Reentry - An Orbital Simulator - Freedom 7 AAR

So I couldn’t resist this one. Reentry is a spaceship simulator for the Mercury, Gemini and Apollo space flights. Its aim is for full switch fidelity, using the exact procedures they used in the 60’s during those space programs.

@BeachAV8R noticed it on Steam and started the topic - Reentry - new simulator... so thanks to him my wallet gets another quick hit.

As you can see from the welcome message, it’s a one man show and clearly a labor of love, so happy to see some money go to someone with a love for all things spaceflight.

Ok, let’s check out the menu of toys - will there be an accurate count of how many 7/11’s you get in orbit?

An Academy, a Campaign ‘A Bridge to the Moon’ and some missions, both historical and freeplay - and for early access looks pretty good so far:

Let’s get my Freedom 7 Al Shepard hat on, and give this a go:

Ok, let’s dive in completely unburdened by either knowledge or training. Hey, they know my name - I’m qualified!

Let’s light this guy up!

Documentation to read, I love it!

You bring up the mission pad, and then pick a procedure. For the Freedom 7 we’re doing a quick one, so it’s at the 5 mins prelaunch Final Checklist point. The sim can be set to ‘Run’ the checklist (top right in the screenshot below), and then it lights up the buttons for me to press. Perhaps they should have sent a chimp? :monkey_face:

You essentially get a free camera inside the cramped cockpit, and can move around with the cursor keys or the mouse wheel to zoom or free look. It’s sort of like the FSX or X-Plane view controls. You also get a handy (and hideable) ‘view selection’ for jumping between positions quickly (handy in multi-crew capsules I imagine).

Aargh, OK, taking screenshots plus during the countdown is stressful, as no pause button that doesn’t hide the screen (so I can take screenshots). 30 seconds till ignition!

Ok, We’re off!

During key stages of the liftout you hear the actual NASA recordings of the call-outs. I have actually no idea if my oxygen is ok, but it’s probably on here somewhere.

Hmm, it’s looking pretty dark out there. Also, on the way up it’s pretty shaky and vibrating hard so difficult to read the gauges.

The Mercury capsule has a window plus a ‘periscope’ for Earth observations. I bumble my way through the checklists to find out how to open it.

You get all sorts of external and orbital views.

Oh, uh. A test. Apparently I have to try out some manual maneuvers using the RCS system. In theory I would know the controls for those by now. Strangely, bringing up the Settings/Controls page doesn’t actually pause the sim, so I button mash. The Right Stuff indeed!

Ok, Houston, can you repeat the last transmission. Without math this time please.

Houston not so impressed. Activity cancelled!

I have to rush through the retro burn, retro eject checklists, trying to take screenshots on the fly. I fail to to take any on re-entry, so just imagine a lot of fire and orange please. Remember the saying, ‘Aviate, navigate, communicate, screenshots’, in that order.

I really think I missed a step. It’s great the landing bags are out, but a main parachute would be ideal soon. Hmm, which switch?

Mains! Hooray - Freedom 7 lives!

Ok, guys, come pick me up. Do I get a tour of the USS Lake Champlain, as I love my carriers?

So, my school report. Not good. Plus pretty sure that periscope isn’t meant to be out still.

But I lived! The first frog in space - book it!

Ok, so now I’m qualified for the Apollo Command Capsule, right? Hmm, it does seem to have a few more buttons

Now off for some reading. Loving it so far!


Pretty sure that’s engraved on a plaque over a doorway at SimuFlite…yeah…sure…

“…what they’re trying to do to us is send a man up to do a monkey’s work.”

I vote that @fearlessfrog becomes a Twitcher. The Revolution Must Be Broadcast!

Did you start your clock? I thought the only thing to do in space flight was to start the clock. Gotta have that clock running. Maybe two clocks. Clock redundancy. Or just count one Mississippi, two Mississippi…etc…on the frequency.

You need four Butt Kickers strapped to your chair…

Something something periscope catastrophic disaster something something. See…I retained that knowledge!

Seriously though…super cool and looks like a blast. Really love these indie developers with a lot of passion for their projects (see VTOL VR)…


That was literally the only thing I remembered from my training. Sat there in the plasma of reentry I had the ‘oh yeah, should really put that periscope away’. I don’t think I’ll be invited to the Gemini program.

In digging in a bit more, am really impressed. For something like this I don’t care about the lack of VR so far, as I’m hitting the manual at the same time.

The tutorials are decent, plus the cockpits are absolutely fascinating to me, in that I’ve always been a space fan but never tried to ‘work’ one for real like I would with an aircraft. The design of the controls, the computer/sequencer is so interesting - real ‘task based user interface’ stuff. While it was fun to just jump in, I don’t want to give the wrong impression - the training is decent in this one, and step by step as well.

Looking ahead, they have the things like the Athena missions on Gemini, so the ranging radar works, the celestial nav works on Apollo Command Module as well, the computers are fully modeled, aargh, so a lot of depth. Love it.


So are the orbital mechanics there too? Like could you really do on orbit type rendezvous that are physics based?

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Oh yes. I’m getting better on the Mercury side, so will be a while till I get there. :slight_smile:

Unlike Mercury with its fixed sequencer, the Gemini had a mission computer, so a big part of that training is calling up the programs to run for the various orbital maneuvers.


