Checking The Stall Warning Horn

ByHank Gibson

When a pilot first glances at the title of this article, the first thought that probably goes through that pilot’s head is, well that’s easy.

And it is, if you are flying a high wing Cessna. On other airplanes, there are a few tricks to checking the stall warning horn. If you get them wrong, you’re liable to get a bill from your maintenance shop for an hour of labor for a problem they couldn’t duplicate.

Cirrus SR22

Let’s start with the Cirrus. On the pre-FIKI Cirrus aircraft, there was a small little hole in the wing that contained a diaphragm. That diaphragm sensed a change in airflow at a certain angle of attack just below the critical angle of attack and set off the stall warning horn. Unfortunately, the only way to check that is to suck on the hole during pre-flight.

I don’t. I verify the hole is clear and that’s about it.

On the FIKI Cirrus aircraft, there is actually a stall warning vane. It looks like a high wing Cessna vane, but if you turn the batteries on and try and get it to come on during your light and pitot heat check, nada.

Here’s the trick, and the checklist doesn’t do a good job of describing this.

  • Turn on the Avionics Master
  • Turn on the speaker
  • Put the flaps to full
  • Then move the stall warning vane and you’ll hear the horn

The speaker and the Avionics Master are so you can actually hear the horn (if you had the headset on while you were doing this, the speaker would be unnecessary). The flaps have to be full because the pitch attitude for the critical angle of attack is lower with the flaps down, so the horn goes off when at a different angle. You then don’t have to use as much force to push the vane.

Piper PA46

The early -310P Malibus are pretty simple and straight forward. Move the vane, get the horn.

In the -350P, you can’t get the horn to come on by moving the vane. So, Piper put a stall test button that’s hidden underneath the upper left side of the instrument panel. Push that to test the horn. On the G1000 PA46, it is located directly above the PFD. On the Avidyne, it’s below and to the left of the pilot’s yoke.

Testing the stall warning horn is a very important part of pre-flight. A pilot needs to know if the aircraft is close to a stall. The advent of Angle of Attack indicators in small, GA aircraft, have added a greater awareness to the angle of attack during all phases of flight to avoid those stall spins.

If the stall warning horn goes off or the AOA shows yellow, lower that nose immediately.

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  • 3 Tips to Better Landings

    ByHank Gibson

    In my 3,000+ hours of flight training, I have developed some tips and tricks to help people fly better.  With teaching landings, I have 3 specific tips that will make smoother landings every time, guaranteed.

    A Good Pattern

    A wise flight instructor whom I would love to give credit to (but don’t know who it is!) once said that a good landing starts off with a good traffic pattern.  So true!  A good landing all begins with the setup.  This is true for a VFR rectangular traffic pattern or an IFR instrument approach.  Flying the proper speeds and being at the proper AGL altitudes helps immensely in making a good landing. Being at 600 feet AGL on a 1/2 mile final (or the alternative of 60 feet off the ground on a mile final!) makes it hard to make a good landing.

    Proper Use & Understanding of Pitch and Power

    Once flaps are used in the pattern, the plane is now on the back side of the power curve (or in the region of reverse command).  Power is now being used to control the plane’s rate of descent while pitch is being used to control airspeed.  The key is, both pitch and power work together, so if the pilot changes the power, he’ll also need to change the pitch and vice versa.

    The common mistake I see here is when the airplane gets low on final, the pilot tends to (quite naturally) pitch up.  All this does is bleed off airspeed and cause the airplane to sink faster.  The proper input would be to add power, then adjust the pitch for airspeed.

    Look Down the Runway

    Now that we have gotten to the point of the round-out and touchdown, it’s the most important part.  The best thing the pilot can do to make the best landing possible, is to look at the trees at the end of the runway.  When I worked with college students, I told them to find the owl in the trees at the end of the runway.

    The tendency is to stare at the pavement (or concrete) the whole way down to the landing.  When a pilot’s eyes are fixated on the ground, this destroys his depth perception and causes a level off too low to the runway, resulting in a 3 point landing and/or a bounce.

    By looking at the trees at the end of the runway, this gives the pilot much better depth perception and allows him to properly judge where to level off the airplane.

    The question now is when should the pilot start looking at the trees?  My recommendation is crossing the threshold of the runway.  For some, it works better to start looking at the trees when turning final.  Others, right before the level off.  Regardless, find that owl!

  • Garmin GFC 700 Autopilot

    ByHank Gibson

    The Garmin GFC 700 Autopilot is an amazing machine.  Fully digital and fully integrated with the Garmin G1000 glass panel, it makes a pilot’s workload a lot easier, especially in busy airspace.

    I train a lot of pilots in airplanes that have the Garmin GFC 700 autopilot.  The Cirrus SR22, the Columbia 350 & 400, the G36 Bonanza, and the Piper Mirage and M350 to name a few.  The most common problem I see for pilots transitioning into the Garmin GFC 700 equipped aircraft is that it doesn’t act like other autopilots.

    STECs and DFC 90 Autopilots function like this:  you push the button for the mode you want on the autopilot controller and that turns the autopilot on.

