You are not logged in.
It did no go as planned. Something about the computer which runs the launch went bad. Scrubbed.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
Well Boeing was indicating to Nasa that launch was a bad idea due to the leak. So, the outcome of trying did not change the providers stance to not launch.
Offline
Like button can go here
I think that since Boeing has a lot to lose if anything DOES go wrong, this was a prudent decision. But the 2 crew members have a lot more to lose than either NASA or Boeing!
Offline
Like button can go here
We're again waiting for a launch tomorrow; I hope that this time the crew is successfully flown to the ISS.
Offline
Like button can go here
Somewhere among the many news items I looked at was this: there were 3 launch control computers on the ground as part of the facility. One of them had some sort of hardware failure, which slowed it way down. This showed up as a warning on the console in the capsule, prompting the ground crew to chase this down. Turned out not to be a quick fix, so they scrubbed. Sounds to me like they did the right things. Would hate to have a second launch sequencer out of 3 go bad as the fires get lit! -- GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
Finally!! After a series of delays, Starliner was finally sent into orbit by the reliable Atlas V rocket and is on it's way to the ISS. I watched the liftoff on Tim Dodd's Everyday Astronaut channel, which is really a no BS approach.
Last edited by Oldfart1939 (2024-06-05 22:09:50)
Offline
Like button can go here
I saw on the PBS NewsHour site. Looked like a very good flight.
The launch vehicle ascent trajectory appeared to be 153-ish km apogee and 76 km perigee, which puts the Centaur second stage into a spontaneous entry "somewhere"; I never heard anybody say where.
It appears that initially at least Starliner is circularized (or near-circular) near 160 km altitude, with a shorter period than ISS at 400 km. That's how it "catches up". Then it has to go elliptical with apogee at ISS's 400 km, while arriving there in close vicinity to ISS. Then it has to circularize there. Apparently that process takes about a day.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
What to know about Boeing's first spaceflight carrying NASA astronauts
https://phys.org/news/2024-06-boeing-sp … nauts.html
Offline
Like button can go here
Wow! They did it. I didn't think they would. On paper it looks like a very good capsule, but they had far too many delays. Tell me again, how long has SpaceX crew Dragon been operating?
Offline
Like button can go here
News reports I have seen indicate 3 of 8 helium manifold leaking, meaning 3 of the 4 thruster pods are affected. Everything else seems OK except for those helium leaks. They're supposed to dock today.
Odd, people have been handling helium under pressure since long before the Hindenburg disaster in 1937.
GW
Update 11:50 AM CDT: it's just off the ISS, but could not dock, due to some sort of thruster problems with 2 of 28 thrusters on the capsule, according to the report. It's hard to tell, but this sounds like something besides the helium leaks to thruster pods on the service module. The team is trying to figure out what to do before making another attempt to dock about an hour or two from now.
In my own humble opinion, this design is not quite ready to fly, much less carry crew. Thrusters, and rubber seals in helium line flanges, ought to be more reliable than we have seen so far. There are still potentially-fatal flaws in Boeing's design. Different team than the one that screwed up the MCAS in the 737-Max's, but the same corporate management. And corporate sets the company style and culture at all locations. It kinda shows, doesn't it?
Update 12:51 PM CDT: latest thing I saw said Starliner is now successfully docked. That article on CNBC said 5 of 28 thrusters on the capsule were dysfunctional, but they managed to recover 4 with tests while standing off at a safe distance, which recovery afforded enough control to risk docking. Like helium line seals, thrusters are a 6+ decades old technology. Why is Starliner having troubles with these items, when there is so much more that could go wrong? THAT is the question no one seems to have an answer to.
Last edited by GW Johnson (2024-06-06 11:55:14)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
Boeing’s Crew Flight Test on Starliner Docks to Station
https://blogs.nasa.gov/spacestation/202 … o-station/
The Atlas V produces a beautiful launch.
https://x.com/gregscott_photo/status/17 … 0122610028
Offline
Like button can go here
My grades for the hardware: Atlas V; A+ for ULA. Starliner; C+. (Only because they were able to successfully dock and keep the crew alive!); Boeing managed to barely squeak by on this, and their vehicle shouldn't become "man rated," until the issue with the thrusters is addressed.
