An Educational Runup

ByHank Gibson

When a pilot thinks of an engine runup in a single engine piston airplane, typically it is let’s find out if the engine is running rough or not, meaning a spark plug is fouled.  Believe it or not, there is a little more to learn from a runup than just checking the spark plugs.

A distinct advantage to having an engine monitor that monitors all EGTs and CHTs is you get a better idea of engine health.  When switching to one magneto or the other during the runup, all the EGTs should rise, showing that the temperature of the exhaust gas is going up from each cylinder.  This occurs because when running on only one magneto and one set of spark plugs in each cylinder, the mixture takes longer to burn, so, when the exhaust valve in the cylinder opens, the burn is still on going and this hits the EGT probe, causing a temperature rise.  An indication of a magneto failure in flight would be a rise in all the cylinders EGT without a change in mixture setting.

Now that we know what to look for when checking each magneto, what would one look for to show that there is a problem?  The basic that each student pilot is taught still applies.  The engine manufacturer puts a limit on RPM drop during the runup.  When checking one magneto or the other, watch for an excessive RPM drop.  If the RPM drops past the limit, this usually will be accompanied by engine roughness.

Why is that?  Let’s look at the cause for the excessive RPM drop.  For this, we need to go back to our EGT indicators.  Let’s say we have a 6 cylinder engine.  When the key is turned to the right magneto, the RPM drops 250 RPM and the engine gets very rough.  Look at the EGT gauge.  The cylinders where the spark plugs are firing normally will all show a temperature.  The cylinder (or cylinders) where there is no combustion, meaning a bad plug, will show no temperature.  This is because the mixture is just sitting in the cylinder and not igniting, therefore, no exhaust gases will be pushed out so there will be no EGT indication for that cylinder.  This is also how you tell a mechanic which cylinder to check for the bad plug.

It could also be a bad magneto.  If multiple cylinders EGT all drop, or the engine wants to quit entirely, you have a bad magneto or bad ignition harness.

What else can you learn during the runup?  Electrical system health is key, especially in all electric airplanes (meaning no vacuum system).  It’s a very good idea to turn on all the lights and pitot heat to ensure that a rise is indicated on the ammeter.  This means the alternator is carrying the load and working properly.

The next time you do your runup, keep an eye on your EGT to see the rise during a magneto check.

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  • Maintaining TKS Panels

    ByHank Gibson

    Columbia TKS Panels

    When cleaning airplanes, the majority of people don’t know how to properly maintain their TKS panels.  TKS panels provide wing leading edge, horizontal stabilizer leading edge, and, in the case of FIKI airplanes, vertical stabilizer leading edge de-icing protection.  For those not familiar with them, they are metal strips that have thousands of holes drilled into them where the TKS fluid seeps out. They have become quite prevalent on Cirrus aircraft, the Cessna TTx, and Mooney aircraft manufactured in the last decade or so.  The system is also known as a weeping wing system.

    Being on the leading edges, these panels pick up bugs very easily.  For the uninitiated, it would make sense to just use normal airplane cleaner to spray the panels and scrub the bugs.  Don’t!

    Using anything that contains Methyl Ethyl Ketone (MEK) as that can harm the TKS bladders behind the panels.  Any aircraft cleaner containing wax could cause the pores to clog, preventing the TKS fluid from properly seeping onto the wing.

    What’s the best thing to do?  Soap and water with a soft cloth is a good start (again, make sure it doesn’t have wax in it.  Dish soap would be suitable).  No hose available?  Just simply turn the TKS system on, let it run till you start to see fluid drip off the wings onto the ground, and use the fluid to clean the panels.

    A soft cloth would work fine, but, if the panels are really buggy, take a green scouring pad to do some scrubbing.  Just make sure the scrubbing motion is up and down with the grain, not side to side.  You can find the green scouring sponges on the dishwashing aisle in the grocery store.  Just leave one in the hangar for when you need it.

  • Air Traffic Control Privatization

    ByHank Gibson

    There was a bill introduced in Congress recently to take control of Air Traffic Control away from the FAA and give it to a private, for profit, corporation.  The initial reaction of pilots is “Ahhh!  User fees!” which we are all adamantly opposed to.  There are a myriad of reasons why this is a bad idea (the “Flying” article makes a comparison to giving NASA to Richard Branson and Jeff Bezos) and we as pilots should be against it.

    Read the “Flying” Magazine full article here.

