Shock Cooling in a PA46

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.

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  • Preventing Gear Up Landings

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    Image credit: Aviation Consumer

    On the evening of November 3rd, 2015, I was returning to my home airport of Lancaster from Pittsburgh in my company’s Aerostar, after being out on charter all day. It was dark out as I entered the traffic pattern at Lancaster. After an uneventful approach, I was cleared to land behind a Mooney. The spacing looked good as I turned final, but, as I was nearing the threshold, I started to become concerned that the Mooney wouldn’t be clear of the runway in time for me to land. At that moment, over the radio I heard an uncomfortable transmission from the Mooney pilot: “Tower, Mooney ABC has landed gear up.”

    It took the tower controller a minute to grasp what was going on, and I was on about a 1-2 mile final when I was instructed to go around. Thankfully, the Mooney came to a stop in such a position that I was able to use the other intersecting runway, and was on the ground only a few minutes later. I can assure you, however, that I’ve never checked my “3 green” so many times in one traffic pattern as after that incident. Thankfully, no one was hurt, but there sure was an impressive amount of emergency equipment on the runway as I taxied back to my hangar.

    In aviation, there’s a saying that goes: “There are two types of pilots. Those who have landed with their gear up, and those that will.” I don’t like that saying. The potential of a gear up landing (as a result of pilot error) is something that has always been a risk that I have worked hard to avoid. Not only is a gear up landing embarrassing; but it’s also an extremely expensive black mark on any pilot’s career.

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    Not a good day. (Photo credit: http://www.newsday.com/long-island/suffolk/plane-lands-at-republic-with-no-wheels-1.2735131)

    According to a July 2006, article in Aviation Consumer, the estimated cost of repairs following a gear up landing for an A-36 Bonanza would be about $27,000 and about 3 weeks of down time. 25 years ago, even my beloved E33 Bonanza was the victim of a gear up landing. While it was neither me nor my dad flying our airplane that day, the event stays in its history and reduces its value should the time ever come to sell it.

    That incident in 1990 resulted in approximately $25,000-30,000 in repairs. The cause of the incident was classic: the pilot put the gear down at the normal time, but then had his downwind extended by tower. He brought the gear back up to fly the longer downwind, but forgot to put it back down later when he was cleared to land. Like many pilots, he had a set routine time when he normally put the gear down, and when his routine was changed, he didn’t remember to lower the gear once more.

    Unfortunately, no matter what experience level one may be at, no pilot is immune to the possibility of such a mistake. The following are 5 tips that I have learned in my time flying that have helped myself and others minimize the chance of a gear-up landing occurring:

    1. Know your aircraft systems: What are the operating perimeters on your airplane’s gear warning system? Most airplanes have a designated speed or power setting at which the gear warning horn will sound in the event that the gear isn’t down and locked. In the Aerostar that I was flying, the gear horn was supposed to come on at 15” of manifold pressure with the gear up, but in practice, it didn’t come on until much lower than that. It has since been adjusted, but at the time it was important for me to know that if I had left the gear up, the horn wouldn’t have sounded in a timely enough manner for me to go around, much less lower it prior to touchdown. Most likely it would have just added to the noise of metal on concrete as I pulled the power all the way back in the landing flare.
    2. Don’t override gear-up warning systems: They were put there for a reason! Even if you’re out doing maneuvers and the horn is blasting in your ear for half an hour, resist the temptation to simply pull the circuit breaker or push the warning silencer to make it shut up. If a pilot disables the gear-up warning horn and then later forgets to put the gear down on landing, he or she will have a much worse headache on their hands than the one that the horn would have given them.
    3. Use your checklists and memory items: It doesn’t matter how much a pilot knows about his or her airplane, or the procedures for it. Distractions happen. Mistakes Happen. Always consult the checklist for confirmation that you’ve accomplished all the essential tasks before landing. Additionally, if you haven’t already, work on developing call outs which you perform out loud regardless of whether you are alone in the airplane or not. Whenever I’m landing an airplane, I start with my flows, go through my GUMPS (Gas-Under carriage- mixture- props- seat belt) checks, then do the printed checklist, and finally when on short final I call out “short final, cleared to land, three green.” I’ve had several passengers tease me about doing the “three green” call out while I was flying aircraft that didn’t have retractable landing gear. But, I’d much rather be in the habit of checking every time regardless of what I’m flying than forgetting to check when it is necessary.
    4. Use your available resources and develop healthy habits: If I have someone riding with me, I generally ask them to confirm that there are 3 green lights glowing on the instrument panel. Even if that person isn’t a pilot, they will probably enjoy the opportunity to be involved, and it’s a good way for me to stay in the habit of checking the gear lights to ensure that everything is properly down and locked. I’ve also found that intentionally leaving your hand on the gear lever until you have gear safe lights is a good idea. Forcing yourself to keep your hand on the handle until you have the all important lights obligates you to actually observe the indications instead of simply throwing the lever and moving onto something else. This way, if you only get an indication of 2 greens you’ll be aware of it right away and have more time to respond appropriately. It also helps you to learn the normal length of time it takes for the gear to extend or retract, which will be helpful to you to be aware of any abnormalities in the gear system.
    5. Upgrade your aircraft’s gear-up warnings: There’s a variety of ways you can improve your aircraft’s ability to warn you of a potential gear-up landing. For student pilots or pilots new to complex aircraft, it could be something as simple as a red post-it note on the panel to remind you to verify the gear position prior to landing. Or, if you own an aircraft that doesn’t have an effective way to warn the pilot of a gear-up landing, consider investing in an aftermarket gear-up warning system – surely the extra price of such an upgrade is a small amount next to the cost of repairing the damage from a gear-up landing!
    Crash recovery and emergency management crews survey a C-17 Globemaster as it rests on Bagram Air Field's active runway Jan. 31 after landing with its landing gear still up. More than 120 Airmen, Defense Department civilians and contractors successfully removed the crippled aircraft from the runway Feb. 2 and restored full air operations shortly thereafter. The "belly up," or no landing gear, recovery effort that began here Jan. 30 was the first time in the airframe's 16-year Air Force history. (U.S. Air Force photo)
    It can happen to anyone! The gear handle in this C-17 was in the “UP” position. (Photo Credit:https://theaviationist.com/2009/02/09/c-17-gear-up-landing-in-bagram-images/)

