While Delta provided few details about the explosion, which is under investigation, here is what we know. Mechanics removed the tire from a Boeing 757 and transferred the wheel and tire assembly to the wheel and brake shop. I walked past that shop hundreds of times during my stint at TechOps, and to think about a tragedy of this magnitude is quite surreal.

• READ MORE: Two Killed in Delta Aircraft Tire Explosion

“It is a little bit alarming because this stuff doesn’t happen every day or every week or even every month,” Kyle Bailey, a former FAA safety expert and aviation analyst, told Atlanta Fox affiliate WAGA-TV. “These things explode, these things malfunction, people make mistakes. But sadly, in this case, two people were killed.”

I can attest that I have been an A&P mechanic for over 30 years, and 99 percent of things go off without a hitch. Unfortunately, when things go wrong in aircraft maintenance, they go terribly wrong.

Keep Your Head on a Swivel

In navigating the dangers of aircraft maintenance, it’s critical to maintain situational awareness, or “keep your head on a swivel,” according to the National Aviation Academy.

When my father worked for United Beechcraft at Fulton County Executive Airport/Charlie Brown Field (KFTY) in the early 1990s, a mechanic called for help holding a breaker bar so he could break down a King Air wheel and tire assembly. Having neglected to deflate the tire, it exploded, resulting in the death of a helper. 

Deflation is a vital step in changing a tire, according to a tip sheet compiled by industry professionals and circulated by the FAA. 

“Remove the air from the tire,” it says. “Warning: The tire will be deflated even though the size will not change. Deflate first to avoid any hazards. This is to be accomplished before the wheel is removed from the aircraft.

California Department of Public Health’s Occupational Health Branch case report 19CA002 offers some insight into what happens if technicians attempt maintenance on an inflated aircraft tire:

A stationary engineer working at an airport died when the tire and wheel he was disassembling exploded. The employees on the previous shift removed the tire and wheel from an airport passenger boarding bridge and placed it in the airport maintenance shop. The victim and a co-worker were removing the nuts and bolts that held the wheel together when the tire and wheel assembly exploded, striking the victim in the head and neck. The valve stem was not removed from the tube within the tire to release the air pressure.

The CA/FACE investigator determined that to prevent similar future incidents, employers with workers who change multi-piece tires should:

●      Implement policies and procedures as part of a safety program to ensure that tires are deflated before wheel disassembly.

●      Remove all pneumatic tires and replace them with solid rubber tires.

●      Consider providing employees with certified commercial tire service (CTS) training or hiring companies with CTS technicians.

The FAA-H-8083-31B Aviation Maintenance Technician Handbook—Airframe offers this caution: “Deflate the tire before starting the procedure of removing the wheel assembly from the aircraft. Wheel assemblies have been known to explode while removing the axle nut, especially when dealing with high-pressure, high-performance tires.”

Shop Safety Considerations

The No. 1 reason accidents happen is the failure to follow procedures, according to John Goglia, an airline mechanic and former National Transportation Safety Board (NTSB) member.

“The best way to prepare an aircraft maintenance team is through structured training,” Goglia said. “On-the-job training is one thing, but what if the guys in the shop have been doing it wrong for years? For example, aircraft tires are a lot easier to roll when inflated, even though they are supposed to be deflated when removed from the aircraft.

“Another thing to consider is that in some instances, mechanics work outside their skill, perhaps on loan from another department due to a surge in workload. Those are particularly at risk.”

In my maintenance days, the entire facility went on lockdown for training if we suffered an incident. We called it a safety stand-down, and nothing happened until we completed the task. 

Human factors, such as stress or complacency, directly contribute to many aviation accidents, the FAA said in its Aviation Maintenance Technician Handbook.

Admittedly, we do not precisely know what happened last week at the Delta TechOp shop. AMTs share a common bond and generally look out for each other.

Accidents happen, and sometimes with tragic consequences. We are duty-bound to understand what went wrong so we can correct it for future generations.

The post Deadly Tire Explosion at Delta Facility Highlights Risks in Aviation Maintenance appeared first on FLYING Magazine.

This is not what a CFI wants to hear when the learner is doing the preflight inspection. The learner was looking at the nosewheel of the Cessna 150, specifically, at a scalloped pattern on the side of the tire. She’d never seen this before—and frankly, in my more than 30 years of flying, neither had I. But I knew ugly when I saw it. 

One of the things I teach my learners is not to be embarrassed about asking for help, or asking a more experienced pilot or mechanic a question about something you find during a preflight. With this in mind I took a photograph of the tire with my smartphone and sent it to an A&P/IA with the text question, “OK to fly?” although I had a pretty good idea what the reply would be.

And I was right. 

The reply came back immediately: NO. A few more lines followed, mostly caveats about tires blowing at awkward moments and inquired if I needed help. I quickly explained the situation and ended with the phrase, “Decision: no-go.”

