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Submission + - Boeing 787 had experienced previous fuel cutoff switch failures (financialexpress.com)

Submitted by wired_parrot
wired_parrot writes: While the preliminary report into Air India Flight 171has led into focus the fuel cutoff switches being activated, the exact cause of the activation is still unknown. However, a former inspector general of the US DOT points out that this is not the first time the fuel cutoff switches have transitioned from Run to Cutoff on their own. It happened 5 years ago too: "There was an ANA flight in 2019 in which the 787 aircraft did this itself, while the flight was on final approach. No pilot input cutting off the fuel whatsoever". Because the engine shutoff happened while it was on the ground, the consequences were minor. But the investigation then revealed that it was a glitch in the Boeing 787 software that led to the transition in the fuel switch. The investigation revealed the plane software made the 787 think it was on the ground and the Thrust Control Malfunction Accommodation System cut the fuel to the engines. The pilots never touched the fuel cutoff.
In the Air India flight 171 case, the fuel cutoff also happened to occur during a flight phase transition (from on-ground to in-air). Could the software have misunderstood the situation leading to a similar situation?

Comment Re: Tier 2 time. (Score 1) 242

The Throttle Control Module (TCM) does have separate logic for different flight phases, including on-ground or on-air. Not trying to blame Boeing, I still think its a pilot error issue but that the cutoff switches may have been triggered by the pilot well before takeoff but the cutoff logic may have been inhibited while on ground.

Comment Re: Tier 2 time. (Score 1) 242

The flight data recorder would not have captured the state of the cutoff switch, it will only capture the engine cutoff signal being sent to the engine. One possibility I can think of is that switches were set on ground during takeoff roll, but while the aircraft's wheels were on ground, ground logic would apply. On ground logic would only enable fuel cutoff if throttle was also at idle. Once the wheels were off the ground, the throttle management switches to in-flight logic and throttle idle condition no longer applies - engine cutoff signal is now sent. This would also explain why the RAM air turbine deployed immediately after takeoff. Doesnt explain why it the switches were set to cutoff but it could have happened well before takeoff.

Submission + - Bitcoin price being manipulated by small group of whales (yahoo.com)

Submitted by wired_parrot
wired_parrot writes: In 2017, John Griffin, a professor of finance at the University of Texas at Austin, noticed something peculiar. The amount of Tether tokens, which were supposed to be tied to the dollar, were getting printed in large batches tied to jumps in the price of Bitcoin. In a paper published in 2018, he laid out the case how a single whale was manipulating the price of bitcoin for profit, using Tether.

Although the unknown entities manipulating the price of Bitcoin have never been identified, dr. Griffin now sees evidence that the same malicious actors are now propping up bitcoin. Despite the crypto crash and myriad other negative forces, every time Bitcoin briefly breached the $16,000 floor, it bounced above that level and kept stubbornly trading between $16,000 and $17,000. Almost unbelievably, as the crypto market has continued to unravel into 2023, Bitcoin has gone in the opposite direction, trading up 35% since Jan. 7 to $23,000. The suspicion is that a small clubby group of crypto-investors are coordinating to establish a floor price for bitcoin.

Comment Re:Wow (Score 1) 157

Early aircraft had multiple crew. Asides from a pilot/co-pilot position, they also had a navigator, radio-operator, mechanics (servicing the engines in-flight and carrying spare parts due to low reliability), and flight engineers. One by one each of these positions has been made obsolete due to improvements in automation and aircraft reliability. The aircraft safety record has only improved over time, so eliminating aircrew has not affected safety. One man commercial flight operation is already allowed for small aircraft with under 20 passengers and has not been seen to adversely affect safety. For short haul flights, a 2nd pilot is only needed as a backup, and modern auto-flight systems are reliable enough to handle the small chance of a pilot incapacitated mid-flight.

Comment Not worth it to replace for older systems (Score 2) 85

The problem is that many of these remaining uses are in older out-of-production safety critical systems with regulatory oversight. As an example the Boeing 747-400 still uses a 3.5" disk to update its navigation data which needs to be done once a month. It's a tried and tested system that works. Updating this would require a safety engineering assessment, complete regulatory review to ensure the new system complies, and update the training for the maintenance teams who load in the avionics data in a monthly basis. All this for an aircraft that is no longer being manufactured and is slowly being phased out. It is not cost effective, and I suspect most of the remaining uses of the floppy disk would run into similar issues.

Submission + - FAA shifts gear on certifying eVTOLS, as concern grows (avweb.com)

Submitted by wired_parrot
wired_parrot writes: As a range of new manufactures are preparing to bring to market new mass air mobility vehicles in the form of eVTOLs, concerns growing about the safe certification of these new aircraft types has led the FAA to shift gear on certifying eVTOLS by revising it certification requirements for eVTOLS from small aircraft to a powered-lift category.
With the growing number of issues to resolve before eVTOLS are able to fly, so to do concerns about the viability of the eVTOL market.

Submission + - Teardown of Russian drones finds off-shelf components, jerry rigged instalation (petapixel.com)

Submitted by wired_parrot
wired_parrot writes: After the Ukrainian army captured one of Russia's Orlan-10 unmanned aerial vehicles, they decided to do a teardown of it. Their findings show a remarkable amount of jerry rigged installations using off the shelf components, including the use of a Canon DSLR camera as the main image capturing sensor.
The Ukranian army posted a video of its teardown on Youtube for those interested.

