# TutorialA Newbie's Guide to a 20 step round-trip to the moon.

#### insanity

##### Blastronaut
Donator
I just started playing around with Orbiter and I must say that the learning curve is quite steep and is a fairly intimidating simulation when you think about the vast scope and the ability to explore it freely. I watched the tutorial video of the moon flight and was able to replicate what I saw (after a few tries), but the vast array of MFDs and addons made it quite daunting to take that experience and apply it to efficient spaceflight beyond the moon. Over the last week or so I've decided to learn how to do a return flight with a few different tools and after completing a few successful returns (complete with deadstick landings) I'll offer any fellow noobs some of what I have learned by way of tutorial. I will assume the reader has a basic understanding of concepts like inclination, delta-v, adjusting the altitudes of orbits, relativity, and gravity (if not, there are wonderful resources on the web and understanding these things are essential to understanding the language of Orbiter).

Dan Steph's DGIV- a total workhorse and great learning craft. Also a lot of fun to fly
IMFD- A great tool for planning an efficent journey
Launch MFD- Will calculate launch headings and windows to launch into alignment
Aerobrake MFD- Will assist you in atmospheric reentry by graphically illustrating your landing path.

Step 1: Run the DGIV config program and make sure that you have default fuel and a fair supply of oxygen (I usually prefer a month for the moon)

Step 2:Start any of the DGIV scenarios or edit a scenario using any date/time and location you want (make sure you have the DGIV). When you enter the cockpit load the DGIV settings using the lower panel and then open the canopy to use the Earth's oxygen.

Step 3: Open the Launch MFD and target the moon. The default altitude of 220 will make a fairly efficient takeoff. Wait until time to intersection is around 600sec (T-5 minutes to launch), close the canopy check vessel-state (cone, doors, flight control on atm auto). If you want, the computer will run the takeoff checklist and return any values that need correcting by typing 'd61'. At t-10sec apply thurst to takeoff- either hover or roll- and turn to the launch heading in white at the bottom of Launch MFD. Pitch up to 70 degrees to clear the lower atmosphere.

Step 4: Eventually the launch mfd will display a compass and target on your HUD. Follow the target by keeping your pitch indicator (not velocity-vector cross) lined up with the cross hairs of the launch mfd target on your HUD.

Step 5: Launch MFD will eventually tell you to cut your engines, and when you do open up Orbit MFD, turn prograde, and check that you have acheived an orbit with an ecc value near 0.00 (adjust if necessary by doing a burn at the quickly approaching apopasis).

Step 6: We are trying to make the most of our time, but we want to be precise so open up the Align Planes MFD and double check that you are now roughly in lunar alignment. Make a small burn if relative inclination is greater than 1.

Step 7: Now, for the lunar trip. IMFD will help us get to the moon fairly fast and efficiently so let's use that for our inbound leg to the moon. Open up IMFD and click on MNU to the main menu. You want the course programs so call them up by selecting them with the nxt button and click set when highlighted. We are doing a simple target intercept (no need for ejection burns) so click nxt and hit tgt and type 'moon'. Use the cursor to adjust the GET (4 clicks of nxt) and adjust it to be around 75-80 (because launchmfd was so efficient we can sacrifice the extra delta-v for speed). Click prv and adjust TEJ to find the value that will return the least amount of delta-v for the selected time. Fiddle with GET and TEJ until you get a combination that is fast and fairly efficient (between 3k-5k of delta-v). When you're ready click the PG button and then click BV and finally AB to make the computer find and automatically burn at the burn-vector. Now we are on our way to the moon! Accelerate through time now.

Step 8:Set the Orbit MFD to REF Earth->Moon. Wait until we are in the moon's gravity (.5 or greater) and cut the time-warping. Now we are going to bring up the planet approach feature of IMFD. The easiest way to do this is open a new instance of IMFD on the other MFD display and call up the course-planet approach settings. Make sure the target is set to your vessel (if not click tgt and type x) and that the ref is set to the moon. Adjust your periapsis to 350k click pg, bv, and ab to initiate a burn that will set your perapsis over the surface of the moon.

Step 9: When we get close to periapsis we want to run the circularize orbit function of IMFD so in the main menu click orbital and then ab to drive ecc to 0.000

Step 10: Finally, we want to call up base approach program from the main menu. Set it up for orbit insert targeting Brighton Beach with an altitude of 20k. Watch the map MFD and when you are on the opposite side of the moon from the beach we will burn for alignment. Again pg,bv,ab to set up the burn.

Step 11: Bring up the COM/Nav and tune in 116.3. We won't be doing an entirely VTOL so you can choose which pad you want as we approach the base. When the MAP MFD shows a distance of >500k open up the VOR/VTOL MFD, turn retrograde, and wait for distance to get around 140-160k. Burn retograde to decrease horizontal veloicty to around 50 and then disable the auto pilots and turn towards the base.

Step 12: Find the base and raise your hover-thrust so that the velocity vector falls over the base. Use translation thrust to keep good alignment and rotation thrust to keep good pitch. Keep your horizontal speed less than 100 until we get about 15km out. When we get close, line up the velocity-vector with a pad, close horizontal speed to around 20. Now we are just making fine-adjustments to get right on top of the pad with a horizontal speed >10 and vertical speed >10. Deploy the gear, give it a final slight touch of hover and retro thrust and adjust pitch to 0. Congratulations, we've made it to the moon.

