Aviation Safety - Page 12 Aviation Articles

The Rise of the Angle of Attack Indicator for General Aviation Airplanes


Earlier this year, the National Transportation Safety Board (NTSB) added the prevention of loss of control accidents in general aviation to its Most Wanted List, a list of advocacy priorities the organization releases yearly.

Loss of control accidents (stalls, spins, etc.) made up 40 percent of fatal fixed wing general aviation accidents between 2001 and 2011, according to NTSB statistics. More than 25 percent of all fatal general aviation accidents occur during the maneuvering phase of flight, and more than half of these maneuvering accidents result in a stall/spin scenario. The NTSB continues to emphasize an industry-wide need to focus on preventing these accidents in order to reduce the accident and fatality rates for general aviation pilots. Preventing loss of control accidents should include awareness, as well as educating and training pilots, says the NTSB, and the organization is taking their own advice - in October the agency will host a forum to discuss some of the ways the industry can improve. The topics of discussion will include a statistical review, new training techniques, and equipment and technology improvements, and will most certainly include the installation and use of angle of attack (AOA) indicators in light general aviation aircraft.

Over the past few years, the NTSB, FAA and General Aviation Joint Steering Committee (GAJSC), with support from industry groups like AOPA, have been working together to advocate the use of AOA indicators in light airplanes as a way to encourage recognition and prevention of stall accidents. In the past, pilots and aircraft owners haven’t been all that eager to install them, though, based on cost and the red-tape problems associated with the installation process. In 2014, the FAA streamlined the process of installing AOA indicators, making it easier for aircraft owners to enjoy their benefits.

We know that a stall will occur any time the wing’s angle of attack - the angle between the chord line and the relative wind – exceeds its critical limit. But historically, pilots have been trained to monitor and fly precise airspeeds in order to prevent stalls. This is helpful, but only when the aircraft is in straight and level, coordinated, unaccelerated flight, when the aircraft’s stall speeds are quite low and where they are known and familiar for that particular flight configuration. But an aircraft can – and will - stall at any airspeed, any weight, any configuration, and any attitude when the critical angle of attack has been exceeded. While airspeed is a good guideline to use, it shouldn’t be the only one. Pilots should understand that the angle of attack, which is invisible, matters much more than the airspeed.

Enter the much talked about angle of attack indicator. It’s designed to help pilots determine the aircraft’s true angle of attack in real time, allowing the pilot to "see" the angle of attack in a way that’s not possible otherwise. This will be especially valuable to new pilots, who, through its use, will better understand the concept of angle of attack as it relates to different aircraft configurations and phases of flight.

So what will it take to install an AOA indicator? According to this article on AvWeb, not much. After the FAA approved the more streamlined process, most general aviation aircraft will not require an STC and the modification can be done by any A&P mechanic with just a logbook entry. AOA indicators for small general aviation aircraft like the Cessna 172 cost between $400 - $2000, depending on whether it’s electrical or mechanical, heated or not, pressurized or not, and other variables.

The Importance of Checklists: 4 Accidents That Checklist Use Could Have Prevented


Photo 1981 by J-E Nystrom, Helsinki, Finland/CC 3.0

It’s human nature to be complacent. We’re all lazy, right? But aviation isn’t an industry that welcomes complacency, and even the slightest oversight on behalf of a pilot in command can mean the difference between a successful flight and an unsuccessful one.

My flight students get tired of me reminding them about checklists. Before we even get into the airplane, I can often be heard saying: "That preflight checklist is there for a reason." And on downwind, every single time: "Before Landing Checklist." Some people understand the tedious nature of checklists and accept it; others defy it.

Why don’t pilots use checklists? Probably because they don’t expect anything bad to happen when they don’t. After all, they’ve skipped a checklist- er, many checklists - before and nothing bad happened. Maybe they remember all of the items, after all. Or maybe it’s true that 999 out of 1,000 times, a forgotten checklist item still results in a successful flight, which reinforces the pilot’s belief that it isn’t complacency, but skill, that gets him back on the ground safely. Unfortunately, this couldn’t be more wrong.

We’d all like to think that we’d never end up crashing because of a forgotten checklist item. But here are a few examples of average pilots who failed to accomplish checklist items or otherwise got into trouble for a checklist-related item. We’re not any different. We’re not immune. At the very least, it’s embarrassing to end up like one of these pilots; at the worst, fatal. If using a checklist can potentially prevent you from embarrassment or death, shouldn’t we just use it?