Comment Priorities (Score 5, Insightful) 51

Yes, because when there is a brutal crackdown on political demonstrators by a repressive regime, aided by Russian troops in a replay of cold-war era Warsaw pact style military crackdown reminiscent of Prague 1968 or Budapest 1956, my concern should be whether the crypto-techno-elite can still carry out their pyramid-bitcoin scheme....

Comment Re:They don't talk about range/hauling capacity (Score 1) 182

by wired_parrot (#61954913) Attached to: Ford's New Custom Electric Pickup Truck Is a Blast From the Past
That's because this is a one-off concept vehicle. And the concept they are trying to showcase is their electric "e-crate motor", which can be used by anyone with the proper know-how to turn an ICE vehicle into an electric vehicle. The range would depend on the battery used, and this package only includes the motor - presumably, the battery, traction inverter and control system would be for you to source.

Comment Re:I doubt it (Score 1) 298

An aircraft flying over the ocean or in a remote area, line-of-sight communication is not possible, and communication with the drone is typically done over satellite, adding around 500ms of delay. When you add in hardware processing and sensor delays, the total delays on a drone like the Predator UAV can experience latencies of as much as 2s, which is significant enough to create problems during landing and takeoff. According to the Telegraph:

But the two-second delay between a pilot moving a joystick in Nevada and an aircraft responding in Afghanistan is enough to cause a crash during take-off and landing. Crews in Afghanistan control 'launch and recovery’ through direct contact with antennae on the aircraft. Half an hour after take-off, control of the Reaper is handed to a crew in Nevada; half an hour before landing, it returns to the crews on the ground in Kandahar.

The 2s delay is not a problem for a typical Predator mission. In a dog-fight, however, 2s is an eternity and it would mean the drones would be unable to respond effectively to a manned aircraft.

Comment Re:kidding much (Score 2) 171

by wired_parrot (#59746538) Attached to: Researchers Trick Tesla Into Accelerating 50 Miles Per Hour

They did this by simply modifying the speed limit sign with some black tape, turning a "3" into an "8."

It's an interesting hack, but it's basically just saying "look, we found way 1001 how to trick image recognition software". Yes you did. Here's your badge, now take a number and stand in line.

As someone who works with safety critical engineering systems, this raises concerns to me far beyond the image recognition software. It tells me that the Tesla Autopilot software is relying on a single source of data to set a safety critical parameter (speed) - a huge no-no in any safety critical system (see 737 MAX). Even if the sign were read as 85mph, a good driver would evaluate his surroundings and the road conditions before deciding whether to accelerate. Common sense would dictate that a sign indicating a speed well above highway speed levels in a small rural road should not be taken at face value.

One should not be using a single source of data as a key input - and whether that data comes from image recognition software or the mapping software, the basic problem remains that the Tesla Autopilot is vulnerable to a critical safety issue if a single data input is corrupted. Ideally they should be having a combination of image recognition and mapping data, coupled with safety monitoring software to invalidate transient spikes in the data and obviously erroneous values.

Comment Re:What about the existing ones? (Score 1) 229

by wired_parrot (#59644640) Attached to: Boeing Officially Stops Making 737 Max Airplanes

A commercial aircraft cannot be certified if it is not stable in its operational envelope, and they would have been required to fly with MCAS off to meet the longitudinal stability requirements of FAR 25.173. I have a hard time believing that any reasonable pilot would not have noticed an inherent aircraft stability issue during certification flight test. It is, as the poster said, less stable at high angles-of-attack due to the engine placement, but still stable nonetheless. The main reason for MCAS was not for stability, but to maintain the aircraft stall characteristics similar to the earlier 737 models and eliminate pilot training.

Note also that the 737 is not the only aircraft type with this type of automated pitch trim command. The airbus A300 has a mach trim and angle-of-attack trim compensation that automatically moves the horizontal stabilizer to compensate for the aircraft pitch down tendency at high mach numbers and high angles-of-attack.

Comment Technical knowledge but not a specialist (Score 2) 155

by wired_parrot (#59637446) Attached to: Do Engineering Managers Need To Be 'Technical'?
A good engineering manager has to have a broad technical knowledge, but he does not need to be a specialist in his field. He needs to be a generalist that understands well how all the specialties underneath him integrate together, and how these disciplines interact with other groups. It is key that he has a good enough technical knowledge of those working under him so he can communicate their needs and requirements to upper management. It is also important to have a broad understanding of the overall field he is working in so he can understand the impact any engineering change from other groups will have on his or her own department.

Comment America's first silicon valley (Score 4, Informative) 144

Actually, it is California that is America's second silicon valley. Up to the 1950s, most of America's electronic industry were centered around the New Jersey-New York metropolitan area. Edison's Menlo Park, Bell labs and GE's Research lab were all based in the area. It wasn't until Shockley moved to northern California in 1956 to start Shockley Semiconductors that northern California began displacing the NY-NJ metropolitan area as a tech sector hub in the U.S. So in essence this is just a return to tech's roots.

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