What follows is the read-me file I included with my latest release (to
OrbitHangar Downloads) of the 2008 Edition of the Firefly "Jumbo" Transport Grey Goose.... it serves as a kinda-sorta-tutorial on the vagaries of FF intra-system travel. I expect they'll take a day or two to approve it, but I'll provide a link in the "Fleet Announcements" section of the forum.
The link WILL DISAPPEAR by this Saturday, but you should be able to d/l it from OrbitHangar Downloads by then.
Cheers! Happy New Year!
ZCochrane
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(pasted from the read-me file, without all of the fancy .rtf fonts and such - the prettier version is in the 2008 Doc file)
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Firefly "Jumbo" Transport
"Grey Goose"
2008 Edition
by Jon Marcure & Shawn Beard
Welcome! The files and folders included in this archive are an Orbiter Spaceflight Simulator add-on (the main Orbiter webpage:
http://www.orbitersim.com/), the Firefly "Jumbo" Transport spacecraft. This add-on was inspired by the T.V. series Firefly, and the motion picture Serenity. It is loosely based on the vessel piloted by the main characters in the show and movie, and is not an accurate representation or copy of that ship. Rather, it is an interpretation of that vehicle, wonderfully realized visually by Jon Marcure, with some additional coding and suggestions from me. The last release of this Orbiter add-on was in 2006, and since then I've made some modifications to the flight model, .dll interface, and visual components. I hope you will find them pleasing.
First and foremost is a hearty "thank you!" to Jon Marcure for his generosity and patience while teaching me a great deal about Orbiter, and how to personalize it with our own creations. His love for all things sci-fi, his talent as a coder and visual model-making, and his willingness to let me play with his toys to learn a thing or three make me proud to call him my friend and mentor. His name is first on the credits because he's done 99% of the work, and my 1% contribution was simply to make them fly the way I think they should in Orbiter, and to offer out-of-the-box solutions to any knotty problems that may have arisen during the process. Learning how to do that fairly decently was a direct result of Jon showing me how this stuff works, and I will always appreciate it. Again, thanks!
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The actual specs and info needed to install and fly this futuristic craft are in the folder "FFJumbo2008\Doc\2006 Firefly Jumbo Read Me"; this is the original information Jon and I provided when it was released in 2006, and is still, for the most part, current. Any additional info or quasi-tutorials are included here in this document. Even so, here's a quick rundown ~
Installation:
Simply unzip the contents of this archive into your main Orbiter directory (the folder where "Orbiter.exe" resides). If you wish to uninstall the ship, you may simply delete the scenarios that reference it, as well as the "QJFF.dll" file within the "Modules" folder. If you are intent on removing ALL of the components from your Orbiter folder, you should probably open this archive, make a list of the files and folders contained herein, and manually delete their brothers and sisters, since I'm way too lazy to list them all here.
Key Controls:
Ctrl-F Extend/Retract cargo bay attachment post
Ctrl-G Open/Close cargo door
G Raise/Lower landing gear
J Extend port shuttle
K Extend starboard shuttle
Ctrl-J Release port shuttle
Ctrl-K Release starboard shuttle
(the following are NOT NumPad numeral-keys ~ they are ALPHA-numeric keys, above the letters of the keyboard)
1 Swivel the port engine nacelle forward
2 Swivel the port engine nacelle backward
3 Swivel the starboard engine nacelle forward
4 Swivel the starboard engine nacelle backward
5 swivel both nacelles forward
6 swivel both nacelles backward
7 set both nacelles automatically to forward position
8 set both nacelles automatically to hover position
9 set both nacelles automatically to reverse position
C Set engine thrust ONLY to normal (Firefly thrust factor NOT affected)
S Increases engine thrust ONLY to 3x normal (nearly 50 m/s/s with no cargo and a full fuel tank)
Ctrl-0 Reduce engine thrust to about 1/4 ~ also reduces Firefly thrust by 1/10th, approx. 100 m/s/s with full fuel, no cargo
0 Set engine thrust to normal (about 16.5 m/s/s with no cargo and a full fuel tank) ~ also sets Firefly thrust to normal
Ctrl-9 Sets Firefly thrust to 10x normal ~ approx. 10 km/s/s with full fuel, no cargo
Ctrl-8 Sets Firefly thrust to 100x normal ~ approx. 100 km/s/s with full fuel, no cargo
Ctrl-F12 ACTIVATES the Firefly Drive
F Forward (Cockpit) view
D Downward view (from docking port 2, just below the cockpit, useful for visually-aided landings on base pads)
B Backward view (think of it as an external camera, REVERSE VIEW, looking back over the top-right of the ship)
Navigation:
The key to successful and effective navigation with this version of the Firefly "Jumbo" Transport is taking your time to plan a bit, knowing where you are with relation to your origin and destination points, and proper propellant management. I used to zip around with this thing, giving it ridiculous amounts of thrust and nearly unlimited fuel resources. You know what? That just not any fun. Now, while keeping a high-sci-fi-factor associated with it's futuristic drive, it still has quite FINITE resources.
