That Pesky Rudder

ByHank Gibson

Whenever I get in an airplane with a pilot for recurrent training, I can assure myself that I will mention rudder usage more than once during the flight.  If it is in a tailwheel (or if the pilot is doing tailwheel training), I’m going to mention the rudder a lot.  How do I know this?  Because basic rudder skills are actually one of the most difficult things to master in flying.

Let’s start simple.  What does the rudder do?  The dictionary definition is it controls the movement about the vertical axis of the airplane.  If you stick a pole down through the CG of the airplane and rotate the airplane around that pole, this is the vertical axis.  Looking at it another way, the rudder moves the airplane’s nose left and right.  Keep this in mind as we move on.

Rudder

Every pilot thinks about the rudder during the takeoff roll.  Because of the torque effect, the pilot must add right rudder during the takeoff roll to stay on the runway centerline.  Depending on the airplane’s horsepower, more rudder pressure is needed in higher powered airplanes.  The problem usually shows up once the airplane gets in the air.

In the worst situation, after takeoff, the pilot will set both feet on the floor and completely disregard the rudder.  Torque effect and now P-factor are continuing to cause the airplane to yaw left, causing the need for right rudder.  With his feet on the floor, though, the pilot is allowing the airplane to yaw.  It’s not terribly noticeable for him in the front seat, but the back seat passengers (especially in a six seat or larger airplane) are certainly feeling it.

One particular problem spot on the climb is the climbing left turn.  In a climbing left turn, training says to add left rudder since it is a left turn (see below for the reasoning).  But, since the airplane is climbing and therefore experiencing left yawing tendencies due to the aforementioned effects, the pilot needs to continue pressing the right rudder, though the pressure won’t be as much as in a straight climb.  Watch the ball the next time you make a climbing left hand turn and it’ll make a believer out of you.

I find only a handful of pilots are this egregious.  Most pilots have rudder problems in turns and in turbulence.  We’ll tackle turns first.  As we all learned when we first started flying, due to adverse yaw, a pilot must add rudder in the turn’s direction.  Again, this isn’t usually where the problem shows up.  During the rollout is the problem area.

Let’s take a turn to the left.  The pilot rolls in, adding left rudder, arrives at his heading, then begins to roll out with the ailerons.  Left adverse yaw is now being experienced and right rudder is needed to smoothly transition back to level flight.  Need some visual assistance?  Watch the nose the next time you make a turn. If you are working the rudder properly, the nose will pivot on one point in the horizon.  If you aren’t using the rudder properly, the nose will draw a U shape on the horizon.  Try making some turns without rudder, see what it looks like, then use the rudder properly.  You’ll notice a big difference.

Finally, let’s talk turbulence.  As we all know, turbulence in the hot summer afternoon is quite pronounced. When the airplane experiences a bump, it usually doesn’t bounce straight up in the air.  There is usually some kind of rolling motion involved.  As the pilot corrects this rolling motion by moving the ailerons, adverse yaw is experienced (just like rolling into and out of a turn that we talked about above), so rudder is needed.  There isn’t a need to stomp on the rudder or you’ll cause the airplane to severely yaw in the other direction, but rudder pressure is needed.

Final approach is where this gets most pilots.  By controlling the nose and not allowing it to move around on final by using the rudder, this will make your approaches a little more stabilized leading to a more successful landing.

Feeling lost when it comes to the rudder?  Ask your instructor the next time you go fly to do some rudder exercises.  Most instructors don’t emphasize these basic stick and rudder skills which leaves pilots lacking as they move on in their aviation lives.  So make it a point to do some basic rudder work the next time you fly with your instructor.

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  • Upgrading Avionics

    ByHank Gibson

    There are many different ways to upgrade an instrument panel.  Putting in a 696 here, a JPI engine monitoring system there, even an Electronic HSI.  But, if you want to swing for the fences and get a serious upgrade, you have to go for a complete glass instrument panel.  For good measure, you might as well throw in a touch screen GPS while you are at it.

    Which panel to go with?  There are two mainstream options (Garmin and Aspen) and a handful of other companies that make glass panel replacements (Avidyne being one, King for a short period of time at the end of the last decade being another with the KFD 840).  Around 2010, there were a lot of companies trying to get into the glass panel retrofit game, but many of the products didn’t gain a whole lot of popularity, leaving Garmin and Aspen at the top of the heap.

    What about the touch screen GPS market?  Garmin has this pretty much cornered as well, with Avidyne and King just getting into the game.  The gap between Garmin’s GTN series and Avidyne and King is pretty wide.

    Garmin GTN Series

    The answer is pretty easy when it comes to the GPS (go with Garmin!), but not so easy when it comes to the panel.  The G500 and the Aspen Evolution series are both excellent interfaces with strong reliability, so which one do you go with?  Feature-wise, both have a lot of the same features: traffic, weather, terrain, synthetic vision, to name a few.  The presentation for each feature is a little different between the two interfaces.  It just depends on what you like better.