Although disappointed we could not fly, I was happy the learner had the opportunity to see a less-than-standard tire, because it allowed us to have a discussion about aircraft tires. They take a beating at a flight school, so it’s important for the learner to know what is normal and what is not. There is a reason that the checklist includes “check tires for proper inflation, damage, and flat spots.”

Negative transference—that is, applying information from something similar but different—can bite a pilot, especially with tires. One of the big mistakes made by fledgling pilots, especially those who are renting aircraft, is that they think airplane tires are the same as automobile tires, according to Randy Hedrick, customer support engineer for Michelin Tire. 

“Car tires have a wear bar. Aircraft tires don’t,” Hedrick said, noting that the flight students may not realize the aircraft tires are worn to the point of impending failure or more commonly, improperly inflated. 

“We recommend doing a pressure check before the first flight of the day. It’s normal for tires to lose pressure during the day, [so] losing up to 5 percent in two to four hours is acceptable.”

Renter pilots often don’t check the pressure of the tires as part of the preflight inspection. Improperly inflated tires can cause vibration—and that will definitely get your attention during ground operations, especially during takeoff and landing. 

Can You Change the Tire?

Most flight schools keep spare tires stocked, especially when they are also an FBO and have a visiting aircraft in need of maintenance. If they have a replacement tire, you have the tools, and it is your aircraft, so the FARs permit you to change the tire. But please don’t try to do it unless you have the proper tools and know how. 

Every mechanic contacted for this story said the same thing: It’s best to have someone with experience (like an A&P) show you how to do it at least once. There are more steps involved when changing an aircraft tire than there are when changing a tire on a bicycle or automobile, and different techniques and the right tools are a must.

For starters, you need to chock the other tires, find the jack point on your aircraft, and then have some blocks of wood to balance the jack. You have to be careful as you jack up the airplane and reposition the jack because the tire may move in.

Once the airplane is jacked up and the tire off the ground, you have to cut the safety wire. This releases the bolts that hold the brake pad in place, allowing you to take the wheel apart. That’s right—take the wheel apart.

The inner tube can take on a life of its own. Be very careful about the valve stem and be sure the tire tube is not kinked or folded. Installing the tube, whether new or used, involves talcum powder to guide in the inner tube. You have to be careful not to allow the tube to crease or fold, because that can introduce uneven wear, which you will feel when the tire rotates during ground operations.

These are just a few of the things we were warned about. There are many more steps to it, and even if you’ve done it before, you’ll probably want your A&P to check your work. You also need to log the tire change in the aircraft maintenance log.

Even putting air in the tire is not as straightforward as it is with cars. With automobile tires you find the pressure printed on the sidewall. On an airplane, that information is printed in the aircraft’s pilot’s operating handbook or airplane flying manual. Be able to find that information, noting the pressure for the nosewheel and main gear are usually different. 

Always verify those numbers before you ask someone to put air in the tires.

Flight School Tire Challenges

The flat spot is the most common issue found on flight school tires. This is caused by slamming on the brakes and locking them up.

Flat spots can be a challenge to see if the aircraft has wheel pants, so be ready to gently roll the aircraft forward by hand and check the tires all around during the preflight inspection. If the chords are showing through the tread, it’s usually a no-go situation. But there are some pilots who want to make the flight so badly that they get hit with an invulnerability stick and take the aircraft out anyway.

Please don’t be this person.

When you report an issue with a tire to the flight school you expect the maintenance crew to take a look at it. Most of them are good about this, as the aircraft doesn’t make any revenue when it is sitting on the ground.

If you are skeptical that the tire has been inspected, you can do the old chalk trick – make a line on the tire with chalk. If the tire is inspected the chalk line should disappear as the tire rolling over the ground will erase the mark. If the chalk line remains, the tire was not checked.

The post What You Need to Know About Tires When Learning to Fly appeared first on FLYING Magazine.

The role of an A&P is a challenging one with diverse job opportunities. Although they will often have a specialization, A&Ps are certified to work on all parts of all types of aircraft, ranging from widebody commercial airliners to small two-seat helicopters.

A&Ps are also sometimes referred to as aircraft mechanics or aviation maintenance technicians (AMTs). They can work for a variety of employers, ranging from flying schools to airlines to aircraft maintenance contractors.

Prospective A&Ps need to obtain a combination of training and skills before they can be certified by the FAA. Here are the four main steps to becoming an airframe and powerplant technician:

Meet the Basic Eligibility Requirements

To be an A&P, you must be at least 18 years old and be able to read, write, speak, and understand English.

Although you can obtain the technical skills required to be an A&P through training, you should also ensure that you have soft skills that will help you succeed in the field of aviation maintenance. These include strong communication skills and attention to detail.

