Cirrus Electrical System Health

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.

Textron Aviation’s New Single Engine Turboprop

ByHank Gibson May 29, 2016

An 8 seat, cabin class, single engine turboprop is set to come to market in 2018 from the new aviation conglomerate Textron Aviation (Textron owns Cessna, Hawker, and Beechcraft).  Details were announced last week at the European Business Aviation Conference and Exhibition.  The as yet unnamed aircraft will be equipped with Garmin’s G3000 avionics and will be outfitted with a GE 1,240 Shaft Horsepower engine.

The GE engine will be equipped with a FADEC (Fully Automated Digital Engine Control) computer that will allow the pilot to make all necessary power adjustments using just one lever.

Range will be about 1,600 miles at 285 knots, giving the airplane the same legs as a PC12 at slightly faster speeds, but a smaller cabin.  The cabin will be equipped with a belted lav if desired.

To read more, check out the AOPA Article here.

Flight Service Station

ByHank Gibson October 29, 2017

When is the last time you talked to the Flight Service Station?

Believe it or not, FSS is still in existence.  Over the past 10 years, they went from FAA run, the being bought by Lockheed Martin, to now being privately run by a company called Leidos. 1-800-WX Brief will get you connected with a weather briefer, but you’ll hear “Leidos Flight Service Station” now when the briefer picks up.

Since the advent of Foreflight, most pilots these days get their weather briefings digitally on the iPad. Foreflight has come a long way since it’s inception.  The briefing part of their Flights page is quite comprehensive, with lots of information, and counts as a legal weather briefing (which pilots are still required to get before a flight).

Why does a pilot even need to call Flight Service?  Well, when’s the last time you tried to interpret everything the Briefing on Foreflight told you?  As I said before, it’s a lot of information and a lot of it can be confusing.  Pilots are not fully trained on interpreting Prog Charts and getting an overall weather picture for a flight.  A weather briefer is.

I have over 5,000 hours and I still call a weather briefer before almost every flight.  On the way to the airport is a great opportunity to get a weather briefing.  I get a great picture of what’s going on in my area or over my route, frontal movement, bad weather areas, and whether or not it’s a good idea to even take off. Calling in the car alleviates the main complaint I hear about calling the Flight Service Station, which is it’s inconvenient and causes a delay since you have to call them on the phone.

I don’t do much private pilot training anymore, but when I do, I always teach my students how to get a weather briefing from the Flight Service Station.  I’ll show them how to get the briefing on Foreflight too, but usually their eyes bug out of their heads when they start trying to read everything.  A breathe of relief is released when I tell them there is a trained professional just a phone call away who can clear everything up.

The other thing that the Flight Service Station provides that is important to a lot of folks are PIREPs.  It’s vital in sketchy weather areas for the FSS to get a report of what’s actually going on in the air.  This helps other pilots out greatly as they are getting information about icing, cloud bases and tops, turbulence and a myriad of other things from airplanes who are actually in the conditions.

Finally, the most used portion of the Flight Service Station is the Clearance Delivery line (888-766-8267). At airports without a tower or a clearance delivery frequency, with IFR conditions present, the only way to get your IFR clearance is to call Clearance Delivery.  Yes, it can take a little time sometimes, but you will get a clearance every time, unlike taking off and trying to dodge the clouds without hitting anything, while trying to call Center on the radio (which isn’t safe or legal).

Been a while since you’ve talked to the Flight Service Station?  Give them a call, either on the phone or on the radio.  Odds are, they are bored and just wanting someone to talk to, just like you are on that long cross country flight!

Checkout 1800WXBrief.com to see all the cool stuff the Flight Service Station does.

A Flying Car in the Future?

ByHank Gibson July 31, 2016August 11, 2016

EAA Airventure at Osh Kosh always draws great innovators every year, leading the aviation consumer to discover something new and different.  Flying cars have always been a dream for the everyday pilot.  Why not fly to work?  Why not park the plane in the parking lot?  Why not drive from the runway onto the freeway?  All excellent questions!

Well, Samson Motorworks is trying to make those dreams a reality.  Samson’s Switchblade flying car is in the (hopefully) finally stages of development this summer.  The company expects to be able to conduct test flights early next year, then begin selling the experimental kit.

The Samson Switchblade will be in the Experimental category, but Samson has a builder assist program that only adds $20,000 to the final cost of the kit.  The total price of the kit, which comes 49% completed and only takes 3 weeks to complete with the builder assist program, comes in at $140,000.  That includes the engine, avionics (it’s equipped with Dynon’s 7″ Skyview glass panel display, a Dynon radio and transponder, a Dynon intercom, a Dynon AOA, an iPad mini, and an ADS-B GPS), and the builder assist program.  Similar to a Cirrus, it is also equipped with a Ballistic Parachute Recovery system.

The Samson Switchblade has several different engine options, including a supercharged, liquid cooled, V-4 similar to a Corvette engine that will produce 190 HP.  Max cruise in the air should be around 170 knots.  The Switchblade will hold 30 gallons of mogas, burn 9 GPH in the air, and get 35 mpg on the ground.  The gross weight will be 1,750 pounds.

How does the car to plane transition happen?  Samson has developed a fly by wire system to retract the rudder down while the car is in drive mode.  The wings use a mechanical linkage to fold up into the belly.

There are several different packages for the Samson Switchblade:  the Snowbird, the Aurora, and the Trek options.  Details can be found on Samson’s website.

I, for one, will be keeping an eye on the freeways next summer to keep an eye out for cars sprouting wings.  No more traffic jams!