    The nice thing about the Aspen system is you can go glass, but you have options on how much glass you want:  1 screen, 2 screens, or 3 screens?  With the single screen PFD, you have all your instrumentation, traffic, weather, and optional synthetic vision.  You don’t need the synthetic vision for the traffic and weather, as it shows up behind your HSI.  It is an honest to goodness glass panel retrofit.

    When you decide to upgrade to 2 screens, this is where Aspen has a leg up.  The second screen is a completely redundant PFD and, if you get the 2 hour emergency backup battery installed, acts as the backup instrumentation to the main PFD.  This means you can take out the old steam gauge standby instruments.  This helps clean the panel up.

    I personally don’t see the need for 3 screens, but maybe there is someone out there who needs it.

    One selling point that Aspen has over Garmin is the wide variety of autopilots and GPS units that Aspen units are compatible with.  The G500 is only compatible with King autopilots, it’s own GFC 700 autopilot (which would be a retrofit), some Collins autopilots, and the Century 21, 31, 41, and 2000.  This does cover a wide array of autopilots, but it keeps some on the outside.  Aspen, on the other hand, is compatible with most autopilots on the market.

    Finally, let’s talk price.  Going with an Aspen EFD 1000 PFD (this is the single screen Aspen) will run you somewhere in the area of $12,000.  The price will vary based on the shop and the airplane.  When you want to add a screen, it’s an additional $6,000.  This is for the base, so if you want to add weather or synthetic vision, it’ll run you a little more.

    The Garmin G500 comes in around $20,000, again depending on the shop and the airplane.  The screens are bigger on the G500, which is kind of nice, and you are buying a Garmin product, which has a fabulous track record in the aviation industry.

    Decisions, decisions.  There really is no wrong answer here.  Both are excellent products with very good track records.  Both have really nice features and don’t hardly fail.  Really, the choice comes down to what you want.

    Need training on your upgraded GPS or glass panel retrofit?  Contact Texas Top Aviation for thorough training on your new avionics today.

  • Coflyt Ownership App

    ByHank Gibson

    A new app came out last year that fits a need for many owners. Coflyt, available on the Apple App Store for $14/month for up to two airplanes, helps immensely with staying organized. Those questions of, “When is my oil change due?” or “Has the plane had it’s IFR inspections?” are easily answered by checking the app instead of having to dig through maintenance logs.

    Not only does Coflyt help keep track of maintenance, but it also houses squawk lists that owner’s can send to maintenance shops as well as keeping track of Airworthiness Directives. If the pilot remembers at the end of flights to put the amount in, it even shows how much fuel is remaining in the airplane.

    For flying clubs and partnerships, it provides easy scheduling without having to share calendars. Payments can also be taken and flights tracked. No more paper flight sheets after flights to track down.

    As a pilot, it helps immensely to be organized. For $14 a month ($36/month for partnerships or flying clubs), that’s a small price to pay.

  • Breathing…It’s The Difference in Engine Performance

    ByJoe Casey

    The PT6 engine that’s found on the Jetprop and Meridian is designated a -21, -34,-35, or a -42A.  The Continental engine on a Malibu is either a TSIO 520 or a 550.  What’s the difference? Why should I care? Most pilots don’t understand the difference, but it’s pretty easy to understand…and it’s all about breathing.

    Whether a piston or a turbine, the engine has a ratio of fuel/air that works best.  For a piston model, we can make adjustments to this ratio by adjusting the mixture.  In climb we use a richer ratio to help cool the engine, and in cruise we lean the mixture to save fuel since we don’t need the extra fuel for cooling (due to higher speeds which cools the engine). In the turbine, the ratio is set and there’s nothing that can be done about it…except climb to a higher altitude.  But, more about that in a second..let’s go back to the piston discussion…

    Piston: A Continental 520 engine and the 550 engine are flown exactly the same.  On takeoff, both will develop 310HP (38″MP with the 520, 35.5″MP with the 550).  So, why would a pilot want a 550 in his airplane as opposed to a 520?  The answer is breathing.

    A 520 is named appropriately because the engine displaces 520 cubic inches of air with each complete cycle of all 6 cylinders.  To determine the displacement, just figure the bore (diameter of the cylinder) and the Stroke (how far the piston travels in the cylinder) and plug the numbers into this formula:

    CID = Bore X Bore X 0.8754 X Stroke X # of Cyl.

    Here’s the bore and stroke of the Continental 520 and 550 engine:

    TSIO 520:  Bore = 5.25″ and Stroke = 4″
    TSIO 550: Bore = 5.25″ and Stroke = 4.25″

    So, you can see the two engines are exactly the same except the 550 has a little longer stroke, and therefore displaces a little more air.  Said another way…it the sucks the air into the engine a little better.

