Global Flyer

In article ,
Rich S. wrote:
"Robert Bonomi" wrote in message
...

Well, *except* for the fact that the U.S. government was already a
signatory
to an international treaty _disclaiming_ any such claims of territorial
ownership "in space".

But what I *really* wanted to explore was design ideas for a homebuilt
"airborne" Moon vehicle.

Here's the scene: You're living on Luna, having retired from ______ (fill in
blanks at your pleasure). It's the year ____ and low-gravity retirement has
become the "in" thing. You live longer, the old aches and pains are less,
etc. Your Social Security private trust fund has built up to the point that
you just *have* to start spending some of it! The one thing you miss since
moving out here is roaring around in your homebuilt on Saturday afternoons.
So, absent any regulation to the contrary, you decide to build a Lunar
replacement.

First thing to decide on is a name for the critter. Hmmm..... Moonraker
sounds appropriate. Wonder if anybody has used that one? Oh heck with that,
let's get on to the design parameters.

Seats - One, two???

Absolute requirement: one-plus.

Pressurization - (?) if not, then a big enough seat to accommodate a space
suit.

Pressurization introduces *lots* of complications -- seals, O2 mixture supply,
etc. Not to mention what it does to weight and balance.

Range - There's fuel and air caches every 1,800 miles, so let's add ~10% and
say 2,000 miles.

Optimist! "Origin to primary, divert to secondary, plus 'holding' time"
plus (at least) 10% of _that_ total. If you want to survive the 1st emergency,
that is. I get a requirement of about 4300mi (minimum)

Speed - Let's say 600 knots. (What I'm doing is multiplying typical terran
specs by 6. Why? I dunno)

Something to do with the underlying gravity of the situation?

Payload - (?) We can let the Mass/Weight guys duke that one out.

Visible means of support (Lift) - Wonder if NASA has an airfoil for an
airless environment? If not, we'll have to come up with something. I
wouldn't want to go ballistic - it's not as much fun as low & slow.

They do (see "solar sail", but it's not practical to deploy on Luna, due to
the high gravity there.

Thrust - Open for suggestions. . .

"We can always throw rocks."

"Ballistic" glider lets you leave the engine on the ground, at the take-off
site.

Primary source of power - Anybody got a design for something better than a
Chinese sparkler?

There's always NASA's "Orion" design.

Scaling might pose some *serious* difficulties, however.

"Robert Bonomi" wrote in message
...
In article ,

Pressurization introduces *lots* of complications -- seals, O2 mixture
supply,
etc. Not to mention what it does to weight and balance.

We'll let the spacesuit designers worry about that one, then.
"Give me one Moonsuit, Mark IV and a forty watt phased plasma rifle, please"

Range - There's fuel and air caches every 1,800 miles, so let's add ~10%
and
say 2,000 miles.

Optimist! "Origin to primary, divert to secondary, plus 'holding' time"
plus (at least) 10% of _that_ total. If you want to survive the 1st
emergency,
that is. I get a requirement of about 4300mi (minimum)

Uh-uh. No weather diversions necessary. Note: Sport Pilots may not fly at
night.

Speed - Let's say 600 knots. (What I'm doing is multiplying typical terran
specs by 6. Why? I dunno)

Something to do with the underlying gravity of the situation?

Snicker

"Ballistic" glider lets you leave the engine on the ground, at the
take-off
site.

"Glider"????

Primary source of power - Anybody got a design for something better than a
Chinese sparkler?

There's always NASA's "Orion" design.

Scaling might pose some *serious* difficulties, however.

My Citizen watch has a "Forever" battery and only needs an occasional burst
of sunlight - can we scale that up?

Rich S.

On Sat, 5 Mar 2005 07:29:57 -0800, "Rich S."
wrote:

But what I *really* wanted to explore was design ideas for a homebuilt
"airborne" Moon vehicle.

Here's the scene: You're living on Luna, having retired from ______ (fill in
blanks at your pleasure). It's the year ____ and low-gravity retirement has
become the "in" thing. You live longer, the old aches and pains are less,
etc. Your Social Security private trust fund has built up to the point that
you just *have* to start spending some of it! The one thing you miss since
moving out here is roaring around in your homebuilt on Saturday afternoons.
So, absent any regulation to the contrary, you decide to build a Lunar
replacement.

"Moon Zero Two", 1969, starring James Olson.

First thing to decide on is a name for the critter. Hmmm..... Moonraker
sounds appropriate. Wonder if anybody has used that one?