The top speed of this thing (considering if you want to turn around and slow it down again) is around 2500 km/sec ~ you can cover an A.U. in a little over 16 hours. Don't want to slow down? Good for you: with two Firefly-engine bursts, and less than 20% fuel left, you get to go speeding away at over 5000 km/sec ~ without any hope of coming back unless you hit Ctrl-Q to exit Orbiter and try again! Part of the reason for this is that Jon and I are developing another quite popular sci-fi addon, and it seemed important to me that a ship like the Grey Goose ought to be able to outrun what we're making IN THE SHORT RUN, but ultimately will be a part of it's fleet of ships that we are building to accompany it, this soon-to-be-released add-on. The Grey Goose has even been hard-coded in advance to simulate flying in formation with this anticipated add-on spacecraft (via attachments), and thus vicariously will enjoy the ability to traverse MUCH larger distances in MUCH shorter durations. The Firefly Transport can really go places on her own ~ but not like what she'll eventually be a part of. So bring a lunch when flying her.
There are some tips and tricks I can offer to give you a good first transplanetary experience flying this brick:
Save your fuel: when lifting off from Earth, use your main engines to get above 15 km alt. ASAP, then kill your mains, hit Ctrl-0 to reduce your Firefly thrust to 1/10th, and activate the drive, keeping your mains off. You'll get to high altitudes with a fraction of the propellant you would have used if you'd kept going with the mains alone.
Got a target? Make things easier for yourself. Sure, you could just point and thrust at 100 km/s/s, but your arrival will be sloppy and inaccurate because there's a difference in relative velocities and vectors - often terribly significant - between your ship and your target when you first set out. And you'll just waste more propellant when you do the corrections. Kill this first once you're well away from planetary bodies and other obstacles that might be in line for you to smack like the fist of God while you match velocities with your target.
Plan your arrival! You get two chances at maximum Firefly thrust - full thrust at (Ctrl-8) over 100 km/s/s, and then again when you turn ass-first to slow the hell down once you get there. Again, top speed on one FF burst is about 2500 km/s with full fuel and no cargo. Add to that the fact that one full maximum burn WILL eat up 40% of your fuel in about 24 seconds, and planning ceases to be an option. How to plan WHEN to FF-burn retrograde? Welp, you'll probably need a calculator with a square-root function, 'cause now I'm gonna get all Newtonion on your butt:
Acceleration is determined by thrust and mass. One of those variables I'll give you, and the other is easily obtainable from within Orbiter.
First off - at normal (Keyboard 0 "zero") thrust level - the Firefly Drive that I modified gives the Grey Goose almost exactly 1 km/s/s acceleration with 100% fuel and no cargo attached. And with those parameters (100% fuel + no cargo) I know that she weighs 149,001 kg.
After lifting off, leaving orbit, zipping around a bit, whatever ~ that mass has changed from using propellant. By how much? Easy to figure: Ctrl-I will bring up the inormation dialogue box (curtesy of Martin) that will give you her current mass. Divide THAT by 149,001, and save it somewhere. For example, if your mass is currently 145,000 kg, divide 149,001 by 145,000 = 1.027593103. This means that if you fired up your FF Drive now, your initial acceleration would be about 1.0276 km/s/s.... handy to know, since now you know what your Firefly Drive delta-V will be at this point.
But WHEN do you do this? Also very quickly determined with a little knowledge and planning. Two formulas:
d = 1/2 * g * t^2 This is a formula from Newton that says if you know what your "g" is (acceleration), and the amount of time you'll be applying it ("t"), you'll be able to figure out the distance ("d"). Simple algebra will solve for other variables if you know a different two out of the three available in this formula.
v/a = t This is is an algebraic manipulation of the classic "v=a*t", Velocity = Acceleration time Time, another Newton Law
Keep the above in mind - I'll come back to it later.
For now, you're on your way to, say, Mars, and you're booking along at 2500 km/s towards it after a big flash-and-burn from your trusty Super FF Drive. If you bring up your Orbit MFD and set reference to Mars, it'll tell you what your time-to-peripasis is. Next, get your current delta-V (which you can figure out by "149,001 divided by (Current Mass) times 100 (the FF Drive factor at maximum, Ctrl-8). Say you're at 74,500 kg weight after your intial burn to send you on your way; this means that your total possible acceleration is 149,001 divided by 74,500.5 = 2 km/sec at NORMAL FF thrust, but 200 km/sec at your needed (Ctrl-8) 100x FF thrust.
You're barreling away towards Mars at 2515 km/sec (just an example). Divide 2515 by 200 = 12.575 secs to reduce your velocity by -2515 km/sec w.r.t. Mars.
Here's the tricky part: divide 12.575 by 2 = 6.2875 seconds. Add 5 seconds (the time it takes for the FF Drive to spool up) = 11.2875 seconds. Call it 11-1/2 to be safe, or even 12 (~ you'll always have a bit of a safety margin anyway, since your initial delta-V will increase at the FF Drive burns fuel, but these are good approximations ~). THIS is the periapsis time at which point you need to activate your drive.
Why did I divide by 2? See the first formula, and think about what's going on. If I activate the drive at 12.575 + 5 seconds for spooling = 17.575 seconds, I'll stop WAAAAAY short of the target, and will have to waste more fuel to resume the arrival process. It's the Calculus, baby - I didn't make it up. The distance I would have travelled without slowing down would have been 2515 * 17.575 = 44,201 kms. Slowing down only takes 12.575 seconds - and traverses a distance of only 15,813 kms. - leaving a remaining gap wider than David Letterman's front teeth of 28,388 kms. Sure, a more-than-healthy safety margin, but I don't like to fire up the FF Drive 3, 4 or 6 times just to sloppily hone my approach. But these are just suggestions, and meant only to save some propellant that you may need later for planetfall or docking approaches using your mains.
Good luck in your travels, and feel free to comment or report any issues to me at
zephramcochrane@comcast.net Warmly,
ZCochrane (Shawn Beard)