    Air Traffic Control

  • GAMI Gains STC for G100UL, Unleaded Avgas

    ByHank Gibson

    For years, there has been clamoring for airplanes to get rid of lead in piston engine Avgas. In the early 2000s, Thielert created a Jet A burning piston engine for Diamond Aircraft that gained some traction, but Thielert had internal issues and ended up declaring bankruptcy. Several other Jet A piston engines have come down the line since then to some success (Diamond is currently using 2 Austro manufactured Jet A piston engines on it’s DA62 and a Continental manufactured Jet piston on the new DA50).

    The problem with a Jet A burning piston engine, though, is that those engines would be very expensive to put on existing airplanes, not to mention the cost of the STC alone.

    Insert GAMI (General Aviation Modifications, Inc.), the famed Ada, Oklahoma company that championed turbo normalization, balanced injectors, and lean of peak operations. For those that have been to GAMI’s engine class, you know that these guys are at the very top of their game in engine knowledge.

    In 2010, GAMI started the process of creating an Unleaded form of Avgas, terming it G100UL (the irony of traditional Avgas, 100LL, is the LL starts for low lead, but the lead levels in 100LL are actually quite high. UL stands for UnLeaded). Just before Osh Kosh in 2021, GAMI revealed that it’s work has come to fruition, gaining an STC for G100UL for Lycoming powered Cessna 172s.

    The amazing thing about GAMI’s product is that it is able to mix with 100LL and not cause any issues. This means fuel trucks, fuel lines, fuel pumps, and aircraft fuel tanks don’t have to have any modifications to them to use G100UL. Plus, pilots will see longer engine life using G100UL because of the simple elimination of the lead. In tests, combustion chambers in cylinders burned cleaner, so theoretically, cylinders and engines will last a lot longer.

    According to the company, GAMI has a few more tests to run and, assuming those go well, G100UL will be available for a whole lot more airplanes. An STC will still be required for the use of G100UL in a specific airplane, but the hope is, eventually, 100LL will be completely replaced by G100UL. The only downside is that G100UL is expected to cost about $1/gallon more than 100LL.

    GAMI has partnered with Avfuel, so expect to see 100UL showing up at all Avfuel FBOs in the next year or two.

    To read more, check out the press release on AOPA’s website.

  • Garmin Smart Glide

    ByHank Gibson

    Recently, I was training a customer who had a brand new instrument panel installed in his TBM 700. The avionics shop that did the work (Abilene Aero, who I highly recommend for any panel installs, located at KABI) told us when we picked the plane up that the new Garmin GTN 750Xi had the most recent software update, which included the Garmin Smart Glide.

    I had never used the Garmin Smart Glide before, so I was eager to check it out during our training. When we got to engine failures, we pushed the Emergency button on the Home page of the GTN 750Xi, and then the magic happened.

    The plane was also equipped with a Garmin G600TXi PFD and the Garmin GFC 600 Autopilot. In order for Smart Glide to work, there has to be either a GTN 750Xi or GTN 650Xi installed, along with a G500TXi or G600TXi and a Garmin Autopilot. Garmin is working on getting the legacy G500 as well as the GI 275 and G5 to work with the above GPS units for Smart Glide as well.

    Here’s what happens. The plane loses it’s engine. The pilot’s workload and stress level suddenly goes way up. Trim the airplane for best glide, find the nearest airport, attempt restart. Do it quickly so you have time to focus on the glide. Oh yeah, squawk 7700 and declare your emergency. All the while plummeting toward the ground in a somewhat controlled crash. Yikes.

    Garmin Smart Glide takes over the flying part, allowing the pilot to handle the restart, while making it much easier to squawk, talk and plan the engine out landing. On the home page of the GTN 750Xi/650Xi, the pilot simply taps the Emergency icon on the bottom of the screen. The Autopilot comes on and goes into IAS mode and maintains best glide while descending. The GPS immediately analyzes the Glide Advisor, and turns to the nearest airport in the glide ring (if there is no airport within gliding distance, the GTN 750Xi advises the pilot). Then, the Autopilot flies directly to the Nearest airport, allowing the pilot the ability to take attempt a restart.

    Once it is determined that the engine won’t start, the Garmin Smart Glide has excellent situation awareness tools. On all screens, the pilot is constantly being advised of how high AGL the plane is currently, while advising also of how high AGL the plane will be over the airport that the glide is set up for. There is also a short cut on the screen to tap to squawk 7700 as well as runway length information at the airport.

    The Garmin Smart Glide Button wasn’t installed yet in the TBM, but that will make things even easier when it is (it will be certified in January). This is amazing technology that all Garmin GTN 750Xi pilots should have their software updated to. Remember, you have to have a Garmin Autopilot and a Garmin PFD for it all to work.

  • Determining Pattern Altitude

    ByHank Gibson

    Figuring out the pattern altitude at an airport should be pretty simple, right?  But, in this day of helpful technology, most pilots actually get it wrong.  How can you always get it right?  Well, it just takes about an extra 15 seconds.  Here’s how.

