Pilot Proficiency Archives - FLYING Magazine https://cms.flyingmag.com/pilot-proficiency/ The world's most widely read aviation magazine Wed, 09 Oct 2024 14:18:50 +0000 en-US hourly 1 https://wordpress.org/?v=6.6.1 Hurricane-Hunting P-3 Experiences Severe Turbulence https://www.flyingmag.com/weather/hurricane-hunting-p3-experiences-severe-turbulence/ Wed, 09 Oct 2024 14:13:07 +0000 https://www.flyingmag.com/?p=219181&preview=1 Remarkable video from aboard a Lockheed Orion illustrates the intensity of Hurricane Milton.

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One of the National Oceanographic and Atmospheric Administration’s two “hurricane hunter” Lockheed WP-3D Orion aircraft flew into the eye of Hurricane Milton as it approached the Florida coast.

Video from on board the four-engine turboprop has been trending on the internet.

Members of the NOAA Commissioned Officer Corps struggled with severe turbulence aboard the Orion as scientists gathered data on wind speed, temperature, record-low pressure, and humidity.

As of Tuesday afternoon, the hurricane was downgraded to Category 4 status from Category 5.

Still, the 155 mph winds represent a significant threat to the west-central coastal area of Florida with storm surges of 10 feet or more expected upon landfall, which is expected Wednesday.


Editor’s Note: This article first appeared on AVweb.

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Corrosion 101: What Causes It? https://www.flyingmag.com/ask-flying/corrosion-101-what-causes-it/ Wed, 09 Oct 2024 13:22:42 +0000 https://www.flyingmag.com/?p=218931&preview=1 Here's the lowdown on this natural process affecting metals.

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There has always been plenty of chatter concerning OEM service documents, specifically whether compliance is optional or mandatory.

Are service documents mandatory? No. Are they a good idea to implement? It depends, but for the most part, yes, and you’ll soon discover why.

Corrosion comes in all shapes and sizes. It is a natural process in which metals deteriorate due to chemical reactions with environmental elements, such as oxygen, moisture, and pollutants. In aviation, corrosion can manifest in various forms, including surface, pitting, intergranular, and stress corrosion cracking.

Each type poses significant risks, potentially weakening the structural integrity of the aircraft and leading to safety hazards. We’ve recently seen how corrosion affects wing spars like with the Piper PA-28 and Cessna 177 and 210, for example. These started as Service Bulletins (SBs) to inspect for corrosion and escalated to mandatory compliance in the form of Airworthiness Directives (ADs).

The implications are severe. Corrosion can lead to structural failures, increased maintenance costs, and, in worst-case scenarios, catastrophic accidents. Once you have the basics and understand the theory, you are ready to progress to the next level.

That’s right, it’s aircraft maintenance time, and here’s one example.

Learjet 45

The Learjet is legendary among corporate aircraft—produced from 1964 to its unfortunate scuttling in 2021. Learjet became synonymous with business aircraft in the early days of private business travel.

“Learjet models are known for their exceptional performance, speed, and range,” said Sky Aircraft Maintenance. “Airframe issues can be a common maintenance concern for Learjet aircraft. Due to the high speeds and stresses placed on the airframe during flight, wear and tear can occur over time, leading to a need for structural repairs. This can include corrosion.”

On July 13, 2007, the Australian Civil Aviation Authority released AWB 57-004 Lear Jet Industries 45 Wing Corrosion. The agency said this correspondence was needed because “recent reports have been submitted indicating that corrosion has been found on the lower skin of both wings fitted to the Lear 45 aircraft. This corrosion resulted in the replacement of the entire lower-wing skins.”

Years later, in February 2019, Learjet, now owned by Bombardier, released a series of Service Bulletins addressing “wing spar inspection.” The reason? Corrosion had been observed on the lower-wing splice plates, requiring a more frequent interval to detect and correct protective coatings.

Remember our chat earlier about adhering to the manufacturer’s recommendations? 

Fast-forward a bit and the series of Learjet bulletins are now the FAA’s AD 2021-23-08.

What prompted this escalation? According to the AD, exfoliating corrosion was found on a particular Lear 45 upper surface of the lower center-wing, midspar splice plate during unrelated maintenance. The corrosion appeared to extend halfway through the thickness of the splice plate. Since the initial report, the FAA has received 23 additional accounts of corrosion from Learjet.

Jerel Bristol, owner of SEAL Aviation in Hollywood, Florida, was not surprised when the call came in. Bristol is aware of the trouble that Learjets have with wing-spar corrosion and knows the AD well. His team deploys to aircraft or ​AOG situations for mobile fuel leak repair, nondestructive testing, and structural repairs anywhere in the world.

