Margaritifer Basin (Margaritifer Trilogy Book 1) (23 page)

Abby took his hand with a look of
astonishment. “No, Master Chief, the pleasure is all mine. Jeff… uh, Captain
Grey, was regaling me of your adventures in Kuwait all the way down here. He
neglected to mention that you’d be here.”

“Ma’am, the Captain tends to take
some poetic license with the embellishments, if you know what I mean?” He
winked at her.

Abby smiled. “Be that as it may,
it’s a real pleasure Master Chief.”

“Alright, alright.” Jeff pointed to
the auditorium door. “Shall we?”

The Master Chief showed them to a
couple reserved seats up front and returned to the back of the room.

Looking at the stage, Abby leaned
to Jeff. “Who’s the four-star?”

“Admiral Gaylord, Pac Fleet.”

“Pac Fleet here for a Captain’s
retirement? Wow.”

“Yeah, Dillard’s big medicine, and
they know each other.”

“You ever meet him?”

“No.”

Abby looked around. “I don’t think
I’ve ever seen this much brass in one room before.”

“Yeah, anymore and the place might
sink.”

Jeff clinked beer glasses with
Ralph Dillard. “To retirement.”

Ralph smiled and nodded. “Amen to
that.”

“Twenty-six years, hell of a
career.”

“Hell of a long twenty-six years.”

“Yeah, I’ll bet. But I’ll tell you,
Ralph, there’s something about the image of the C.O. of SEAL Team 3 on a farm
in New Hampshire that just don’t seem right.”

“God Jeff, I’m lookin’ forward to
it. Finally, the quiet life.”

“You really don’t think you’d make
flag?”

Ralph laughed. “Shit, you know as
well as I do that about one in a thousand Special Forces officers get stars. I’m
not gonna hang around to watch myself get passed over for O-7.” He shook his
head. “I don’t want to go out that way.”

“Can’t say as I blame you. But
hell, Ralph, anyone that’s worn that trident on their uniform for as long as
you have deserves stars.”

Ralph shrugged. “Maybe, maybe not.
Anyway, you and I don’t make the rules.”

Jeff nodded. “That’s a fact. Well,
at least we’ll be pretty close again.”

“Yeah, how far is it to your
place?”

“From southern New Hampshire? I
dunno, maybe a three hour drive. You got an airport up there?”

“Yeah, there’s one just south of
Keene, about ten miles from us.”

“Well hell, it’s probably only
about a half hour by air.”

“That’s right, you’ve got a jet
don’t you, you rich bastard.”

Jeff chuckled. “Yeah. Wow, what a
trip this is.”

“You sure you want to do this?”

“Yeah, why the hell not? What else
have I got to do with the rest of my life?”

“You do this and the rest of your
life may be brief.”

“You think anybody’d miss me?”

“Yeah, Marilyn and me.”

“Anybody else?”

Ralph shook his head. “No, not that
I can think of.” He glanced toward the bar.

Jeff followed his gaze and spotted
Abby, surrounded by half a dozen SEAL officers. He grinned.

“I thought this was my party, but
Abby’s quite the attraction.”

“Ralph, she’s a lot better looking
than you.”

“No shit.” He stared at her for a
moment. “There’s something about her. She has a strength.”

“Uh huh.”

“Sure could of used somebody like
her on a SEAL team a few times.”

Jeff nodded. “If ever there was a
woman that could have not only made it through the pipeline, but put all the
boys to shame, you’re looking at her.”

“Perhaps
she
would miss you,
Jeff.”

“Maybe. But if I go, she’ll
probably go with me.”

“That would be a shame.”

Jeff took a long drink of beer and
rapped the table with his glass. “Yes it would.”

Sunday, August 5,
2012 (T minus 1325 days)

It was ten p.m. and Jeff yawned and rubbed his eyes, “Gabe,
it’s been a long day. Do we have to do this right now?”

“Why? You have a date?”

“Not for a few more hours. What have you got?”

“Let’s start
with the easy part.”

Jeff took a seat at the conference table. “Okay, fire
away.”