Gain Formal Training or Experience

The FAA requires prospective A&Ps to meet either a training or experience requirement in order to be certified. There are three ways to meet this requirement:

• Completing the training requirement is the most common option, but also requires you to pay for the program. To meet this requirement, you will need to attend and graduate from an FAA-approved aviation maintenance technician school.
• Those with experience in the military have the option of completing a Joint Service Aviation Maintenance Technician Certification Council training course instead.
• Alternatively, you can complete 18 months of practical work experience with either airframes or powerplants, or 30 months of experience with both systems. Although this option may seem the most practical, entry-level apprenticeships can be hard to come by.

Pass the Required Tests

After meeting the training or experience requirement, a prospective A&P will need to complete the required FAA testing. First, there is a set of three knowledge tests. Once you pass these tests, there is an oral test and a practical test.

Get Certified by the FAA

After completing all the steps listed above, you can obtain your FAA certificate. The A&P certificate has no expiration date and does not require any medical testing.

The FAA certificate actually has two ratings—airframe and powerplant. Most mechanics will obtain both ratings, thereby earning the A&P designation.

FAQs

What is the salary for an airframe and powerplant technician?

According to the Bureau of Labor Statistics, the median salary for aircraft mechanics in 2023 was $75,400. The median annual pay for those working at airlines was $101,500.

Are airframe and powerplant mechanics in high demand?

Yes, there is high demand for A&Ps across the United States and around the world. The Bureau of Labor Statistics anticipates 4 percent growth for aircraft and avionics mechanics through 2032 and aviation training company CAE projects a need for 138,000 AMTs by 2033.

How long does it take to become an airframe and powerplant technician?

The timing depends on which training or experience requirement you choose and how long it takes you to complete the testing. A&P school programs typically range in length from 14 to 24 months. 

The post How to Become an Airframe & Powerplant Technician appeared first on FLYING Magazine.

And while I have, over the years, become adept at coping with such challenges like an adult, the exasperation I recently felt when fighting the sheet metal screws that secure my engine cowling in place on an otherwise beautiful day truly tested me.

It’s not that the engine cowling is complicated. On the contrary, it’s simply two very lightweight aluminum shells that fasten to the airplane with an assortment of various screws. To remove the cowling, one simply unscrews each of them, and each half can then be gently lifted away from the airplane. To reinstall the cowling, the process is reversed. Should be no big deal.

When hobbled by a near-complete lack of mechanical ability, however, things become a bit more complex. 

It’s my own fault. Growing up, my focus was on the piles of books and magazines that littered my room, and any opportunity to patiently focus on learning basic mechanical skills outside or in the garage tended to be quickly tossed aside in favor of more time reading FLYING or Car and Driver magazines.

Accordingly, my mechanical ability became—and remains—somewhat stunted. 

On the day in question, I was attempting to reinstall the engine cowling, and those sheet metal screws were fighting me every step of the way. Some weren’t long enough for the threads to take hold. Others spun in place, refusing to tighten like the threads were stripped. Still others seemingly hit a stop after a few turns, stubbornly refusing to tighten at all.

It was infuriating, and I was getting to the point where I would have to surrender altogether and beg my mechanic to come save the day.

That’s when I remembered one of the single greatest features of my airplane—the friendly, seven-day-a-week support and knowledge hotline, otherwise known as Dick, the airplane’s former owner.

Dick and I keep in touch pretty regularly. Having purchased the airplane from his friend some 40 years ago, he has over half a century of familiarity with it. When the time came to hang things up and sell it to me, I could tell it was difficult for him to say goodbye to his trusty friend. 

To help ease the pain, I promised to give him a call from time to time to update him on things. Since then, we’ve talked every couple of months. Our chats typically last an hour or more, the seesaw of conversation tipping back and forth between his experiences with the airplane in the past and my learning curve in the present. 

Despite having sold it to me, he continues to harbor a deep sense of ownership for the 170.

Once, when I mentioned that the engine had developed a small oil leak, his reaction was one of shock and deep offense. He could hardly believe that the engine he had taken care of so well had the audacity to misbehave in such a manner, and he wanted answers. Fortunately, fixing the leak was a simple matter of replacing a crush washer, and all was well.

Time and time again, Dick has demonstrated how he’s a walking encyclopedia of 1953 Cessna 170B, serial number 26053.

Right-side fuel drain acting up? Ah, yes, he recalled, he replaced that one back in ’85, so it’s probably due. Brake rotors looking kind of thin? Well, even though he’s only really ever used them to help steer on the ground, they’ve been on there since the Carter administration.

So when the profanity subsided during the Engine Cowl Screw Incident of Summer 2024, I caught my breath, wiped the sweat from my brow, and decided to call my lifeline for help. It didn’t take long for Dick’s friendly, easy-going manner to bring me back down to earth.

And as usual, he managed to explain things in a way that made me feel smarter than I am.

