Boeing 737 MAX Cleared for Flight Once Again

The Boeing 737 Max received approval from the Federal Aviation Administration to reenter commercial service on Wednesday morning, after being grounded for 20 months following two fatal crashes.

American Airlines is currently the only airline that said it will fly the Boeing 737 Max in 2020.

This approval marks the end to one of the longest aircraft groundings in history. After U.S. regulators were forced to ground the plane in 2018 when two crashes killed 346 within the same year.

In October 2018, Lion Air Flight 610 was 13 minutes into its flight when it crashed into the Java Sea off the coast of Indonesia. Not even five months later, Ethiopian Air Lines Flight 302 crashed near Addis Ababa airport six minutes after takeoff, killing everyone on board.

An automated flight control system misfired on both occasions, leaving the pilots struggling to regain control over the aircraft and its altitude. This program was not mentioned in the pilot manual because the aircraft was marketed as an airliner that would require very little pilot retraining.

In response, Boeing decided to rewrite the entire flight computer software.

While Boeing CEO Dave Calhoun said he believes the Max is "safer than the safest airplane flying today", the challenge facing Boeing now will be rebuilding the public's trust of the aircraft amid allegations that profit was put over safety, the regulation process was broken and Boeing's culture of concealment allowed this fatal flaw to be approved.

American Airlines pilot Capt. Dennis Tajer has been flying commercial planes for more than 30 years, and he told ABC News:

"I'm not walking down that jet bridge, and nor is any other pilot until we've been assured that this airplane will be fixed, it is fully vetted, it is transparent and we are robustly trained," Tajer, who is also a spokesperson for the Allied Pilots Association. "We have yet to see the full training on it."

To understand what went wrong, you need to examine hardware that lead to the aircraft's faulty software:

The Boeing 737 Max was developed and marketed as an alternative to rival Airbus's updated A320neo, which included a "new geared turbo-fan engine" that would make the plane 15% more fuel efficient.

Boeing also wanted to upgrade its popular narrow-body aircraft with the more advanced engines and match the A320neo's marketing that pilots will require minimal training. 

However, unlike the A320, Boeing's aircraft was too short to simply mount the larger engines under the wing. Instead, the company mounted the engines slightly higher on the wing, so the top of the engine sat slightly above the wing. 

This caused the aircraft to pitched too high when the aircraft was at full-throttle, and threatened a stall, so Boeing installed a correction software that lowered the nose automatically if the plane was flown at too high of an angle.

This system was not mentioned in the two-hour iPad training course created for pilots by Boeing, in keeping with their promise that the plane flew just like its predecessor and required little training for pilots to upgrade.

It's this software that became the focus of the Lion Air crash investigation, and ultimately lead to the Ethiopian Air Lines plane crash as well.

Although the aircraft has been officially ungrounded, the soonest the Max can legally fly with paying passengers is December. 

Airlines will need to training their pilots to be ready and confident to fly these planes before any passengers board. This process that could take months.

So far, American Airlines is the only company to announce it will fly the Max in 2020.

Pentagon Begins Rollout for F-35 Logistics System Hated by Maintainers

Last month U.S. Marine Corps Air Station Yuma in Arizona became the first unit to receive parts of a new logistics system that will replace the bugged system in the next two years.

The F-35B squadron received the initial round of hardware to operate the Operational Data Integrated Network (ODIN), which is set to replace Lockheed Martin's troubled Autonomic Logistics Information System (ALIS)  according to the F-35 Joint Program Office.

F-35 Demo Team pilot prepares for takeoff at Hill Air Force Base, Utah.

By December 2022, all F-35 units will have both the new hardware and accompanying software for ODIN, which will allow them to track and order spare parts, conduct repairs, support mission planning and training, store technical data, and perform other functions previously conducted by ALIS.

ALIS was “designed to bring efficiency to maintenance and flight operations, but it does not yet perform as intended,” wrote Director of Operational Test and Evaluation Robert Behler in January 2019.

The system is notoriously hated by maintainers for impeding their ability to keep the joint strike fighters mission-ready with data gaps and bugs that persisted even after years of updates and improvements. It's technology is outdated and slow by current standards as it was developed at the same time as the F-35 aircraft in the early 2000s. 

These problems have caused the military to ground aircraft that are erroneously described by ALIS as not mission capable, slowed down a squadron’s ability to start flying after being deployed, and created a bigger workload for maintainers.

To their relief, the F-35 Joint Program Office reported the new ODIN hardware is demonstrating performance gains. Tests have shown an improvement in the speed of the ALIS software due to the new hardware, with processing times taking roughly half the time it took the legacy hardware.

Maintainers in the Marine Fighter Attack Squadron 211 or 122 conducted five test flights on Sept. 29-30 and are set to conduct more.