Here are four accidents where proper checklist use would probably have prevented the accident entirely:
Gear Down and Locked
As seen on YouTube, the pilot of this Piper Aerostar twin-engine airplane landed without gear at Aero Acres Air Park in Port St. Lucie, Florida. And then, to everyone’s surprise, he took off again. You can see from this video that the airplane is coming in too fast and unstable, and the pilot decides to go around only after touching down. Unfortunately, the pilot not only forgot the gear, but he forgot his go-around procedures. The pilot claims that he intended to go around, retracted the gear and all of the flaps prematurely and sank to the runway. Once airborne, the pilot is said to have flown the aircraft all the way back to his home in Ft. Lauderdale- about 100 miles.

This is only one report of many, many gear-up landing situations. Pilots: Don’t forget your GUMPS checklist!

Flight Controls Free & Correct

Earlier this month, the NTSB released an animation highlighting the crash of a Gulfstream IV in Bedford, Massachusetts last year. The aircraft skidded off the runway after a failed rejected takeoff, killing seven people on board - two pilots, a flight attendant and four passengers. The reason for the crash? Failure to check that the flight controls were free and correct before takeoff, and subsequently failing to expedite a rejected takeoff once they determined the problem.

The NTSB report states: "A review of the flight crew’s previous 175 flights revealed that the pilots had performed complete preflight control checks on only two of them. The flight crew’s habitual noncompliance with checklists was a contributing factor to the accident." Sadly, seven lives were lost because basic checklist procedures were not followed.

Water Contamination
There are several ASRS reports from pilots who have lived through off-airport landings due to engine failure. Many of these emergency situations are due to engine failure from fuel starvation. In many of those cases, water contamination was the culprit. In this ASRS report, a man describes his lackadaisical preflight habits after his Grumman Tiger engine quits due to water in the fuel tanks:

"Although I did not discover the water prior to takeoff, I have learned a valuable lesson. I feel that I had gotten complacent in my approach to the pre-flight in that I never found condensed water in my tanks before due to keeping them full at all times." He admits to failing to sump the fuel carefully to check for water.

Got ATIS?
In the early days of flight training, it might not be apparently obvious why a student’s flight instructor emphasizes the importance of getting a current altimeter setting. If the flight is conducted in VFR, the altimeter can be off by 100 feet and it might not matter much. It’s not until a pilot flies an approach to minimums that he realizes the value of setting the altimeter correctly. Being 100 feet lower than you intend when you’re descending on an approach can mean crashing into the runway or just short of it.

Knowing how an altimeter works and accounting for altimeter error will only keep you out of trouble if you set it correctly. We’ve all heard stories of pilots being to low or too high during an approach into IMC. This compilation of NASA ASRS reports tells how altimeter errors can lead to altitude deviations, traffic separation violations and landing accidents.

The NASA report states, for example, that, "A helicopter accident resulting in four fatalities was attributed at least in part to an incorrectly set altimeter during a period of known low barometric pressure. The report from the Canadian Aviation Safety Board states: ‘The helicopter was being used to transport personnel to work sites across a large frozen lake. An approaching low pressure area with snow and high winds...reduced visibility to near zero in some areas. The pilot most certainly encountered adverse conditions and altered course to circumvent the worst areas. The aircraft was later found...wreckage was widely scattered. The altimeter showed a setting on impact of 30.05; the correct setting would be about 29.22, causing the altimeter to read about 800-850 feet high. The altimeter had obviously been set two days previously [apparently during a time of high barometric pressure-Ed.].’"

Incorrect altimeter settings can be fatal. Checklist procedures should always include getting the current altimeter setting occasionally during flight and always before landing.

Mastering the Go-Around


Every pilot knows that a good landing always begins with a good approach. But how does a pilot know when an approach is unstable? And what happens when the approach is unstable, but the pilot thinks he can salvage it? We all preach that a go-around is the simplest way to prevent a landing accident, but when was the last time you performed a go-around? Are you confident that you’ll respond the right way after a long flight, when you just want to go home, when you’re low on fuel, or when you just botch the landing?

A stable approach is one in which the aircraft is on glide path, on the desired approach airspeed, and configured appropriately for landing at a descent rate that will allow for a normal transition to land. Sounds easy enough, right? So why do so many pilots continue an approach to a landing, even after all of the warning signs of an unstable approach? And why are there still so many loss-of-control accidents during the approach and go-around procedures?