During the center-wing inspection, a SEAL technician identified corrosion on the center-wing splice plate. I spoke with Bristol, and he said that it is a common area to find corrosion past repairable limits, which requires the replacement of the forward and aft splice plates.

After pulling the affected parts off the airframe, the SEAL team quickly repaired the area and replaced the damaged parts. The pictures reveal a sea of cleco fasteners. 

The guys buttoned up the Lear, and the owner was wheels-up again. 

The Cause

The big question remains: What causes corrosion?

One follower commented on a SEAL Aviation webpage post about the Lear 45 repair, stating that brine used for deicing could have contributed to the corrosion. He is not far off. Environmental elements can contribute to aircraft corrosion.

These factors include:

• Humidity and moisture, particularly in coastal regions.

• Temperature fluctuations which can cause condensation.

• Exposure to deicing fluids and other chemicals.

• Poor maintenance practices and infrequent inspections.

The environment is not the only player in the corrosion game. According to Aviation Devices and Electronic Components (Av-DEC) in its article “Causes of Corrosion,” industrial pollutants are equally harmful and can be difficult to protect against.

These include several contaminants such as:

• Ozone (exposure from high altitude, motors, and welding)

• Carbon compounds (exposure from combustion engine exhaust)

• Sulfur dioxide (exposure from engine exhaust, smokestacks, and acid rain)

Operators and GA aircraft owners alike are well advised to take heed when an SB shows up in the mailbox. A recommended inspection, especially when it can be coordinated with other scheduled or unscheduled maintenance, may help ultimately reduce the total cost of ownership and down time if/when an issue becomes an AD.

Perhaps the best reason to take a closer look is personal safety and peace of mind through identifying a problem before it manifests in something tragic.


This column first appeared in the September Issue 950 of the FLYING print edition.

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Hurricane Milton Triggers Florida Airport Closures https://www.flyingmag.com/weather/hurricane-milton-triggers-florida-airport-closures/ Tue, 08 Oct 2024 17:42:37 +0000 https://www.flyingmag.com/?p=219126&preview=1 The storm is expected to deliver 'devastating' winds and a 10-foot or greater storm surge, the National Weather Service said.

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Multiple airports in Florida are closing in preparation for Hurricane Milton, which is expected to make landfall on the west coast of the state by Wednesday evening. 

Tuesday morning, the storm was categorized as a Category 4 hurricane, with maximum sustained winds around 150 mph and hurricane-force winds extending up to 30 miles from its center.

“A large area of destructive storm surge, with highest inundations of 10 feet or greater, is expected along a portion of the west-central coast of the Florida Peninsula,” the National Weather Service said Tuesday, calling it “an extremely life-threatening situation.”

Tampa International Airport (KTPA) suspended all commercial and cargo operations as of 9 a.m. EST Tuesday. 

“The airport will remain closed to the public until it can assess any damage after the storm,” the airport said in a statement.

The airport’s parking garages were also closed, and officials said it could not be used as a shelter because it is located in the “A” mandatory zone and “will not be staffed to assist others with supplies or assistance, nor will emergency services be able to respond to calls or transport individuals to or from the airport.”

Airport staff have been scrambling to prepare the airfield to minimize the damage from the storm. The airport is managed by the Hillsborough County Aviation Authority, which is also closing Peter O. Knight (KTPF), Tampa Executive (KVDF), and Plant City (KPCM).

St. Pete-Clearwater International (KPIE) in Pinellas County is also located in a mandatory evacuation zone. The airport said it would close after the last flight departed Tuesday and would remain shuttered Wednesday and Thursday because of the storm.

Orlando International Airport (KMCO) said it will stop operations Wednesday at 8 a.m. EST, although, according to a press release from the Greater Orlando Aviation Authority (GOAA), the airport will remain open to emergency/aid and relief flights. The airport is not a shelter, and officials said commercial flights will resume when it is deemed safe to do so pending damage assessment and weather.

At Miami International Airport (KMIA), the largest and busiest airport in the Sunshine State, officials said they were “closely monitoring” the storm and encouraged travelers to check with the airlines to confirm flight status before venturing to the airport.

Sarasota Bradenton International Airport (KSRQ) said it would close at 4 p.m. Tuesday EST, however, many flights had already been canceled.  

The FAA’s full list of  current airport closures may be found here.