“On the outbound trip, there’s no margin for error on the
SPS fuel. Simulations indicate we’ll be running on fumes when we arrive in
orbit. That’s a bit disconcerting.”

“Yeah, I know. But, if the minimum wasn’t good enough, it
wouldn’t be the minimum.”

“Yes, I’ve heard that before. Still…”

“What do you propose?”

“That following TMI, we reduce our mass by getting rid of
anything we won’t need from then on. The EDS would be my first choice.”

“Well sure, but we’ll need that leftover O
₂
and
H
₂
if we’re forced to abort the landing and make a powered swing-by
and return home, and we have no place else to put it.”

“Yes, but not all of it. We should vent all but… the
minimum.”

“Okay, that makes sense. Check with Sue and get some
numbers.”

“Alright.”

“What else?”

“I don’t know. Non-recyclable waste?”

Jeff frowned. “Oh god, I hate to do that and just add more
clutter to space.”

“Yes, I know but…”

“Yeah. I can’t imagine that’s gonna amount to a whole lot,
particularly if we’re incinerating it.”

Gabe shrugged. “No, probably not, but it’s something.”

“See if you can come up with a number.”

“Okay. Is there anything else you can think of?”

Jeff sighed. “God, at this hour I’m not sure I’m capable of
rational thought. Um, let me think.” He stared at the table and scratched his
head for a minute, then laughed.

“What?”

“Oh, you’re gonna love this.”

“Uh oh.”

“Yeah. Speaking of the EDS, we’re not going to need the J-2
again, just the fuel and oxidizer tanks.”

Gabe gasped. “Oh my god, are you serious?”

“Well, immediately following TMI that engine is just 3600
pounds of useless junk.”

“Disconnect a J-2 and all its plumbing in space? Can that
even be done?”

“I dunno. Take a look at the S-IVB schematics and see. And,
since we haven’t built the things yet, there may be a way to engineer it to
make it easier. I dunno, maybe some adapter fitted with explosive bolts so we
don’t actually have to go outside and do it. Think about it.”

She shook her head. “Okay.”

Jeff grinned. “Hey, you asked.”

“Yeah.”

He held up a finger. “Ah, here’s something else that came
to mind a while back when I was reading the original CSM documentation. In the
original service modules the fuel cells and associated O
₂
and H
₂
tanks were all located in Sector 4. What was in Sector 1?”

Gabe cast him a puzzled frown. “Um, nothing.”

“Good grief, I know something you don’t.” He smiled and
mused, “Hold on a second, I need to savor this for a moment.”

She glared at him and tapped her fingernails on the table.
“Any time now.”

“No, not ‘nothing’. That sector was loaded with ballast to
offset the mass of Sector 4. Around 1500 pounds, as I recall.”

“And your point is?”

“Well, with tanks, we could probably get another 1200 or
1300 pounds of fuel in there. That’s only around 3%, but it might just give us
the breathing room you want.”

“Yes, but if we used that fuel, it would throw off the
module’s center of gravity.”

“True, but would you rather deal with a minor wobble, or
run out of fuel?”

“Hmmm, point conceded.”

He grinned. “Okay, well, take a look at it. In the
meantime, I’ll think on the matter and see if there’s anything else. So, is
that it?”

“Um, no.”

“What else?”

Gabe smiled politely. “Now comes the hard part.”

Jeff groaned, “Oh great.”

“First, allow me to say that, for an amateur, I’m really
impressed with your work. You did a lot in a very short period of time, you
have a good grasp of the subject matter, and you’ve got some interesting and
original ideas. I really am impressed.”

He returned her smile. “Um, thanks. But, uh, you’re
buttering me up for something. I feel the other shoe is about to drop.”

“Uh, yes.”

“What’d I do wrong?”

“Well, it has to do with the return trip.”

“What about it?”

“A couple things. First, you specify 31,500 pounds of N
₂
O
₄
and Aerozine-50 to refuel the service module, but you can’t burn nearly that
much so you can eliminate around 18,500 pounds of it.”

“Why can’t I burn that much?”

