Oh, Deer (Part 2)

Shock Cooling in a PA46

ByJoe Casey October 25, 2018

We’ve all heard it said…”reduce the throttle by no more than 1-inch every minutes to ensure you don’t shock-cool your engine”. Does this advice apply to a PA46 engine? Can a PA46 engine (Lycoming 540 or Continental 520/550) really be shock-cooled? How should the engine temperature be managed?

Metals expand and contract with temperature, and the various metals in an air-cooled aviation engine expand and contract at a different rates. Shock-cooling supposedly occurs when the engine changes temperature quickly and the different metals in the engine cool (and therefore change shape) at different rates. When the change occurs dramatically supposed scoring, rubbing, and marking of the metal can occur, which can cause catastrophic results.

So, let’s back to the original question…can a PA46 engine suffer shock-cooling and should a pilot operate the engine so as to avoid shock cooling? Simply put, I’ve never seen nor heard of any piston PA46 engine suffer shock-cooling. In 5000+ hours flying the piston PA46 and 16 years of flying/managing/training in the Malibu/Mirage/Matrix, it simply has not happened to me nor anyone I know. Does it mean that it cannot happen or has never happened? No. But, it is certainly not a prolific threat to our fleet.

Should the owner/pilot operate the engine with a cautious eye cast toward the potential of shock cooling? Well, sort of…but, let’s flesh this out. My suggestion is that a pilot should operate the engine with conservatism in movement of temperature, but only because this is a good operating practice with any machine, and any flying machine is (by definition) not “overbuilt”. And, there are many ways to change the temperature of the engine…not just by reducing power. Here’s a partial list of ways to cool your PA46 engine:

• Reduce power: Obvious…yes. When the engine produces less power, less heat is generated. Reducing power in a piston engine will almost always result in less temperature.
• Lower the nose: By descending (and leaving power in a cruise setting) the airspeed will increase and cool the engine.
• Enrichen the mixture: Fuel has a cooling effect on the engine, so the richer the mixture the cooler the engine.
• Lower the landing gear: Yes…you read that right…engine cooling will occur when you lower the landing gear because more air will flow over the cylinders. Notice the landing gear doors on the PA46 have air louvers. Air flows into the engine nacelle on the front, passes down through the cylinders (along with the oil cooler, intercoolers, and other components) and then out the louvers of the closed gear doors. When the landing gear is lowered the “back door is opened” and a LOT more airflows over the cylinders.

My suggestion is that a pilot only perform ONE of these actions at a time when beginning a descent. This suggestion was presented to me by Chad Menne (Owner, Malibu Aerospace) some time ago and I’ve operated engines this way ever since. If you are at a higher altitude and simultaneously reduced the power, lowered the landing gear, started a big descent, and enrichened the mixture in one flail swoop, I think there’s a chance that your engine would suffer some negative effects that could be called “shock cooling”. So, when you do start a descent, pick one “cooling action” to accomplish at a time. I’m sure you’ll not hurt your engine.

Simply put, shock cooling is not a huge factor in the PA46 community, and a PA46 pilot does not need to be overly cautious. The “one inch per minute” rule may apply in some other airframes, but in the PA46 world it is not applicable.

Joe Casey’s aviation story began in 1990 with his first flight near Nacogdoches, TX in a Cessna 172. From lift-off, Joe knew he would have a lifetime passion flying just about anything that will leave the ground…He was completely hooked.

Along with being an FAA Designated Pilot Examiner (DPE), Joe is an ATP/CFI-AHMG and Commercial Rotorcraft/Glider Pilot in the civilian world and also a UH-60/AH-64 Pilot-in-Command/Instructor/Examiner Pilot in the US Army Reserves.  His passion for the last 19 years, however, has been the PA-46 Malibu/Mirage/Matrix/Jetprop/Meridian. Has has amassed over 6,500 hours in various PA-46 airframes and believe it to be one of the finest flying machines available for the serious cross-country pilot with an eye for efficiency.