    Always remember, regardless of experience, no pilot is immune to the possibility of a gear up landing. The best way to safeguard yourself is to discipline yourself in the use of flows, checklists, and call outs. Things like gear warning horns, visual reminders, and other systems are a useful back up, but they shouldn’t be relied upon to save your bacon if you don’t get the gear down at the proper time. Fortunately, in most gear up landings, the pilot and passengers are able to walk away uninjured – but that doesn’t lessen the embarrassment or financial burden of the event. So, keep your chin up, your gear down, and remember….THREE GREEN

  • Flying To Mexico

    I took a Piper Malibu to Cabo San Lucas a few weeks back.  This was my second trip flying to Mexico, but the first where I arranged everything.  Cabo is a beautiful place and the MMSL airport is a fabulous facility. For those who haven’t been fying to Mexico before, MMSL is the place to go.  The folks there are extremely helpful and do most of the paperwork for you.  You just have to pass along your information to them.

    Mexico Flying

    Flying to Mexico and back out is different than flying in the US.  First of all, don’t forget your passport. The authorities on both sides frown upon that.  You’ll probably get sent back to the US (or sent back to Mexico if you are on your return trip).  Your aircraft also needs, Mexican insurance (talk to your US insurance agent) a radio license, and a customs decal.

    Second, you’ll have to file an ICAO specific flight plan for flying to Mexico.  This is available on Foreflight now, but I really like Fltplan.com’s way of doing it.  I don’t fly internationally enough to remember what everything means, but Fltplan.com does a great job of walking pilots through the the different classifications.  It’s almost impossible to get confused.

    Third, you have to fill out an eAPIS form.  This has to be done at least 24 hours prior to departure from the US, but it can be done as far in advance as you’d like.  If your departure time changes or your passengers change, you can edit the eAPIS form to bring it current.

    Flying to Mexico IFR is a lot simpler than flying VFR.  I have only flown IFR and it is very easy.  I’m already on a flight plan, already squawking a discreet code, and already on radar, so there really isn’t any way I can mess up the ADIZ penetration.  I really recommend going in and out of Mexico IFR instead of VFR.

    Once you land in Mexico, you have to close your IFR flight plan.  The tower doesn’t do this for you.  After clearing customs, you’ll have to pay a landing fee and sign your flight plan confirming you have arrived and closing it out.

    When departing, you have to file another eAPIS 24 hours in advance.  Wherever you plan on clearing Customs in the US, you’ll need to call the Customs office no less than 1 hour, but not more than 23 hours before arrival.  It’s called an Advanced Notice of Arrival.

    You’ll need to fill out a paper flight plan before departing, clear customs again to leave, then away you go.

    There are a lot of really fun getaways in Mexico and flying there doesn’t have to be difficult.  When you have the right information, flying to Mexico can be a breeze!

  • Chuck’s Aircraft 10 Year Anniversary Fly In

    Chuck’s Aircraft, the Austin Cirrus Service Center located at the Austin Executive Airport (KEDC), is celebrating it’s 10 year anniversary this month. What better what to celebrate than to fly in for Texas BBQ? That’s what they thought too!

    Chuck’s Aircraft will be hosting its 10 Year Anniversary Fly In on Friday, June 25th from 1pm to 5pm on their ramp at EDC (see airport diagram below). Chuck’s Aircraft always provides quality maintenance for Cirrus and other aircraft, so come show your appreciation for them.

    Please RSVP to erin@chucksaircraftllc.com. Hope to see you there!!!