Been there, done that:

http://www.bowersflybaby.com/stories/leoraker.JPG

Oh heck with that,
let's get on to the design parameters.

Seats - One, two???

With a weight increase, the amount of fuel needed increases disproportionately.
Also, if you add a second seat, you're always going to have to have a body or
ballast in the spot to keep the beast in balance.

Pressurization - (?) if not, then a big enough seat to accommodate a space
suit.

It's tough to do precision work in a space suit. The gloves give you next to no
tactile feel...in fact, the fingertips are usually covered with hard rubber
shells.

http://www.hightechscience.org/orlan_space_glove.htm

You're not going to be able to work a keyboard, and if you have buttons and
whatnot to push, they're going to have to be well separated to ensure you don't
punch the wrong one. It's gonna be tough to fly without a pressurized cabin.

But...again, pressurization is going to add a lot of weight. You not only need
a pressure hull with windows and an openable door, but you're going to need the
typical air conditioning functions such as oxygen replacement, CO2 removal,
humidity control, etc. Since these problems are ALREADY solved with a space
suit, you might as well just go open cockpit...after all, you'll need a space
suit onboard anyway for the walk from the landing field to the cafe for that
$100,000,000 hamburger.

Hmmmm, single seat, open cockpit. The Luna Baby? :-)

Range - There's fuel and air caches every 1,800 miles, so let's add ~10% and
say 2,000 miles.

2000 miles is about 1/3 the way around the entire moon...2/3rds the maximum
distance you'd want to fly, anyway.

It's been years since I did any sort of lunar orbit work (and even that was only
for a week or so...damned if I can even remember what program it was). To get
some answers, I modified one of my orbit analysis tools to do Moon orbits
(changed the values for G, planetary radius, and gravitational constant). In
other words, lotsa approximations here.

For a 2000-mile ballistic trajectory on the Moon that gets at least 10 NM high,
you'll need about 5000 FPS of acceleration. And if you want to touch down with
near-zero speed, you'll need about the same for deceleration. We'll call it a
total of 10,000 FPS. Flight time less than a half hour, including accel and
decel.

Let's assume an open-cockpit single-seater. Call it 200 lbs for the pilot,
another 100 lbs for his suit, 500 pounds of airframe, 20 pounds of avionics, and
50 pounds for batteries and life support supplied. Let's assume our rocket fuel
has a specific impulse of 250 seconds. That's a dry weight of about 870 pounds.

The fuel comes out to another 2150 pounds.

Like Robert said, though, we could use a mass driver or other ground-based
system to throw the vehicle, and just rely on onboard fuel to land. This drops
the required onboard fuel to about 750 pounds. Not too bad.

Speed - Let's say 600 knots. (What I'm doing is multiplying typical terran
specs by 6. Why? I dunno)

Visible means of support (Lift) - Wonder if NASA has an airfoil for an
airless environment? If not, we'll have to come up with something. I
wouldn't want to go ballistic - it's not as much fun as low & slow.

Yep, ballistic wouldn't be much fun. You want a "Hollywood" moon flight: Take
off, climb to a given altitude, cruise at that altitude through the entire
flight, then descend to land.

If we don't have antigravity, what's it going to take?

Let's look at the cruise speed first. 600 knots is about 1000 FPS, and we'll
need both acceleration and deceleration fuel. Total 2000 FPS. Give it another
500 FPS to cover the climb (coming down is free!).

To fly at the constant altitude, we'll need constant downward thrust to
counteract the force of gravity. Since we're flying 2000 NM at 600 knots, we
have to do this for about 3.3 hours. Call it four hours with VFR reserves. :-)

So...we have to burn our downward thrusters for four hours. "G" on the Moon is
about 5.6 ft/Sec^2. We'd need to burn the same to counter that. Total
acceleration required is 5.6 ft/sec^2 x 4 hours x 3600 seconds/hour... about
80,000 FPS, about sixteen times more than a ballistic S/C using a mass driver
for launch, and, as a point of interest, almost three times what a spacecraft
launch from the *Earth* needs. With the accel/decel Delta-V, our 870-pound
spacecraft requires 24.9 *million* pounds of fuel.

C'mon guys. There's got to be another Rutan out there. What are we going to
do when he's history?

Live far more boring lives, I reckon....

Ron Wanttaja

In article ,
Rich S. wrote:
"Robert Bonomi" wrote in message
...
In article ,

Pressurization introduces *lots* of complications -- seals, O2 mixture
supply,
etc. Not to mention what it does to weight and balance.

