Reentry:1968 NASA Misson Planning and Development Project Apollo

[Levelord]

I saw an interesting re-renty video from 1968 by Nasa and has some interesting bits of information that you Kerbonauts might enjoy!

[Munstation]

That was quite enjoyable and useful, thanks for that.

[RawChicken]

Awesome!

curse you imperial unit system!

Atmospheric reentry is harder than what I imagine! Its awesome they were able to do that back then!

Also, in KSP, right now, atmosphere planet = easy landing, well, once reentry heat is implemented, I guess atmosphere will equal hard (possible mortal) landing while no atmo. planets will be the "easy ones"

Very good video!!

[Paul Kingtiger]

Brilliant find! I've been using Deadly reentry and had worked out a lot of stuff by trial and error. This gives me a much better handle on the situation. Now to install Ferram Aerospace Research so I can play around with generating lift on reentry (will have to make a pod with off center COG).

Does anyone know the Vacuum Pe for Kerbin?

[bbwonder]

Nifty find! thanks for posting

Nice to see how the professionals do it.

It would be cool if KSP modelled the critical angle mechanic.. causing a missed entry or burning up.

Mmmmm toasty kerbals.

[Eric S]

How bad reentry heating in KSP will be will depend entirely on how the devs balance it. I did a Duna mission for the reddit weekly challenge #40, it was the first time I had used Deadly Reentry, and despite the fact that on Duna, I did a straight transfer-to-landing aerobrake maneuver, I never saw any reentry heat. Likewise, on the way back to Kerbin, I did a 36k aerobrake maneuver that took me from tranfer velocity to an 880K apoapsis in a single pass with no heating on the heat shield. After all, we're reentering MUCH slower than the apollo missions did, since Kerbin orbital speeds are a third or less than Earth orbital speeds.

On the other hand, just to make sure that I had installed DR correctly, I reloaded a save just as I entered Kerbin's SoI and tried a 34K aerobrake, and went from "ooh look, finally a heat bar on the heat shield" to BOOM! in 10 seconds flat. I'm hoping that whatever formulas the devs use it isn't that touchy. Basically, there's a very narrow margin between a perfectly safe reentry with no excess heat and almost instant disaster. Realistic, yes, but not sure it's appropriate.

[Eric S]

double post, sorry.

[azazel1024]

Nifty find! thanks for posting

Nice to see how the professionals do it.

It would be cool if KSP modelled the critical angle mechanic.. causing a missed entry or burning up.

Mmmmm toasty kerbals.

Missed entry really just meant bouncing too high and dying from asphixiation as your oxygen ran out waiting for another reentry.

There really wasn't a "skip in to outer space and never coming back" issue with Apollo or any other. The issue is, once seperated from the service module, the command module as a very, very finite amount of breathable air and power. It isn't minutes long, but it is only a couple of hours. You bounce off the atmosphere to a higher orbit and you can't hold your breath for the hour or two it might take for you to reach apogee start descending and hit reentry again, let alone where you will be when you reenter (lets keep in mind all US manned capsules were designed for water spalsh down, NOT solid earth landing).

In either case, too steep or too shallow was fatal. I just don't like the misconception of "skip right off the atmosphere" end sentence. When it should be "skip right off the atmosphere and run out of air and power before we hit it on the way down again"