If I see you plot a reentry burn for Pago Pago…I will be… (short hop from Havana to the Cape!)



Ah. My Christmas surprise might be ruined! :wink:


I want Christmas themed parachutes then!

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The Gemini computer is amazing. Unfortunately I don’t think I have enough ummphf for that amount of orbital inclination change for Pago Pago. The service module side of Gemini does do transitional movement, but not as much as Apollo, and I haven’t looked at that yet. Maybe though…

The Gemini computer in all its glory - behold the user interface only a programer could design!

You have to load up a program and then do inputs and outputs direct to memory. So you pick a tape, and wait for 5 minutes for it to load:


You can also spool the program tape manually!

There is also an Incremental Velocity Indicator where the computer can indicate the amount of change in delta V it needs for a target, rendezvous or landing.

It also provides indicators on the Flight Director Indicator for where to point, when it is set to ‘COMP’ mode:

Time to junk that i9 I think, there’s a better option right here:


Oooh, I wonder if I could dock with a Agena Target Vehicle and then remotely control (via the Command Link once hard docked) it to fire its more beefy engine, and if I’m pointing the right way at the apoapsis, maybe?

The command link is where you send three digits (with the last one being either 1 or 0 I guess) as a command using this gizmo:


Hmm, looks like the Agena engine fire isn’t modeled as yet. I thought I might be able to McGyver this one, but not until a patch.




That. Is just scary. They put their lives in the hands of that and the engineers and it is amazing, amazing, amazing that they did they things they did. Insane is what it is. All hail those engineers, programmers, machinists, and astronauts that managed all of that.


What I love so far about this title (I have now gone over the point of no return on worrying about boring people on this one now lol, sorry people) is that the history is so evident from how the cockpits changed in that short period.

You have Mercury with its fixed Sequencer. It had no real on-board digital computer, but it did have an analog computer where you could fix the gyros by manually placing the periscope lines on the orbital horizon - it would do the algorithm in a mechanical way. Sort of slide rule era stuff that works. There was a computer for Mercury, but it was the size of a house, so they radio’d commands up to the Sequencer. Here it is, a sort of fixed step computer:

So it had no ‘programming’ but you could pull one of those rings next to each step. so the astronaut could override the automatic nature of the flight. It goes all the way from launch to landing as you can see (click to expand tall image).

It’s why the ‘clock call’ is so important, in that if the clock wasn’t running then the Sequencer hasn’t started. If it has, then even if ol’ Al Shepard was unconscious right from launch then the systems would do the rest. Fantastic stuff.

Then just a few years forward and you can see how the flights pushed the computer technology. The Gemini spacecraft had an on-board computer. They were so impressed with this they actually called it the OBC (On-board Computer). That as shown above in my other post, it had push buttons to put values in and out of memory direct, with tapes used to load programs and special instruments that could be hooked up to it.

Then comes the Apollo Command Module and its smaller and more powerful computer. Again, so many short years after Gemini and they make huge leaps. It has a digital output! It has parameters you can change on the programs on the fly! It’s like we’re seeing how computers changed just from these three cockpits.

You have verbs and nouns, an uplink command to change the programs.

Did I say I find this amazing yet?

PS Funny thing while playing earlier. I’m using an iPad and the Steam Link app to use this on my PC from the couch while not watching a movie (Mission Impossible LVXII - Why Does Cruise Look Puffy or something) and then realize I’m using a computer to use a computer, while simulating a computer. Yo dog! We’ve come a long way in a short time.


Cool. I’m not sure if the ascent program can be changed, but there is a mission editor. I’ll check how many orbits the Atlas LV allows me to do. I think the O2 limits the amount of time I spend up there on Mercury. Looking it up on wikipedia, it looks like the last Mrecury mission Faith 7 did 22 orbits, so doable perhaps.

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Ah…! So there was more to it than just giving that guy something to do (or make sure of it happening)…



Full simulation of the Gemini and Apollo computers. This makes all my nerdy bits tingly.

Soon as I get home, I’m buying this, installing, and booting up the Apollo 12 launch, just so I can put SCE to AUX. John Aaron has been a bit of a hero of mine for a long time, and he’s a God among electrical engineers.


Apollo is there enough to do up to about Apollo 8, but there’s no manual as yet and you have to use the NASA original docs. Early access style! :slight_smile:

A Lunar Module in this, and the full Apollo 11 is the dream. So far I’m just transitioning to Gemini flights, and it’s a nice way to learn things bit by bit. It’s like the Hornet without a TPOD lol

In the last patch there seems to be Steam Workshop support too, so people are creating/adding missions.

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So uh, I happen to have manuals and documentation for the Apollo Guidance Computer. Wow, never thought it would come in this handy!

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Ha. just looked. There is a new Apollo draft manual. Oh man…

Yeah, you’re going to love it @Navynuke99


I’m at the same level I think. I saw a patch the other day fixed some mission issues I had as well.

I’m done with Mercury, apart from some longer Atlas things I want to try in terms of landings, and have put this on a laptop to get into Gemini when on vacation. Talking of which, getting shouted at for not actually packed as yet, so best get on with it!

See you all in a couple of weeks!