The stable approach is so important that most commercial operators require a go-around in the event of an unstable approach. For most airlines and commercial operations, if the approach is not stabilized by a certain height above the ground (sometimes 1,000 feet and sometimes 500 feet, and sometimes there are requirements for each), the pilot must execute a go-around. Stable approaches are a big deal, and one that the professional aviation world does not want to tangle with. In general aviation, however, we often don’t have these standard operating procedures written out for us by a company. Most of the time, we’re on our own. If we’re IFR, we can and should use the FAA’s guidelines, which state we should "…depart the FAF configured for landing and on the proper approach speed, power setting, and flightpath before descending below the minimum, stabilized approach height; e.g., 1,000 feet above the airport elevation and at a rate of descent no greater than 1,000 feet per minute (fpm), unless specifically briefed." For light aircraft pilots, the FAA basically tells us to maintain a proper glidepath visually. But we should still note that an unstable approach means one that is too high, too fast, or not in a normal position to land (i.e., excessive maneuvering is needed to land) and if any of those conditions exist, we should execute an immediate go-around.

We all want to make the first landing work. We don’t want to go around, maybe because it wastes time, wasted fuel, or just because we have too much pride and want to be able to land in any condition. But perhaps part of the problem is that we just don’t practice go-arounds very often, and not often enough. We don’t get familiar with them. We’d rather sacrifice the aircraft, sometimes even our own life, to get the airplane on the ground rather than waste a few more minutes to try again, or risk a go-around, which seems like a hazardous maneuver to those who have not mastered it.

Going around isn’t always the best option, but most of the time it won’t hurt. And when it’s the better option, you should absolutely be ready to accomplish one.

Commonly a student or a certificated pilot doing a flight review will blow off the go-around as if it’s an easy maneuver not worth practicing. Be careful about this; I’ve found that many pilots will bust a check ride or flight review for bad go-around procedures. To simplify this maneuver, I teach the 5 Cs, which work well for many types of general aviation aircraft (but check your aircraft POH for proper procedures!)

  • C- CRAM:Full/climb power, props forward, carb heat off
  • C- CLIMBSet the Vx or Vy climb pitch attitude and CLIMB! So many of us get distracted during a go-around procedure and we fail to climb! And keep in mind that if you have the aircraft trimmed for a slow-airspeed descent, adding full power will cause the nose to pitch up. Be ready to add forward pressure on the controls to counteract this pitch-up moment and prevent an elevator trim tab stall.
  • C- CLEAN Retract gear and flaps as necessary. In some aircraft, you’ll want to retract the first 30-40 degrees of flaps right away. For many common training aircraft, you’ll wait until you get to a safe altitude and airspeed, after the climb has been established, and retract flaps in increments, stabilizing the aircraft in the climb each time. Many people get excited and want to retract the flaps either all at once or just too early in the game. Cram, climb, and thenclean it up.
  • C- COOLOpen the cowl flaps and lean the mixture, if necessary.
  • C- CALL You’ll probably need to make a radio call, whether it’s to notify other traffic in the pattern at a nontowered field, or to announce your missed approach with the towet or with approach, but radio communication should only come after flying the airplane to a safe altitude at a safe airspeed and navigating to where you need to go.

Often, I witness students or certificated pilots botch not just a landing, but the resulting go-around procedure, as well. Practice this maneuver to proficiency – a bad landing isn’t something worth salvaging, but you’ll need to keep flying the airplane and properly execute the go-around if you want to be successful the second time around.

The End of the PTS? What the New Airmen Certification Standards Will Mean for Pilots


In order to obtain a pilot certificate of any kind in the United States, a pilot must take an FAA Practical Test, better known as a checkride. The checkride you might take tomorrow is not much different from the checkride I took ten years ago. That is about to change. The FAA recently announced that the practical test standards that we all know so intimately will be overhauled. But will pilot training change? Will the actual checkride be conducted differently than it has for decades? Will aviation safety improve?

After the creation of the Air Commerce Act in 1926, which introduced new rules for pilot certification and the first ever regulations pertaining to aviation, along with a host of other things like new navigational aids and designated airways, the nation's first certificated pilots were born. The first official pilot license was issued to William P. MacCracken, Jr., after both Charles Lindbergh and Orville Wright declined the honor, with Orville boasting that he did not need a piece of paper to prove to the world that he was the first pilot.

