mikegarrison

Scott talking about "the semblance of control". Giving the pilots switches to flip so they feel like they have some input into things. This reminds me of the (in)famous temperature control switch on the 707 "Air Force 1" planes. The story is that LBJ kept calling up to the pilots telling them to either turn up or turn down the cabin temperature. So they installed a fake switch on his desk that supposedly controlled the cabin temperature, but actually did nothing. It worked, because LBJ stopping calling the pilots and asking them to change the temperature.

Scott is struggling to think of a scenario where they would have to blow the spacecraft hatch, but apparently he's not thinking of the Apollo 1 fire.

"These suits aren't made for walking" That's just not what they do.

I kinda don't love Tim. He's in the uncanny valley for me.

As opposed to "Air Force"?

Brings up some bad memories. There was this one time I had to go witness an engine noise test. I was on site for three or four weeks, doing *nothing*. This was early '90s -- the first web browser hadn't even been invented yet. We did have one day of good weather -- but it was on a weekend, and the engine supplier did not have weekend overtime budget authorization. It was *so* frustrating. When the test was finally done, it took less than 24 hours from start to finish.

The original "downforce fan car" was the Chaparral 2J. It was not made for Formula 1, but for the Can-Am series. https://en.wikipedia.org/wiki/Chaparral_Cars It was primarily because of Chaparral's innovations that most motorsports series eventually banned moveable aerodynamic surfaces. Cynically, this was because nobody else had engineers good enough to understand what Jim Hall was doing, and they didn't want to have to try to compete with him when he ironed out the bugs in his cars. Later on, there was the https://en.wikipedia.org/wiki/Brabham_BT46#Brabham_BT46B that did run one race in Formula 1.

The tire *does* have to bear the pressure. This is exactly what it is doing by "constraining the volume". The role of the inner tube is to be impermeable and prevent leakages, not to support any "pressure".

I saw it in a paper that had a bunch SARS CoV 2 viruses sequenced. The sequence I copied had a bit in the middle where they just said "129 N", I guess meaning that they hadn't been able to tell for sure on those?

And if I see "N" it means that it might be any of them?

Thanks.

So I've read that it is an RNA virus. I've also read that "T" is not actually in RNA, being replaced by "U". But this is full of "T"s. What's up with this?

So the rocket ignited, but an "anomaly" "terminated" the flight a few seconds later. Obviously they must have had a chase plane.

Can't "rideshare" to a SSO. Or at least, it's very unlikely. That's why they are focused on the SSO market. Typically the buyer is going to want a sat positioned just *exactly* so.

Quoted Pegasus launch price is >$40M. Quoted Virgin Orbit launch price is $12M. (Prices as listed on Wikipedia.) They seem to have similar payload capacities. Their target market appears to be 400kg satellites launched into sun-synchronous orbit.

"Cosmic Girl" is a 747-400 that was previously in service for Virgin Atlantic, so this is far from the first flight! This was the first attempted powered launch. They have previously flown a drop test. (It seems from the twitter feed that they may have unintentionally just flown another drop test.) At first I assumed they launched at the top of that pop-up maneuver, but now I wonder if maybe that was to ensure separation. Maybe they launch just before they pop up. I'm not sure how to find out. OK, so their website says they are "angled skyward at about 27 degrees" during the release, so the release must happen during that pop-up.

12:51 Nearing the launch position Interesting. Just before the launch they sped up, then traded that speed for altitude and popped up 7000 feet in a very steep climb. They must have launched sometime during that. Then they dropped back to FL300 and seem to be headed home. Oops. It appears the launch did not go well after release. They are again flying between the Channel Islands. I guess maybe they aren't supposed to actually overfly the islands because they are a National Park?

12:43 Starting the turn at the north end of the racetrack. 12:45 Turn complete, heading toward launch position.

Their flight plan included a dog leg to avoid flying over some islands (Channel Islands National Park), but they have now diverged from that and appear to be cutting the corner on that dogleg. Climbed to FL300. They flew between the islands instead of around them. They have entered their racetrack pattern. They are at FL300 instead of the planned FL290, but I assume an extra 1000 feet of altitude is, if anything, good.

Well ... flight aware still saying projected 11:40 takeoff, even though it is now 11:56. OK, as I typed that, they changed it to 11:55 scheduled takeoff. "En route". The takeoff may have been delayed by weather. It appears there were some cells near the airport. Their takeoff route was a loop to the north and east, apparently to avoid flying through the weather. They are now at FL275, following the flight path. Now (12:20) crossing the coast and heading out over the water.

Flight was eventually scheduled for 11:40, but no word yet that it has taken off. Flying laps around a "racetrack" is the same thing we do for noise testing, except our racetrack pattern includes simulated landings or takeoffs.

Shuttle launch windows to reach the ISS were anywhere from 2.5 minutes to 10 minutes wide. This depends on how much fuel the vehicle has for trying to change their orbital parameters. None of this "let's wait 30 minutes and see if the winds are better" stuff.

https://flightaware.com/live/flight/N744VG This says 11:50.

They were scheduled to have taken off an hour ago. Do we know if it happened?

I think we seem to be getting away from the original question. It did not seem to be in the context of a telecom sat, but rather a relay to a rover that is far from the Earth. So you would definitely have two different points to aim at -- the rover and the Earth. Probably you have some kind of antenna to point toward the Earth, and likely another antenna that you use to contact the rover. The question was whether they would use two antennas or whether they would use the same antenna but alternately point it between the rover and the Earth. I am fairly confident that they would use two antennas rather than trying to re-acquire both the rover and the Earth over and over. The ill-fated Mars Climate Orbiter was designed to talk to the Earth and also to be a relay for a lander. Here's what Wikipedia says about it: So we see that in this case, there was one antenna designed to talk to the lander, and a separate antenna designed to talk with the Earth.