SpaceX Falcon 9 : X-37B OTV-5 : September 7, 2017 : DISCUSSION

[abaddon]

It is a bit confusing. The commentator did say say these were titanium grid fins though they clearly appear to be the aluminum fins.

No, the commentator said that SpaceX is now using titanium grid fins for vehicles currently in production, not that this particular booster was equipped with them. It's a subtle difference but it's there.

"There you saw the grid fins just opened up.  These grid fins are recently moved to being made out of Titanium."  I mean, it's not a big deal (at all), but the commentator clearly misspoke and the statement was that "these" grid fins are Titanium.

[Lar]

I agree with the interpretation that the presenter did say these fins were Titanium.
I agree with the interpretation that they sure looked like the old style aluminum ones so the presenter erred.

I am not sure that a lot of back and forth about this relatively minor point will help us learn much so can we be done?

[zubenelgenubi]

Isn't OTV-6 meant to be launching in 2018 on Atlas V, I am sure there was something about a launch in 2018 when OTV-4 landed earlier this year.

Could be the reason they switched to the Falcon. They got an earlier ride. Just a guess.

The more likely explanation is the quote came from someone that wasn't informed about the change.

Would be interesting to have both OTV's in orbit at once. Guess it would depend if ground support could handle receiving data from both.

Speculation: Concurrent OTV missions would allow 1 flight to handle long-duration experiments and engineering tests, while the other OTV supports the shorter-term or more time-sensitive experiments and tests.

Or, they could fly to different orbital inclinations, again to support different missions.

Or...other possibilities that I haven't thought of!

[Star One]

Isn't OTV-6 meant to be launching in 2018 on Atlas V, I am sure there was something about a launch in 2018 when OTV-4 landed earlier this year.

Could be the reason they switched to the Falcon. They got an earlier ride. Just a guess.

The more likely explanation is the quote came from someone that wasn't informed about the change.

Would be interesting to have both OTV's in orbit at once. Guess it would depend if ground support could handle receiving data from both.

Speculation: Concurrent OTV missions would allow 1 flight to handle long-duration experiments and engineering tests, while the other OTV supports the shorter-term or more time-sensitive experiments and tests.

Or, they could fly to different orbital inclinations, again to support different missions.

Or...other possibilities that I haven't thought of!

Wouldn't having both vehicles in orbit at the same time be an experiment in itself?

By the way would this vehicle going into a high inclination orbit likely to put it over any particular countries?

[kevin-rf]

Or...other possibilities that I haven't thought of!

This flight will not be as long as previous flights and OTV-6 will lift off in 2018 after OTV-5 lands.

Or sometimes tea leaves are just leaves...

[Star One]

Has there been any word on the deployment of the small sub-satellites I believe we were informed this flight was carrying as well?

[Norm38]

Well, if the mission of X-37B is really responsive testing and return of experiments there has to be a point of diminishing returns on mission duration.

Unless duration IS the experiment.  But isn't ISS a better platform for long duration exposure experiments?  Of course, the Air Force doesn't have to share what they're doing on the X-37B.

[Skyrocket]

Has there be any word on the deployment of the small sub-satellites I believe we were informed this flight was carrying as well?

I have heard nothing by now.

[cscott]

Did anybody notice the terminal countdown seems to have switched from a "call and response" format to a "scripted call"? e.g., you used to hear the launch director call "(console designation), verify vehicle in startup" and get a reply "vehicle is in startup". This time you just hear the "vehicle is in startup" call, and it seemed like many of the calls were by the person I'm assuming is the launch director. Comments?

I think there are multiple radio nets, and we usually hear both the call and the response net, but this time we were only hearing one of them. The LD did mention that "second stage callouts are on LDNET" which we presumably couldn't hear on the broadcast because sssh secret.

[Svetoslav]

Almost two hours post-launch, and not official confirmation on whether the launch was successful?

[RonM]

I agree with the interpretation that the presenter did say these fins were Titanium.
I agree with the interpretation that they sure looked like the old style aluminum ones so the presenter erred.

I am not sure that a lot of back and forth about this relatively minor point will help us learn much so can we be done?

Agreed, nothing to learn from these minor errors during the webcast. The presenter is reading from a script, so it's not always going to match up during a live event.

Anyway, it's more important to get the payload in orbit than getting all the details right on a live PR event.