    Chuck’s Aircraft is the hangar circled in green
  • Cirrus Pilot Proficiency Program (CPPP)-Conroe, KCXO

    The Cirrus Pilot Proficiency Program is coming back to the Lone Star Airport in Conroe, TX (KCXO) on October 23rd-25th.  Wondering what the CPPP program is?

    “CPPP offers a weekend event for Cirrus owners and their partners that focuses on Cirrus-specific knowledge and flying proficiency.  We bring some of the most experienced flight instructors who regularly teach in all kinds of Cirrus airplanes flown for all kinds of missions.  We have prepared an extensive syllabus of ground courses that complement the transition training and delve into areas of greatest need for Cirrus pilots.” (from CirrusPilots.org)

    CPPP

    The weekend starts off with a group dinner on Friday night. The Saturday morning ground session focuses on General Aviation Safety with special focus on the Cirrus accident statistics.  Normal and emergency procedures are also reviewed.

    In the afternoon on Saturday, the attendees are split into two groups.  The first group has a myriad of options for ground sessions covering all topics related to Cirrus aircraft and operations.  The second group flies, then they switch for the second 3 hour session.  Sunday brings the same split, with more courses offered and more flying.

    While the Cirrus pilots are flying and learning more about their airplanes, CPPP offers a Partner in Command course for flying partners on Saturday.  This allows flying partners to be more comfortable in the airplane and teaches them what to do if something were to happen to the pilot.

    All in all, attending a CPPP will improve both Cirrus knowledge and Cirrus flying skills.  It’s highly recommended for all Cirrus pilots.

    To register for the CPPP event in Conroe, check out the CPPP website.

  • US Aircraft Expo Returns to Addison

    The 2022 Fly In Season kicks off March 4th-5th with the US Aircraft Expo at the Addison, TX Airport (KADS). Cutter Aviation at KADS will be the host for the event. All the major and minor aviation manufacturers will have static aircraft displays. Come see all the new Cirrus innovations, the Piper M600, and the Diamond DA62. All the latest and greatest technology will be available for your viewing enjoyment.

    If you are planning on flying in, the FBOs at ADS are Million Air and Atlantic.

    The event will run from 10am-3pm on both days, March 4th and March 5th.

    For more info, check out the US Aircraft Expo website.

    Don’t forget to check out other big fly in events in 2022: Sun N Fun, the Texas Top Aviation Fly In at Santa Fe, and Osh Kosh!

  • Beware of the Lunch Monster

    He prowls around, preying on innocent pilots.

    He’s very sneaky, creeping unexpectedly and attacking after the propeller begins to turn.

    He’s very cunning, veiling his intentions until, BOOM, he attacks.

    Beware of the Lunch Monster!

    Whenever I am doing a full day of training (which is usually how transition training courses are planned out, in full day sessions), I always plan a lunch stop.  My metabolism has the speed of a rocket ship, so I get hungry and need some sustenance in the middle of the day.  I have a running list of airports to stop at that have good lunch spots at them or nearby, so my customers and I usually end up at one of those airports.

    Almost without fail, if a customer is having an excellent flying morning, nailing all the procedures, picking up all the techniques, and overall, flying pretty well, then eats lunch, the afternoon doesn’t go quite as well.  Doing some of the same things we did that morning, but the customer’s performance isn’t quite as good.  Most of the time, it’s just a brain lockup or landings aren’t quite as squeaky as they were in the morning.

    Part of it is fatigue after flying for 2-3 hours in the morning.  The other part is what I call the Lunch Monster.  Eating a big lunch can sap away brain power and cause a person to lose energy around 2-3pm, leading to an afternoon lull (or the Lunch Monster attacking!).

    According to Forbes.com:

    Diet contributes to energy levels too. “Eating a lunch that is too big is the most common reason for feeling sleepy in the afternoon,” says Rebecca Solomon a nutritionist at Mount Sinai Hospital in Manhattan. “All your energy goes into digesting the enormous meal.”

    The goal is to keep the body’s Cortical and Cortisone levels even since they’re the hormones released by the body in reaction to stress–they produce the fight or flight response. Their levels are elevated when you have sugar, caffeine and processed food, so you feel awake and energetic. But a few hours later, when those levels drop, you’re sluggish.

    Solomon recommends eating a meal that’s balanced with healthy fats (from olive oil or avocados, for instance) with protein and healthy carbohydrates (whole wheat bread or pasta). The portion will vary for people of different sizes, but a general rule is you should be hungry about four hours after the meal.

    Another healthy eating habit: Consume small portions of foods throughout the day, including almonds, carrots and hummus and fruit. Enjoy lunch around 1:30 or 2 p.m., just before the time you normally feel fatigued.

    Now, most of the stops on my list of restaurants don’t fit the bill of healthy fats and healthy carbohydrates (plenty of protein, though, especially the BBQ joints).  For those days, bringing along a snack like almonds or dried fruit is a great idea to munch on mid-afternoon.  Trimming down the amount eaten at lunch helps a lot too.

    So, the next time you have a long day of flying or training, beware the lunch monster and prep some good snacks when your flight instructor says you’re stopping for BBQ!

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