    So, with this knowledge, the ability for the engine to breathe becomes a little more clear.  Both a 520 and a 550 will perform exactly the same until the point that a 520 simply cannot suck enough air and begins to develop less MP as a result.  For most 520 engines, this will happen somewhere around 18,000 ft.  But, it is dependent upon a myriad of factors including: health of the engine, altitude, temperature, and atmospheric pressure. When the 520 hits this point, the throttle can be full-forward, but the engine will not develop full MP, but some number that is less.  I’ve seen a max MP at FL250 in a 520 Malibu to be about 31″MP.  So, you can probably guess that the rate of climb will correspondingly suffer as the engine develops less MP.  How do we fix this problem?  Enter the 550…

    Since the 550 displaces more air, the engine will maintain max MP to a higher altitude.  When the 520 begins to develop less power at about FL180, the 550 engine will be able to continue to maintain 35″ at a higher altitude.  Make no mistake…the 550 will also hit an altitude where is cannot develop 35″MP, but this altitude will probably be nearly FL220.  So, the 550-powered Malibu will reach cruising altitude faster than the 520.

    But, at cruise both engines are pulled back to 30″MP.  So, either engine will deliver the same cruise speed because they are both able to develop 30″MP at any altitude.  Does it really matter if you’ve got a 520 or a 550 engine?  Answer: not much.  Both are excellent engines and both will deliver the airplane to the destination, but if the chosen altitude is above FL180, the 550-powered airframe will probably arrive a few minutes earlier.  Which would I want if I were purchasing an airplane?  It’s not a big enough deal, IMHO.  I’d select the best airframe/engine/prop combination and not put much weight into the 520 vs. the 550.

    Turbine world: So, how about the -21, -34/35, and -42A compare?  Here, there’s  big difference, but it’s still all about the breathing.  A -21, -34/35, and -42A are all derivatives of the famous PT6 family of engines, and all are designed to be 1000+SHP engines de-rated to fit the airframe.  For instance, the -42A engine is 750SHP when mounted on a King Air 200, but the same engine is derated to 500SHP when mounted on the Meridian.  Ditto with the -21 and -34/35 engines…all are de-rated.  So what’s the difference? Breathing…

    At the lower altitudes all will develop their maximum rated SHP, meaning they will all develop maximum torque.  And, down low there’s plenty of air to breathe so the engine has no problem developing that torque at a low ITT.  But, as altitude is gained, the engine must suck more air to develop the same torque, and the ITT goes up.  At some point in the climb (depending upon altitude, temperature, pressure, and IAS) the engine will not be able to produce max torque without exceeding Max ITT.  At this point, the engine cannot breathe any more (suck in anymore air), and the power (torque) developed falls off.  With the -21 engine, the power falls off quite dramatically because the engine simply cannot breathe well.  It is a smaller engine and more air cannot be forced into the compressor section.  For the rest of the climb the engine is “ITT limited” and the performance will suffer.

    The -34/35 engine is a little bigger and will develop maximum power (torque) to a higher altitude.  And, when the torque does drop off (as altitude is increased), the rate of decrease is less because it can breathe easier due to it’s larger size.  Guess what? The -42A will beat out the others and develop max torque to an even higher altitude.  With this decrease  in torque available also comes a welcome friend…less fuel burn.  Altitude is the friend of any turbine pilot, and he/she will climb to the highest altitude possible to save on fuel.

    The end result is the -21 powered Jetprop will cruise at 238 KTAS (in the summer) with a fuel burn of only 28gph.  The -34 will have higher torque than the -21 and will develop more SHP and will have a higher cruise (260 KTAS in the summer) with a correspondingly higher fuel burn (32gph).  The -42A will be breathing easily at higher altitudes, and will develop the most torque, but with a fuel flow of 39gph.  The Meridian (with the -42A) will not out-perform the -34/35 Jetprop in cruise purely because the Meridian is much heavier.

    Just remember…fuel flow in a turbine is always commensurate with its ability to breathe and a turbine’s ability to breathe is a function of the engine’s ability to breathe.

    With this knowledge…let’s check your understanding.  Answer this question: Will a Jetprop cruise faster in the summer or winter?  Remember, cold air is more dense than warm air, and an engine will develop power according to it’s ability to suck in air.  More air available, more power available.  Answer: Winter.

    A good analogy: I’m a Cross-fitter (meaning I do crossfit workouts a lot).  In the gym we have various workouts that test a person’s ability to perform.  Guess who usually does the best?  Right…the guy who can breathe the best.  A person is nothing more than an engine…we intake air and combine it fuel and burn it to develop energy.  In Crossfit, the person with the biggest engine (muscles that can develop power) that can sustain power (good aerobic capability) will win almost every time.  The only variables then are genetics (how well-made is the engine), flexibility (you’ve got to be able to get into the position), and skills (there are more efficient movements).  A good Crossfitter will work hard on mobility, skill, and try to increase the bodies ability to increase capacity through a tough workout.