In addition to functional advantages, the new system hardware is much smaller than the previous servers supporting ALIS, which can weigh more than 800 pounds.

The ODIN hardware includes only “two transportable cases roughly the size of two pieces of carry-on luggage,” each weighing less than 70 pounds, according to the program office release.

The system is being designed to decrease maintainer workload and increase mission capability rates, according to the program office release.

“The biggest different between ALIS and ODIN is that … the government is leading the ODIN development effort, leveraging the capabilities and the contributions of organizations like Kessel Run, Lockheed Martin, the 309th [Software Engineering Group] out at Hill [Air Force Base in Utah] and others, bringing them together to deliver the apps and the infrastructure and the underlying data architecture that’s required to execute the program,” Lt. Gen. Eric Fick, the government’s program executive officer for the F-35, said in March.

One by one, other squadrons will receive the new ODIN hardware and with a new cloud-native system with applications that can be regularly updated based on user feedback, this system should truly benefit more maintainers than before.

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Engine Manufacturers, MROs see fall in demand amid global pandemic

By now we're all pretty familiar with the challenges airlines are facing amid the COIVD-19 pandemic, and as the lull in airline travel continues, related industries are struggling to find other avenues to recuperate revenue, weaknesses in their business models are coming to light.

Engine maintenance providers - both manufacturers and third-party MROs - have seen a sharp fall in demand for as airlines reduce their activity amid the pandemic, which as exposing a weakness in the industry's overall business strategy.

Maintenance is a key revenue source for manufacturers. Engines are usually sold with substantial discounts through aircraft deals, and they depend on aftermarket services - like overhauls and engine maintenance - to recover the development and production costs.

Long-term, flight-hour-based service agreements are usually arranged with flat-rate fees to manufacturers for engine support, whether action is required or not. In return, the manufacturers support the financial risk in the case of an engine failure. When a failure occurs, the OEM must provide a spare, get the aircraft back in the air, and repair the engine.

As more airliners are parking their aircraft amid the pandemic, engine makers’ aftermarket business has also stopped short.

Cirium data shows daily flight-hours were down 51% for narrow-bodied aircraft and 71% for widebodies on September 30 compared to the year before.

For the flights they do operate, airlines are using their latest, most fuel-efficient aircraft to save money. Most of these aircraft engines are covered inder long-term service agreements with OEMs, so shop visits have dropped.

Cirium reports that work volume at a major European engine overhaul facility has shrunk by 75 percent, and another third-party overhaul shop lost virtually all its scheduled appointments within weeks. 

MROs similarly depend on engine overhauls, as they rank among the most profitable services in that business sector.

Roland Gerhards, chief executive of German aviation research centre ZAL, said the competitive MRO environment will “definitely change”, partly because low aircraft utilisation has put manufacturers and their hour-based service agreements in a “weak” position.

“The engine manufacturers really stand with their back against the wall and are in a bad negotiating position,” Gerhards says.

OEMs are keen on renegotiating the service agreements that mainly work in airlines' favor, based on the hours actually flown. The airlines however, since they are struggling to survive with less flights and fewer flight hours, are in no position to pay higher maintenance fees.

This was made increasingly clear by Rolls-Royce's announcement on October 1 to raise £3 billion ($34.9 billion) of capital through new shares and a bond offering. However, it will not make a fundamental review of its hour-based aftermarket services.

Rolls-Royce told Cirium: “We continue to believe in the benefits our TotalCare agreements offer our customers and we have no plans to change the shape of our service contracts. Rolls-Royce has pioneered long-term service agreements under the power-by-the-hour model in civil aerospace since the late 1990s and it remains very popular today – around 90% of our customers have chosen TotalCare coverage on new to mid-life engine programmes.”

The UK-based manufacturer said on October 1 that it was “re-phasing” investment in its UltraFan future engine program – which involves a geared-fan architecture and new materials. 

Many manufacturers need  investments to develop new technology for future aircraft generations, and with this drop in crucial aftermarket revenue, the timeline for full- or hybrid-electric or hydrogen-fueled power systems has been lengthened.

For now, MROs can count on a significant change in industry business practice.

U.S. Airmen find solution to KC-135, C-130 Battery Testing Failure

The U.S. Air Force announced it has revised outdated procedures for testing the condition of aircraft batteries on the KC-135 Stratotanker and C-130 Hercules to prevent the premature disposal and replacement of batteries.

KC-135 Stratotanker (Courtesy U.S.Air Force)

The solution, found with help from airmen at Rickenbacker Air National Guard Base, Ohio, and Tinker Air Force Base, Oklahoma, reduces unnecessary equipment costs and maintenance delays. The team anticipates the updated procedures will decrease the rate of condemned batteries enterprise-wide, saving the U.S. Air Force an estimated $436,000 in battery-replacement costs annually and approximately 5,280 maintenance hours.