This first pilot certificate was awarded as an honor in recognition of service to civil aviation. Subsequent certificates were awarded based on the personal judgment of examiners, which could be subjective. To standardize and make more objective the requirements for checkrides, the FAA eventually introduced the Practical Test Standards. These practical test standards outlined more specific expectations for pilot applicants and gave pilot examiners a rubric with which to evaluate pilot applicants. The test standards began mostly as a maneuvers-based evaluation, making sure the pilot could take off, land, recover from stalls, navigate by means of pilotage and dead reckoning, and others. Today, we still use these same practical test standards, although they've been modified over the years to include advanced navigation and new safety protocols. Yet, the practical test standards remain primarily maneuvers-based: The PTS lists what the applicant should be able to do, the conditions under which each task is to be performed and an acceptable performance standard for each maneuver or task.

The trouble, as accident data suggests, is that mastering a maneuver to a certain level, while it requires effective airspeed and altitude management, is not the most effective indicator of a safe pilot. The Nall report, for example, tells us year after year that improper decision-making and improper planning are common causes of accidents. The 2010 Nall report states that, "After excluding accidents due to mechanical failures or improper maintenance, accidents whose causes have not been determined, and the handful due to circumstances beyond the pilot’s control, all that remain are considered pilot-related. Most pilot-related accidents reflect specific failures of flight planning or decision-making or the characteristic hazards of high-risk phases of flight."

The PTS was created principally to provide objective standards for evaluating and certifying pilots. We have since learned that most of the qualities and abilities that separate safe from unsafe pilots are very difficult to quantify. In an effort to focus attention on these more subjective qualities – knowledge, discipline, risk assessment and management – the flight training community has in recent years created training techniques designed to incorporate these concepts. These techniques would include scenario-based training, FITS (FAA-Industry Training Standards), and training focused on technically advanced airplanes. Most thoughtful flight instructors already make every attempt to include risk management in the training regimen. The question remains as to how to evaluate these principles, which are really processes of thought, mental and emotional approaches to flight, in the course of a practical test. In recent years, these concepts have made their way into the existing PTS as front matter called "special emphasis areas," but only now, with the FAA's new Airmen Certification Standards (ACS), has there been a serious attempt to integrate these concepts into the specific objective tasks of the PTS.

But what exactly does this mean? Will it accomplish anything productive or valuable to flight training? The most prevalent change you'll see will be in the task list included. What we know currently as the PTS will be incorporated into the ACS, and the task list items, which were fairly brief, will be expanded to include many more specifics. For example, the current version of the Private Pilot PTS has 10 objectives listed for the Soft Field Approach and Landing task. It looks like this:

The new ACS project will have much more specific tasks in four different areas under the Soft Field Approach and Landing task: Objective, knowledge, skills and risk management. From a reading of the draft of the proposed ACS, this will be true for every task in the ACS. Knowledge and risk management are now made more specific by referring, in the standards for each task, to ways in which these somewhat amorphous and slippery concepts apply specifically to that task. It goes into much more detail about what could be evaluated on the check ride, including an entire section on risk items. It will look like this:

Along with the added emphasis on risk management, some students and instructors may be relieved to know that there will also be a change in the FAA's written knowledge tests. The FAA admits that over the years, parts of the knowledge test question bank have become redundant and outdated. With the new ACS, we should see the demise of old questions about NDBs and and irrelevant and poorly worded questions that include multiple calculations and interpolations. That's good news. As for when the new ACS will take effect, the FAA is proposing a rolling introduction beginning in late 2015 with the Private Pilot, the Commercial Pilot ACS and the Instrument Rating ACS and revision of the corresponding knowledge tests and codes. A Frequently Asked Questions document recently posted by the FAA admits that this schedule may slip into 2016, but advises that examiners, now called evaluators, may already use the draft ACS as guidance for the administration of checkrides.

The FAA wants us to look at the new ACS as an improved upon PTS, a long-overdue plan to make the qualities now known to correlate with safety an integral part of flight training and testing. They define it as "a holistic, integrated presentation of specific knowledge, skills, and risk management elements and performance metrics for each Area of Operation and Task." I'm not entirely convinced that this will be anything new or unusual for those of us training pilots. The performance standards will remain the same, and, according to the FAA, the ACS will not change the check ride. Instructors should already be teaching risk management and decision-making at every step of flight training, although the specific bullet points now included under each task may suggest specific ways in which these qualities pertain to every task we perform as pilots. In the end, the ACS is a change that is past due and should align the evaluation of pilots with the principles we should have long since been teaching.