    To get maximum performance, the pilot cannot change the engines skill or mobility (at  least not without an engine change!), but a thorough understanding of the how the engine breathes will help him/her use the power that is available to the fullest.

    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.

  • Cirrus SR22 Partnership in Houston

    ByHank Gibson

    Ever wanted to be a Cirrus owner, but the economics of being a single owner just don’t make sense for you? If you’re in the Houston area, you now have a chance to join a Cirrus SR22 partnership at the West Houston Airport, KIWS.

    The group, CirrusShare, is a 4 member group, but one of the members is looking to sell his share.  The airplane is a 2007 G3 SR22.  It is in excellent condition, with dual WAAS 430s and air conditioning.

    If you would be interested, please contact Texas Top Aviation for more information.

    N578AG

     

  • Beechcraft Bonanza Ownership

    ByHank Gibson

    If you walk up to any Beechcraft Bonanza sitting on the ramp at an airport and ask the owner, “How do you like your Bonanza?” be prepared to stand there and listen for 15-20 minutes while he brags about his airplane.

    V35 Bonanza

    The thing about Beechcraft Bonanza owners is that they are almost a part of a cult. They will tell you up and down why the Bonanza is the best airplane out there. They’ll tell you why all the others don’t even come close. They’ll tell you about the payload, the six seats, the variety of configurations you can select from, the ability to land pretty much anywhere. By the time you walk away, you will probably be convinced to buy one yourself.

    Bonanza’s are great airplanes. For those of you new to the single engine piston market, a good comparison for a Beechcraft Bonanza would be a Suburban. Not the flashiest ride out there, but extremely capable, comfortable, and family conscious. If you’re hauling a load, you’ll take a Bonanza over a Cirrus or Mooney any day. Have six people? No problem!

    One of the best things about a Beechcraft Bonanza is the variety of designs. Four seats, six seats, long range tanks, tip tanks, turbo charged, normally aspirated, steam gauge, G1000, Aspen or G500 retrofitted, dual yoke, single yoke, leather, cloth, and a variety of different colors out there on the market make finding a Bonanza that fits your need pretty easy.

    When it comes to picking out an airplane, the first question is always the mission. If you’re thinking about a Beechcraft Bonanza, you’ve already determined you need something with a good useful load. Do you need four seats or six? Depends on how often you’ll be carrying someone or how new of an airplane you want. Older Bonanzas have four seats, but a lot have had significant updating. Newer A36 and B36 Bonanzas have six seats, but are going to cost you more.

    Beech Bonanza

    Do you need a turbo charged Bonanza? If you’re in a high elevation area or expect to visit the mountains a lot, then absolutely. If you want a better cruise speed and don’t mind a little less useful load, then go for it. If you’re more concerned about being able to load it up and you aren’t going to cross the Rockies often, then normally aspirated is what you want. You’re probably looking at about 160-170 KTAS with the normally aspirated whereas you get between 180-190 KTAS at altitude with the turbo.

    Do you need tip tanks? Tip tanks have two advantages. One is the most obvious: you get to carry more fuel, therefore you get to go farther without having to stop (or when you stop for the bathroom, you don’t have to fill up with gas). The other advantage is you get a bump up in useful load. I talked to a Beechcraft Bonanza owner a few weeks ago who had tip tanks on his. He told me max gross on his Bonanza was 3,800 pounds and was eligible for an upgrade of up to 4,000 pounds and all it took was paper work for the STC. That’s quite a bit of load!

    G36 Bonanza

    Are Bonanzas hard to fly? When moving up from a typical 172 or Cherokee that most people learn to fly in, it does take some adjustment. But, with good Bonanza training from a qualified Bonanza training instructor, then the transition is no problem. There are tons of resources out there to aid all future and present Bonanza owners in their foray into the Bonanza nation. With the American Bonanza Society and Bonanza Pilot Training, there is no lack of training, thoughts and opinions.

    In need of an airplane that can pretty much do whatever you need? Then a Bonanza may be right for you.

     

  • Texas STOL Roundup

    ByHank Gibson

    Looking for a fly in this fall?  Check out the Texas STOL Roundup at the end of September in Hondo, KHDO.  Interested in entering?  All are welcome!  There are several different categories including LSA, Experimental, and others.  Come in for a fun weekend and see how short an airplane can be landed!

    There will be bands, a STOL seminar, and even a hangar dance.

    Fly in or drive in.  Camping will be available on the airport.

    For more information, you can visit the event website.

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