldn't be needed; still, I suspect to help the pilots really get a
feel for it, a future Lunar landing simulator might use not the regular
hydraulic-legged motion base but perhaps a system based on something
like a really really friggin' huge air-hockey table(?).

--

..

"Though I could not caution all, I yet may warn a few:
Don't lend your hand to raise no flag atop no ship of fools!"

--grateful dead.
__________________________________________________ _____________
Mike Flugennock, flugennock at sinkers dot org
"Mikey'zine": dubya dubya dubya dot sinkers dot org