I personally wouldn't wanna ride in this capsule, but would jump at a ride in Dragon.
Offline
Like button can go here
As long as thrusters have been used, it does make one wonder about the 5 of 28 on the capsule that were "balky". I do not know if these are bipropellant hypergolic, or monopropellant decomposition, but both are many-decades-old technologies. They flew on the X-15, the Scout launch vehicle, and the JF-104 and the NF-104's about 6 decades ago. Not to mention Mercury and Gemini and Apollo.
Monopropellant decomposition with hydrogen peroxide actually dates back 8 decades. That was the pump drive source for the V-2 rocket engine. There's also monopropellant decomposition with hydrazine. Both require only hot catalyst beds to work. The bipropellant designs are all NTO and one of the hydrazines, hypergolic ignition. That's what was on the shuttle, and what usually flies today.
GW
Update 10:24 AM CDT: The wording of the article in the AIAA "Daily Launch" suggested that the problem might have been in the controls, not the thruster hardware. That might most likely be in the software, although damaged wiring cannot yet be ruled out. There ought to be some way to test for this, before the capsule is mounted to the rocket.
Last edited by GW Johnson (2024-06-07 09:27:31)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
From the ‘Daily Launch” for 6-12-2024, following the link to a “Space News” article dated 6-11-2024, a quotation of the entire Space News article”
----
WASHINGTON — NASA confirmed that Boeing’s CST-100 Starliner spacecraft has suffered a fifth, although minor, helium leak in its propulsion system as engineers work to prepare the vehicle for its return to Earth next week.
In a June 10 statement, NASA mentioned that spacecraft teams were examining “what impacts, if any, five small leaks in the service module helium manifolds would have on the remainder of the mission.” That was the first reference to there being five leaks in the spacecraft; NASA had mentioned there were four in a briefing hours after the spacecraft’s June 6 docking with the International Space Station.
In a June 11 statement to SpaceNews, NASA spokesperson Josh Finch said the fifth leak was detected around the time of that post-docking briefing. “The leak is considerably smaller than the others and has been recorded at 1.7 psi [pounds per square inch] per minute,” he said.
NASA was aware of one leak at the time of Starliner’s June 5 launch, having been detected shortly after a scrubbed launch attempt May 6. At the time of launch, NASA and Boeing officials considered that a one-off problem, likely caused by a defect in a seal. However, hours after launch controllers said they had detected two more leaks, one of which was relatively large at 395 psi per minute, said Steve Stich, NASA commercial crew program manager, at the briefing.
A fourth leak was found after docking, although it was much smaller at 7.5 psi per minute. “What we need to do over the next few days is take a look at the leak rate there and figure out what we go do relative to the rest of the mission,” Stich said at the briefing.
NASA closed the helium manifolds in the propulsion system after docking to stop the leaks, although they will have to be opened to use the spacecraft’s thrusters for undocking and deorbit maneuvers. NASA said June 10 that engineers estimate that Starliner has enough helium to support 70 hours of flight operations, while only seven hours is needed for Starliner to return to Earth.
In addition to the helium leaks, engineers are studying one reaction control system (RCS) thruster that shut down during the spacecraft’s flight to the ISS. Four other thrusters were turned off by flight software but later reenabled. An RCS oxidizer isolation valve in Starliner’s service module is also not properly closed.
“We have the commercial crew program, Boeing, ISS teams all integrated, working very well together in order to come up with a forward plan for getting us in the best posture for that undock and reentry,” Dina Contella, NASA ISS deputy program manager, said at a June 11 briefing about a series of upcoming spacewalks at the ISS. “The teams are still working through what are the best ways to go about testing and preparing for undock and reentry.”
Those teams have some time to complete that work. NASA had initially scheduled a June 14 undocking for Starliner, but NASA said June 9 it was delaying the undocking to no earlier than June 18. That delay was to avoid a conflict with a June 13 ISS spacewalk, or EVA, by NASA astronauts Tracy Dyson and Matt Dominick.