Milton is also impacting recreational flying. In Lakeland, Florida, the Flightoberfest festivities scheduled for Saturday on the Sun ’n Fun campus have been postponed, per a statement on the website.

“Our primary concern is the safety of our staff and guests,” event organizers said. The event has been rescheduled for November 16. 

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Are Surface Observations Based on Instantaneous Measurements? https://www.flyingmag.com/ask-flying/are-surface-observations-based-on-instantaneous-measurements/ Wed, 02 Oct 2024 18:25:21 +0000 https://www.flyingmag.com/?p=218830&preview=1 All observations, whether automated or taken by human observers, should be used with care.

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Are surface observations based on measurements that are done instantaneously? 

Answer: Whether in the form of a METAR or by the ground-to-air radio broadcasts, every pilot uses surface observations to make many routine operational decisions during any particular flight. As we listen to the broadcast prior to taxi, it provides us with an altimeter setting and will likely determine the runway we use for departure.

When approaching an airport under instrument flight rules (IFR), it will help us determine if we’ll be flying a visual approach or need to execute a standard instrument approach procedure. And when Mother Nature is at her worst, it will let us know when we should skip the airport altogether and fly to our alternate destination.

Surface observations are one of those data points that we often take for granted. The truth is that they play a monumental role in many of our most routine decisions. They are not just used by pilots, however, as they also provide air traffic controllers, dispatchers, and weather forecasters with a reasonable depiction of the weather conditions at an airport.

Even with something as ubiquitous as a surface observation, there are some nuances you should understand.

Pilots at all experience levels should be familiar with the two primary automated observing systems deployed at many airports throughout the United States. This includes the Automated Surface Observing System (ASOS) and the Automated Weather Observation System (AWOS). Both of these automated systems consist of a collection of electronic sensors that measure the environment and then process the data to create an observation once every minute.

Sampling the Atmosphere

While many high-impact airports throughout the U.S. still rely on a trained weather observer to construct the routine or special observation (SPECI), automated systems supply them with uniform and objective data for the observation.

However, automated systems measure only the weather that passes directly through the sensor array so it is not able to report what’s happening outside the airport’s runway complex or what is referred to as the airport’s vicinity. Weather observers can certainly augment the observation to add these details.

At airports without a trained observer, pilots must completely rely on the “raw” automated observation. This, however, isn’t as raw as you might think. In order to provide a representative observation, the automated hardware must continuously collect the sensor’s real-time data over a period of time. The automated system applies an algorithm to the collected data to extrapolate the weather to cover a wider area referred to as the terminal area.

When the weather is sampled over a specified period, it will tend to “smooth out” the conditions but also will account for the normal meteorological variations that we see in the weather. Each of the various weather elements shown in the table below identifies the required sample times for its algorithms and provides a summary of where the data are considered valid.

Parameter Processing Radius (Miles)Interval Validity (Minutes)
Sky Conditions303-5
Visibility102-3
Precipitation101-2
Freezing Rain152-3
Temp/ Dew Point55
Wind21-2
Pressure15

For example, 30 minutes of data provides a fairly reasonable description of sky conditions. This means that the system will detect and process all the clouds (if any) passing over the sensor in the past 30 minutes.

To account for the latest sky conditions, the result is biased by double weighting (counting twice) the last 10 minutes of data. Using the last 30 minutes of data in this way will allow the system to determine the cloud base height and sky coverage included in the surface observation and becomes a reasonable estimate of the sky conditions over a three to 5 sm radius around the location of the sensor (usually sited on the field). 

Surface observations will often dictate the best opportunity runway when approaching an airport. [Courtesy: Scott Dennstaedt]

Beware of Rapidly Changing Weather

Even though an ASOS creates a completely new observation every minute, automated systems must have adequate sensor samples to develop an accurate observation. Therefore, in rapidly changing conditions, pilots should expect that most of the weather elements from the automated observations to trend slightly behind the actual weather.

For example, if skies are clear and a sudden broken sky appears on the sensors, ASOS will take only two minutes to report a scattered deck of clouds even though a trained observer may report a broken sky cover. It will take nearly 10 minutes before the observation system will catch up and indicate a broken cloud layer. 

This may or may not trigger a SPECI (special observation) for an ASOS (most AWOSs cannot report a special observation). It depends on the height of the broken layer. In other words, a sudden broken ceiling at 600 feet has a significant operational impact and will generate a SPECI since the flight category changed from VFR to IFR. But it will take nearly 10 minutes before the SPECI is issued given the discussion above.  

