SpaceX Falcon 9 historic landing thread (1st landing attempt & most recent missions)

Rex R said:

nice onboard view of the landing. I did notice that their animation showed them launching from Florida...oops.
Rex

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Did it? I looked and didn't see where that happened. The animation did show the USA turned so you're looking at California on the bottom, with East pointing up, and the Southern trajectory took the rocket to the right of the screen. Is that what you saw?

If they accidentally showed the wrong animation elsewhere in the broadcast then that could explain why I didn't see it. I only started about 5 min til liftoff and turned it off when they went off the air for about 45 min waiting for the second stage to burn again.

As George and Thirstybarbian describe the Merlin 1D uses a turbo pump powered by the same fuel as the main engine. It pressurizes the fuel into the combustion chamber. The exhaust is then dumped out to the side of the nozzle. You can see that in the picture below. In most engine designs that exhaust is fuel rich (to keep things cool I believe) and you can see that it looks like it is burning once it hits the main exhaust plume. As George says the 'base drag' sucks up some of the exhaust plume and you can imagine that a lot of the turbo pump exhaust is fodder for the flames we see above the nozzles.

For comparison, the Russian RD-180 is a staged combustion engine that dumps the exhaust from the turbo pump pre-burner into the main combustion chamber where it can contribute to thrust and thus produce a higher ISP than a gas-generator engine like the 1D. (The latest 1D has the highest ISP for a gas generator engine.) But the trade off for staged combustion is much higher complexity in design and construction.


Tony

Merlin engine on the test stand with turbo pump exhaust visible: (from Nasaspaceflight forum but likely supplied by SpaceX)

Bonus:
Elon posted a sped up video of the landing:
https://www.instagram.com/p/BVxysOlA04j/View attachment 322895

Man, that's a beautiful photo!

This photo of the launch of Mercury-Atlas 2 (MA-2) gives a great example of oxygen rich turbopump exhaust (orange-ish sort of billowing flame) , to the right of the intense bright engine exhausts:



Also, this Saturn-I launch (SA-7, or AS-102), September 1964. A lot of yellow-orange-ish turbopump exhaust visible to the left of the engine exhaust.



As with Falcon and Saturn-V, and others, those used RP-1 (refined kerosene) for fuel.

For the Falcon, the pump exhaust flames are mostly hidden from view during launch inside the clustered engine exhaust plumes. But as it gets moving faster and there is less pressure at the base (base drag), as well as less atmospheric pressure in general, the turbopump exhausts spread out and recirculates.

That is what is visible flickering around the engines. And they have protective base panels in place to protect the insides, just as the Saturns did.

Here's a cone of hot gas recirculating around the fat bottom of my Warlock. Base drag, baby!

Great pic, Thirsty-B


Neat photo of the Iridium launch, climbing out of the fog layer. Do not know how it was shot, but probably aboard a plane far enough away.

Source: ©Sam Sun via @NASASpaceflight

Next launch is scheduled for no earlier than Sunday with possible hold down test on Thursday of this week. If accomplished, this would be three launches is nine days. Yikes!

The critical factor will be whether the launch pad can be inspected and made ready that quickly.

Full article here: Spaceflight Now

Peartree said:

Next launch is scheduled for no earlier than Sunday with possible hold down test on Thursday of this week. If accomplished, this would be three launches is nine days. Yikes!

The critical factor will be whether the launch pad can be inspected and made ready that quickly.

Full article here: Spaceflight Now

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Very cool to have them launching so quickly!

The article says the payload is too heavy to try and land the first stage, but shows a picture of a first stage in the hanger with legs on it, folded up. Obviously not the stage that will be launching. I think most people reading an article on that site would know the difference, as opposed to people reading it on a non-spaceflight website, so I wonder why they used that picture?

The photo caption clearly states:

"File photo of a SpaceX Falcon 9 rocket inside a hangar at Cape Canaveral. Credit: SpaceX"

Mushtang said:

Very cool to have them launching so quickly!