“To have it back to back, were we had an EVA followed by undock, was not the most convenient,” Contella said. There are undocking opportunities every few days, governed by the orbital mechanics that set up a landing in the southwestern United States.
The two NASA astronauts who flew Starliner to the ISS, Butch Wilmore and Suni Williams, have been busy both conducting tests of Starliner while at the station while also performing other work, such as science experiments. “Butch and Suni are an extra set of hands,” she said, particularly as other ISS crewmembers prepare for the upcoming spacewalks. “Having Butch and Suni available to perform some key critical science has been outstanding.”
Wilmore and Williams have publicly praised the performance of the spacecraft. “The spacecraft was precise, more so than I would have expected. We could stop on a dime, so to speak,” said Wilmore during a June 10 call with NASA leadership, discussing how the spacecraft maneuvered.
“Our experienced test pilots have been overwhelmingly positive of their flight on Starliner, and we can’t wait to learn more from them and the flight data to continue improving the vehicle,” Mark Nappi, Boeing vice president and commercial crew program manager, said of the astronauts in a June 11 statement.
----
My own take on this:
Given the problems related to decades-old plumbing technologies (helium leaks, RCS oxidizer valve, and RCS thrusters), I see gross inattention to detail by Boeing on this design! As an overall spacecraft, it functions well (“stop on a dime” comment). So also did the 737 MAX function very well. But I see the same sort of inappropriate management culture with Starliner as what killed two planeloads of 737 MAX passengers.
In the case of the airliner, a piece of automated flight control intended as a stall prevention (the MCAS) was fed data from ONLY ONE of two angle-of-attack (AOA) sensors, despite those sensors being well-known to have a high failure rate. How to deal with this MCAS when it seriously misbehaved upon AOA sensor failure was LEFT OUT of the pilot’s operating handbook, along with any mention that there was an MCAS installed at all (in violation of the FAR’s), just to enable a lower-cost overall product (this lack “justified” less pilot transition training). It was precisely the lack of pilot training for how to deal with a misbehaving MCAS that killed the two planeloads of people!
And here is Starliner, flying great (now that the originally-defective flight control software has been fixed), but afflicted with plumbing leaks that absolutely should NOT be happening! It is NOT the same design team within Boeing, but it IS the SAME top management culture! And it glaringly shows!
Why do you think the flight control software was originally defective, causing the public spectacle for the repeat unmanned flight test to ISS? Could that management culture have shorted technical excellence to increase short-term profit or decrease short-term costs?
That is EXACTLY what I think has been causing all the problems that have shown up in all recent Boeing products, meaning things designed since about the mid 1990’s.
And NASA’s management culture has never really been fixed even after losing 2 shuttle crews! If it had been, they would have seen these problems with Starliner coming, BEFORE they cropped up in flight. But, no, they can only RESPOND AFTER THE FACT (which is EXACTLY what the second uncrewed flight test to ISS was, a response to an unforeseen problem). Schedule and money are still trumping flight safety at NASA, as well as at Boeing.
In my opinion, Starliner should NOT be certified “ready” until these plumbing problems and balky thruster problems are fixed. If they don’t do that, then if it flies crewed enough times, the odds will inevitably line up to kill a crew.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
Boeing's Starliner Now Has 5 Leaks While Parked Outside the ISS]
If you’ve been keeping track, there were three leaks on the Starliner spacecraft the last time we checked. Starliner teams had identified two new leaks on the spacecraft after it launched on June 5, in addition to a helium leak that was detected prior to liftoff. The team took some time to assess the issue before launching the capsule, but eventually Boeing and NASA decided to proceed with flying the crew on the leaky Starliner spacecraft without resolving the problem.
The spacecraft consists of a reusable crew capsule and an expendable service module. Helium is used in the spacecraft’s thruster systems to allow the thrusters to fire without being combustible or toxic. “We can handle this particular leak if that leak rate were to grow even up to 100 times,” Steve Stich, manager of NASA’s Commercial Crew Program, said during a news conference before the Starliner launch.
I am wondering how many second guesses are coming now that they ignored Boeing?