First, he had me spread all the screws out in a big container. Then, he began to point some things out. See how there are a few screws that are shorter in length? Those go up front by the left intake to better clear the forward left valve cover where there’s virtually no clearance. 

Oh, yeah. I guess those must have been the ones that weren’t biting or tightening down in other places. 

Notice how the thread pitch is slightly different on a handful of them? Back in 1983, he converted the forward sheet metal screws and Tinnermans to machine screws and floating nut plates. This provides a more secure attachment up at the front of the cowl for safety.

Oh, yeah—those threads are indeed a little different. That would explain why I was unable to thread so many of them into place. 

Dick methodically and clearly educated me on these finer points of the airplane, effectively talking me down from the ledge of incompetence and helping me to understand yet another mechanical aspect that had, up until that point, completely eluded me.

We chatted for a while longer, talking about flying, sharing some laughs, and updating each other on the latest happenings in our lives. 

It occurs to me that among all the criteria one must consider when evaluating various airplanes to purchase, the friendship and support from a previous owner is one factor that is completely unaccounted for.

Classified ads don’t include the previous owner’s demeanor or friendliness. There’s no way to evaluate whether that person would be willing to help out with information or advice in the future or, indeed, whether they are even the kind of person with whom you’d like to stay in touch at all. 

Perhaps it’s for the best. Because if such an evaluation system were in place and widely used, Dick would have increased the value of my airplane to a level well beyond my financial capability—and I’d never have been able to buy it to begin with.

The post Life Lessons and Surviving a Fight With Sheet Metal Screws appeared first on FLYING Magazine.

According to WSB-TV, one Delta employee and a contractor were killed as they were removing the tire.

Another airline employee was seriously injured as a result of the incident. In a statement to the news outlet, Delta confirmed the report.

“The Delta family is heartbroken at the loss of two team members and the injury of another following an incident this morning at the Atlanta Technical Operations Maintenance facility (TOC 3),” a Delta spokesman said. “We have extended our full support to family members and colleagues during this incredibly difficult time…The Delta family is grateful for the quick action of first responders and medical teams on site. We are now working with local authorities and conducting a full investigation to determine what happened.”

Few details are available as to what caused the incident. The involved aircraft is reportedly registered as N683DA, a 31-year-old Boeing 757-200 that had just flown from Las Vegas to Atlanta on Sunday evening.

Editor’s Note: This article first appeared on AirlineGeeks.com.

The post Two Killed in Delta Aircraft Tire Explosion appeared first on FLYING Magazine.

Becoming an AMT can lead to a lucrative and rewarding career. However, there are some important skills that prospective AMTs need to possess.

A Willingness to Learn

There is a steep learning curve for new AMTs. Not only do they need to complete their academic training, but there is also extensive on-the-job training. Learning and development is also a career-long process, with AMTs being required to stay up to date on new directives, procedures, and practices.

Teachability and adaptability are therefore valued traits in the world of aviation maintenance. Prospective AMTs need to be willing and able to absorb new information and apply their newfound knowledge and skills in a practical environment.

Attention to Detail

Pilots, crewmembers, and passengers rely on the hard work of AMTs for aircraft safety and reliability. With such important responsibilities, AMTs must have strong attention to detail when conducting their work.

Small mistakes can have serious consequences when it comes to aircraft maintenance. With larger aircraft now having millions of parts, the work of AMTs is often complex and detail oriented.

Flexibility

The work environment of an AMT can be dynamic and challenging. While AMTs often perform routine scheduled maintenance, the nature of the work also means that they are called upon when things go wrong.

Whether an aircraft is grounded due to an unexpected maintenance issue, or a new problem is discovered during a routine process, AMTs must have the ability to adapt to changing situations.

Many AMTs will work in a 24/7 environment, especially if they work for an airline. Companies will often perform maintenance at night when many of their aircraft are not flying. Prospective AMTs need to be prepared to work shifts around the clock and on evenings, weekends, and holidays.

Ability to Work Independently and on a Team

Although AMTs can work in different types of environments and workplaces, they typically work as part of a larger operation. Large airlines or maintenance providers, for example, could have dozens or even hundreds of AMTs working in a facility at any given time.

AMTs can work on all parts of an aircraft, ranging from the engines to the pilot seats. Given the wide range of potential tasks, AMTs have to be able to work well on their own and as part of a larger team.

Strong Communication 

Effective communication is important in most workplaces, but it is particularly crucial when safety is involved.

Not only do AMTs have to communicate with their maintenance colleagues, but they often have to work closely with pilots, crewmembers, supervisors, and other professionals within their company. Having the ability to communicate well, both orally and in writing, is a major asset for an AMT.

Technical Skills

The work of an AMT is inherently technical and requires extensive knowledge and training. Many of the technical skills needed to be an AMT are obtained through formal training.