Now, Joe has flown more than 12,200 hours in just about every imaginable environment. Whether providing initial/recurrent training in the PA-46’s, TBM’s, instructing in NVG’s in a UH-60 Blackhawk, flying the King Air series of airplanes, giving tailwheel endorsements, or taking kids flying for the first time, he simply loves flying machines and the people who fly them.

Maintaining TKS Panels

ByHank Gibson June 14, 2016June 14, 2016

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.

MODAERO NextGen Aviation Festival

ByHank Gibson March 8, 2016March 7, 2016

Looking for something different to do this Spring Break week?

Consider checking out the First Annual MODAERO NextGen Aviation Festival in Conroe, TX.  It’s a fly in event, complete with camping opportunities, at the Lone Star Executive Airport, KCXO.  The festival itself is being held right next door to the airport at the Lone Star Convention Center.

What’s the draw, do you ask?  Not only are there going to be representatives from all the major aircraft manufacturer’s (along with tons of airplanes), there will be a multitude of speakers and live music.  There are even drone races!  The live music sets the event apart from the well known national fly in events like Osh Kosh and Sun N Fun.  It’s a different type of Festival, geared toward the younger generation of pilots.

For more information or to register, check out MODAERO’s website.  The festival runs from Wednesday through Saturday, March 16-19.

The Importance of Slowing Down

ByHank Gibson June 4, 2018June 4, 2018

Technology has made our job as pilots simpler, streamlined, and safer.  With all the new GPS & autopilot technology that seems to come out every month, flying an airplane is getting easier every day (and when I say flying, I mean programming!).  I can’t tell you the last time I actually used a VOR for navigation, other than a practice approach.  The AIM even has guidance in it now allowing pilots to use the GPS overlay on a VOR or LOC approach instead of switching to the actual NavAid on the course needle (you have to WAAS in order to legally do this).

I hear the argument already.  I am young (31) and used to all the different touchscreens because I have grown up with them.  Tech is nothing new to me.  It’s not that easy for everyone, I do understand.  There is also the argument that all the tech causes pilots to not know how to fly the airplane, which is also valid. This is why I put an emphasis on hand flying in any kind of training I do.

For the sake of argument in this article, yes, I am young and I adapt to technology pretty easily.  I’m not afraid to press buttons to figure out what they do, but I usually do it while sitting on the ground with a GPU hooked up (or I go look in the manual).  And yes, all the autopilot ability has caused a decrease in base pilot skills.  I actually encourage every customer I have to go get a tailwheel rating so that they can actually learn how to fly better.  You don’t use a rudder much in a Cirrus compared to a Super Cub or a Citabria.

What I want to focus on for a few minutes is how to alleviate the frustration that comes with getting so wrapped up in the technology when it doesn’t do something that you want it to, or the wrong button gets pressed, then you end up somewhere you had no intention of being.

The biggest thing a pilot can do when it comes to technology is NEVER to get in a hurry.  Good training is first and foremost, but, after that when flying without an instructor or even in recurrent training, SLOW DOWN and think through what you are doing and what you want the system to do.  This will alleviate a ton of frustration.

It can be very easy in hot, turbulent weather to get tuned in to the GPS programming, trying to do five or six different things in the span of five or six seconds, before looking up and realizing that plane is 500 feet off altitude (without an autopilot) or you blew through the course you were supposed to be intercepting (with an autopilot).

What I teach is to slow down, whether or not you have an autopilot, and do one thing at a time.  Once that item is done, look up at the instruments or the horizon, check on things, make sure the airplane is still flying properly, then do the next thing.  Don’t try and do a bunch of things all at once or in a hurry.  It will usually get you off course and off altitude, plus it distracts the pilot from his main job:  Flying the airplane.

So, next time you want to do something on your GPS, pause, take a breath, think through what you want to do, then do one item at a time.  The outcome will be less frustrating and you’ll keep flying where you want to go.