    Traffic Pattern
    John Wayne Airport Traffic Patterns

    As outlined in the Aeronautical Information Manual, section 4-3-3, “traffic pattern altitudes for propeller-driven aircraft generally extend from 600 feet to as high as 1,500 feet above the ground.”  Further, in the Pilot’s Handbook of Aeronautical Knowledge on page 13-10, it states:  “1,000 AGL is recommended pattern altitude unless established otherwise.”

    Okay, so for piston driver’s, we’ve got it narrowed down to 1,000 AGL (Above Ground Level for those who don’t like acronyms).  But wait!  There’s that very important phrase at the end of the last quote:  “unless established otherwise.”  That means not all airports have traffic pattern altitudes of 1,000 AGL, or else they wouldn’t put that line in there!

    How do you find out what the TPA (Traffic Pattern Altitude) is for a certain airport if it’s not 1,000 AGL?  Great question!  Your first guess is probably to look on Foreflight.  Though this is a good start, it is not the full answer.

    Let’s use an example.  Look up KAQO, the Llano Airport on Foreflight.  At the top of the page, the airport elevation is stated as 1,101′ MSL and the pattern altitude is stated as 1,902′ MSL.  From what we just learned, 1,902′ MSL is not 1,000 AGL, so is 1,902′ MSL otherwise established?

    On the Airports page with KAQO pulled up, tap the A/FD tab, second to last on the left.  Scroll down to Llano Muni.  Read the whole entry.  Does it state in the entry that pattern altitude is different than 1,000 AGL?  It sure doesn’t.  So, because it is not otherwise established, pattern altitude at KAQO is 2,102′ MSL not 1,902′ MSL.

    Where did Foreflight get that?  I have no idea.  Too often, though, pilots look at the Foreflight pattern altitude and don’t actually check the Airport Facilities Directory (A/FD).  Then, they get the pattern altitude wrong.

    What does it look like when pattern altitude is otherwise established?  Look up KSGR, Sugar Land Regional, on your Foreflight app.  Foreflight states the elevation as 82′ MSL and the Pattern Altitude as 1,000′ MSL.  Is this correct?  Well, tap that A/FD button again and let’s find out.

    On the second line of the A/FD entry, it says TPA-See Remarks.  Down in the remarks section, we find the following:

    TPA-1000 (918) single engine piston acft, TPA-1500 (1418) for twin and turbojet acft, TPA-500 (418) for helicopters within 2NM.

    Foreflight got it right this time for single engine pistons, but if you are in a twin, the pattern altitude is different.  What’s the lesson here?  Always check the A/FD and don’t always go by what Foreflight says.  The A/FD is always right and usually has a little more detail to help set you straight.

    One last thing.  Both the AIM and the Pilot’s Handbook of Aeronautical Knowledge, when talking about pattern altitude, state, “When operating at an airport, traffic pattern altitudes should be maintained unless otherwise required by the applicable distance from cloud criteria in…section 91.155.”  91.155 defines basic VFR weather minimums.  So, to fully interpret what the AIM is saying, we have to take into account the type of airspace we are in to determine if we can safely and legally operate at pattern altitude at a particular airport.

    For example, let’s say we are at KCVB, the Castroville Airport.  Pattern altitude there is 1,602 feet, which is 829 AGL.  CVB is Class G airspace up to 700 AGL, then Class E above that.  Let’s say there is a 700 AGL broken cloud layer.  Pattern altitude is 829 AGL, so you won’t be able to get up that high with a broken ceiling.  What altitude can you do pattern work at to stay legal?

    Class G VFR weather minimums during the day below 1,200 AGL is 1 SM visibility and clear of clouds.  So, legally, you could fly at 699 AGL (which at CVB would be 1,472 MSL) while in the pattern and be legal.  Safe?  Maybe, but probably not if you are skimming the base of the clouds.  Is 1300 MSL a safer pattern altitude in this example?  Well, that is 527 AGL, so probably not, since towers tend to stick up that high sometimes.

    Let’s go back to KSGR and put a 1,000 AGL overcast ceiling there.  SGR is Class D airspace and we already determined pattern altitude there was 1,000 MSL for piston singles.  VFR visibility and cloud clearance requirements in Class D airspace are 1,000 feet above clouds, 500 feet below clouds, and 2,000 feet horizontally from the clouds with 3 SM visibility.  In order to stay 500 feet below the clouds, you would be flying a 582 MSL pattern.  Safe?  Probably not, though it is legal.