However, there are also valuable skills that can be developed outside of the field of aviation maintenance. For example, strong math abilities or a good grasp on diagrams and patterns can greatly benefit a prospective AMT.

Physical Skills

Being an AMT is a physical job that requires a certain level of stamina and dexterity. AMTs may have to stand for long periods of time, work in confined spaces or awkward positions, and operate a variety of tools and equipment.

While many of these skills can be developed through training and experience, it can help a prospective AMT to be in good physical shape and have a general understanding of how to use tools and power tools.

Do You Have What It Takes to Be an AMT?

Being an AMT requires a certain set of skills, abilities, and knowledge. While many of these can be obtained with training and experience, others require personal development and growth.

The post What Skills Do You Need to Become an Aviation Maintenance Technician? appeared first on FLYING Magazine.

This is the 100th installment of The New Owner, and I suppose it’s only natural that the milestone is occurring amid a maniacal blend of emotions swirling around said ownership.

On one hand, EAA AirVenture in Oshkosh, Wisconsin, is next week (July 22-28), so there’s massive excitement for epic times just ahead. On the other hand, some maintenance issues have arisen over the past couple of weeks that create severe trepidation and directly threaten those amazing times.

It’s a perfect representation of aircraft ownership as a whole. Amazing experiences put at risk of derailment from unforeseen circumstances, fighting back and forth like so many Hollywood heroes and villains. But instead of the villains threatening the powers of good with swords, guns, and death rays, the threats come in the form of grounded airplanes and massive repair bills.

Frankly, I’d prefer to take my chances with the guns and death rays.

• READ MORE: Airplane Types Unlock AirVenture Locations for Parking, Camping

The first sign that something was amiss came several days ago in the form of engine oil. More specifically, a few extra drops on the hangar floor, slightly higher consumption than normal, and a new sheen collecting on the bottom of the engine. It wasn’t that my Continental engine was leaking oil. That’s pretty typical for most old Continentals. It was that mine was quite suddenly leaking in new places, at higher volumes, much differently than normal.

At any other time of year, it would be a simple matter of postponing future flights and booking some time with my mechanic. But this was Oshkosh month, a time when the severity of any mechanical problems increases exponentially as the date of the magnificent fly-in nears. And being that the big event was only a couple of weeks away at this point, panic quickly set in.

I immediately texted my mechanic, Ryan. He’s a great guy who embodies rural Wisconsin friendliness and honesty. He’s the kind of person who will bend over backward to help you and happily provide educational lessons about the tasks he’s performing along the way. He and his brother own and operate Johnson Brothers Flying Service in Lone Rock, Wisconsin, about 40 miles west of Madison.

While I was waiting for his reply, I examined my engine. I couldn’t quite pinpoint the source of the oil, but I suspected my Continental C-145 was experiencing weepy pushrod seals. This is a known issue with the type, as well as with the later version, the O-300.

I’ve always been amused at the engine’s midproduction name change from C-145 to O-300. Continental evidently figured that referring to the engine by the displacement (300 cubic inches) made it sound more powerful and impressive than referring to it by the 145 hp it produces. Marketing 101, I suppose.

Ryan replied that he would try to make it out sometime during the week before my departure to Oshkosh. But because he was so busy, he couldn’t guarantee it. I’d just have to wait and hope. In the meantime, I opted to remove my upper and lower cowls for a closer inspection.

To someone like me with close to zero mechanical aptitude, dismantling your airplane’s upper and lower cowls to reveal an entirely naked engine is simultaneously empowering and intimidating.

In one respect, it makes you feel like you know what you’re doing. Anyone walking past the open hangar door would naturally assume you possess some rudimentary level of knowledge and proficiency. But in another respect, you’re pretty sure you’re fooling nobody.

For the purposes of an engine inspection, however, it worked out just fine, and I was able to trace the leak to the oil temperature probe on the back of the engine accessory case. I forwarded this intel to Ryan.

The next afternoon, I received a text from him. Unbeknownst to me, he made it out to my plane and addressed the leak. I was ecstatic and headed right out to the airport for a shakedown flight prior to my trip up to Oshkosh.

Sure enough, the oil leak appeared to be taken care of. I preflighted the airplane, pulled it out of the hangar, and hopped in—only to discover that the throttle was inexplicably encountering some kind of blockage halfway into its travel.

Thinking that a running engine might somehow solve the problem, I started it up but found that nothing had changed. The throttle knob would only advance about halfway to full throttle before encountering a hard stop.

Now, things were getting serious. It was a Friday evening, less than a week before my planned departure to Oshkosh. Ryan was busy and wouldn’t be able to chat until Sunday or Monday. Desperate not to miss the big event, I gave my friend Dan a call.

“Hey, man, have you sold your Ercoupe yet?” Dan replied that he had not. “And you’re not going to make it to Oshkosh this year, right?” “That’s right,” he replied. “We’ll be in Michigan all week.”