While it’s parked outside the ISS, engineers also are evaluating an RCS oxidizer isolation valve in the service module that’snot properly closed, according to NASA’s recent update. An RCS, or Reaction Control System, uses thrusters for attitude control and steering, while the oxidizer isolation valve regulates the flow of oxidizer, which is essential for burning fuel in the thrusters.Mission managers are continuing to work through the return plan, which includes assessments of flight rationale, fault tolerance, and potential operational mitigations for the remainder of the flight,” the space agency wrote.
Starliner is scheduled to undock from the orbital space station no earlier than June 18. The Crewed Flight Test is part of NASA’s Commercial Crew Program and is meant to transport crew and cargo to and from the International Space Station (ISS) under a $4.3 billion contract with the space agency. NASA’s other commercial partner, SpaceX, has so far launched eight crews to the space station.
Offline
Like button can go here
I just today saw a news story that Starliner's visit to ISS has been extended to June 22. Ostensibly, this is for "more testing". However, the spacecraft is docked with its systems turned off and its helium supply valves closed. Turned on, the helium will leak away to zero in only a few days. That much I have seen stated publicly. This is the helium whose pressure drives the propellants to the thrusters. There are no pumps, the thrusters on both modules are utterly-simple pressure-fed hypergolic-ignition designs. NTO and one or another of the hydrazines.
I suspect that they're really still trying to figure out if the service module propulsion will have enough helium left to power the deorbit burn, and if the attitude thrusters on the capsule will be able to hold attitude through entry. If my suspicions are true, you can be sure no one is going to say anything publicly that might verify them. If it turns out they cannot do the job, expect a rescue using crewed Dragon.
GW
edited 6-15-2024 to insert the word "sure" where it was missing in the 2nd sentence of the 2nd paragraph.
Last edited by GW Johnson (2024-06-15 09:12:00)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
Boeing Starliner uses MMH. That's the same fuel as SpaceX Dragon, same as Space Shuttle used for all thrusters on the orbiter, and same as thruster quads on the Apollo Service Module.
Offline
Like button can go here
For RobertDyck re #67
Thanks for the reminder of MMH as a thruster fuel used by Starliner...
I asked Google to refresh my memory, and if found these snippets...
People also ask
What is MMH fuel?
Monomethylhydrazine (mono-methyl hydrazine, MMH) is a highly toxic, volatile hydrazine derivative with the chemical formula CH 6N 2. It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as nitrogen tetroxide ( N 2O 4) and nitric acid ( HNO 3).Monomethylhydrazine - Wikipedia
Wikipedia
https://en.wikipedia.org › wiki › Monomethylhydrazine
Search for: What is MMH fuel?
What is the use of monomethylhydrazine?
What does MMH smell like?
What is the freezing point of MMH?
What is the full form of MMH?
Is MMH a Hypergolic?
FeedbackBoeing's Starliner (CST-100) - Discussion Thread 5
NASASpaceFlight.com -
https://forum.nasaspaceflight.com › ...
Oct 18, 2021 — hydrazine (MMH) and MON-3 nitrogen tetroxide. ... open the thruster bipropellant valves using the same pressurized helium source feeding the ...
Lockheed Martin proposes a mega-lunar lander: 62 tons and ...
Oct 10, 2018
NASA's Artemis Program Updates and Discussion Thread 3
Jan 26, 2020
Boeing's CST-100 capsule updates & discussion
Jun 27, 2012
Hydrazine & Hypergolics - NASA Spaceflight Forum
Aug 17, 2020
More results from forum.nasaspaceflight.comMonomethylhydrazine
Wikipedia
https://en.wikipedia.org › wiki › Monomethylhydrazine
Monomethylhydrazine (mono-methyl hydrazine, MMH) is a highly toxic, volatile hydrazine derivative with the chemical formula CH 6N 2. It is used as a rocket ...
If a NewMars member has the time, I'd be interested in seeing a brief summary of how helium is used in the Boeing Starliner.
Helium appears to be a significant contributor to operation of the vehicle.
A summary might include a list of the fuels used and the purposes for which they are used, as well as the quantities loaded into the system at launch.
