"Space: 1999" Eagle: Realistic?

On Thu, 08 Jul 2004 00:45:13 +0000, MattWriter wrote:

I saw a pic today of the Eagle from the old Space: 1999 TV series. While the
series' premise was ludicrous, it always seemed to me the modular Eagle
vehicles were well thought out.

It's a bit better than Thunderbird 2, its spiritual antecedent

It didn't look like there was much propellant storage,

Just imagine that the fuel is in the landing leg pods. The landing legs
were originally intended to be retractable, but the money to implement
that was never there. So let's make a virtue of necessity and use the
space in the leg pods for the fuel

but otherwise the Eagle seemed a fine lunar/L-1 utility vehicle, with
its changeable mission pods (I suspect the production designer took
that from the old Sikorsky SH-64 Skycrane helicopter)

I don't think Brian Johnson ever mentioned that particular vehicle in
relationship to the Eagle, but he is definitely an aviation buff.

its practical layout (no climbing down to the moon from the top of a
"wedding cake" lander needed), etc.

Operating in 1/6th or zero gee it's not much of a worry, and the "stacked
design", or tail sitter, offers serious engineering advantages.

Brian Johnson, the original designer of the Eagle, traces the original
concept back to 1965 when he was working on 2001 and especially the
Moonbus. He thought the concept of the Moonbus needed a better design
and drew up an alternative version on his own. He hung on to the concept
until he was hired for Space:1999 by Gerry Anderson.

But when he and his crew actually finalized and implented the Eagle design
he went strictly for filming practicality and onscreen functionality...
not engineering feasibility or scientific versimilitude.

_That's_ why Space:1999 had such wonderful models and effects for its
time and for its budget... and why it all falls apart if you look at it
too closely.

When talking of any SF video design you must lay out what is given about
the vehicle and its environment. So: The Eagle, or Moon Utility Transport
as it was originally called, became not a lunar surface passeger
transport but instead a vehicle designed for Lunar, space, and asteroid
operations. It hauls people, cargo, and a variety of specialty modules
hither and yon.

(Asteroid operations by Johnson's own word: he cringed at the "Moon
blown out of orbit" idiocy and tried to get Alpha at least relocated to
a large asteroid... )

Timeframe: "near future" (ha!)
Power source: SF-style fusion.
Thrust vectors: 2 one vertical for hover engines, one horizontal for
main engines.
Life Support: might be possible to tuck it away here and there.
Eagles were large for their _actual_ passenger volume.
Atmosphereic Operation : ignore.
Artificial Gravity: ignore.

The Eagle: front to back:

Chapter 1: "Invasion Of The Space Eaters"

On closer examination the command module doesn't make much sense with
its 4 huge symmetrical anti-glare insets for only two viewports. Brian
Johnson had originally envisioned that the cockpit would have had four
viewports to match the four insets. But even as production progressed
and it became obvious that there would only be two viewports Johnson
kept the lower insets because he liked the design. But even granting
some engineering necessity for a command module shaped like a flattened
plum bob, and even imagining that the lower pair of insets are for optical
nav instruments and not eyeballs... the insets are just too big and
there's too many of them.

Not much of a view... with a cost. Too much wasted space:
http://www.smallartworks.ca/Articles/Restoration/r1.jpg

Johnson had plans for a third-season redesign that would have had only
the upper two insets.

Eagle modeling fans are of course familiar with the discrepancies
in size and shape between the exterior shots of the vehicle and the sets
used to portray the interior, but that's easily forgiven as Johnson
had zero input in the set designs and the fans make do with the best
scaling that fits.

But even granting the most gracious scaling there is _no_ room for the
sliding hatches (designed after the ubiquitous Monbase doors) seen in the
Eagle sets between modules... they cannot exist. The fact that these
hatches are externally visible in some shots and obviously have no
way to hinge open and no way to slide open is one of the Eagle failings
that can't be excused away.

The hatch that should not be... :
http://www.starshipmodeler.com/tech/elab4.jpg

Moving back from the command module, the little area between it and the
payload module area would seem useful as an airlock and storage area, no
problems there as long as you ignore those sliding hatches.

But in this area we run into another problem ... the hover engines.

They're big. They're bad. They're _too_ big for the job and since they
are overly ornate and hollow they imply motors above them... motors which
would decidly block the pathways between modules and stick up from the
floor in the middle of the passenger module.

Hatch and hover thrusters... too much in too little space:
http://www.starshipmodeler.com/tech/epass6.jpg

Just to double-check:
http://www.smallartworks.ca/Articles...tion/12&13.jpg

Passenger pod bottom view... and those huge thrusters redux:
http://www.smallartworks.ca/Articles/Restoration/41.jpg

Chapter 2: "A weak-spined individual..."

Moving back to the payload module area we run into the spine that holds
the Eagle together. While certainly not the most egregious offender
engineering-wise it does have problems. The spine is both overdesigned
and not well designed. Overdesigned, overly thick and strong, because its
practical purpose was to hold a large model and often awkwardly-weighted
modules together under studio working conditions in Earth's gravity. Not
well designed because it didn't take advantage of known engineering
techniques to strengthen the design.

When erecting scaffolds, power line towers, or any other skeletal
girderwork it's best to use triangles as your basic building units.
The Eagle spine is instead built as a 4-sided trapezoidal enclosure and
while the spine enclosure does have angled braces on its short sides the
wider spaced top and bottom sides just have welded rectangular sections...
no angular bracing. It's weak. And the stories of the bracing twisting and
breaking during filming, even as overdesigned as it was, would seem to
back that up.

The angles are all... wrong...
http://www.geocities.com/CapeCanaver...le/eagnew9.jpg
http://www.smallartworks.ca/Articles/Restoration/7.jpg

Chapter 3: "Space Module"

Now we come to the payload modules... the reason for the Eagle's
existence. The concept is that the very purpose and mission of the Eagle
can be changed by swapping out payload modules. The module is envisioned
as something that can be loaded or unloaded onto an Eagle with relative
ease.

Given tech that's anywhere in the near-future that would be a diffilcult
prospect if the module had more than the simple power and data connections
with the rest of the Eagle. As for the passenger module the thought of
sealing two life-support systems together safely and securely in the
indicated space in a short period of time would give designers
interesting headaches... and possibly fatal results for the passengers.

In fact the only reason for using the Eagle design, with its multitudes
of engines pointing in different directions, is the imagined ease of
module replacement. But if you're actually building for lunar or
microgravity environments then module changes need be no harder for
a simpler, bettter-designred tail sitter than for an Eagle. Between a
crane and one or two robot arms modules could be changed out and
replaced with relative ease by a tail sitter.

Although the Eagle w/ module might be designed to be stronger than an
Eagle w/ just the spine you still have the fact that many of the more
"heroic" duties of the Eagle pods, winching up and hauling nuclear
waste cans or crashed Eagle parts, could as well be done with a simpler,
stronger tail-sitting lander _without_ the Eagle's multitudde of
variously functioned engines.

I can't resist asking: did anyone in NASA or industry ever do a serious
analysis of this design for real life?

Interesting concept

There are plenty of websites on the show and Eagle models, but no
detailed expert commentary or analysis on the
design.

That's because while it's a fun design, and one of my favorites, it
cannot be taken seriously.

Matt Bille
)
OPINIONS IN ALL POSTS ARE SOLELY THOSE OF A RANDOM SELECTION OF CATGIRLS.

--
Chuck Stewart
"Anime-style catgirls: Threat? Menace? Or just studying algebra?"