TBH that sounds more like a bureaucratic sabre rattling statement. SpaceX (and Tesla) have gotten similar statements from regulatory agencies in the past. The "it isn't official, until we make it official" regulatory statement.
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I'm not sure what you are saying BO has over SpaceX... Crew Dragon has proven in-flight abort capability and CRS-7 was almost 8 years ago (two months after the first NS flight).
"Simply because they hadn't programmed"? Sure, at 4700 kph at 45 km altitude CRS-7 was theoretically recoverable. However, a Dragon with trunk suddenly alone in the atmosphere is a tad different to plan for than a New Sheppard capsule which started with an abort system and has no second stage nor reconfiguration beyond first stage staging. Not to mention the risk assessment of implementing such a feature (loss of mission) versus the occurrence of it being needed (once to date for F9).
"to go through the landing procedure"
The landing procedure is to have 3,000kg less mass and no trunk before entering the atmosphere heat sheild first. I guess if the attitude had allowed for radio communications, SpaceX could have manually released the trunk (if that was possible) and sequenced the chutes...
"from that mistake"
Mistake? It was not a specified operating mode. No cargo rocket had had such a feature. It's not like NASA had required it and someone screwed up a line of code. It wasn't specified to do that.
"Simply because they hadn't programmed"? Sure, at 4700 kph at 45 km altitude CRS-7 was theoretically recoverable. However, a Dragon with trunk suddenly alone in the atmosphere is a tad different to plan for than a New Sheppard capsule which started with an abort system and has no second stage nor reconfiguration beyond first stage staging. Not to mention the risk assessment of implementing such a feature (loss of mission) versus the occurrence of it being needed (once to date for F9).
"to go through the landing procedure"
The landing procedure is to have 3,000kg less mass and no trunk before entering the atmosphere heat sheild first. I guess if the attitude had allowed for radio communications, SpaceX could have manually released the trunk (if that was possible) and sequenced the chutes...
"from that mistake"
Mistake? It was not a specified operating mode. No cargo rocket had had such a feature. It's not like NASA had required it and someone screwed up a line of code. It wasn't specified to do that.
A reasonable rant. I just wanted to give credit where it was due. We often take shots at BO since they still haven't gotten to orbit yet. In this instance though, they successfully recovered the payload and capsule from a failing booster. Which SpaceX did fail to do when it happened to them. SpaceX learned important lessons from that and, there is no doubt in my mind, they are a better company recovering from their failures. The incredible numbers prove that: As of today, SpaceX's 188th successful orbital launch within the Falcon program in a row and the 107th landing of a Falcon booster in a row since their last failures.
That... is true...
But here's... my issue...
(Did that sound like Shatner?)
Ignoring the difference in mission profiles:
SpaceX lost the cargo from a cargo rated capsule.
Blue recovered the cargo from a human rated capsule.
Both providers have launch systems with full abort capability.
To the booster's defense (in these days of reuse), NS23 was the 9th flight of the N3 booster. It was a technology leader and only intended for cargo missions. The BE-3 engine was the failure point.
I'm glad BO was able to determine what the issues were. Kudos to them. I hope the redesigns are successful... I want to see those suckers fly.
I find it amazing that such root cause analysis is possible with rockets that have blown to smithereens and only the scantest of physical evidence recovered....
I find it amazing that such root cause analysis is possible with rockets that have blown to smithereens and only the scantest of physical evidence recovered....
I believe the article said that BO had upgraded/improved their engine in some way which increased the heat and allowed for the burn through.
They uses term "structural fatigue" that means many cycles of thermal or other stresses? (-> Multiple flights or engine firings) If upgrade was only in this flight, they would said something like "thermal deformation" or "temperature exceeded tolerances". Can any structure or material engineer confirm this?
Note the words “full rate production”. I think the BE-4 web page is simply saying that BO is ramping up engine production to the planned “full rate”, whatever that may be.
Or the web page is just out of date.
Or the web page is just out of date.
Yeah, sounds that way:
"The MIT determined that design changes made to the engine’s boundary layer cooling system accounted for an increase in nozzle heating and explained the hot streaks present."
It's low cycles of operation, but the nozzle experiences high levels of acoustic/ pressure variation/ oscillation in use (especially if throttling), so a single mission could have fatigue vs ordinary overload.
From Wikipedia: "Low-cycle fatigue (loading that typically causes failure in less than 10^4 cycles) is associated with localized plastic behavior in metals; thus, a strain-based parameter should be used for fatigue life prediction in metals. Testing is conducted with constant strain amplitudes typically at 0.01–5 Hz."
Overtemp could lead to plastic deformation.
Look like only one flight. BE-3PM qualified in late March 2022. Only 3 launches occured after that, two crewed on NS4 (first too soon to be it), and one cargo on NS3. Given engineering status, NS23 was likely the first flight.
Yeah, that interpretation occurred to me as well, but that BE-4 page, in the body of the paragraph I pasted, says right after that: "BE-4 is currently undergoing full-scale engine development testing..." which tends to imply they aren't simply moving production towards full-rate, but rather moving towards production.
Also, regarding testing, NASA states:
Qualification tests follow and are conducted on flight-quality hardware at load levels and for durations that usually exceed flight conditions to demonstrate that all structural design requirements have been achieved. Acceptance tests are the final series of tests conducted in a typical hardware program.
So my next question is does one actually launch with engines that have gone through qualification testing? Ostensibly they have exceeded flight conditions.... but not necessarily engine specifications? Table seems to make a distinction between "Flight Quality" and "Flight" hardware,
Bruno says the 2 delivered to ULA are going through Quality Testing, yet he had said they were only going to be shipped after final acceptance testing... implying that acceptance testing happened at BO's facilities... perhaps in conjunction with ULA personnel? Does a customer do both types of testing as well?
Something seems odd about how these are being presented.
Attachments
From other posts on the web (and my vague recollection) :
BO shipped ULA engines that had undergone acceptance testing. In parallel, BO performed qualification testing on separate units. Assuming the QT passed without engine mods, ULA's engines were good to go.
So it seems, that while there may be some overlap, Qualification Testing is a phase that completes prior to Acceptance Testing:
So the pair that shipped to ULA, if they had already undergone acceptance testing, that implies qualifications testing completed prior right?
I guess the question becomes: are Qualification and Acceptance testing done for each article? Or is the design Qualification tested and then individual units are each accptance tested?
Otherwise from your twitter link that the engines ULA had did not undergo qualification testing, and were shipped to ULA to test/accept. Which if the qualification step is only for the program, might make sense...
Right, that's a program timeline, not a per-engine testing regiment.
Normally, the engine family gets qualification tested to validate the design. After that, individual units get acceptance tested to validate manufacturing/ their build out.
In the case of ULA's engines, they accelerated timing by doing acceptance testing and shipping those engines, then they performed the qualification testing. Assuming qual passed, there is no difference from the normal flow. If qual had failed, it would gave invalidated the acceptance testing and the engines would have been reworked and retested.
Ok, thanks.. that validates what I thought must be the case.
Then in which case it moves back to BO's stating that "BE-4 is currently undergoing full-scale engine development " that's the strange statement about the engine status.
While I wouldn't rely on web pages for up to date details, as of Feb 23, BE-4 had NOT finished qualification testing.
So, "BE-4 is currently undergoing full-scale engine development testing at our facilities in Van Horn, Texas." is accurate.
It’s worth noting that BE4 will need to go through two qual campaigns, one for the Vulcan mission and one for the much more rigorous NG mission.
And the first two Vulcan launches are also qualification flights for carrying national security assets.
So it's undergoing development testing, qualification testing, AND acceptance testing, simultaneously?
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