May 31 2019

Operations Summary – Week of 5/27/19

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Ascension Analyzes Latest Mk1 Flight, Preps for Mk2

This week saw what we hope was the final test flight of the Ascension Mk1. The team is analyzing the data from the mission to determine if it would be safe to send an astronaut up on the next rocket, which is still awaiting delivery of its engine. Overall the mission was a success and achieved all its goals with a well-guided ascent, proper on-orbit RCS control and LES retrofire testing during re-entry. Next month the full analysis will be released with the final determination.

The other big Ascension news to drop this week was the reveal of the Mobile Launch Platform (see it in the gallery above), which will carry the Mk2 out to the launch pad and remain in place for launch. We’ve finally built a rocket that is too large to fit on any of our regular trucks and since they will only be getting bigger from here we needed a better long-term solution. The MLP wasn’t designed specifically for the Ascension Mk2 – its open launch bay in the center can accommodate rockets as large as 3.75m. The current configuration for the Mk2 has the boosters supporting the empty core stage, which will be strutted to the platform as it rolls out to the pad. Once hooked up to the service towers, the engine clamp will be installed to support the core fully fueled. The boosters rest on thick ceramic tiles with explosive bolts holding them down until the moment of launch.

Speaking of the service structure, the launch pad has been closed down this week so the service towers can be reconfigured for the Mk2 and the crew access tower can be raised. It is scheduled to be completed in time for the Progeny Mk7-A launch towards the end of June.

KerBalloon Suffers Crew Injury

While the high-altitude crew awaited a new delivery of balloons this week, the low-altitude crew still had surplus and was able to embark on a mission ~233km to the north via UTV. The area was very mountainous and they were tasked with carrying out a side-mission of placing seismic sensors for field researchers. After releasing the balloon it ascended to its max 16.5km altitude and drifted several kilometers to the south before coming down on the slope of a mountain. During the climb to reach it, one crew member fell several meters before being brought up short by his safety rope and swung into a cliff face. He was medevac’d by airship with non life threatening injuries and is expected to make a full recovery.

Civilian Aircraft Remains Missing Despite Search Efforts

Making headlines this week across KNN coverage was the search & rescue effort to locate a Deuce aircraft that had departed Sheltered Rock bound for Kravass but never arrived. The flight was a pleasure cruise and the plan filed was for some sight-seeing to the north before arriving at KGA so there was quite a lot of ground to cover as opposed to had it been a direct flight. Still, it was all ground, no water, so the wreckage was expected to be located eventually but no sign of the plane has been spotted and rescue efforts were called off today. Many private pilots however remain captivated by the mystery and have declared they will continue looking – this is the first aviation disappearance on record, no airship or aircraft has ever been lost in transit and not found.

ATN Database

The latest update for the Asteroid Tracking Network database is available here, containing 3,622 asteroids and 5 updated with new observation data. Here are the 28 asteroids that were discovered this past week:

From the Desk of Drew Kerman

Out of Character Behind the Scenes stuff

Written on 5/8/19

What about planes

Still don’t know right now what I plan to do with the Genesis program or when I want to introduce turbine technology. It’s hard coming up with missions for the Civvie/Deuce/Dhumla that are worth making the effort to fly since that takes up a decent amount of time. There’s still always the option of regulating them to more “background” operations just like I’m doing with the KerBalloon program but I haven’t yet gotten over the sense of that feeling like too much of a cop-out. We’ll see – ultimately rockets win out over planes so if time becomes an issue as rocket flights increase in complexity I’ll just have no choice. Regardless, there are no available pilots right now with Ted injured and Jeb & Val tied up in astronaut training so I have a break for a while before I need to revisit this issue.

Mk1 launch #6

Had fun designing this using lessons learned from the last flight – working up a better pitch profile and still keeping the landing within comm range. The installation of the relay tower was only thought of as I was planning the mission so thank you lead time for letting me go back a few days and write that in.

The launch delay was mainly me just wanting the rocket to go up at a different time than usual for a different-looking launch photo. I also do like thinking up creative ways to delay launches and I especially liked how I was able to work in their ability to access the capsule as part of an already in place emergency egress plan. Also the need for a battery swap is legit because of how I don’t use rechargeable batteries yet so in the minutes the capsule was on internal power it would have drained too far to last through the whole mission. This also made me realize though that each re-use of the capsule would require a new battery, which is an expense item I’ve been missing. KSA has even less funds now. Also the capsule telemetry issue didn’t just pop up when the terminal count began – one of the prelaunch tweets said no issues were “currently” being worked, to allude to the fact that it was noticed earlier some iffy data was coming from the capsule but ultimately resolved itself as the connection was just loose until it broke completely. In the game the release of the launch towers does significantly shake the rocket if I don’t offset them back a little bit.