[whitelancer64]

Almost two hours post-launch, and not official confirmation on whether the launch was successful?

"#OTV5 | #AirForce newly launched #X37B space shuttle has separated from #SpaceX Falcon 9 upper stage to begin a long duration mission in LEO"

https://twitter.com/Military_Flight/status/905802037840969730


"#Boeing-built X-37B OTV-5 mission successfully launches for @usairforce @AFSpace on @SpaceX Falcon 9."

https://twitter.com/BoeingDefense/status/905822393280720896

[dnavas]

I'm curious as to how long it takes to stow the returned booster given Irma....
Apparently the Cape is closing tomorrow?

[Scylla]

Does this S1 have the new retractable legs. If so, should reduce time needed to go horizontal.

[Rocket Science]

If we ever get to mod the S2 we could have a fully reusable system with the X-37B!

[whitelancer64]

Does anyone know if the X-37B orbiters have official names or designations? Do they have any distinguishing markings? And do we know for sure which orbiter went up this flight?

[Semmel]

From SpaceX's homepage.

Looks like there are new clamps on the top of the TEL?

They're the same 'yellow strapping' supports seen during rollout. OTV may need extra support, it was originally designed for vertical integration rather than horizontal, so solely cantilevering from the payload adapter may not be healthy for it.

Usually, the payload and the fairing do not have an internal connection. If X-37B requires a support for horizontal integration, it implies that there is also an internal structure, connecting the fairing to  X-37B. Much like the adapter of Ariane 5 where there is a support ring between payloads that connects to the fairing. Seeing a fairing deployment would be interesting for this launch as we would see the internal structure. But of course, we will not see that.

The only internal connection between X-37B and the fairing is the payload adaptor. The X-37B connects to the payload adaptor. The fairing connects to the payload adaptor as well. This was discussed ad-nauseum starting from here: https://forum.nasaspaceflight.com/index.php?topic=37727.msg1646197#msg1646197

I know and I absolutely agree. I know perfectly well how that the payload is held by the fairing alone during integration. Thats the main reason for the limited launch mass of F9 and FH. The dV would in principle allow for heavier birds but the structure of the fairing does not. Thats why all this talk about 50 mT to orbit on FH is bogous unless a new even heavier fairing is considered including an upgraded the payload adapter.

However, there WAS an additional clamp for this launch around the fairing while being horizontal. The speculation by edzieba was that this was required by X37B. If that was the case, then X37B is too heavy to be carried by its butt horizontally. So the load path through the payload adapter wouldnt work for X37B because its structurally too weak, not the payload adapter or the fairing. So if it is structurally too weak, and an additional load path through the fairing to the additional clamps was required there has to be additional internal structure.

I dont think that the fairings stopped being able to support their own weight when held by the payload adapter when before that, they could carry their own weight plus the payload and the adapter for integration. So either the additional clamps are completely useless and superfluous or there is additional internal structure connecting the fairing to the payload. I dont see any other explanation.

[abaddon]

However, there WAS an additional clamp for this launch around the fairing while being horizontal. The speculation by edzieba was that this was required by X37B. If that was the case, then X37B is too heavy to be carried by its butt horizontally.

Maybe there's normally a little "wiggle" in the PLF, and since the X-37B is so wide, they wanted to be extra careful to dampen any movement of the PLF?  I have no idea if that's plausible, but it seems more likely to that the additional clamp was to dampen movement of the PLF, than to support the payload somehow.

[zubenelgenubi]

Does anyone know if the X-37B orbiters have official names or designations? Do they have any distinguishing markings? And do we know for sure which orbiter went up this flight?

I hope Chris G or Ed or JCM or Jim (EDIT or S_G_1962) can chime in...but my understanding, as of the OTV-4 landing, is no.  There are no distinguishing markings, labels, nose art  , etc., to tell the 2 different OTVs apart.

Note the way that Chris G worded his article--the assumption is that OTV-4 was the 2nd flight of the 2nd OTV, and this flight is the 3rd flight of the 1st OTV.
***

There was a different distinguishing characteristic about this launch campaign, noted in Chris G's article--the previous 4 OTV flights were processed at Astrotech Titusville.  This launch campaign used the Boeing facilities in OPF-1.

[zubenelgenubi]

Going back through the update thread postings, I found no mention during the countdown about the space weather conditions.

Was it at all mentioned in the public coverage?