Each minute an ASOS processes the most recent 10 minutes of visibility sensor data to obtain a representative value. Therefore, when visibility drops suddenly (in one minute) from 7 sm to 1 sm, the ASOS needs about four minutes before the 10-minute mean values reach the 3 statute mile criteria. This criterion forces SPECI to alert pilots to a significant change in visibility in this instance. A total of nine minutes will pass before the ASOS will report the 1 sm visibility.

On the other hand, when the visibility rapidly improves from 1 mile to 7 miles, the ASOS generates a SPECI four minutes after reaching the 1.5 sm threshold. In about 11 minutes, the ASOS will report 7 sm. The system is intentionally designed to raise surface visibility more slowly than to lower it.  This design provides a margin of safety and buffers rapid changes when the visibility is widely fluctuating over a short period.

Hourly and special observations are the only ones created by human observers. In contrast, ASOS relentlessly measures the weather and could inundate pilots with more frequent special observations than a human observer when the weather is changing rapidly.

Thus, the system is purposely throttled to only provide SPECIs at no more than a five-minute interval to limit the number of observations that can be transmitted during the hour. An even slower response is seen at controlled airports where only the hourly and special observations must be prepared and broadcast on the Airport Terminal Information System (ATIS). At uncontrolled airports pilots can also receive the one-minute weather by calling the voice phone link or by the ground-to-air radio broadcasts. 

The FAA has created a Google map presentation online showing the locations of all automated weather systems across the country, which may be found here. This includes the frequency and phone numbers for each ASOS and AWOS currently in operation.  

Lockout Period

If you pay attention to the issuance time on METARs, you will notice that many are issued a few minutes before the top of each hour. This allows the observation to be transmitted and ingested into other computer systems such as numerical weather prediction models.

Some models get executed at the top of the hour or shortly thereafter. Starting at 47:20 past the hour, the ASOS begins to make its routine observation. By 53:20, the hourly observation has been prepared and edited and should be ready for transmission.

This period of time between 47:20 and 53:20 minutes after the hour is known as the lockout period. During this time, the ASOS is prevented from issuing any other reports, including SPECIs. The ASOS still continuously monitors and records the weather during the lockout period.

However, it just can’t issue a formal surface observation. This does not affect the one-minute weather you receive by calling the voice phone link or by the ground-to-air radio broadcasts, but it will affect any formal observations that are transmitted that you may see on your datalink weather broadcast.  

Can I Trust Automated Observations?

All observations, whether automated or taken by human observers, should be used with care.

Pilots must be aware of how long ago the observation was taken, under what conditions, and whether or not they are special observations. Even though automated systems are totally objective and maintain a certain uniformity among all sites, it does not mean they match what a pilot sees out the windscreen.

ASOS may occasionally report cloud decks lower than what is actually encountered. Sometimes precipitation, lower cloud fragments, or fog triggers these lower values. Pilots have said that these “lower” reported values often indicated the height below which they had to fly before gaining enough forward visibility to see an airport and land.

The key lesson here is to evaluate all reports closely before dismissing them as inaccurate.

Even though the visibility sensor is designed to objectively represent the visibility of the atmosphere over a wide range of weather conditions, day or night, it occasionally reports a visibility more optimistic than what a human perceives.

During the day, the human eye can be overwhelmed by bright light reflected in clouds, light precipitation, fog, or haze. Many pilots will resort to wearing sunglasses to obtain some relief from the glare.

The ASOS visibility sensor is not as sensitive to this condition and sometimes reports a visibility approximately twice as high as what an individual may determine. Be alert for these bright conditions and expect a more optimistic value from the automated system.

Sometimes you really don’t need official weather observations when Mother Nature is on her worst behavior. If you squint hard enough, you may be able to see a private jet taxiing to depart given a visibility less than a quarter sm. [Courtesy: Scott Dennstaedt]

What Will Automation Not Provide?

We can easily become complacent when it comes to automation. We learn to trust automation and sometimes don’t acknowledge that it has real limitations.

 Therefore, to finish this discussion, it is just as important to know what automation will not provide.

Automation systems can only report the weather that passes through the sensor array. They do not provide a horizon-to-horizon evaluation of the weather. This means that weather in the vicinity of the airport will not be measured. A rain shower that passes just to north of the airport, for instance, may reduce visibility in that immediate area but will not be reported by the automated system.

Next, the ASOS only reports clouds that are below 12,000 feet. This means that an overcast cloud deck at 14,000 feet will be reported as clear. Effectively, a clear sky report from an automated station means clear below 12,000 feet.