The article says the payload is too heavy to try and land the first stage, but shows a picture of a first stage in the hanger with legs on it, folded up. Obviously not the stage that will be launching. I think most people reading an article on that site would know the difference, as opposed to people reading it on a non-spaceflight website, so I wonder why they used that picture?

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shreadvector said:

The photo caption clearly states:

"File photo of a SpaceX Falcon 9 rocket inside a hangar at Cape Canaveral. Credit: SpaceX"

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Okay. But I still wonder why they used that picture, instead of finding a file photo of one without legs that isn't meant to land?

Mushtang said:

Okay. But I still wonder why they used that picture, instead of finding a file photo of one without legs that isn't meant to land?

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Typical lazy reporter.

Well, I'm surprised they are going for a turnaround to launch from 39A just 9 days after Friday's launch. Record was 13 days (almost 14) at LC-40, last month one was 14 days and some hours at Pad 39A.

Apparently the pad and the TEL that transports the Falcon from the hangar to the pad, are in pretty good shape and do not require much time to be ready for use again (The TEL in particular since it needs to be ready to have the Falcon loaded onto it probably by Wednesday to mount the Falcon onto it. Static Test firing is set for Thursday, 2 days away.

But of course before the Bulgariasat launch, there were some unexplained delays before doing the static firing two days late, which delayed the intended launch date by two days, then a weather delay, and then a payload shroud valve problem that caused a delay to Friday. The latter issues were "stuff happens". It's the unexplained 2 day delays that pushed back the static firing that leave me really wondering about this plan to do a super fast turnaround shaving 4 days off the 14 day record for 39A. So, we'll see.

Of course if they end up not being able to do it that fast and push it by 2 days they'll still set a record. And many people would be happy that it would launch on July 4th. Except for all the employees, personnel, reporters, etc. that would have to work on the 4th.

mpitfield said:

Typical lazy reporter.

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No, Spaceflight Now is a pretty good site for space news.

SpaceX does not exactly let reporters run around inside the hangar and take photos for every vehicle they launch (Indeed, I don't know that they have ever allowed it for any F9 launch). That photo was credited SpaceX. Do you know for a fact that SpaceX has released a hangar photo of the legless Falcon that is about to be flown?

I figure the reporter had no nice pretty close up picture like that of a legless Falcon horizontal, so went with that one (only photos I can recall of recent legless Falcons were pad photos, not KSC hangar photos). It was (to me) intended more as "eye candy" than a technical instructional image, the key thing was the written story which is definitely not a "lazy story"

It was listed as "a Falcon", not the one that is launching. I sure have no problem with it. If I was a reporter with the same limited choice of photos, I'd probably have done the same thing.

Ironically, one of the commenters on that story page wrote this, about that photograph.

Love that photo, are there any larger ones, so i can have it as my screen background

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Any news on full video of the bulgariasat-1 booster landing?

Sent from my LG-D851 using Tapatalk

No video yet. No landing photos either.

Many times, they do not release landing video till after the ASDS returns to port and then they get the GoPros or whatever they are using. And OCISLY is not due to arrive in port till Friday. The booster landed a LONG way out, do not know how far away, but last report is at its current speed it will be Friday.

I ALSO want to see Sunday's Iridium booster landing. Since it seems it reached zero velocity above the deck and had to shut down the engine in mid-air to avoid rising back upwards, falling a short distance onto the deck (Engine minimum throttle is greater than the Falcon mass at that point)

Rolled out to the pad today. Hotfire expected to be on schedule.

60% chance of weather delay forecast for Sunday's launch.

Both ASDS barges and boosters have arrived in port.

JRTI with Iridium booster yesterday at Port of Los Angeles.

A set of Flickr images of arrival at:

https://www.flickr.com/photos/81789298@N05/albums/72157683530374580



And this later....



OCISLY with the Leaning Booster of Bulgariasat, at Port Canaveral this morning. It took days longer because the booster had a "hot re-entry" without any boostback burn, so its ballistic path was a lot farther out. And perhaps due to the lean they may have come back a bit slower (seems it took awhile longer than usual between the landing and having it secure to begin the trip back)




With Roomba / Octograbber holding it on deck.

