The Apollo 13 Challenge

[Apollo1391]

Well I was thinking that since there are Apollo style challenges I thought it would be cool if someone could recreate the Apollo 13 mission to see if it would be harder to recreate than a Apollo 11 mission. So you will need to disable your service module after you set up a mun encounter and then use your lunar module to guide the crew back home all other Apollo style rules apply. You will also need to take screenshots at launch, in orbit, disabling/decoupling the service module, and re-entering the atmosphere. So good luck and I hope to see how you did I will put up my own pictures soon.

(If this isn't very formal sorry because its my first challenge)

[Johnno]

Xeldrak's "Doing it Apollo Style" challenge sort of includes the main component of what the Apollo 13 challenge would be about, the free return trajectory.

I'm thinking the only addition would be to actually do the entire trip in IVA, after doing your kerbin exit burn (ie free return trajectory burn). Even then, once you've done your free return trajectory burn nothing changes, you could just timewarp until you get to re-entry. I think your challenge is a bit thin on the competition side, you could make up some rules/requirements to make things interesting though.

Free return trajectory itself isn't all that difficult:

Picture for a quick tutorial I've made

From one of my Apollo challenge entries

[Xeldrak]

Well, as Johnno already wrote - if your Trans Münar Injection is done right, so that you are on a free return trajectory, there is no need to guide the spaceship anymore. You could finish your burn, decouple the landing capsule, activate the parachutes and wait. This way you would savely drift around the Mün once and then head back into Kerbin atmosphere.

[Death Engineering]

This is a good idea. I was actually planning on writing up a challenge just like this which includes a save game/persistent file that has a "rigged" CM/LM. Rigged: an action group key that shuts down the CM power and its engine, triggers an explosion and sends the craft into a spin, to be activated after the TMI. Some other rules would be to use the LM "control from here" option and the LM descent engine only. Also, no maneuver nodes allowed after setting off the "problem" action group.

[Death Engineering]

Well, as Johnno already wrote - if your Trans Münar Injection is done right, so that you are on a free return trajectory, there is no need to guide the spaceship anymore. You could finish your burn, decouple the landing capsule, activate the parachutes and wait. This way you would savely drift around the Mün once and then head back into Kerbin atmosphere.

Hahaha good point! There would need to be some other parameters beyond a free-return trajectory to make it a challenge.

[Blue]

No torque allowed by controller bodies-- RCS only

Vessel must be kept in a "Barbecue roll" lest it overheats-- and must be kept so using only the lander RCS

[SRV Ron]

Well, as Johnno already wrote - if your Trans Münar Injection is done right, so that you are on a free return trajectory, there is no need to guide the spaceship anymore. You could finish your burn, decouple the landing capsule, activate the parachutes and wait. This way you would savely drift around the Mün once and then head back into Kerbin atmosphere.

The actual Apollo 13 was headed for a collision course with the Moon so that the third stage would impact in it. Therefore, you would need to be on the same intercept for this challenge to be valid.

At the point of the "Problem, you have an action group that disables the Command Module. This shuts down its engine, SAS, RCS, solar panels, etc... except for the batteries. You then transfer control to the lander but leave it docked to the command module and perform the following maneuvers from the lander;

1. Activate power generation, its RCS system, its main engine, and SAS.

2. Do A short burn on the lander to change course from a collision with Mun to a slingshot that sends you back to Kerban. Keep in mind that everything will perform backwards in relation to the orientation of your command module.

3. After the slingshot, do a course correction to hit a reentry window of about 15,000 meters into the Kerban atmosphere.

4. Just before reaching aerobraking, say 100,000 meters, transfer command to the command capsule, use a second action group to unlock its SAS only, jettisoned the lander, jettisoned the rest of the command module, and aerobrake to a landing.

If you have kept the G forces below 7.5, consider the mission a success. If G forces exceed 8G or you skip out of the atmosphere, then the mission is a failure.

[Xeldrak]

The actual Apollo 13 was headed for a collision course with the Moon so that the third stage would impact in it. Therefore, you would need to be on the same intercept for this challenge to be valid.

No - Apollo 13 was never on an impact trajectory with moon.

It would be madness to steer a manned mission onto such a trajectory even for a single moment, like you never point a loaded gun on another person, even if the safety is engaged. The (allmost) empty S-IVB was decoupled and was then sent on a collison course by ground controllers. You can look this up up at wikipedia.

But it is true, that reallity was more complicated than KSP. Apollo 13 did not use a classic free return trajectory, but a hybrid version wich basically fell short of the mun if you failed to perform a mid-course correction. When their tank burst, this correction had allready been done, and they had to use the LM enigine to get on a return trajectory. You can look this up, too.

Edited August 29, 2013 by Xeldrak

[BlazingAngel665]

I got to eat Dinner with Fred Haise the other day. He was telling us all sorts of cool stuff.

The re-entry blackout was longer then expected because they were coming in too shallow and this extended there reentry time.

2. Jack Swaggert sat on top of the ascent engine during the majority of the trip home (no idea why this came up)

3. They didn't use cabin lights after the flight batteries were deactivated. Flashlights and sunlight were all they had

4. The indicator lights for the valves on the panels were only actually wired to the switches, not the valves, after the explosion this caused some attitude control problems until mission control got it sorted out.

5.He is a really neat guy to eat dinner with if you ever get the chance.

[Xeldrak]

You had DINNER with FRED HAISE? o.O

*envy*

[Apollo1391]

yeah Fred Haise was also supposed to be the commander of Apollo 18, but those pesky budget cuts.