L-3 Lynx Transponder Line

An Educational Runup

ByHank Gibson July 23, 2020July 17, 2020

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.

Scud Running

ByHank Gibson June 2, 2015

I was speaking with a pilot a few months back who was not instrument rated.  He was telling me of his flying experience while continually speaking fondly of scud running.  He told me several stories, most of the time with a smile on his face, about scud running to his destination while staying clear of clouds.  While he was talking, my mind was cycling through the numerous accident reports I’ve seen where a scud running VFR pilot has crashed into terrain or an obstacle.  Needless to say, scud running is not a very good idea.

This pilot’s stories got me to thinking, how common is the practice of scud running amongst VFR only pilots?  As an instructor, I always teach my private students about personal minimums and making that no-go decision when clouds are below those personal minimums.  The act of scud running falls under several of those dangerous pilot mindsets, get-there-itis, invincibility, and macho-ism, to name a few.

To bring everyone on the same page, let’s define scud running.  Wikipedia has a very good definition:

Scud running is a practice in which pilots lower their altitude to avoid clouds or instrument meteorological conditions (IMC). The goal of scud running is to stay clear of weather to continue flying with visual, rather than instrument, references. This practice is widely accepted to be dangerous, and has led to death in many cases from pilots flying into radio towers and high tension wires; however, even instrument-rated pilots sometimes elect to take the risk to avoid icing or embedded thunderstorms in cloud, or in situations where the minimum instrument altitudes are too high for their aircraft.

To put some numbers with that definition, a scud running VFR pilot would takeoff with a 1200-1500 foot ceiling and stay 700-1000 feet above the ground, right in the area where towers, hills, and rapidly rising terrain reside.

How do we change this mindset?  Well, if someone has been scud running for years without incident, the practice becomes normal, like the pilot I mentioned above.  The mindset of invincibility sets in and the practice continues.  This particular pilot can also lead other pilots to adopt the same practice, encouraging them that nothing will happen to them, since we all know that our pilot peers know better than our flight instructors (insert heavy sarcasm here).

In order to change this mindset, instructors need to emphasize personal minimums from day one.  This includes ceilings, visibility, and winds.  For a seasoned pilot, a review of accident statistics might help the process.

Scud running is not a safe practice.  If you’re a scud runner, you need to rethink your attitude.  Is getting there really worth it?

Still not convinced?  Read this pilot’s experience from AOPA.

Avidyne IFD 440 Receives Certification

ByHank Gibson July 1, 2015

Avidyne’s plug and play replacement for the Garmin 430, the Avidyne IFD 440, finally received certification from the FAA last week.  The touch screen GPS unit is being marketed as a simple swap out for the Garmin 430.  This release follows up Avidyne’s release last year of the IFD 540, also a plug and play replacement, but for the Garmin 530.

The features and touch screen of the GPS units sound quite nifty, but it will be hard for Avidyne to compete with the GTN 750 and 650 from Garmin.  The unit prices for the IFD 540 and 440 will be less (and installation is simpler), but we will see how the company does.

The STC allows for installation in 1,000 makes and models of aircraft, according to the company, so there are a lot of possibilities for installs.

In conjunction, Avidyne also released a new version of it’s software for both GPS units.  According to Avidyne, this will unlock multiple features that enhances the capabilities of both units.

To read more on the IFD 440 and it’s bigger brother, the IFD 540, check out Avidyne’s website.

Bruce’s Custom Covers

ByHank Gibson February 15, 2018February 26, 2018

I have used a few different sun shields in airplanes in my flying career.  I have found one that I really like. Bruce’s Custom Covers knocks it out of the park for usability and ease of storage.

Let’s start off with functionality.  Like other window sun shields, Bruce’s Custom Covers fit very nicely into the airplane glare shield and side windows. Depending on the type of airplane you have, some of the window covers use the suction cups and others don’t.  I recently had 2 customers order from Bruce’s, one that owns a P210 that uses the suction cups for all windows, including the glare shield, and the other owns a Cirrus which doesn’t use the suction cups on anything.

They work great.  They do the job of blocking the sun and keeping the cabin much cooler while the airplane is sitting on the ramp.

The thing I like best about Bruce’s Custom Covers is their storage.  Other sun shields require you to roll them up and lash a tie around them. Bruce’s, on the other hand, come folded very neatly in a black canvas bag.  The folded covers don’t take up nearly as much room as the rolled up covers, plus they are really easy to just fold up and store.

Bruce’s Custom Covers also sells plugs for cowling, pitot tubes, etc., as well as aircraft exterior covers.

Bruce’s Custom Covers gets my recommendation for anyone wanting to get some new sun shields.  For those of you in Texas, you know you need them!

Texas Top Aviation Now Offers Piper PA46 Training

ByHank Gibson August 15, 2017July 14, 2026

Texas Top Aviation is proud to announce that we now offer Piper PA46 Training in the Malibu and Mirage.  Our Piper PA46 training is provided with the same excellent & professional approach that has become our hallmark.

The four-day format of this course allows time to answer all of your questions about your new airplane.  The Texas Top Aviation Piper PA46 training course leaves you with a confidence and understanding that will help you enjoy your Malibu or Mirage even more.

New avionics have you scratching your head in confusion? No problem. Texas Top Aviation is well versed in the latest Garmin and glass panel instrumentation.

If you are in need of recurrent training in your PA-46, Texas Top Aviation would be proud to help with that as well. Consider us your one stop shop for Piper PA-46 training.

For more information, check out our Piper Malibu/Mirage Training page.

Contact us today to schedule your Piper PA46 Training!