Oct 09 2020

Operations Summary – Weeks of 9/28 & 10/5/20

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Kerbin II Mission Updates

On-orbit operations continue as Kerbin II continues to “fall forever”, as Wernher von Kerman likes to put it. The week after it was deployed the spacecraft began regular science operations once through several days of initialization and testing. The instruments aboard collect data constantly and store it on the hard drive until no more space remains. At this point data collection is paused and the stored data is beamed back down via various ground stations, not just KSC. We could collect and down-link data at the same time but this would put a strain on the RTG output that would need to be managed by the spacecraft. To keep things simple, the data collection and down-link are being performed separately – for now.

The spacecraft can collect and transmit data twice per day, the rest of the time afterwards is used to run communications tests with our ground stations and telecom companies. The spacecraft can see all our ground stations, even rising 3-4° above the horizon for short periods to talk to DSN North and South. Science operations remains a priority but once we get more in the groove in that respect additional time will be available for surface expeditions to use Kerbin II to stay in touch with their operation centers.

We’re attempting to take a photo from space once per week. While we would like to take more, aiming the spacecraft requires use of the same fuel that powers the engine that will be used to de-orbit the spacecraft for recovery. When we get down to about half our cold gas reserves we will need to end the mission so to keep it up as long as possible we are maneuvering it as little as possible.

Earlier this week the spacecraft suffered a minor software issue that put the flight computer into safe mode. We recovered it without issue and uploaded a fix to prevent the problem from recurring – you can find out more details in this twitter thread from Ops Director Drew Kerman that goes into how we communicate with and manage software aboard the spacecraft.

Overall the mission is doing well and continues as planned, constantly setting new records for space flight!

Progenitor Fails Again, Pivots for Final Mk7-B Mission

Despite taking new measures during ascent based off the analysis report from the second mission, the third Progeny Mk7-B mission that launched earlier this week also ended in an overall failure when we could not recover the second stage engine. Whether the re-entry angle was too shallow or the rocket suffered too much stress on ascent, the break-up during re-entry was worse than the first mission, where we could at least recover the upper-half of the fuel tank with the air brakes attached. Thankfully though at least this time the flight computer did not crash and we got clean telemetry data all the way to splashdown. Because of the launch delay we were also able to use Kerbin II to relay telemetry from our recovery vessel MSV Aldeny once the Mk7-B upper stage fell below the horizon from KSC’s view.

At least some success for the Progenitor program (and by extension the Ascension program and its future Mk3) came last week when the Boostertron II that pushed the first Mk7-B off the pad was re-fired on our static test stand. This was the first time we lit off a solid rocket motor that had been previously flown, which counts for more than the ones throughout this year that have just been fired and re-fired statically as this does not also take into account the loads and stress put on a booster casing while in flight.

Now that we’ve proven that a previously-flown booster can handle being refurbished and static-fired and, with the recent Mk7-B mission, that a booster static-fired multiple times can survive flight, it is time to take the final step and see if a previously-flown booster can again be flown after being refurbished. In order to accomplish this the final Mk7-B mission has been delayed to allow the integration of a refurbished booster that was used and recovered from the second flight back in August. We will also be using the mission delay to configure the spacecraft to carry an actual payload – the future smallsat platform from Luciole Space Systems that will be used for orbital satellites launched by the Mk8 in 2021.

KerBalloon Takes Advantage of Orbital Communications

While general use of the Kerbin II spacecraft for communications from one point on the surface to another has yet to begin, we have been taking advantage of it during our own surface expeditions for testing purposes (and of course this is currently available to anyone for emergency situations). The high-altitude KerBalloon crew recently returned from a mission to the Kongo River basin and we were able to get a release photo beamed to us from them.

The low-altitude crew has taken things a step further and actually worked Kerbin II into their mission planning. Being able to check in regularly and call for help has allowed them to pack lighter and not rely on so much support from airships that would normally transport them to the remote location. Instead they can piggy-back on a regular ocean transport to save money.

Alaba Ejection Confirmed

The recent encounter of Alaba through Mun’s SOI, the 48th on record, has confirmed to astronomers that the upcoming 49th encounter on Oct 15th will be its last. The moonlet, which has been in orbit around Kerbin since at least the start of November 2017, will be ejected back out into orbit around the sun and likely will not encounter Kerbin again for several decades. This will be the longest-studied asteroid and astronomers are reluctantly in the process of wrapping up their observations. On the other hand, now that it’s not there to observe all the time means they can finally put more effort into analyzing all the data that has been collected over the years and we can’t wait to see the papers start hitting the journals.

ATN Database

The latest update for the Asteroid Tracking Network database is available here, containing 5,817 asteroids and 2 updated with new observation data. Here are the 46 asteroids that were discovered this past week.

From the Desk of Drew Kerman

Out of Character Behind the Scenes stuff

Written on 10/8/20

I managed to go back and fill in another previous Desk Notes entry, so check it out.

Obviously nowhere near my planned 2-week lead time, mainly because The Last of Us 2 is awesome and I must play the shit out of it. Been putting it off for far too long considering it was released a few months ago. Despite the lack of lead time I’m still managing to get everything done in time – my main complaint about lack of lead time is the effect it has on the overall storytelling. It’s hard to plan out complex and interwoven events when I can’t really get it all written out and executed upon ahead of time, because inevitability for such things you’re going to want to go back and change some things, you’ll realize some things won’t work like you wanted and will have to adjust, etc. There are a few things I’m saying now about future KSA operations where I’m also like “shit I hope I can actually do that”, which sucks then if I can’t. Also if anything happens IRL that puts me out of commission that also pauses the KSA rather than being able to let it run until I can get back to it.