The batteries serve as the aircraft’s backup to power essential equipment should engine generators fail. To date, the Air Force C-130 and KC-135 fleets, more than 600 aircraft globally, operate with the batteries.

The airmen determined by updating the technical guidance and adjusting the required voltage and charging settings for specific processes, the legacy charging equipment can now sync with the modern battery and provide accurate test results. A draft Technical Order is authorized for testing by select field and depot maintenance units. The Air Force Research Laboratory expects to release a formal TO later this year, which will allow all bases to be able to implement the change.

The battery testing issue came to light in mid-2017 when depot personnel at Tinker AFB discover the sealed lead-acid batteries were failing periodic maintenance tests at a rate three times faster than expected.  These batteries, manufactured by Teledyne Technologies, Inc., were required to be rejected and replaced before the end of their service life as a result.

When the depot notified Supply Chain management and AFRL Materials and Manufacturing directorate, they found the 121st Maintenance Squadron was having similar issues. 

According to Defense Logistics Agency data, procurement of battery replacements increased by 50% since the installation of the Teledyne battery.

"We noticed that we had condemned more batteries in six months, than we had in the previous year,” said Tech. Sgt. Jeffrey Frey, 121st Maintenance Squadron electrical and environmental specialist. “The battery is coded as an expendability item, so if they fail maintenance tests, they are thrown away."

Research found there was only an issue during the maintenance checks, as there was no evidence of battery failures in flight. 

Through ground testing and data capture, the team discovered that the maintenance procedures were incompatible with the legacy model of charging equipment and worked with Teledyne and subject matter experts to update technical interim instructions to charge and maintain the batteries. The update instructs airmen to sync the existing equipment and successfully charge and maintain the batteries without requiring any physical modifications to the battery itself.

For more information or aircraft battery options visit Aerospace Electrical or AeroBase Group.

Aircraft Propeller Maintenance

Aircraft Propeller Maintenance

Aircraft Propeller maintenance stars with careful and regular inspection. Even the smallest of areas that may have damage such as nicks and stone chips can allow for stress points that can often and commonly lead to corrosion or cracks. It certainly pays to be vigilant and deal with these small areas of damage before they soon become big ones.

Making simple and minor repairs to propeller blades is not commonly or particularly challenging task, but the technique is fundamental. It’s certainly not something that owners can or should do by themselves. An experienced professional is usually required.

Aircraft Propeller Maintenance

Careful planning and patience is key. It can be typically very easy to remove aluminum from the outside of a propeller blade and nearly impossible to place back on. This is important when you soon realize that each propeller blade has dimensional limits that will restrict the amount of metal that can be take off during repairs before the entire propeller becomes unairworthy.

It’s recommend to use a hand file to carefully remove any damaged material until you eventually reach the bottom of the nick, stone chip, etc. None of the original or primary damaged surface should be left. Only a minimum amount of material should be removed to achieve this.

Next, dress out the repaired area, making sure to create a smooth transition into the surrounding material. The typical rule is to dress out the repair up to an area 10 times the original depth of the damage. For example, if you need to file down one eighth of an inch to enable you to get to the bottom of a nick or chip on the leading edge, you must be prepared to dress out the repair up to five-eighths of an inch on both sides of the center of the repair, which becomes a total repair span of around 1.25 of an inch. It’s recommended that you try to maintain the original airfoil shape, by blending the repair around and into the surrounding area.

You can easily remove file marks by using an emery cloth until the surface becomes smooth. Inspect the area carefully, by using a dye penetrant that will reveal any remaining cracks or marks.

Regular oil changes are fundamental when it comes down to aircraft that house constant-speed propellers. Since engine oil allows for the power source in controlling propeller pitch; it means making sure that the oil is free of dirt and is clean will considerably reduce the chance that the propeller will experience problems caused by water contamination or sludge. It’s recommended to leave constant-speed propellers in a horizontal position or, in the case of a three blade propeller, in a “Y” position to reduce any possible water collection on the hub.

Wooden propellers are most certainly pieces of art, they should be treated with care. Pay particular attention to any metal tips on the ends of the propeller; looking for loose rivets, screws, or solder. The coating of varnish serves a crucial part in protecting the propeller from any moisture damage and should be delicately maintained. If the propeller needs to be removed for any reason, the hub bore and bolt holes should be inspected for any damage. The holes holes should ideally be treated with a preventive against moisture such as varnish.

Nevertheless, regardless of the kind of propeller that you may have, it’s always recommended to perform a tracking check on your propeller. This is a simple procedure that many owners can do.

Copyright AeroBase Group, Inc. 6/1/2015