For airports with a human observer, this report can be augmented to include clouds above 12,000 feet. Some of the new AWOSs being installed can automatically report clouds above 12,000 feet up to and including 30,000 feet.  

This shower in the airport’s vicinity will not be captured by an automated system. However, if the airport has a trained observer, the observation may be augmented to include VCSH. [Courtesy: Chris Bowman]

Automated systems can only report one precipitation type at a time. For instance, if freezing rain and snow are detected, snow is reported. Certainly, weather observers can edit the observation before transmission to include additional precipitation types. 

Lastly, the ASOS is not designed to report virga, tornadoes, funnel clouds, ice crystals, snow pellets, ice pellets, drizzle, freezing drizzle, and blowing obstructions such as dust or sand. All of these elements can be provided at locations that employ a trained observer. Often with drizzle, freezing drizzle, ice pellets, or a mixture, you will see the automated system report an unknown precipitation type (UP). 

Nevertheless, automated reporting is in its infancy, so it’s likely new sensors will be added to measure some of these other weather elements in the future.

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What Is the Lone Lug Meant for on This Cessna 172? https://www.flyingmag.com/ask-flying/why-is-there-only-one-lug-on-cessna-172-wheels/ Wed, 25 Sep 2024 14:23:11 +0000 https://www.flyingmag.com/?p=218360&preview=1 Seeing this on the ramp begs the question: Is it supposed to look like that?

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QUESTION: I just noticed something odd about an airplane on the ramp. The right wheel of the Cessna 172 has what looks like a lug nut sticking out of it, and this lug nut is missing from the left wheel. Is there supposed to be another part there? What is the lug for? Is the aircraft still airworthy?

Answer: For this one we reached out to our cadre of A&P and A&P/IAs. They tell us that the part was probably used to attach wheel pants once upon a time.

There may have been a lug nut on the other wheel that was taken off, or fell off. Wheel pants are not required on Cessna 172 under FAR 91.205, so this is not a grounding issue.

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Know Your Convective Outflow Boundaries https://www.flyingmag.com/weather/know-your-convective-outflow-boundaries/ Thu, 19 Sep 2024 16:50:16 +0000 https://www.flyingmag.com/?p=217975&preview=1 Pay particular attention to those strong, gusty winds before attempting a landing at an airport when storms are approaching.

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Surface analysis charts are issued every three hours by meteorologists at the Weather Prediction Center (WPC). On some you may have seen a tan dashed line with a label “OUTFLOW BNDRY” nearby. This is what meteorologists call a convective outflow boundary. 

Convective outflow boundaries emanating away from thunderstorms are generated as cold, dense air descends in downdrafts then moving outward away from the convection to produce a mesoscale cold front also known as a gust front. Some gust fronts can be completely harmless or may be a precursor for an encounter with severe turbulence and dangerous low-level convective wind shear. The direction of movement of the gust front isn’t always coincident with the general motion of the thunderstorms. If the gust front is moving in advance of the convection, it should be strictly avoided. The pilot’s best defense is to recognize and characterize the gust front using METARs, ground-based radar and visible satellite imagery.

According to research meteorologist and thunderstorm expert, Dr. Charles Doswell, “cold, stable air is the ‘exhaust’ of deep, moist convection descending in downdrafts and then spreading outward like pancake batter poured on a griddle.” As a pulse-type thunderstorm reaches a point where its updraft can no longer support the load of precipitation that has accumulated inside, the precipitation load collapses down through the original updraft area. Evaporation of some of the rain cools the downdraft, making it even more dense compared to the surrounding air. When the downdraft reaches the ground, it is deflected laterally and spreads out almost uniformly in all directions producing a gust front. 

Gust fronts are normally seen moving away from weakening thunderstorm cores. Once a gust front forms and moves away from the convection the boundary may be detected on the NWS WSR-88D NEXRAD Doppler radar as a bow-shaped line of low reflectivity returns usually 20 dBZ or less. Outflow boundaries are low level events and do not necessarily produce precipitation. Instead, the radar is detecting the density discontinuity of the boundary itself along with any dust, insects and other debris that may be carried along with the strong winds within the outflow. The gust front in southwest Missouri shows up very well on the NWS radar image out of Springfield as shown below. 

Crescent-shaped convective outflow boundary as detected on NEXRAD Doppler weather radar. [Courtesy: UCAR]

 An important observation is to note the motion of the gust front relative to the motion of the convection. In this particular case, the boundary is steadily moving south while the thunderstorm cells that produced the gust front are moving to the east. This kind of outflow boundary is usually benign especially as it gains distance from the source convection. On the other hand, a gust front that is moving in the same general direction in advance of the convection is of the most concern. These gust fronts often contain severe or extreme turbulence, strong and gusty straight line winds and low-level convective wind shear. 