(th)
Offline
Like button can go here
Tom:
Thrusters are never turbo-pump-fed rocket engines. They are always very simple pressure-fed devices. They use helium as the pressurant gas to drive propellant flow, because it will not react with the very reactive NTO or any of the hydrazines.
Any of the hydrazines used with NTO are hypergolic ignition, greatly simplifying the design of thruster systems. They are also hypergolic with nitric acid, usually in the form of inhibited red fuming nitric acid (IRFNA), which has a little bit of NTO and a little bit of water in it. However, it is NTO that gives the higher c* for higher Isp, all else equal.
IRFNA and aniline are another hypergolic combination, but again, NTO-hydrazine gives better c*. IRFNA is often said to be hypergolic with other hydrocarbons like kerosene, but that really isn't reliable enough to be "true" for real engineered systems. Maybe wide-cut, but certainly not plain kerosene. It needs to be a light molecular weight hydrocarbon (like aniline), for hypergolic ignition to be fully reliable.
Hydrogen peroxide is hypergolic with kerosene, but only if really high-test: near 100%, which is very very unstable and short-lived. That's what Andy Beal was using. He was the first liquid rocket operation at McGregor. They did have one peroxide decomposition explosion out there, before Beal decided his rocket initiative was not going to make it as a business. His tall firing test tower was SpaceX's first test stand when they moved in after Beal vacated.
Rob:
Thanks, I wasn't sure which hydrazine Starliner was using. Looks like just about everybody is using MMH today. But, it hasn't been that long since Aerozine-50 was still popular. That one is a 50-50 blend of plain hydrazine and UDMH. I'm not sure, but I think some still use it. I think the Russians use something similar to it.
GW
Last edited by GW Johnson (2024-06-15 09:28:32)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
From the “Daily Launch” for Monday 6-17-2024:
SPACEFLIGHT NOW
NASA, Boeing set new undocking, landing date for Starliner spacecraft
NASA and Boeing teams pushed back the target undocking and landing date for the Starliner spacecraft from the International Space Station by four days. They shifted from June 18 to now no earlier than June 22. More testing will be done on both the thrusters on the spacecraft’s aft section. The Starliner crew will also repeat some previously conducted test activities, like the ‘safe haven’ protocol.
With additional data if you follow the link to the article: the 5 problem thrusters on the capsule were physically not performing correctly, and it was the software that shut them down for misbehaving. Testing got 4 working well enough, and they were re-enabled in the software, which is what allowed docking with the ISS at all! As for the helium leaks, there were 5 in all, with the 3rd found being the largest, and by far. The oxidizer valve problem is an isolation valve that refused to close properly, meaning it failed to close all the way.
My take on it:
As old a technology as pressure-fed NTO-hydrazine (of any kind) thrusters are (some 6+ decades), there is simply no excuse for these kinds of thruster misbehavior and thruster plumbing problems in a spacecraft being considered for man-rating! Or even for routine unmanned use! Boeing simply cut too many corners on this design, and it has already bit them quite hard, with the repeat unmanned ISS flight that they had to pay for out-of-pocket.
This is what you get when you are led by “professional” managers at the corporate level who do NOT want to hear anything from their engineers except how much money was saved. And they are not the only outfit afflicted with that flaw. Here’s another one, from the very same newsletter issue:
BREAKING DEFENSE
Space Force boots RTX from MEO missile warning/tracking program
The Space Force has terminated its contract with RTX (formerly Raytheon) for development of the service’s new missile warning/tracking constellation in medium Earth orbit (MEO) due to cost and schedule overruns, as well as technical issues, a spokesperson for Space Systems Command told Breaking Defense.
And this one, still the same issue:
THE NEW YORK TIMES
F.A.A. Investigating How Questionable Titanium Got Into Boeing and Airbus Jets
Some recently manufactured Boeing and Airbus jets have components made from titanium that was sold using fake documentation verifying the material’s authenticity, according to a supplier for the plane makers, raising concerns about the structural integrity of those airliners.
The lesson here: this kind of crap is what you get when you let aerospace defense companies be run by people who only care about the money, to the exclusion of all safety, quality, and reliability. How is this any different from the cheap, crummy crap made by slave labor in China, that floods our commercial markets?
