May 05 2017

Operations Summary – Week of 5/1/17

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Progeny Mk3 Final Flight Report

We have analyzed the data from the last launch and have found it to be satisfactory overall but have learned that the Mk3 had the potential to get even higher, if not by much. The ascent for the final launch called for the flight controller to initiate booster ignition during coast once the pitch of the rocket had decreased by 2° since the previous booster had been decoupled. Launch occurred at a pitch of 85° and the initial acceleration of the rocket pushed the nose up to 86° before the spin was initiated and pitch stabilized back towards 85°. The coast period of the second stage was defined by the gradual decrease in pitch from 85° to 83° over the following 22 seconds. After the second stage was dropped, the third stage began its coast from 82° – but it never reached 80° and the booster was ignited when the backup parameter was met as the vertical speed dropped to 0. This led to a momentary flattening out of the trajectory that ultimately cost us at least several hundred meters in altitude.

The purple line is altitude. Note how flat the trajectory becomes before the final boost. Click the image for the full telemetry data

The Progenitor engineers agree we are getting closer to an optimal ascent profile but much more tweaking and experimenting needs to be done. For the Mk4 we have several changes in mind. First, we are going to be playing around with the amount of thrust produced by the first and second stage boosters, as currently they push the rocket’s dynamic pressure values far higher than is nominal. Even though we know the rocket will hold together after the punishing 190kPa endured by the first Mk3 launch, the amount of drag produced is excessive. This final launch saw a Max Q of 96.8kPa during the first stage boost and 51.9kPa during the second stage boost.  We would like to keep dynamic pressure below 40kPa during both segments of the flight (third stage boost topped only 5.6kPa due to the thinner atmosphere, and we can throttle our LF/O engine so only the first two stages are an issue here as far as dynamic pressure is concerned). We will still be launching the first Mk4 with a hot stage ascent to get a baseline for performance, but after that these considerations will be put into effect.

Furthermore we plan to tweak the fin angles once again, since the spin-rate of the last launch was still a bit too fast, and extra spin just uses up energy the rocket needs to climb higher. We feel the first stage fins are good, but the second and third stage’s pitch angles need to be lessened some more due to their longer flight time. We will be dialing them back to make the second stage 0.75° and the third stage 0.50°. Additionally, there was still a little loss of altitude gain in the second stage coast period so we will reduce the coast until the rocket pitches over only 1.5° instead of 2°.

Finally, we will be changing the backup ignition parameter to ignite the booster if vertical speed falls below 100m/s while pitch delta remains below 1.5° – we expect this to only be an issue with the third stage and 100m/s is just a starting estimation based on the simulated performance of the LF/O engine.

Here is a look at all 4 launch trajectories together:

Now that the Mk3 has reached its goal of breaching the upper atmosphere (18km), work has shifted fully over to the Mk4, which we hope will be able to reach space at last. This last launch, when the rocket fell below 100m/s in the third stage coast it was already at 15.7km. With the tweaks we plan to make outlined above we expect to ignite the LF/O engine just within the limits of the upper atmosphere, which means a large portion of the thick atmosphere will be behind it. However if the Mk4 fails to reach space we have two alternate options to explore – 1) strap 3 Mk1-A boosters to the first stage booster and 2) add a second tank to the third stage for the LF/O engine. If needed, we’ll cover the pros/cons of both.

The Mk4 rocket for the first launch is already almost fully assembled from parts that were delivered last month, we await only the delivery of the first LF/O engines in order to set a launch date, which we expect to hear news on next week.

Genesis & KerBalloon Go for 2nd Joint Mission

After the success of their first collaboration last month the two programs are teaming up again to deploy another high-altitude balloon over the same region as last time, only 17km further north. The mission is set to depart on Monday. If all goes well, a third mission is already planned for later in the month, which will take things even further inland, 31km further north. Captain Jebediah will be back at KSC this weekend to fly this mission while Commander Valentina heads up to Kravass City to take her turn instructing the new Civvie flight trainers for two weeks.

ATN Database Update

The weekly update for the Asteroid Tracking Network database was posted here. It contains now a total count of 515 asteroids. No new alerts.

April Finances Posted

For almost the entirety of last month it seemed we would be looking at another deficit in our net income, but with the success of the Progeny Mk3 and several new contracts at the end of the month we have closed the books on April fully in the green. You can review all financial details here.

Celestial Snapshot of the Week

We had our first transit of Minmus this year, and it was a near-miss with the moon only partially moving across the sun’s disk, although from this photo it seems to be fully on it. You can see a composite of the transit here with the Moho and Eve transits shown as well. This year will set a record for transits, with a total of 5. Two more transits are expected later this year, a second Minmus transit on June 29th and a second Moho transit on October 15th.