• READ MORE: Flying In to AirVenture: A Carefully Orchestrated Cacophony of Chaos

He knew I was angling for something, so I explained.

“I’m dealing with some mechanical issues on the 170, and I’m not sure if it’ll be fixed in time for Oshkosh,” I said. “If it’s not, how about I take the Ercoupe up and hang some of those big ‘for-sale’ signs on the prop so a half million people see it?”

After considering this for a moment, Dan agreed that it would be a win-win sort of situation.

With a backup plan firmly in place, Saturday came and went. On Sunday morning, I received a text from Ryan. He was available to zip out to the hangar and have a look at my throttle issue.

The fix took him all of about five minutes. He explained that he must have inadvertently dislodged part of the throttle cable while inspecting something else during the oil leak work. He assured me it wasn’t likely to occur again and said he’d be entirely comfortable flying it. He also said that because it was his fault, he wouldn’t be charging me for the trip out. I gave him a 100-dollar bill anyway to show my appreciation.

At the time of this writing, I have just about everything packed up. My tent, sleeping bag, cooler, chairs, underwing party lights, and coffee supplies are ready to go. This afternoon, I’ll fly a shakedown flight to check for any errant oil leaks and confirm all is in order. With any luck, I’ll be flying my own plane up to Oshkosh tomorrow and, much as I sincerely appreciate Dan’s offer, hopefully not an Ercoupe.

If you wonderful readers will also be at Oshkosh next week, please come find me. I plan to be somewhere around Row No. 67, right up on the airshow crowd line. I’d like to thank you in person for your readership and support over the past few years and give you a sticker or two.

Just look for the blue 170 with Alaskan Bushwheel tires. Or, depending on how things go, a classy little Ercoupe.

The post When Unforeseen Circumstances Threaten to Derail Amazing Experiences appeared first on FLYING Magazine.

The issue of what is legal (in FAA terms) and approved (by manufacturers) puts maintainers in a sticky situation. On one hand, the FAA issues a supplemental type certificate (STC) allowing for products to deploy on aircraft, but the engine and/or aircraft manufacturer may not approve or recognize the STC as something permitted for use under the terms of their warranty. 

Whether an aircraft owner or operator chooses to use the alternate fuel or not is a matter of choice. The fuel has been approved by the FAA and is perfectly legal to use in the SR series aircraft. The dilemma for the maintainer arises upon returning a Cirrus aircraft to service even for something as routine as an oil change. 

• READ MORE: Identifying Corrosion in All Its Forms

Consider this scenario. The pilot opted to refuel with G100UL or the aircraft arrived with G100UL in the tank. This alternate fuel is a drop-in replacement, so 100UL could have been added to 100LL already in the tank. Granted the maintenance action in this case did not involve fuel, but the maintainer is signing for the entire aircraft to be returned to service. If they sign the repair IAW OEM guidelines, this includes Service Advisories (including one that prohibits the use of G100UL fuel). Consequently if the aircraft is carrying G100UL, then this could be an issue because the aircraft is not being returned to service IAW this Cirrus SB.

Of course, as with any guideline, the issue of signing for an aircraft is subject to interpretation. I know mechanics that will only work on aircraft they have personal history with and do not want to return to service an inherited unrecognized maintenance action.

In the advisory (SA24-14) “Transition to Unleaded Fuel and Use of Non-Cirrus Approved Fuel in SR Series Aircraft” released June 18, Cirrus said it was committed to the industry’s transition to unleaded fuels, which is underscored by its collaboration with stakeholders such as the Aircraft Owners and Pilots Association (AOPA), General Aviation Manufacturers Association (GAMA), FAA, and Eliminate Aviation Gasoline Lead Emissions (EAGLE) industry initiative.

Aircraft and engine manufacturer’s are extremely risk averse. They historically do not recognize alternate methods of airworthiness, and this includes STCs, parts manufacturer approval (PMA) parts, and designated engineering representative (DER) repairs.

There is a commercial element to this since any aftermarket PMA part procured from a third party is a revenue lost for the OEM. It appears the reason for the SB in this specific case is Cirrus’ concern about the breakdown of a fuel tank sealant that was seen in an isolated (one) aircraft known to have been fueled with G100UL.

The company will need to vet this against other aircraft in the fleet to ascertain if the perceived breakdown is an isolated outlier related to the drop-in fuel, or if the dislodged fuel tank sealant was a manufacturing defect unrelated to the use of G100UL. 

• READ MORE: 5 Attributes of a Top-Notch Maintenance Provider

“While some aspects of the initial Cirrus testing of the GAMI G100UL fuel are encouraging, other areas, including materials compatibility, remain inconclusive,” the advisory said. “At this time, Cirrus does not approve the use of GAMI G100UL fuel in Cirrus SR Series airplanes. Per Continental and Lycoming, only approved fuels may be used for an engine to be covered by warranty.” 