Aviation's New Challenge: Software Glitches and Hackers?


Photo: FAA

The next generation of flying has arrived: From paperless boarding passes to paperless cockpits, we are moving to a completely computerized aviation future. It's almost like something out of a futuristic cartoon like The Jetsons with our tablet computers, internet-ready modernized passenger seats and synthetic vision glass cockpits.

Today's flights are planned on computers and sent to pilot's iPads, replacing the pounds of manuals, charts and checklists that pilots used to lug around. Outdated navigation systems are being replaced with a single, incredibly accurate, satellite based system called ADS-B. Inflight Wi-Fi service for passengers has not only become popular, but it's now almost expected from frequent airline travelers. And our nation's airspace system is getting a complete overhaul with NextGen, which includes programs like ERAM, Datacomm and many other communications systems.

This is all good news… until something crashes (or gets hacked). And we were recently reminded that sometimes computers do crash, when a few dozen American Airlines crews were left without proper charts after their iPads suddenly crashed on them while flying. The software glitch left dozens of flights and many passengers delayed.

Computers are clearly the efficient way to modernize aviation, and it's a welcome and inevitable progression toward a more effective airspace system. But there are a few things that haven't fully kept up with the fast-moving aviation industry, like software management and cyber security.

Are airplane computers secure?
Experts have warned that our industry's efforts to keep iPads, ADS-B and other onboard communication devices secure aren't comprehensive enough. An April 2015 GAO report evaluated the cyber security strength of the FAA's six major NextGen programs: Surveillance and Broadcast Services Subsystem (SBSS), Data Communications (Data Comm), NAS Voice Switch, Collaborative Air Traffic Management (CATM), Common Support Service-Weather (CSSWx), and System Wide Information Management (SWIM), which will all use an IP-based network to communicate with each other, as well as with thousands of aircraft flight deck technologies.

You can imagine that an entire system based on a computer network might be susceptible to hackers. Passengers are connected through in flight Wi-Fi. Pilots are sometimes connected to Wi-Fi via their company iPads, and will also be vulnerable to the hacking of onboard equipment through an IP network. And ATC is going to be on the ground, potentially connected to the same network. While the FAA has taken some measures to secure the networks, information in the GAO report demonstrates that the system is still susceptible to hackers.

"According to FAA and experts we interviewed, modern communications technologies, including IP connectivity, are increasingly used in aircraft systems, creating the possibility that unauthorized individuals might access and compromise aircraft avionics systems, " the GAO report states. In the past, on board systems have been insolated, but IP networking included in the many new NextGen technologies could leave not just one aircraft's systems vulnerable, but any other computer on the network.

How can operators avoid software glitches?
Besides choosing a reliable third-party developer and a company with a sound history in computer application design, there's not much an airline or an operator can do to avoid an occasional software glitch except to prepare for and expect the occasional software glitch. So far, the airlines have been lucky. American Airlines had a few delays, yes, but the problem was one that was easily fixed by handing paper charts to pilots or getting them to a place where they could re-boot, upload new charts and move on. At no time were they actually in any danger.

But what happens when a seemingly trivial software glitch isn't so trivial anymore? This is a question that was relevant yesterday, remains relevant today and will be relevant still in the future. Computers are already in use at most ATC facilities and in most aircraft. A software glitch in an aircraft is a problem, but not necessarily a dangerous one. Airplanes have backup navigation systems, backup electrical systems and backup instruments that are powered by something other than a computer.) A pilot can fly safely if their onboard computer crashes. It would test their skills, for sure, but that's what pilots train for.

A computer failure or software glitch at an ATC facility can cause major delays, possibly even for days. Remember that fire at the Chicago ARTCC facility? It not only knocked out both the primary and secondary communications networks, but it knocked out the whole region's ATC capabilities. Everyone survived, albeit painfully.

If we can glean anything from recent events, it's that in order for our industry to move forward in the world, we are going to have to rely on computers, and computers are not perfect. We have to do what's necessary to mitigate and control any associated risks, like those from hackers and software issues. And as we learn to protect our computer systems we'll likely have a few problems along the way similar to American Airline's software glitch, but the overall outcome will be an impressive, capable air traffic system that allows us to fly even more efficiently and safely than ever before.

What are your thoughts?

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