“Because an AJ-10-137 has a service life of about 750
seconds. Following orbital insertion that engine is only going to have around
185 seconds of life left in it – at best – before it devours itself. Why take
that much fuel when 60 percent of it can’t be used?”

He frowned. “Um, crap. I was counting on that for part of
the TEI Delta-V.”

“Yes, which brings us to part two. Um, I like your idea of
using a Centaur modified to burn hypergolic fuel as a return booster. That’s
interesting, and I think… doable. However, your return dates call for a Delta-V
of 3,280 meters per second. You can’t get anywhere near that with the mass of
this ship and that booster.”

“Wait a minute… the Rocket Equation says I can. It’s
obviously not accurate down to the meter per second and pound, but it’s in the
ballpark, and shows about 16% to spare.”

“Yes, but there is a wee problem with your math.”

“I didn’t do the math, the computer did.”

“Yes, but garbage in, garbage out. Your numbers are
correct, but only if the booster is fueled with LH
₂
and LOX, not if
it’s fueled with N
₂
O
₄
and Aerozine-50. You used the wrong
exhaust velocity. You’re short by a thousand meters per second.”

He slapped his forehead. “Holy shit! Are you kidding me?”

“Sorry, no. You’re going to need a much bigger booster. And
you can’t rely on the service module SPS, because you’ll need its remaining
life and fuel for mid-course corrections and re-entry alignment. So the booster
will have to do the entire job of getting us into Trans-Earth Injection.”

“How much bigger?”

“Oh, I don’t know, at least twice the size of what you had
in mind.”

“Twice?”

“Yes. Off the top of my head, I’d say somewhere in the
neighborhood of 115,000 pounds of fuel, and even that is with certain
qualifications.”

“What kind of qualifications.”

“Well, first I would suggest using a different fuel.”

“What?”

“RP-1 and LOX. It gives you a better exhaust velocity, it’s
cheaper, and all you need to do is figure out how to keep the RP-1 from
freezing for two years. Further, it’s in wide use and there’s probably an
available rocket stage out there somewhere that will come very close to what we
need. If nothing else, we could probably talk with SpaceX about having them
construct a Merlin-based stage to do the job.”

Jeff shrugged. “Okay, that doesn’t sound so bad.”

Gabe smiled. “No, except that still doesn’t get us there.
We need a lower Delta-V.”

“Um, I didn’t think Delta-V had a dial adjustment.”

“Well, it does in a sense.”

“What?”

“Change the return trip dates.”

“To what?”

“I see why you picked those dates; it gives us the longest
stay on Mars and a comparatively short, 179-day, return transit – for which I’m
sure we would all be appreciative when the time comes. However, as I said, that
transit calls for a Delta-V of 3,280 meters per second. For that, you’ll need a
booster the size of an S-IVB. So, what I propose is instead of departing on May
6
^th
, we leave on March 14
^th
for a 212-day transit,
arriving home on October 12
^th
, instead of November 1
^st
.
Okay, yes, we’ll have to spend an additional 33 days in space but, on the other
hand, we will get home two weeks earlier, not to mention spending a month and a
half less on Mars. But, out of a year and a half stay, that’s probably not
statistically significant. And, that transit only requires a 2,468 meter per
second Delta-V, which is much easier to achieve.”

“You sure?”

Gabe canted her head and glared at him.

“Sorry. Alright, so with your super-sized Centaur and date
change, we can make it home?”

“Yes, assuming we can figure out how to get the thing to
Mars in the first place.”

“Um, 115,000 is within a Falcon Heavy’s payload to LEO, and
it’s no challenge at all for an EDS to put that mass into TMI. What’s the
problem?”

“Getting it into orbit around Mars.”

Jeff frowned. “We use an aerocapture. We’ve already talked
about that.”

“Yes, we have. But we have not talked about attempting to
aerocapture nearly 60 tons. I’m not the least bit convinced that’s even
possible. For starters, you’ll have to dip it so far into the atmosphere it’ll
probably be kicking up sand as it goes by. Second, even if you can capture it
into orbit, that orbit is going to by utterly awful. We’ll never be able to get
to it.”