So yea, not ideal but so it goes…

Kerbin II ops

the “safe mode” event is pretty much exactly what happened – I sent up “disconect” instead of “disconnect” and kOS crashed. I just toggled the power off and on through the PAW to reset the probe core and get it operational again. Then I reset the instructions, fixed the bug in the boot script and uploaded the new boot file just like it is shown in the tweet thread linked above. There’s no actual Safe Mode due to kOS and game limitations (and over-complexity in it actually being needed) but that’s a good analogy to real-world spacecraft.

Also as the videos in the tweet thread showed that is by and large the only way in which I actually operate the spacecraft. There are occasional instances like the one above where I use the PAW but for the most part the craft is controlled via commands because these are then logged and I have a record of everything that I have done with it that I can reference when tweeting about it and fitting it into my overall operations planning. I also annotate the log a bit with some notes added directly to it for additional reference (like actual dates).

So yea every day I run it through its operations, using time warp of course. When I want to take photos, first thing I do when I load up the vessel is I run the roll thrusters for 5s to spin it up and then from that point I do what I need to do to stabilize it for the photo. Because it doesn’t actually need to spin for thermal reasons but it should, I don’t leave it spinning when jumping back to the Tracking Station (and SAS would stop it anyways) so spinning it up at the start still uses the fuel I would have used to spin it up at the end.

Time warping through each day is also done because I have Kerbalism failures enabled and I need to see if anything pops up. On the Kerbin I mission the antenna (the only antenna, eek) actually suffered a partial failure during the mission. So yea, will the Kerbin II probe actually make it to the end of the year without suffering any problems? I don’t know!

Finally, just want to note that run-checking all my kOS code on a “test vehicle” is also based on actual real-world operations. Have you met Optimisim, twin rover to Perseverance?

Mk7-B mission

Right so first big mistake was that I scheduled this mission when I would be away from the computer coaching, because oh yea that’s a thing I do now again since Covid-19 is somewhat under some semblance of control, or at least most people are willing to accept that it is. I didn’t even realize this until like 3 days prior when it was already all planned out and executed for the most part, so changing anything would have been more hassle to deal with than just leaving it as-is.

The only real problem was the hold call at T-8s. Which, by the way, was not inspired by any of the recent failed launch attempts of the Delta Heavy and SpaceX F9 – I just wanted to see how the Ops Tracker would handle it. I like to throw it awkward situations every now and again. Turns out – it works great! Switches to live telemetry then pops back out into static updates and shows the hold timer and then switches to the new launch time – all without having to be reloaded! But on the back-end I need to replace the vessel database with one that contains the ascent telemetry for the actual launch. This I can do from my phone with an FTP client where I delete the database file and rename another one that holds the updated info.

Fortunately my coaching timetable got moved back and I was actually home for the initial launch attempt so I didn’t have to rely on my phone, but unfortunately here the Ops Tracker fell short and while testing I realized it would not switch back into live telemetry for the second attempt without requiring the user to refresh the page. This was slightly disappointing and I didn’t feel like digging through the code to learn why so the tweet prior to launch I just made sure to tell people to refresh. One thing I did like seeing though was that even if the live telemetry didn’t load, the static updates during ascent did continue, so that was a great fall-back at least.

While Kerbin II was active in orbit during this mission, it didn’t really get in the way of anything and I wasn’t planning on using it at all initially – the mission delay was not written to make the launch line up with a comms window to Kerbin II that was actually serendipitous. It also didn’t actually relay any data to KSC in the game – although it was indeed in position to do so. I have the CommNet settings tuned to 0.99 attenuation through the atmosphere so the Mk7-B actually stayed directly connected to KSC the whole mission. That really shouldn’t be a thing though in this case with it being so low and then on the surface so I still used the signal bounce for the story. But then I did almost goof and had it written for telemetry to be received all the way to splashdown before realizing the Mk7-B is relaying to Aldeny which is relaying to Kerbin II to KSC and so it would fall below the horizon from Aldeny’s point of view and cut of comms at that point. I didn’t check to see when this was, I just decided it would be after full chute deploy.

The booster recovery photo includes a small detail not many will probably notice – the inline chute part is actually used, you can see the opening from where the chute was deployed rather than an intact casing. This was easy, just using Vessel Mover to lift up the vessel and then staging the chutes caused them to pop out, then placing the craft back down caused them to cut.

The re-entry photo I originally wanted to have looking downwards, but apparently the re-entry heating effects don’t show up in the HullCam views. I have gotten them to appear for the Ascension Mk1 so I think the Mk7-B is too small and the cameras are clipped into the effects so they can’t be seen. Looking upwards was the only way to see something, likely due to Re-Entry Particle Effects adding such a cool flame tail.

Lastly, the game gave me some science credits for recovering this vessel – why exactly I don’t know because it’s not the first I’ve recovered since installing the latest Kerbalism update with the science overhaul. I still added it as income for the Mk7-B though and attributed it to the work the rocket has done in moving forward on booster re-usability.

Okay yay this is all the work I need to do for tomorrow so now back to playing Last of Us 2