That is indeed normal for Delta 4 and its heavy variant, but unique in that no other rocket roasts itself like a wiener dog in that way.
Is it from raw liquid hydrogen dumping on the igniters?
The RS-68A engine gets ‘conditioned’ by LH2 prior to ignition. There are igniters to burn off the residual H2, but maybe they over did it a tad for this launch and turned the booster into a Baked Alaska.
The scary thought is there were serious plans to man-rate the DeltaIV. John Young would have blinked at the thought of climbing onto a rocket who’s first step for liftoff is ‘light the boattail on fire’.
could you explain that further. What do you mean the engine gets “conditioned” by liquid hydrogen?
I also don’t understand how a flare up would scorch the paint like it did unless they paint the boosters with rocket fuel like the Hindenburg was.
The LH2 is used to chill down the turbo pumps and assorted plumbing so they don’t get shocked by the -423 degree fuel. It is a common thing, if you listen to the callouts on a SpaceX launch, you can hear when the upper stage Merlin engine gets chilled midway in the first stage flight.
The reason for the rocket flambe is Hydrogen is lighter than air–it dumps out of the bottom of the rocket, rises up and gets ignited when the engine lights off. The Space Shuttle did the same thing, if you see any footage of the engines lighting, you can see sparkler like things–they were for excess Hydrogen, not to start the engines.
If you want to read a real horror story, google SLC-6 out in Vandenberg that the Shuttle was supposed to fly from. Not only were there a problem with the construction workers passing their pee tests, but they discovered that the exhaust ducts would trap and concentrate the Hydrogen gas to the explosive concentration…
Ah, I always thought the sparklers WERE the engine igniters. Good to learn. I’ll have to check out the Shuttle story.
This video explains it pretty well:
Basically it seems they flood the flame trench with H2 prior to ignition in order to displace any and all O2 nearby in order to stabilize the engine combustion startup (in addition to the required pre-chilling of engines which is totally a legit need). However, the decision to displace O2 in this way is an extremely poor design decision in my opinion and could be better replaced with an inert gas. This among many others bad decisions basically mean that Delta 4 will never be man-rated and is a technological dead-end.
Was a real pretty launch and rocket return as viewed from the new palapa at the beach at Minutemen Causeway. And boom, boom… upon landing.
Is it true Elon Musk said, “Vee just shoot zem up who cares where zay come down…”
“That’s not my department”, sayd Elon von Musk.
The Falcon Heavy static fire took place this morning. Elon tweeted out that the launch would be in a week or so.
Pretty neat. Some third-party videos:
SpaceX - Falcon Heavy Static Fire 2018.01.24 - YouTube“Didn’t explode, so that’s good, right?”
If you listen carefully, you can hear a kind of drumbeat sound from 0:21 to 0:23 in the first video. That’s the engines cycling up sequentially: they turn on pairs of engines 200 milliseconds apart so as to put less strain on the airframe and other components. It’s too much of a shock to turn on all 27 engines at exactly the same time.
Falcon 9 scheduled for Tuesday, 1/30…Very windy yesterday afternoon out at the beach. So a 2nd stage sensor replacement and high winds yesterday cause scrub. Today’s forecast shows weather at 90% chance of launch. No 1st stage returning to the landing zone nor the barge this time. Just a plain old fashion rocket launch. Have read 3 different reasons Spacex isn’t trying to recover the 1st stage today… 1. Not enough fuel for either the LZ, land landing or the barge landing due to this payload going much higher since it’s doing a geosynchronous orbit. #2 The 1st stage is old (May of '17) previous launch and not worth recovering. #3. Can’t land at the landing zone, LZ1 because it’s being readied for the dual landings next week of both Falcon Heavy 1st stages.
I choose #1 as the reason.
It’s 2–The Block 3 first stages are being splashed because they have Block 4’s now, and Block 5’s Real Soon Now.
So this Falcon 9, 1st stage will …sleep with the fishes in about an hour. Fine. As long as it doesn’t veer west and crash onto my cool, 29" silver, all aluminum beach cruiser.
That I could not forgive.
Launch successful. They’re getting as good with the reused boosters as they are with landings.
It does seem that the descent wasn’t totally uncontrolled–they had a reentry/landing burn and leg deployment before splashdown. Unclear whether it could have landed had a barge been there, but it couldn’t have been too far off.
So I say a combo of 2+3. They probably could have made the extra effort, rushing the barge back to port before being readied for the Heavy launch, but being a Block 3 core it wasn’t worth it.
It seems they tried a 3 engine landing burn . The last time they did that, welding was required for the barge deck, so maybe they took a chance and pushed the envelope a little–not that they want anything to muck up the barge ahead of next week’s fun!
Ha ha–the rocket actually survived!
I mean, they aren’t actually going to reuse it or anything, since immersing sophisticated aerospace hardware in salt water is about the worst thing you could possibly do to it, but it’s pretty amazing that the structure is more or less intact.
Ironically, this actually is a pretty serious failure–normally, the stage would largely sink to the ocean floor, being broken into dense chunks, and any remaining buoyant pieces would be small enough to not endanger shipping traffic. But an intact stage is kind of a serious hazard to ships, so they really need to recover it at this point.
So what’s the motivation for a 3-engine landing? I thought even one engine had too much thrust for a gentle landing.