From the Desk of Drew Kerman

Out of Character Behind the Scenes stuff

Written on 4/19/17

Suffered a bad bout of writer’s block so despite the 5-day KSA vacay I’m still not caught up on things to have my 3-week lead time back, but I’m still able to work on getting caught up. Nothing yet has caused me to stop moving forward and work on things that have to be done – for example the Civvie instrument panel remodel is due to debut with the first delivery of the new aircraft from the C7 factory in Kravass but until that day comes for me to write I don’t have to sit down and work on the IVA instrument placing – hopefully I will be back to 3-weeks lead before then so I don’t have to risk falling further behind. I’m at 2.5 weeks currently. I guess I should also admit that “writer’s block” is just a general term for loss of motivation – although even in times like these my mind is still thinking ahead to things in the future, eventually I work back up to wanting to work to get to those points I’m plotting out in my head. Fuck yes I want to go to space already! 😛

More v1.2.2 Woes

Still struggling to ensure everything is running smoothly on v1.2.2. This week I was forced to admit that stock Asteroid-Redirect Mission asteroids were no longer being generated in the game and I had to take the time to investigate why. Turns out something changed in either Kopernicus or the stock game itself that has affected Kopernicus, but originally I had my own asteroid spawn config setup to only check for the possibility of a new asteroid 60 times a day and now the game, using the same config values, seems to check far, far less. I had to lower the value a lot to get asteroids to finally show up. It was made more complicated by Custom Asteroids, which I thought was outright suppressing the stock spawner but the real reason was a bit trickier – since it would take so long for the stock asteroids to show up, Custom Asteroids would have already spawned enough unknown objects to exceed the maximum amount allowed by the stock spawner. I thought it was using its own internal count of asteroids spawned, not the number of untracked objects. Just another example of a few hours lost to getting v1.2.2 playing nicely.

Cross-post to the KSP Forum

I finally found a good reason to revive the KSP forum thread for the KSA, which is to repost these weekly sitreps much like I cross-post them to Reddit (or the galleries at least). Originally I wanted to use the embedded tweets feature (paste a tweet link – done) of the forum to compose mission reports, but that would have been a lot of tweets and the thread would have been hell to scroll through. In the previous KSA iteration I stuck them in spoiler tags, but those were images of tweets, and the embedded tweets don’t work in spoiler boxes. No way am I taking the time again to make images of every tweet to post, especially when my current mission report format here on the site (which also used to use those same tweet images) looks so damn nice with an embedded timeline. So it just languished for a while until the fix to the imgur album embeds gave me the idea to redo it this past weekend to hold all the operation summaries and will continue to update there weekly. Should help bring about a bit more exposure.

Also in the process I realized I had failed to retconn any Jool images that were featured as celestial images of the week in previous ops summaries, as well as in imgur albums where Jool was used as the cover image. Fixed!

Complex Finances

Keeping track of the funds that flow through the KSA’s coffers has gotten a bit more complicated now that Genesis and KerBalloon are doing joint missions, which means they should each share in the profits of the contracts that are fulfilled in the process. I didn’t want to have to go into deciding exactly how much each program should get given their level of involvement and the amount of funds they have to expend relative to each other and just made it an even 50/50 split. But then Genesis also has a 50/50 profit/expense split agreement with C7, which is a completely separate company that I don’t keep records for. So if a joint contract payout is 6,356 funds, that would mean that KerBalloon would get 3,178 while Genesis would only get 1,589 after their split with C7. However since C7 profits do not factor into KSA profits when I make the income entry for the monthly financial sheet (not the program/craft financial sheet) I have to record the total income as being only 4,767, which is less the 1,589 that was paid to C7 and thus shouldn’t end up in KSA’s accounts. What’s that you say? It’s not so complicated at all? Great! You’re hired as my new accountant.

Also I realized this past week I had forgotten to include the astronaut’s salary payments in the expense columns for the past three months. Whoops!

I also added two additional sheets to my finances workbook that let me better see at a glance what all the craft and crew are currently doing, when they’re doing it until, and what if anything is planned for them to do afterwards. Same data as in my text file with the outline of events to complete but just more condensed and easier to look over to ensure I don’t continue to mistakenly reference astronauts doing some event when they are actually someplace else. Aircraft now also have fields for tracking flight hours and distance, since I will have more than one of each.

150+ Mods Remain

So yea, I just did a quick count and there are still over 150 mods, the majority of them part packs, that I still have to install and check out under v1.2.2. This is only something I can do in whatever spare time I have (which is none at the moment) until it comes to the point where I need to build something completely new and want all the parts possible to choose from – which thankfully is still a few months off. But still. 150+ mods. Yikes. Thankfully the upcoming v1.3 release of KSP means most mods are in feature lock and I’m not spending a lot of time keeping a ton of my mods up to date, which is kind of the reason I tend to remain a version behind stock for the most part.