As mentioned previously, gust fronts are strictly low-level events. As such, even the lowest elevation angle of the radar may overshoot the boundary if it is not close to the radar site. Shown above at 22Z, the NWS WSR-88D NEXRAD Doppler radar out of Greenville-Spartanburg, South Carolina is the closest radar site and clearly “sees” the gust front (right image). However, the NEXRAD Doppler radar out of Columbia, South Carolina (left image), is further away and misses the gust front completely. As the gust front moves away from the radar site, it may appear to dissipate, when in fact, the lowest elevation beam of the radar is simply overshooting the boundary. 

As a result, it is important to examine the NEXRAD radar mosaic image before looking at the individual radar sites.

Not all gust fronts are easy to distinguish on visible satellite imagery; the gust front could be embedded in other dense clouds or a high cirrus deck may obscure it. It is also possible that the boundary may not have enough lift or moisture to produce clouds. In many cases, however, it will clearly stand out on the visible satellite image. When the gust front contains enough moisture, as it was in this situation, cumuliform clouds may form along the boundary and move outward. This is very common in the Southeast and coastal regions along the Gulf of Mexico given the higher moisture content.  

As this particular gust front passed through my neighborhood located south of Charlotte, North Carolina, strong, gusty northerly winds persisted for about 10 minutes. As is common, the main core of the precipitation didn’t start to fall for another 10 minutes. When a gust front such as this appears on satellite or radar, it is important to monitor the METARs and ASOS or AWOS closely for the occurrence of high winds. Several airports in the vicinity reported wind gusts peaking at 30 knots. The sky cover went from being just few to scattered clouds to a broken sky with these cumuliform clouds moving rapidly through the region.

As mentioned earlier, a gust front moving away from thunderstorms is a low-level event that can contain very strong updrafts and downdrafts. The graph shown above is a time series, plotting the upward and downward motion or vertical velocity in a strong gust front as it moved over a particular point on the ground. The top half of the graph is upward motion and the bottom half is downward motion. 

Time increases from left to right. As the gust front approaches, the vertical velocity of the air upward increases quickly over a one or two minute period. While the maximum vertical velocities vary with height in the outflow, a common maximum number seen is 10 m/s at about 1.4 km or 4,500 feet agl (25 knots is roughly 12 m/s for reference). As the gust front moves through, the velocities abruptly switch from an upward to a downward motion creating strong wind gusts at the surface. Most outflow boundaries don’t extend above about 2 km or 6,500 feet agl. What is remarkable is that upward to downward motion changes in just about 30 seconds over the ground point where this was observed. But imagine flying an aircraft at 150 knots through this; the up and down exchange will happen in just a few seconds producing a jarring turbulence event.

Just in case you were wondering, gust fronts are conveniently filtered out by your datalink weather broadcasts as shown above for XM-delivered satellite weather. This is because the broadcast only provides returns from actual areas of precipitation. Often outflow boundaries or gust fronts produce low reflectivity returns that fall below the threshold used to filter out other clutter not associated with actual areas of precipitation. When in flight, pay particular attention to surface observations looking for strong, gusty winds before attempting a landing at an airport when storms are approaching. 


This feature first appeared in the July/August Issue 949 of the FLYING print edition.

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Why Are Some Military Airplanes Gold? https://www.flyingmag.com/ask-flying/why-are-some-military-airplanes-gold/ Wed, 18 Sep 2024 15:09:55 +0000 https://www.flyingmag.com/?p=217900&preview=1 Here's why several biplanes used in World War II had gold wings.

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Question: Why do so many biplanes used in World War II have gold wings? I thought the whole idea of military paint jobs is for them to be camouflaged, and the gold sticks out.

Answer: The biplanes you mention—Stearmans, Kaydets, and Navy SNJs—were mostly likey trainers.

They were yellow because if they went down on a training mission—as they often did—they were easier to spot from the air.

Often the trainees made unscheduled off-airport landings in hayfields, swamps, forests, and the desert. Having an aircraft painted to look like terrain would have made it more difficult to find them.

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The One-Time Water Landing https://www.flyingmag.com/pilot-proficiency/the-one-time-water-landing/ Fri, 13 Sep 2024 13:10:09 +0000 https://www.flyingmag.com/?p=217461&preview=1 You can't practice ditching a wheeled aircraft, so you must get it right.

