Operations Summary – Weeks of 8/17 & 8/24/20

Progeny Mk7-B Again Sees Partial Mission Success

Yesterday’s second mission launched after a one day delay due to weather conditions. Since we had greatly dampened the guidance fins in order to prevent violent roll-shake during early ascent we had to tighten launch constraints to ensure the rocket could steer properly. Analysis of the first mission led us to believe that a smoother ascent would allow staging sooner after booster engine cutoff so the Mk7-B could keep up its velocity and attain a higher apokee for us to do more work testing the reaction wheels while coasting through space.

During the early ascent this time although roll-shake was indeed lessened the rocket appeared to roll around and have trouble maintaining pitch and heading as if it was unable to properly use one or more of its fins. Although the rocket was not on the proper pitch profile at BECO its velocity, AoA and dynamic pressure were still within limits considered to be safe for second stage flight and the command was sent 3 seconds later by FD Lanalye herself while the rocket was at 19km. However only 3 seconds after that the rocket had lost control and gone into an end-over-end tumble. It flipped upside down, almost all the way around but then airflow forced the large nose back to the rear and it flipped back around right-side up. By then speed and dynamic pressure as well as atmospheric pressure had lowered further to allow the thrust vector control system of the Ospray to hold attitude and regain the pitch profile.

The loss of control during ascent led to an early main engine cutoff similar to last flight, with an additional tumble after MECO further lowering apokee before reaching space. Without being able to get a significant gain in apokee from an engine restart, more attention was instead paid to the reaction wheel system this time around, asking it to point more than just from prograde to retrograde. So while we were able to recover the entire upper stage this time, the mission must still be marked as a failure overall since MES-2 was a primary goal. Now the team will get to work preparing for the next two launches in October.

One or both of those October launches may actually re-fly a booster that was previously used. We’ve gotten confirmation from Periapsis Co. that the refurbished static-fired SRB had a successful burn, so the 3rd Mk7-B could re-fly a static-tested booster. If that goes well, the 4th Mk7-B could re-fly the booster that was recovered earlier this month from the first flight. We also have two fresh boosters set aside to use if needed.

Ascension Prepares for Second Orbital Mission

The power unit for the Kerbin II satellite, the radioisotope thermoelectric generator, completed assembly earlier this month. This means the decay of Kuudite has already begun and the 0.15EC/s of power it outputs will slowly start to decline over time. The RTG was completed on the original schedule to launch this month, and the mission has since been delayed to September. With a 9.2yr half life however this will not present a problem, as when the mission launches the RTG will still be outputting roughly 0.149EC/s. With the Progenitor launch campaign concluded for now, full attention is being brought to the Ascension team working through the final steps of preparing the Mk2 for flight.

Let’s also not forget about the upcoming Mk3 for next year. We’ve released some renders of what it is currently planned to look like. The last aspect that needs final approval are the changes made to the Viklun upper stage, which will be tested on the Mk2 flight next month. If the stage is able to hold attitude properly for a good ascent into orbit then we will have the Mk3 blueprint published in October.

KerBalloon Carry Out High/Low Releases

Crews for the KerBalloon program both had successful missions over the past two weeks. The high-altitude crew took weather measurements in the highlands between Sheltered Rock and Ockr, which is a region that will have a great effect on conditions further to the south where the first surface colony is currently being planned for construction. The low-altitude crew was tasked by field researchers in charge of monitoring pollen levels around KSC to release a balloon with instruments similar to the Atmospheric Fluid Spectro-Variometer over the grasslands just west of the Cape. The aim was to see how well the data could augment the quarterly Civvie flights and already they have a contract for two more releases for the same purpose.

Looking Ahead to Extremis I in 2021

Of all the currently active programs Extremis has certainly been the most obscure, but this is to be expected when the majority of the technology to be used for its missions is still under heavy ongoing development. About the only things we can say for sure are that 1) it will represent all missions sent beyond the orbit of Kerbin and 2) the first interplanetary attempt will be made in late 2021 to send a probe out to fly by Eve, Jool and Plock. This will be a “flagship” mission and carry the designation Extremis I. Missions next year that could attempt to reach Mun and/or Minmus will carry their own planet-specific designations.

The fly by was calculated back in early 2018 and so far no detailed mission planning has been carried out since, again, we are still rushing to develop the technology needed for executing such a complex mission. We’re getting close though, as well as approaching the threshold of being able to fly a rocket powerful enough to get the job done (at least the Ascension Mk3). Without knowing yet our margin for payload, the probe itself lacks a final design as well. Given the very low amount of Δv needed (~2km/s once in orbit) and a travel time of just over 2 years to reach Plock, even if we can only send the smallest of probes the effort would be worth it.

One year remains before we miss our departure window and the Extremis team is now really starting to feel the pressure. Expect that you will be hearing a lot more from them before long.

ATN Database

The latest update for the Asteroid Tracking Network database is available here, containing 5,607 asteroids and 2 updated with new observation data. Here are the 33 asteroids that were discovered this past week.

From the Desk of Drew Kerman