GW
Last edited by GW Johnson (2024-06-17 08:43:01)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
The Starliner will stay docked at ISS not to June 22, but to at least June 26, per today's CBS news website.
Reading between the lines, it seems NASA and Boeing still cannot figure out whether Starliner can bring Butch and Suni home alive. They need more time to convince themselves it can. Which tells me it cannot.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
IMHO, this is a more than dangerous situation; cannot be tolerated by NASA, and no amount of procrastination about the safety of the astronauts can be tolerated. Send SpaceX Dragon on a rescue mission and then see if the Starliner re-enters safely on it's own. NASA is responsible this time, as they were cautioned by Boeing that the problem exists.
NASA is skating on very thin ice!!
Offline
Like button can go here
They're going to ignore the obvious problem, hope their gamble pays off, and if they have any uncommon sense, quietly fix the problem before the next scheduled flight. It's ridiculous, but that's how bureaucratic institutions work. If the gamble pays off, then they look like they know what they're doing, despite not truly learning from rather pointless past mistakes. If not, then we bury another group of our irreplaceable astronauts, there will be another round of pointless bureaucratic regulations that fail to adequately resolve the underlying problem of applying uncommon sense and prudence to flight risk management decisions, and so we will revisit a new form of this same old problem whenever the next crewed vehicle is being developed.
You're expecting a bunch of very smart people to play their respective roles as part of a learning organization. Unfortunately, there's scant historical evidence to support such a belief. They make the same type of mistake over and over again, the fallout from their mistakes produce well-intentioned but silly knee-jerk responses to what could have been entirely avoided with a dash of prudence, and the public disappointment with the follow-on actions (lack of development progress, over-cautiousness in every aspect of the organization's work) will continue. What else could possibly happen? I mean, look, these people are ridiculously high-functioning, which is why they work there or with one of their contractors, but every person has their blind spots, no matter how otherwise intelligent they are.
Where was the over-cautiousness when Starliner's capsule design was submitted for CDR?
Where was the rigorous ground testing of the basic mechanical design and systems control software?
How was it that the testing performed was either rigorous or merely adequate to task when failures continue to show up during flight attempts, before the vehicle ever leaves the ground?
Boeing needs to learn that their paying passengers are not test pilots. NASA needs to learn that one of their flight objectives should include getting there alive. Our astronauts need to have the backbone or intestinal fortitude to tell their managers to get them a known-working ship to fly. I don't care if they're both graduates of test pilot school, or not. Testing to figure out whatever Boeing's engineers could not, was not the overriding objective of their flight to the ISS.
This reminds me of the rudder hydraulic actuator unit failures aboard the original 737 airliners that produced rudder hard-over issues. Our military knew and had known for decades that a rapid descent could cool the hydraulic fluid to the point that valves intended to operate in only one direction would not only lock-up / cease to function, but that shortly after the valve was "unstuck", while the hydraulic fluid was still cold, that a reversal of the fluid flow path could occur in supposedly unidirectional valves. The FAA had the "smoking gun" in their hands after the first 737 crash, but did not recognize it as such, and hadn't brought in outside investigators from the military who had a long history of experience with such reversion of control issues involving crashes of their own jets. After the second 737 crash, someone at the FAA had the bright idea of bringing in some outside expertise in the form of military crash investigators, because the military routinely pushes the limits with their jets. Upon following the testing protocol devised by the military flight accident investigator, sure enough, they knew without any doubt what had caused the crash, and were able to repeat the failure with both new and old / possibly damaged or worn-out rudder actuator hardware. In the end, the crashes weren't caused by actuator damage or maintenance practices. There was an actual design issue that permitted the reversal of hydraulic fluid flow direction in a supposedly non-reversible proportioning valve which caused the crashes. Sadly, many experienced 737 pilots were unaware that such a thing could even happen. On one of the flights, a former military pilot was at the controls, and after their flight's rudder hard-over, he decided to jam the rudder back in the same direction they were trying to reverse out of, which seems very counter-intuitive unless you're aware of what can happen, so the plane and all aboard made it safely to the ground, so the FAA was then able to take an undamaged / in-tact rudder hydraulic actuator from an in-tact 737, back to Parker-Hannafin, and repeat the sequence of events that caused both 737 crashes (steep descent from the frigid cold of high altitude, followed by rudder control inversion at low-speed in warmer air). Boeing was then forced by the FAA to ground the entire global 737 fleet while modifications were made to the actuators and pilot were made aware of what potentially could happen to their flight controls when following similar flight profiles. Airbus has had their share of similar "failures of imagination", but with different components such as software flight control systems.