We'll let the spacesuit designers worry about that one, then.
"Give me one Moonsuit, Mark IV and a forty watt phased plasma rifle, please"

Woops! You'll have to settle for the EnergyStar compliant 34 watt one.

Range - There's fuel and air caches every 1,800 miles, so let's add ~10%
and
say 2,000 miles.

Optimist! "Origin to primary, divert to secondary, plus 'holding' time"
plus (at least) 10% of _that_ total. If you want to survive the 1st
emergency,
that is. I get a requirement of about 4300mi (minimum)

Uh-uh. No weather diversions necessary. Note: Sport Pilots may not fly at
night.

Moon-quake, Solar flare, "Deck is fouled", I can think of a bunch of reasons
that 'divert to alternate' might be required.

Speed - Let's say 600 knots. (What I'm doing is multiplying typical terran
specs by 6. Why? I dunno)

Something to do with the underlying gravity of the situation?

Snicker

No, no. That's a *Mars* bar. This is Luna. And it should be *obvious*
that "Almond Joy" is the appropriate one -- "Sometimes you feel like a nut"
*DEFINITELY* describes this 'food for thought'.

(Don't blame me if you don't like the answer. It was _your_ question, after
all.


"Ballistic" glider lets you leave the engine on the ground, at the
take-off
site.

"Glider"????

You don't really think a *PARACHUTE* will work, do you ? grin

But, yeah, "glider" -- for lack of a better term. At the landing site,
a *BIG* ramp -- with the _upper_ part conforming to the ballistic trajectory
you launched into. You have on-board 'maneuvering' thrusters, to tweak
you path to the _exact_ ramp trajectory -- a GCA "glide slope" with a
*vengeance*. You touch down on the ramp, and roll out, possible friction
brakes, possible aircraft-carrier type snubbing cable.

(I just realized that this is a _ground-based_ 'ballistic recovery system'!


Of course, this system makes "divert to alternate" a physical impossibility.
Unless you carry a *ridiculous* amount of 'delta v' on board.

Primary source of power - Anybody got a design for something better than a
Chinese sparkler?

There's always NASA's "Orion" design.

Scaling might pose some *serious* difficulties, however.

My Citizen watch has a "Forever" battery and only needs an occasional burst
of sunlight - can we scale that up?

You can *try*, but I suggest that -first- you calculate the energy-density
of that system. then contemplate the mass requirements, _just_ to power
your "forty watt plasma rifle" -- let alone any on-board flight controls,
instrumentation, life-support system, etc.

Rich S. wrote:
"Robert Bonomi" wrote in message
Optimist! "Origin to primary, divert to secondary, plus 'holding' time"
plus (at least) 10% of _that_ total. If you want to survive the 1st
emergency,
that is. I get a requirement of about 4300mi (minimum)


Uh-uh. No weather diversions necessary. Note: Sport Pilots may not fly at
night.

Wait a minute there, the lunar days are about 28 times as long as
ours. Spending all that time on the dark side of the moon may make
currency requirements difficult- say you don't log enough takeoffs or
landings for an entire lunar day, plus the prior and following lunar
nights, do the math, it's a long time and that's gonna be tough!

Ron Wanttaja wrote:

On Sat, 5 Mar 2005 07:29:57 -0800, "Rich S."
wrote:


But what I *really* wanted to explore was design ideas for a homebuilt
"airborne" Moon vehicle.

Here's the scene: You're living on Luna, having retired from ______ (fill in
blanks at your pleasure). It's the year ____ and low-gravity retirement has
become the "in" thing. You live longer, the old aches and pains are less,
etc. Your Social Security private trust fund has built up to the point that
you just *have* to start spending some of it! The one thing you miss since
moving out here is roaring around in your homebuilt on Saturday afternoons.
So, absent any regulation to the contrary, you decide to build a Lunar
replacement.


"Moon Zero Two", 1969, starring James Olson.


First thing to decide on is a name for the critter. Hmmm..... Moonraker
sounds appropriate. Wonder if anybody has used that one?


Been there, done that:

http://www.bowersflybaby.com/stories/leoraker.JPG


Oh heck with that,
let's get on to the design parameters.

Seats - One, two???


With a weight increase, the amount of fuel needed increases disproportionately.
Also, if you add a second seat, you're always going to have to have a body or
ballast in the spot to keep the beast in balance.


Pressurization - (?) if not, then a big enough seat to accommodate a space
suit.