My apologies if this has been covered before but is that soot all over the rocket, or is the paint singed/burnt?

Exactimator said:

My apologies if this has been covered before but is that soot all over the rocket, or is the paint singed/burnt?

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Soot. Kerosene is a very sooty fuel.

I'd say both. Depends on the area your looking at.

I agree that it's a mix of soot and also of paint charring.

Static fire went well.

Launch window opens Sunday July 2nd, at 7:35 PM EDT. There is only a 40% chance of GO, due to 60% chance of weather constraints - basically late afternoon rain/storms. It is expendable, so the booster will splash into the Atlantic.

The vessel "Go Searcher" has left Port Canaveral to get into position to hopefully bring back a fairing half (had had trouble getting the chute to work 100%, such as lack of steering and/or line tangling). No point in sending the ship out if there wasn't another fairing test on this flight.

An article on NSF about the mission, static fire, and return of the two boosters.

https://www.nasaspaceflight.com/2017/06/spacex-returns-boosters-third-static-fire-test/

Someone on NSF pointed out that one reason why SpaceX was able to get this one out to the pad so fast (static fire 6 days after a launch) MIGHT be that during the weather and technical delays for Bulgariasat, they may have been able to get a lot of work done in preparing the Intelsat booster.

One very obvious area that is soot is the upper section containing the LOX tank. For most of the flight and a bit after landing, the cold contents cause frost to form on the outer skin. After return landing, the tank is pretty much dry, so it warms back up; the frost melts, carrying away the soot. You can definitely tell where this occurs.

Booster at Port Canaveral, used for the Bulgariasat flight last Friday. View of one of the grid fins (old aluminum with ablative coating) showing melt damage, lost parts. This was apparently hottest re-entry ever for a successfully landed booster. The new Titanium fins held up well for the Iridium flight 2 days later, but that was a lot milder re-entry than this.




SpaceX's Flicker site has a few photos from the Iridium landing and return to port:

https://www.flickr.com/photos/spacex/

I guess the aluminum itself is ablative...

Intelsat 35e Launch still GO for tomorrow (Sunday the 2nd), at 7:36 PM EDT. Expendable launch, no booster return.

60% chance of weather delay Sunday, 40% for Monday.

Launch day probability of violating launch weather constraints: 60%
Primary concern(s): Anvil and Cumulus Cloud Rules

Delay day probability of violating launch weather constraints: 40%
Primary concern(s): Anvil and Cumulus Cloud Rules

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Intelsat 35e Presskit download link:
https://forum.nasaspaceflight.com/index.php?action=dlattach;topic=43211.0;attach=1436500;sess=0


Mission patch:



Webcast link:

[video=youtube;ZKmWeATngb4]https://www.youtube.com/watch?v=ZKmWeATngb4[/video]

Photos below of satellite before being loaded. it's huge.....(and heavy).

A tweet by Stephen Clark:
Intelsat 35e weighs 6,761.1 kg (14,905.6 lbs), heaviest GTO payload launched by SpaceX to date

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That is about equal to the heaviest Atlas V payloads.

Launch still on for later today, 7:36 PM EDT. No change in weather forecast.

NSF article: https://www.nasaspaceflight.com/2017/07/spacex-launch-surge-falcon-9-launch-intelsat-35e/

Photo of it at arrival at Pad 39A



And being elevated.

Webcast now streaming...

weather looks good to me... I'd give it a go.

Abort at T-0:09...No joy.

No recycling the switches and trying again today. It appeared to be an automated abort prior to engine start sequence, no info was presented as to the cause. Only that they'll look at the data and decide what the next launch window will be. May or may not be tomorrow, depending on what they find. Personally, I think someone has to run out to the pad and install a new ignitor...

...aaaaand scrubbed for today.

See ya'll tomorrow at 1937hrs!