In that critical moment, most people, even most pilots, dealing with an uncommanded yaw from full rudder deflection are going to try to "hammer down" on the rudder in the opposite direction. Their first thought would not be, "Let's see what happens if I jam the rudder pedal into the direction I never had any intention of going in." On its face, doing that makes no sense. You'd need to understand how such a thing might happen for it to be something you'd try to get out of that sticky situation.
When I was in flight school, the rudder cable in my lowly 172 snapped, thankfully while I was still on the ground, and then the plane jerked sharply to its starboard side during my taxi out to the run-up area, despite my foot being all the way to the floor telling the plane to go to port, to reverse out of the direction I never had any intention of going in. I had dutifully tested the flight controls before brake release, and they seemed fine, if a little stiffer than what I remembered them being in my very short experience up to that point, but they were still free and functioned as expected, until moments later when they simply didn't. Rather than continue fighting with the controls, I immediately slammed on the brakes to avoid hitting other aircraft. My flight instructor was so "ready to go", that he thought I'd made some rookie mistake or wasn't paying attention, so he asked for controls, which I gladly gave to him, and the same thing happened to him. I told him as he took controls, "Something is wrong with this plane. We're not going anywhere." He told me before the flight that I was to act as if I was PIC (check everything on the plane, give the flight briefing to him and to treat him as my paying passenger, etc). He briefly thought he had "fixed" the problem, but as he was struggling with the controls, I turned to him and said again, "We're grounded." He stared straight ahead, thought for a moment, and then turned back to me and said, "You're right. Something is wrong. We're done."
I shut down the engine and my CFI helped me move the plane out of the way by hand. The flight school owner or at least their operations manager came out to see what the commotion was on the tarmac after our exchange with ATC. He looked like he was pissed at either me and/or my CFI for a second, almost like "One of you broke my plane." He asked us which one of us was at the controls, and we explained that both of us had been on the controls at one point troubleshooting the problem, what we had done, etc. One of the mechanics from the shop right across from the flight school removed a cover plate, he looked under the cockpit floor, and said, "The control cable isn't where it's supposed to be. I think it snapped." We were off the hook at that point, and were allowed to return to the school house for our debrief. The following weekend, I asked their duty manager what had happened to the plane, because I didn't see it available to sign out, and he confirmed that the shop told them that the control cable had indeed snapped and they were in the process of getting the parts to replace it from Cessna.
For context, in the Cessna 172, or at least the model we were attempting to fly, a 172RG, the rudder control cable is also connected to nosewheel steering on the ground. The MIA control cable had either bound-up or otherwise caused both nosewheel steering and the rudder to not respond appropriately. That was my first experience, and hopefully my only experience, with a control failure. It's very disconcerting, to say the least. You're in a machine you have to constantly control for it to do what you want, but you no longer have control. It stayed in the back of my mind for quite awhile afterwards, even while flying other planes. The plane in question was "born" only a year after I was. Even if it was perfectly made and designed, everything wears out over time.
What was the underlying point to my anecdote?
Despite what you may think or want "in that moment", you really don't "gotta get there", you "gotta get there alive". NASA still hasn't learned that lesson. Maybe they never will, since they're all "Type A" personalities.
Mercury, Gemini, Apollo, Soyuz (NASA is still a part of operations with that system), Dragon, Orion, and now Starliner. You'd think that the organization operating the vehicles has all the basics exhaustively covered after 60+ years of crewed space flight, with minor variations on the same basic theme. The Space Shuttle was a markedly different vehicle design, but not that different. They're using the same propellants, same basic blunt body vehicle design, and same flight profile. If you have physically stuck valves or malfunctioning electronic control systems, then there should be test procedures for assuring reliability by now. For some strange reason, there isn't. How do we know that there isn't? We have a malfunctioning spacecraft in orbit right now, and we're not real confident that our vehicle will make it back to Earth in one piece.