Step 13: Refuel the craft and takeoff using hover thrust at a heading of 90 degrees. When you get some altitude stop hover and start main engines to get an apopasis altitude of 60km. At apopasis burn prograde to make the orbit eccentric and call up TransX MFD.

Step 14: Tell TransX that we are going to be escaping the moon by clicking the + button. Then click VW twice and turn Man. Mode on. Open up TransX in your other MFD and click FWD to see the Earth. In the first MFD click VAR twice and adjust prograde velocity to about 700. Click VAR to adjust the time of ejection and then click ADJ a few times until it reads super. Finally, click + a few times until you have an orbit in the second mfd that will get you back to Earth in a few days (look for the value of MJD of Perapsis) click few on the first MFD to get the target mode and when burn time=0 begin burning keeping the green dot in the middle. When DV is near 0 you can stop, clean it up with translation, and accelerate through time until we get close to earth.

Step 15: I like to take an orbit or two to get everything right for reentry, when I get close to the Earth's influence I usually run the planet approach program of IMFD at a PeA of 350. Again at PeA I run the circularize orbit program.

Step 16: Base approach will make it so on our next pass we can be aligned to land. Wait until you are near the cape to minimize delta-v and then run the base approach program for orbit insert at 350k over the Cape.

Step 17: Watch MAP MFD for when we are on the other side of the world from the Cape (Wait for distance to stop climbing and start falling) turn prograde and call up Aerobrake MFD. Tell Aerobrake to target Cape Canaveral and begin a retro-thurst burn until the grey line is a bit ahead of the yellow line (the distance readout in the bottom should be >60k). Verify that you have a rentry angle that is survivable by typing 'd2'

Step 18: The prediction given by Aerobrake will need to be adjusted when we get in the Earth's atmosphere, but it does give us a good starting point. Run the manual reentry autopilot by typing 'p104s40' to set up descent and click e to run it. When we get below 200k we will polish our reentry angle to get us to reenter about 40k before the base.

Step 19: Getting close! Now we make small pitch corrections using the 4 and 6 keys to keep distance low, but not low enough that we have no room to make any moves that might be necessary. The vessel will start heating up, but just keep making small corrections (up will make us reenter soon and down later- we are effectively stalling the vessel when we aerobrake). Wait for the runway to get insight and the temps to fall off.

Step 20: Runway in sight, but we are probably going to need a bit of a dive to get us there. Hit c twice to cancel the auto pilot, make sure the controls are on elevon and pitch up to stall out and bleed off a bit of speed. Turn towards the runway and start a small dive keeping the velocity-vector on the center line. Gear down at v=200. At about 100 ft, pitch up a small amount and hit b. The speedbrake will cancel out the speed we fell towards the earth and a small flare will put the main gear on the center-line. It takes practice, but it can easily be flown deadstick all the way down.

#### Tommy

##### Well-known member
Not bad. I can offer a couple corrections, but for the most part this is a good tutorial.

In step 3, 600 seconds is ten minutes, not 5. For a DGIV, five minutes is good (300 seconds).

Step 7 can easily cause disaster. "Fiddling" with the TEj here can easily result in IMFD Target Intercept to plot an ejection course that takes you into the atmosphere, or even below the surface of the planet. The source should be set to Earth, not self, and "realtime" changed to "off axis". Otherwise, you settings are OK. The AB in Target Intercept should not be used. Instead, open a second IMFD, and share it with the first. Select Orbit Eject, and change "higher orbit" to "course". Check that the ejection point is correct (dotted green lines aall close together - adjust to minimize DV) and not going through the atmosphere (or worse). Use Orbit Ejects AB to execute the Trans Lunar Insertion burn.

Step 8. Base Approach is a better choice here - the sooner the base alignment is done the cheaper it will be. Set for orbit insert at 100k alt.

Step 10. Since we've already aligned with our base, perform a Retrograde burn on the opposite side of the moon to sower our PeA to 20k ove the base.

These modifications to your plan will increase safety and efficiency.

Also, IMFD's Planet approach can be used for the entire return journey. For an example (annotated fligh recording and PDF) of how to use IMFD's Surface Launch, Orbit Eject, Planet Approach, and Base Approach to perform a return trip see the Home Direct Tutorial. If you'ld rather not re-enter direct, you can set Base Approach to Orbit Insert (rather than reentry) and specify the number of parking orbits you desire (IMFD will take planetary rotation into account so your path crosses the base on the desired orbit).

#### insanity

##### Blastronaut
Donator
Thanks

The 600 secs. was a complete and total error on my part (I'm a political scientist not a mathematician )
The tej fiddle should of been clarified as small adjustments (1x)

I went with the approach-circularize-align-brake method for the moon because it helps build some competency in the different features of IMFD. It is an expensive method.

Also, I usually do the flight home with IMFD because I like having control over multiple varriables, but TransX is actually a hell of a lot easier to plan and you get a nice display with where you can adjust TEJ and Pe. Vel. and see how it effects your HTO orbit and arrival of the Earth. However, I'm going to fix the obvious errors.

#### postal83

##### New member
This is a great tutorial, as I am currently practicing lunar insertion and landing... this simulator really does take lots of practice!!

#### insanity

##### Blastronaut
Donator
I've made a video of a simple earth-moon flight from takeoff to touchdown at brighton beach. I didn't do the best job in the world at flying because FRAPS videos tend to be in the gb range, but I made it to the pad with plenty fuel to spare. If you want it I'll convert into a usable format and put it up on the web.

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