It's tough to do precision work in a space suit. The gloves give you next to no
tactile feel...in fact, the fingertips are usually covered with hard rubber
shells.

http://www.hightechscience.org/orlan_space_glove.htm

You're not going to be able to work a keyboard, and if you have buttons and
whatnot to push, they're going to have to be well separated to ensure you don't
punch the wrong one. It's gonna be tough to fly without a pressurized cabin.

But...again, pressurization is going to add a lot of weight. You not only need
a pressure hull with windows and an openable door, but you're going to need the
typical air conditioning functions such as oxygen replacement, CO2 removal,
humidity control, etc. Since these problems are ALREADY solved with a space
suit, you might as well just go open cockpit...after all, you'll need a space
suit onboard anyway for the walk from the landing field to the cafe for that
$100,000,000 hamburger.

Hmmmm, single seat, open cockpit. The Luna Baby? :-)


Range - There's fuel and air caches every 1,800 miles, so let's add ~10% and
say 2,000 miles.


2000 miles is about 1/3 the way around the entire moon...2/3rds the maximum
distance you'd want to fly, anyway.

It's been years since I did any sort of lunar orbit work (and even that was only
for a week or so...damned if I can even remember what program it was). To get
some answers, I modified one of my orbit analysis tools to do Moon orbits
(changed the values for G, planetary radius, and gravitational constant). In
other words, lotsa approximations here.

For a 2000-mile ballistic trajectory on the Moon that gets at least 10 NM high,
you'll need about 5000 FPS of acceleration. And if you want to touch down with
near-zero speed, you'll need about the same for deceleration. We'll call it a
total of 10,000 FPS. Flight time less than a half hour, including accel and
decel.

Let's assume an open-cockpit single-seater. Call it 200 lbs for the pilot,
another 100 lbs for his suit, 500 pounds of airframe, 20 pounds of avionics, and
50 pounds for batteries and life support supplied. Let's assume our rocket fuel
has a specific impulse of 250 seconds. That's a dry weight of about 870 pounds.

The fuel comes out to another 2150 pounds.

Like Robert said, though, we could use a mass driver or other ground-based
system to throw the vehicle, and just rely on onboard fuel to land. This drops
the required onboard fuel to about 750 pounds. Not too bad.


Speed - Let's say 600 knots. (What I'm doing is multiplying typical terran
specs by 6. Why? I dunno)

Visible means of support (Lift) - Wonder if NASA has an airfoil for an
airless environment? If not, we'll have to come up with something. I
wouldn't want to go ballistic - it's not as much fun as low & slow.


Yep, ballistic wouldn't be much fun. You want a "Hollywood" moon flight: Take
off, climb to a given altitude, cruise at that altitude through the entire
flight, then descend to land.

If we don't have antigravity, what's it going to take?

Let's look at the cruise speed first. 600 knots is about 1000 FPS, and we'll
need both acceleration and deceleration fuel. Total 2000 FPS. Give it another
500 FPS to cover the climb (coming down is free!).

To fly at the constant altitude, we'll need constant downward thrust to
counteract the force of gravity. Since we're flying 2000 NM at 600 knots, we
have to do this for about 3.3 hours. Call it four hours with VFR reserves. :-)

So...we have to burn our downward thrusters for four hours. "G" on the Moon is
about 5.6 ft/Sec^2. We'd need to burn the same to counter that. Total
acceleration required is 5.6 ft/sec^2 x 4 hours x 3600 seconds/hour... about
80,000 FPS, about sixteen times more than a ballistic S/C using a mass driver
for launch, and, as a point of interest, almost three times what a spacecraft
launch from the *Earth* needs. With the accel/decel Delta-V, our 870-pound
spacecraft requires 24.9 *million* pounds of fuel.


C'mon guys. There's got to be another Rutan out there. What are we going to
do when he's history?


Live far more boring lives, I reckon....

Ron Wanttaja

Hey, they didn't do it that way in "2001 a Space Odyssey" when they
cruised across the surface ofthe moon in the moon bus.

Dan "who thinks Ron has shot down my dreams", U.S. Air Force, retired

On Sat, 05 Mar 2005 19:11:22 GMT, Ron Wanttaja
wrote:



Let's assume an open-cockpit single-seater. Call it 200 lbs for the pilot,
another 100 lbs for his suit, 500 pounds of airframe, 20 pounds of avionics, and
50 pounds for batteries and life support supplied. Let's assume our rocket fuel
has a specific impulse of 250 seconds. That's a dry weight of about 870 pounds.


forgive my iggorance.
are we talking earth pounds, moon pounds or mass?
and if we are talking mass is it roman catholic, anglican or
engineering?
you get that for ruining dreams :-)


what is actually needed is for someone to do a Wright Brothers on
gravity.
aviation would go another quantum leap forward if we could just negate
the aircraft weight without all that drag.
it is amazing that with all our progress we havent made one single
inroad into understanding or controlling gravity.