    To summarize, don’t take Foreflight’s word for pattern altitude.  Cross reference the A/FD (it only takes 15 seconds at the most) to verify.  If it’s cloudy, it’s really best to stay on the ground, but if you want to find out your legal pattern altitude with a cloud deck, cross reference 91.155.  I don’t recommend flying below pattern altitude because it is there for a reason.

  • Flying the Hudson River Corridor

    ByAndrew Robinson

    Ever since I moved out to the Philadelphia area, the Hudson River corridor in New York City has become one my favorite places to fly. It’s hard to overstate the beauty of the city from low over the river. Every time I have a family member or friend come to visit, I try and take them over to see the city from the air.

    Each time I fly up the river I can’t believe that we are actually allowed to do so, flying below the tops of the buildings and close enough that you feel that you could reach and out touch them. The draw back to the Hudson River Corridor is that it can be busy, intimidating, and confusing. However, with some reading and preparation, the Skyline flight is easy to do and extremely rewarding.

    Having the right weather is an important first step. The second step is try to arrive during ideal lighting conditions. If possible, select a smooth, calm day to make it easier to maintain a track down the correct side of the river. I always try and target arrival at the city around sunset. The view is spectacular any time of day, but having the lights from the city while the sun is just setting gives the best viewing. I’ve also flown over and done the whole flight after dark, which is always spectacular.

    View of the World Trade Center

    The first method of flying the river is to utilize VFR flight following. If the controllers aren’t too busy, they will provide advisories to aircraft that request the Skyline. The nice thing about doing it this way is that the controller will clear you into the NY bravo airspace and keep you above the traffic flying the Skyline in the VFR corridor below. This is the method that I have always preferred as I enjoy the added benefit of the traffic advisories and it’s nice not to worry about position reporting on the radio.

    If you want to get flight following, head toward the corridor and request the Skyline route with NY Approach. (Remember to stay clear of the Bravo until you’re cleared in!) Once you’re cleared into the Bravo and approaching the corridor, they will hand you off to Newark/ LaGuardia Tower for traffic advisories over the river. I like to approach from the south and ask for a 180 over the George Washington Bridge. This allows me to fly past the city a second time before exiting the corridor over the VZ (Verrazano Bridge) and heading back toward home.

    In red is the path I typically fly. I descend to 1400’ and fly toward the APPLE intersection picking up the shoreline around Staten Island and hugging it until crossing the middle of the VZ. Newark normally clears me into the Bravo at 1400’ or 1500’ to fly up the corridor.

    Pros:

    • Better traffic Awareness
    • No position reports

    Cons:

    • Flying slightly higher reduces the view
    • If the controllers are busy, they may deny your request for advisories  
    • Can be intimidating to talk to NY Approach/ Newark/ LaGuardia 

    The other option is to fly in the VFR corridor. If you want to do it via this method there are just a few things you need to make sure you’re familiar with before you go. When in the VFR corridor you’ll need to make required position reports on a CTAF frequency. Make sure that you have the proper charts and have studied pictures of the landmarks so that you know what you’re looking for. I tend to plan on this as a backup in the event that the controllers won’t give me advisories.

    Pros:

    • Doesn’t require talking to controllers/ class B clearance
    • More freedom to select altitude and routing as desired

    Cons: 

    • Less traffic awareness
    • Required position reporting

    All the requirements and guidelines for flying the corridor can be found on the back of the NYC TAC chart. Any pilot flying the river is required to have one of these or a NYC helicopter route chart on board. If you’re using Foreflight, look in the Documents section under FAA Fly Charts and select the NYC TAC chart in order to read the back of page.

    Below you’ll find examples of the diagrams/ instructions printed on the back of the NYC TAC charts.

    You can see the traffic flow requires northbound airplanes to hug the east side of the river, while the southbound traffic stays on the west side. The VFR reporting positions (listed from North to South) are: Alpine Tower, George Washington Bridge, Intrepid aircraft carrier, Goldman Sachs (clock), Statue of Liberty, VZ (Verrazano Bridge). Each position report should include aircraft type, position, direction, and altitude.

    Other things to be aware of:
    NYC is always a hotspot for TFR’s. There are often TFR’s for baseball games or presidential movements so make sure to check before you head that way. Additionally, there is a speed restriction in place of 140 kts, though I’m not sure why anyone sightseeing would want to go that fast anyhow.

    I realize that all of the procedures and restrictions can be overwhelming, but with the proper preparation, the Hudson Skyline is one of the most incredible places in the world to operate an airplane. There are a lot of things that are easy to get excited about that don’t live up to expectation, but this isn’t one of them. I’ve never taken anyone to the river that wasn’t impressed by what they saw and that’s why I plan to keep going back.

    About to cross the VZ looking north toward the city

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