According to the FAA, G100UL is safe to use, hence the STC approval. This took years of testing to clear the milestones. In fact GAMI uses the fuel in its company SR22..

According to GAMI, the fuel has undergone substantial testing and displayed no issues on other aircraft. The company also disputes Cirrus’ claim that using G100UL voids the warranties on engines supplied by Lycoming and Continental, however, the engine manufacturers have confirmed its use could affect warranty claims, according to AVweb. 

Tim Roehl, president of GAMI, indicated that his team is drafting a formal response to Cirrus Service Advisory SA24-14 to be posted on its website. Roehl also said that the sealant Cirrus references is not the polysulfide sealant more commonly used in the industry but a polythioether sealant. Roehl stated that G100UL has been in service since 2010 on one wing of the company’s Cirrus SR22, using the same polythioether sealant Cirrus uses, with zero incidents.

The FAA does not comment on specific OEM warranty policies but the agency has reiterated that GAMI’s G100UL does have the STC approval. This is not uncommon as the FAA routinely approves alternate solutions without the buy-in from OEMs. The burden is on the third-party solution provider to prove airworthiness—i.e. STC holder, PMA manufacturer, or designated engineering representative for DER repairs.

What This Means for Maintainers

This fuel issue places aircraft maintenance professionals in a bit of a quandary. On one side, you have the FAA approval for G100UL, but at least one aircraft manufacturer, Cirrus, and one engine manufacturer, say they are not approved via service advisories.

The FAA typically steers clear of airframe/powerplant OEM issues until they become an airworthiness directive (AD). To assist in clearing any confusion, the agency issues periodic documents to help owner/operator/maintainer stay abreast of the situation. One such publication is the FAASTeam service bulletins.

When asked if service bulletins are mandatory, the FAA says: It depends. 

Here is a quick agency ruling: “If you are operating your aircraft under 14 CFR part 91, a service bulletin is advisory, and compliance is not mandatory unless it is included in an Airworthiness Directive.”

Another resource is FAA Advisory Circular AC 20-114, which addresses manufacturers’ service documents: “Service documents should be neither treated nor represented as the official FAA approval documents, unless either a letter of design approval from the FAA or a record that compliance has been determined by an FAA designee is on file for recommended actions indicated as FAA-approved in service documents.”

That said, service documents are beneficial and transmit a wealth of knowledge. When returning aircraft to service, it is critical to list if the action is in accordance with OEM information or another alternate form of maintenance. This comes into play when installing PMA parts, or an STC like G100UL.

The post Cirrus Service Advisory Throws Fuel on G100UL Maintenance Debate appeared first on FLYING Magazine.

Diving deeper into the world of aviation spark plugs, we will pull back the cowling and affix our inspection mirror to discuss the types commonly used in different aircraft models, insights into their maintenance, and recommendations for their replacement. 

Understanding the Basics

At their core, spark plugs are devices that deliver electric current from an ignition system to the combustion chamber of an engine, igniting the compressed fuel/air mixture by an electric spark. Properly functioning spark plugs are essential for smooth engine operation and optimal performance.

Types of Aviation Spark Plugs

“The two major types of electrodes in today’s spark plugs include the dual nickel alloy massive electrode and the single Iridium fine-wire electrode,” saidAlan Woods, sales manager for piston and power at Champion Aerospace in Liberty, South Carolina. “The nickel alloy electrode design allows for a long-lasting spark plug [300 to 500 hours] at an affordable price. The Iridium fine-wire electrode design offers TBO life [2,000 hours plus] but at a higher cost due to the high cost of Iridium [$4,000 per ounce].”

Massive Electrode Spark Plugs

Massive electrode spark plugs are the most commonly used type in general aviation. They feature large electrodes designed for durability and extended use.

• READ MORE: Intro to Aviation Spark Plugs

Massive electrode plugs are critical features in terms of durability. They can withstand significant wear and tear, making them ideal for aircraft that undergo frequent and long flights. Massive electrode plugs are also cost-effective. They are generally more affordable than their counterparts, the fine-wire spark plugs. Another attribute is their ease of maintenance. Due to their stout construction, massive electrode plugs are easier to clean and maintain.

There are a few downsides to massive electrode plugs. Over time, massive electrode spark plugs can suffer from performance issues due to electrode wear and increased gap size, leading to less efficient combustion. They are also heavier as the larger electrodes add to the weight, which can be a minor concern in aircraft performance calculations.

Fine-Wire Spark Plugs

Fine-wire spark plugs are designed with thinner electrodes, often made of precious metals such as platinum or Iridium, to provide superior performance and longevity.