Star Wars episode 1, The phantom menace was shown on local telly last
night. I'm amazed at how correct the understanding of an antigravity
world was in that film.
Stealth (ok, antigravity liftoff, now how do we get thrust?) Pilot

"Ron Wanttaja" wrote in message
...

"Moon Zero Two", 1969, starring James Olson.

Ooh - I'll look that one up!

With a weight increase, the amount of fuel needed increases
disproportionately.
Also, if you add a second seat, you're always going to have to have a body
or
ballast in the spot to keep the beast in balance.

We'll just make the ship expandable. When you've got a passenger, just
unlatch it in the middle and pull the ends out - like you do with the dining
table when Grandma's coming.

You're not going to be able to work a keyboard, and if you have buttons
and
whatnot to push, they're going to have to be well separated to ensure you
don't
punch the wrong one. It's gonna be tough to fly without a pressurized
cabin.

Who sez the spacesuit can't have a keyboard- or even a joystick? Pull your
arms inside and start typing. 'Course the chest area would look like Jayne
Mansfield's.

2000 miles is about 1/3 the way around the entire moon...2/3rds the
maximum
distance you'd want to fly, anyway.

Hmmm... I forgot about how small the circumference is. Maybe 2,000 miles is
more than we need. There's bound to be other colonies less than 2K miles
apart.

Like Robert said, though, we could use a mass driver or other ground-based
system to throw the vehicle, and just rely on onboard fuel to land. This
drops
the required onboard fuel to about 750 pounds. Not too bad.

Naw - can't go for the ground based system. What if you want to stop for a
picnic on the shore of the Mare?

Yep, ballistic wouldn't be much fun. You want a "Hollywood" moon flight:
Take
off, climb to a given altitude, cruise at that altitude through the entire
flight, then descend to land.

If we don't have antigravity, what's it going to take?

Well, maybe we *do* have antigravity. After looking at your figures (not
that I understand them), did you say that 5,000 fps is orbital velocity at
10 NM MSL? If so, then what speed is orbital velocity at 1,000' MSL (Moon
Surface Level)? Cruising at that speed would obviate the need for constant
vertical thrust. Half that speed would require less constant vertical thrust
than a hover. If you could find a happy medium, perhaps a small fuel cell,
plutonium reactor, cold fusion motor, or bag of rocks and Hernadez's 98 mph
fast ball would do it.

C'mon guys. There's got to be another Rutan out there. What are we going
to
do when he's history?

Live far more boring lives, I reckon....

"May you live in interesting times"

Rich "Call Hazel Stone" S.

"Robert Bonomi" wrote in message
...
Moon-quake, Solar flare, "Deck is fouled", I can think of a bunch of
reasons
that 'divert to alternate' might be required.

Controllers on strike, Aliens on runway, Gotcha.

No, no. That's a *Mars* bar. This is Luna. And it should be *obvious*
that "Almond Joy" is the appropriate one -- "Sometimes you feel like a
nut"
*DEFINITELY* describes this 'food for thought'.

(Don't blame me if you don't like the answer. It was _your_ question,
after
all.

:O)

But, yeah, "glider" -- for lack of a better term. At the landing site,
a *BIG* ramp -- with the _upper_ part conforming to the ballistic
trajectory
you launched into. You have on-board 'maneuvering' thrusters, to tweak
you path to the _exact_ ramp trajectory -- a GCA "glide slope" with a
*vengeance*. You touch down on the ramp, and roll out, possible friction
brakes, possible aircraft-carrier type snubbing cable.

You been watching old Evel Knievel tapes I'll bet.

You can *try*, but I suggest that -first- you calculate the energy-density
of that system. then contemplate the mass requirements, _just_ to power
your "forty watt plasma rifle" -- let alone any on-board flight controls,
instrumentation, life-support system, etc.

Improvements in battery design have been ramping up so quickly in the past
few years that I fully expect to see a pink, drum-beating bunny on the Moon!

Rich S.

"Dan, U.S. Air Force, retired" wrote in message
news:rGsWd.24184$Sn6.22376@lakeread03...

Hey, they didn't do it that way in "2001 a Space Odyssey" when they
cruised across the surface ofthe moon in the moon bus.

Wasn't that a monorail or cable-suspended car?

Rich "running low on memory" S.