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On January 15, 2009, approximately two minutes after takeoff from LaGuardia Airport (KGLA) in New York, US Airways Flight 1549 encountered a flock of birds. Several were ingested into the two engines, resulting in a nearly complete loss of thrust.

Out of power, altitude and options, Captain Chesley “Sully” Sullenberger and copilot Jeffrey Skiles ditched the aircraft in the Hudson River near midtown Manhattan. There were 155 souls on board. There were injuries but no loss of life, and the term “Miracle on the Hudson” was coined since it was viewed as one of the most successful ditchings ever performed.

What Is Ditching?

According to the Aeronautical Information Manual (AIM), ditching is defined as “a controlled emergency landing of an aircraft on water.” If the aircraft isn’t equipped with floats, it’s usually a one-time-only event, and unlike power-off landings to full stop on a runway, it is not something you can practice. But you can prepare mentally by studying what to do in the unlikely event of a water landing.

Any time you fly over water, you should be thinking about it, especially when the aircraft is beyond gliding distance of the shoreline.

Always Consider It When Flying Over Water

“Do you know how to swim?”

A pilot of the J-3 Cub asked me this the first time I took off from Runway 17 at the Tacoma Narrows Airport (KTIW) in Washington. The airport sits on a peninsula that leads onto the Puget Sound. If you have seen the 1983 movie War Games, the scene with the ferryboat and the island was shot just south of KTIW.

The pilot asked the question after I wondered out loud where we’d land if we had an engine issue. I assured him I could swim as in my teens I trained to be a lifeguard and was thrown out of boats in the middle of a lake fully clothed, with no life vest to test my skills. Until that flight all my training had been over land.

Most of my information about ditching comes from interviewing colleagues who have done it.

In July 2022, John La Porta, a CFI in the Seattle area experienced an uncommanded loss of engine power while flying a Cessna 150 over the water west of Seattle. La Porta was alone in the aircraft at the time. According to La Porta, the aircraft was at less than 2,000 feet when he noticed a loss of oil pressure. He was attempting to reach King County International Airport-Boeing Field (KBFI), but when the engine lost power, he knew he wouldn’t make it. He didn’t want to take a chance on flying over the hilly terrain, homes, and streets, so he set up to put the aircraft in the water next to Alki Beach.

Things happened quickly, he recalled. He tightened the lap belt and cinched the shoulder harness as tightly as he could. He did not lower the flaps to 40 degrees per the ditching instructions in the POH, but that may have been a blessing as the flaps would have possibly blocked his egress from the aircraft, which flipped over. He was upside down but couldn’t tell in the submerged aircraft.

Although the shoulder harness probably saved his life since it kept him from slamming into the panel, it also pinned him inside the airplane.

“I could not get the belts to release until the airplane’s tail settled into the water. I had one hand on the window, and I was able to sort of stretch up and take a breath of air, and then I found the lap belt and was able to get it undone. I held on to the window as I released the shoulder harness, and then I swam out of the window,” La Porta told FLYING, adding that, if he had someone else in the airplane, he’s not sure if they both would have survived because of the seat belt jamming.

After that experience, La Porta became a big believer in carrying a seatbelt cutter on his person.

Training for the Worst

When it’s more than just you in the airplane, ditching reaches a whole new level, said Amy Laboda, an ATP/CFI and FLYING contributor.

On June 14, 2001, Laboda was in her Cessna 210 with her two daughters, ages 9 and 10, their 15-year-old babysitter, and an adult family friend heading for the Cayman Islands. Shortly after takeoff from Key West International Airport (KEYW) in Florida, as the aircraft passed through 1,500 feet, there was a loud bang and a loss of engine power.

“It was the kind of sound that makes you push the nose over and start turning back,” said Laboda, adding that she drew upon her experience as a glider pilot to get the most distance out of the altitude available but quickly realized she wasn’t going to be able to make it back to land.

She declared an emergency and was cleared to any runway but had to respond, “Unable.”

“The last thing I heard from ATC was ‘services on the way,’” she said.

The aircraft came in like a bobsled, and the windscreen popped out. “It was like getting hit in the face with a fire hose,” said Laboda, noting they were lucky because the water was flat, warm, and smooth.

Laboda boasts years of experience teaching the ditching seminars for the FAA FAASTeam, and from an early age she taught her kids how to quickly put on the overwater safety gear.

“When they were little, we made a game of it,” she explained, adding that part of the preflight briefing is what to do if they had to put it down in the water.

Everyone did what they had been told to do and survived with just cuts and bruises. “There were several boats in the area, and we were in the water for less than 10 minutes,” she said.