Something is basically wrong with that. Whatever combination of events and decisions allowed that situation to transpire is what should be corrected, and not by writing-in more explicit rules and regulations that cannot override "gotta get there-itis". Someone needs to step back and ask themselves what they're doing, and why. We have plenty of other working space capsules we can use. Fixating on this one capsule is not worth the risk. There's no up-side to taking that risk. If and when Boeing irons out all the problems with their latest capsule design, Starliner will be a great ride. Until then, it should be treated as a flight test article of unknown quality and capabilities.
Offline
Like button can go here
Nice tale about the 172 with the broken rudder cable. In tail draggers like my 170, the rudder control problem on the ground is even worse. Those want to swap ends while taxiing. Quite insistently, too!
I quite agree with the criticisms of Boeing and especially NASA top management. The only inquest anybody actually learned anything from was Apollo 1. NASA management never learned the lessons from Challenger or Columbia.
One of the problems is time: the people who actually learned something from Apollo 1 were all dead or retired by the time shuttle was flying. There is a built-in human resistance to learning from the mistakes of others, especially when those others are not there in person talking to you. Procedures are supposed to help overcome that, but they're not perfect, even when followed.
GW
Last edited by GW Johnson (2024-06-19 08:36:28)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
Offline
Like button can go here
GW,
I never had any issues before or since that one aborted flight, except a slightly rough-running engine before burning off the deposits. Leaning out while taxiing and run-up always cleared that out, though. My CFI told me the week prior to me showing up, that one of their students had to put his plane down in a field just outside the airport. There are some convenient farm fields just beyond the runway. Almost all the planes at that flight school are late-1970s to early-1980s vintage, though. I think their 182 is relatively new, from the early 2000s, I think. It has a very fancy glass cockpit with Garmin everything (MFDs, nav, comm, the works), and leather seats, too. It's nice. They had or did have a fairly new Skycatcher with a glass cockpit as well, at least when I began instruction there, but they got rid of it for some reason, its engine or lack of support from Cessna or something along those lines. I never flew in that one. I think I had one flight in a 152 with a female flight instructor because my instructor was unavailable. The school had a rule about flying with full tanks, so two males of 180lbs or so would be too heavy for a 152 while remaining within weight and balance, hence almost all flights I made were in 172s. I had two flights in a 172P, when the 172RG was down for said rudder control cable issue, all the rest in their 172RG. I want to say that most flights were about 1.5 hours in length, because the school would only let you book an aircraft for 2 hours at a time, except for cross-country flights during off-hours.
It's funny because they called their 172RG "the beast", but since it was near to the only bird I flew in, that first flight in the 172P felt like we didn't have any power. Shortly after I took off, I asked my instructor why we weren't climbing normally, or normally as I understood it, and if there was something wrong with it. That extra power made a difference. He laughed and told me that the normal fixed gear models were what all the rest of the students did most of their training in, and would only fly the 172RG for the complex aircraft endorsement in their logbooks. Out of habit, I attempted to pull the gear up after taking off, but the lever wasn't there. There was no prop control, either. Everything else was "normal" for a 172.
Anyway, learning to fly was great fun, but then I had to stop after my wife had her first brain tumor. I think I was only able to fly once or twice after that, with all of her medical expenses. Life can put a real damper on the best of plans, but flying was just for funsies, and it was. I would like to go back and get my PPL, but the financial hits from medical expenses kept coming and they didn't stop coming. It was right after the test so that I could fly / train on my own without a CFI present, which was a real bummer. I'll probably have to start over from square one if I ever get to go back, but that shouldn't be too difficult.
As far as Boeing's shenanigans are concerned, they're eventually going to get what they have coming to them, and it will be well-deserved.
The issues at NASA are very disappointing, but I guess when bureaucracy takes over, what was previously a very dynamic learning organization dies an agonizing and drawn-out death. It's still hard to watch, knowing what could have been.
Offline
Like button can go here