Speaking of batteries the remaining EC levels in the telemetry data was completely wrong for some reason – actually it was like that last launch too I just forgot to fix it for this one. Last launch I made up reasonable values for the telemetry data but this one I just threw them out and blamed it on a bad sensor. The real reason is that somehow the non-rechargeable battery on the craft file got corrupted and was no longer behaving properly. I rebuilt the craft and now it works

This launch took me 4 tries thanks to hilariously stupid oversights:

First attempt failed when I forgot to properly define a variable in my kOS code. I use this extension in VSCode for kOS scripts and it underlines variables that are used but not defined – problem is it does this for variables that are defined in other scripts you plan to include, so its pretty useless at the moment and the legit undefined variable was buried under countless other variables that were indeed defined but in another script.

Second attempt failed because I forgot to re-enable HotSpot data to appear in the PAW which meant kOS wasn’t able to log the internal/skin temperature of the capsule and heat shield. This is actually an item on my launch checklist but it’s a bit generic saying to “check PAW show proper data” but I have to remember what data I want the PAW to be showing, so I’ve added that as sub-items to the checklist.

Third attempt failed because I don’t completely re-write my kOS code I modify the scripts from the last flight. So you can imagine my head hitting the desk when everything is finally working fine during ascent and the capsule did an in-flight abort because I had left in the one line of code triggering the LES at 18.5km. D’OH!!!! At this point I wasn’t even mad any more, just resigned to the fate of my stupidity.

Also this flight made me realize I need to start screen-capping the entire mission since I’m actually doing things in space now instead of just letting the payload coast through space on its own. By this I mean I have a utility that takes a screencap every second which I then compile into a video. This ends up being close to what an actual video would render out to in file size, however it is way less disk space used during the actual capture process.

A final note that probably no one noticed but bugs me now that I realize it – I haven’t been adding the KSC link lost/acquired time stamps to the operation logs for when I simulate plasma blackout on re-entry.

Mobile launch platform

Yes this is what I was screaming about back in April. The original idea I had was to use Modular Launch Pads and just attach wheels to them then create a new launch site along the crawlerway in Kerbal Konstructs so I could place it out there and make it look like it is being moved towards the pad. That is still an option on the table for later rockets but I wanted to try to actually build one myself first. I hit upon using the Konstruction platforms pretty much right away and built out the entire thing over about 4 hours. It’s constructed very practically, with big engine housings, a crankshaft to connect the powered rear wheels to the forward wheels, and support beams under the booster pads – since the platform is smaller along its width they go into large counter-weights on the sides. I even like how I was able to find different plates that I could call “ceramic” to place under the boosters to handle the heat on takeoff. Well lore-wise anyway – in the game I still have to disable heat damage in the cheat menu to not completely destroy this thing on launch LOL.

That brings me to the other ~4 hours of testing needed to ensure I could actually load this up in the game with the fully-fueled rocket on it hooked up to the service towers and launch okay. It actually did not explode or kraken-out the first time I loaded it into the game, which was nice. Two main problems quickly made themselves apparent however.

The first issue was how the rocket was attached to the platform in the VAB to become part of the whole vehicle. The platform root part is one of the booster decouplers, so when I merge it with the rocket I can attach it to one of the SRBs. Even though this is a legit decoupler, and even though the root part of the joined vehicles is changed to the capsule, firing off the decoupler doesn’t actually release the rocket for some reason. I’m not sure how it all works internally and I did try to build it both ways – starting with the MLP and attaching the rocket and starting with the rocket and attaching the MLP. In the end I found that I can just Kaboom the decoupler on ignition (it would normally just be destroyed by the heat but I have that disabled in the cheat menu) and I use BAM to make sure it doesn’t make a big visible bang. So I literally have explosive hold down bolts!

The second issue was with the engine clamp, which for some reason if I save it with the craft file then when I load it to the pad it likes to jack up the whole vehicle and cause the platform tracks to no longer rest on the ground. Not only does this visually look bad, when I detach the service towers the whole thing falls slightly but enough to cause the upper-stage engine shroud to suffer a structural failure and fall off. I also had to tweak the height of the platform overall – it was originally much closer down towards the treads and I thought that looked better but what can ya do.

Overall I’m quite satisfied with the construction and am looking forward to being able to use it through several rocket iterations – especially given how fucking expensive it was! It cost a lot more in the game than what I plan to have it cost when I make the entry into the expense sheet but I feel justified in reducing the overall cost because something like this is constructed out of individual parts like a rocket yes but I’m not using most of them in their intended roles, which is how they were priced out originally.