The fine-wire plug offers improved ignition over massive electrodes, giving the fine-wire electrodes a more concentrated spark and leading to better combustion and engine performance. They also last longer because they are constructed using durable materials, such as platinum and Iridium, reducing the frequency of replacements. Fine-wire plugs are also lighter than massive electrode plugs, contributing to overall aircraft efficiency.

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These enhanced attributes come with a cost. Aircraft fine-wire spark plugs are substantially more expensive than massive electrode spark plugs. They also require careful handling during maintenance to avoid damaging the fine electrodes.

Choosing the Right Spark Plug 

The choice between massive electrode and fine-wire spark plugs often depends on the specific requirements of your aircraft and your flying activity. Massive electrode spark plugs might be more suitable if you fly frequently and cover long distances due to their durability and cost-effectiveness. Fine-wire spark plugs could be the better choice if you prioritize engine performance and are willing to invest in premium parts due to their enhanced ignition efficiency and longevity.

Fine-wire plugs provide a more efficient burn rate and last longer at a much higher purchase price, according to Vince Bechtel, director of aftermarket sales at Tempest Aero Group, which entered the aviation spark plug market in 2010 by acquiring the Autolite brand. A relatively small niche market, the company represents about 10 to 15 percent of the aviation aftermarket. Turbocharged aircraft flying at higher altitudes favor fine-wire plugs, according to Bechtel.

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Maintenance and Replacement Recommendations

Proper maintenance and timely replacement of spark plugs are crucial to avoid engine misfires and ensure smooth operation. Some tips:

●      Regular inspections: Conduct routine inspections every 100 hours of flight time or as your aircraft’s manufacturer recommends. Check for signs of wear, fouling, or damage. Common issues include carbon buildup, oil fouling, and electrode erosion.

●      Cleaning: Use an approved spark plug cleaner to remove carbon deposits and debris. Be cautious with fine-wire spark plugs to avoid damaging the delicate electrodes.

●      Gap checking: Ensure the spark plug gap meets the manufacturer’s specifications. A correct gap is crucial for optimal spark plug performance. Adjust the gap if necessary using appropriate tools.

●      Replacement: Replace spark plugs at the manufacturer’s recommended intervals or if significant wear or damage is observed during inspections. Always use spark plugs that meet the specifications of your aircraft’s engine model.

“Honestly, the biggest issue I see is over-cleaning,” Bechtel said. “Individuals and shops tend to clean plugs until they look brand new out of the packaging. The only thing this does is wear out your electrodes and insulator faster, preventing you from getting the full life out of a set of plugs.”

Troubleshooting Common Spark Plug Issues

Even with regular maintenance, spark plug issues can occur. Some common problems and their potential causes include:

Engine Misfire

• Caused by worn electrodes, incorrect gap, or fouled plugs.
• Solution: Inspect, clean, or replace the spark plugs as needed.

Hard Starting

• Often due to spark plug fouling or improper gap.
• Solution: Check and clean the spark plugs and correct the gap.

Poor Engine Performance

• Can result from degraded spark plugs or incorrect heat range.
• Solution: Verify that you are using the correct type and heat range of spark plugs for your engine.

The introduction of fired-in suppressor seal technology, or FISS, is a recent advancement in aircraft engine spark plugs.

“This technology eliminates the high-voltage silicon resistor, which is prone to resistance value increases over time,” Woods said. “The FISS technology incorporates fired-in conducting and suppressor glasses that establish the resistance value of the spark plug. This means that the end user has a stable resistance value over the entire life of the spark plug. With the introduction of electronic ignition, spark plug designs will evolve with wider gaps to handle the increased energy being produced.”

Understanding the various types of aviation spark plugs and their benefits and limitations can help you make informed decisions about aircraft maintenance. Whether you choose massive electrode spark plugs for their durability and cost-effectiveness or fine-wire spark plugs for their superior performance and longevity, regular maintenance and timely replacements are critical to engine operation. 

Please consult your aircraft’s technical publications and an A&P mechanic to ensure your spark plugs are in an airworthy condition.

The post Keeping Current With Aviation Spark Plugs appeared first on FLYING Magazine.

Answer: According to the FAA, aircraft used by Part 141 pilot schools must be maintained under the same requirements as aircraft operated under Part 91. FAA regulations allow someone who does not hold a mechanic or repairman certificate to perform certain preventive maintenance under Part 91.

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The regulation you are referring to applies to a certificated pilot. That is a private pilot, sport pilot, or higher—a student pilot is not a certificated pilot, therefore the student pilot doing preventative maintenance on an aircraft would not be permitted. In addition, 14 CFR Part 43 notes that maintenance can only be done when the aircraft is not used under 14 CFR Part 121, 127, 129, or 135. If the flight school also uses the airplanes for charter operations (Part 135), that’s another reason you cannot touch them.

The post Can Student Pilots Perform Preventative Maintenance on Aircraft? appeared first on FLYING Magazine.