Train to Ditch

If you have the opportunity to take a water survival course for aviators, do so. If not, chapter 6 of the AIM provides illustrations and textual descriptions of how to ditch an aircraft. There are a great many variables that result in a successful ditching.

The condition of the landing area is key. Is the aircraft coming down in rough seas or a calm lake? Does the pilot have the skill to come in at the slowest possible airspeed? Was there time to prepare?
The AIM advises stowing or jettisoning loose objects from the cockpit so they don’t become projectiles. Tighten seat belts and unlatch doors because if the aircraft frame is bent, they might jam. If you have time, jam a shoe in the door crack to prop it open.

The National Search and Rescue Manual along with the emergency section of most POHs advise pilots to attempt to bring the aircraft in at a slightly tail-low attitude—slower, the better.

Once the airplane comes to a complete stop, keep your seat belt on and reach for the door. When you have found the door and opened it, release the seat belt. It is important to stay belted until you have grasped the door handle because it helps with orientation. It’s dark underwater, and if the airplane is upside down, you won’t know it. Use the seat belt cutter if you have to—but still hang on to the door.

Once you are free of the belt, pull yourself clear of the aircraft and activate the life vest if you are wearing one. If you are underwater, blow one bubble and follow it to the surface.

Unlacing your shoes so you can kick them off easily is also a good idea because of all the articles of clothing you are likely wearing they are the heaviest and will drag you down.


This feature first appeared in the July/August Issue 949 of the FLYING print edition.

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NTSB Issues Deicing Safety Alert https://www.flyingmag.com/weather/ntsb-issues-deicing-safety-alert/ Thu, 12 Sep 2024 20:21:22 +0000 https://www.flyingmag.com/?p=217642&preview=1 The directive also warns that ice buildup on pitot tubes can lead to instrument failure, impacting readings for airspeed, altitude, and vertical speed.

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As winter approaches, the National Transportation Safety Board (NTSB) has issued Safety Alert SA-097, reminding pilots about the dangers of flying in icing conditions—namely the adverse effects of airframe and propeller icing on aircraft performance.

SA-097 emphasized that “as little as 1/4-inch of wing-leading edge ice accumulation can increase the stall speed by 25 to 40 knots and cause sudden departure from controlled flight.”

The alert also warned that ice buildup on pitot tubes can lead to instrument failure, impacting readings for airspeed, altitude, and vertical speed.

The NTSB acknowledged that some pilots have been taught to wait for a certain amount of ice to accumulate on the leading edges before using deice boots due to concerns about ice bridging. However, the FAA’s recent tests show that modern deicing boots, from aircraft manufactured after 1960, are not prone to ice bridging.

The agency warned that performance issues may arise if deice boots are not engaged promptly when icing begins and advises pilots to refer to their operating handbooks for specific procedures on boot activation and use.

The alert also cited several accidents where failure to follow operating handbook instructions led to in-flight loss of control, underscoring the critical importance of adhering to recommended deicing practices.


Editor’s Note: This article first appeared on AVweb.

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Why Aren’t Cessna 140s/150s Considered Light Sport Aircraft? https://www.flyingmag.com/why-arent-cessna-140s-150s-considered-light-sport-aircraft/ Wed, 11 Sep 2024 13:30:00 +0000 https://www.flyingmag.com/?p=217148&preview=1 It seems some pilots can’t wait for the change in weight requirement.

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Question: I understand MOSAIC (Modernization of Special Airworthiness Certification) is in the works and it will increase the weight limit on light sport aircraft (LSA) from 1,320 pounds to 3,600 pounds. That makes some of us wonder why the Cessna 140 and Cessna 150 can’t be flown as LSA right now. They are both two-place and have a stall speed of less than 51 mph. Wouldn’t it be possible to fly them at 1,320 pounds to make them legal to fly as LSAs as the rule stands?

Answer: The LSA rule as it stands limits aircraft to a gross weight of 1,320 pounds for land aircraft.

Gross weight is determined when the aircraft is certificated. The Cessna 140 GW is 1,450 pounds, and the Cessna 150 is between 1,500 and 1,600 pounds, depending on the year of manufacture. You can take the other seat out and fly partial fuel, and that will make the aircraft lighter, but it won’t change the certificated gross weight.

Understand that the LSA rule is under review with MOSAIC, and if approved as written, will increase the gross weight of aircraft to 3,600 pounds.

When that transpires, many of the single-engine light trainers flown today in the utility and normal category will likely become LSA compliant.

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