    Not so on the Garmin GFC 700.  If you push the button for the mode on the GFC 700, then the flight director engages, but not the autopilot.  This confuses folks a lot who move up from different autopilots because their autopilot primacy side of their brain is telling them the autopilot is on whenever they push one of the buttons on the GFC 700 controller.

    Here’s an example:  A pilot has just departed and is ready to turn on course.  In his old airplane with an STEC 55x autopilot, the pilot pushes the direct to key to go to his first waypoint, then pushes NAV on the autopilot controller and the STEC 55x comes on and starts flying on course.  Then he presses VS and ALT to initiate a climb.

    With the same scenario and a Garmin GFC 700 autopilot, the same pilot (who is used to a 55x), pushes the direct to key, then pushes NAV on the autopilot controller and pushes IAS or FLC to initiate the climb.  He lets go of the flight controls thinking the autopilot is engaged.  The airplane starts nosing over and he starts panicking.

    Why did this happen?  The pilot in the second scenario never pushed the AP button on the Garmin GFC 700 so the autopilot never engaged.  All he did by pressing the NAV button and IAS button was to turn the flight director on.

    How to remedy this?  Get in the habit of checking your scoreboard.  On the top of the G1000 or Garmin Perspective PFD, there is an autopilot annunciation strip (or scoreboard as I like to call it).  In the very middle of the scoreboard is an area to show if the autopilot or flight director is engaged.  AP means the autopilot is on; FD means the flight director is engaged but the autopilot is not.

    I teach pilots to be in the habit of checking your scoreboard each time you get done pressing buttons on the autopilot controller to ensure the Garmin GFC 700 is in the proper mode.  This saves some of those panic moments when it is supposed the AP is engaged, but it’s only the FD.

  • Cirrus CAPS Pull in Arkansas

    ByHank Gibson

    Cirrus CAPS pull #55 took place at the beginning of November over Fayatteville, AR.  From initial reports, it appears a clamp broke on the oil cooler, causing a loss of oil pressure.  It does not appear that the engine immediately quit, but an annunciator alerted the pilot that the engine was losing oil pressure.  At this point, it appears the pilot elected to do an emergency descent to an airport below him, but ended up not timing it right, missing the airport and pulling the parachute.

    As an experienced Cirrus flight instructor, there appears to be some suspect decision making in handling this operation.  I teach in a Cirrus that if an oil light comes on, given that a pilot has some altitude to work with, it is a better option to physically shut the engine down, leaving control of the situation in the pilot’s hands.  This way, the pilot knows when the engine is stopping and is prepared for it, instead of the engine acting erratically and causing problems on the descent.

    After checking the engine gauges and shutting the engine down, a pilot should establish best glide first, not nose down and descend at a high rate trying to make an airport.  Best glide gives the pilot many more options and a lot more altitude to work with, further allowing him/her to plan how to make an airport directly underneath the airplane.

    To pontificate, it seems that if the pilot had adjusted the plane to best glide, instead of performing an emergency descent, there is the possibility that Drake Field would have been reachable, the chute would not have been needed, and the driver of the truck would not have had to visit the hospital.  Hindsight is 20-20, but this may be an overall training and decision making issue that may need further emphasis.

    The initial NTSB report as well as a link to the CBS story is below.

    http://www.cbsnews.com/live/video/pilot-forced-to-deploy-emergency-parachute-in-arkansas/

    NTSB Identification: CEN16LA026
    14 CFR Part 91: General Aviation
    Accident occurred Tuesday, November 03, 2015 in Fayetteville, AR
    Aircraft: CIRRUS DESIGN CORP SR22T, registration: N857SW
    Injuries: 3 Minor, 1 Uninjured.
    This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
    On November 3, 2015, at 0950 central standard time, a Cirrus SR22T airplane, N857SW, descended under the canopy of the cirrus airframe parachute system (CAPS) and landed on a road in Fayetteville, Arkansas. The pilot, pilot rated passenger and one person on the ground received minor injuries. One passenger in the back right seat was uninjured. The airplane was substantially damaged. The airplane was registered to WG Aviation LLC, Rogers, Arkansas, and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident and an instrument flight rules (IFR) flight plan was filed. The flight departed from the Bentonville Municipal Airport (VBT), Bentonville, Arkansas, at 0934 and was en route to the Waco Regional Airport (ACT), Waco, Texas.

    According to the pilot, after departure from ACT he leveled off around 10,000 ft mean sea level (MSL) and was in “VFR on top” conditions. The pilot noticed that the crew alerting system (CAS) flashed a yellow caution light for oil pressure; the engine was still producing power. The pilot notified air traffic control (ATC) of the issue and received vectors to the nearest airport, Drake Field Airport (FYV), Fayetteville, Arkansas. The pilot descended and maneuvered toward FYV as the CAS indicated a red warning light for oil pressure, which had dropped below 10 psi. The engine was producing inconsistent power as the airplane descended to 3,300 ft and FYV was still not in sight due to cloud coverage. The pilot was unable to maintain altitude and the airplane’s stall warning horned sounded. The pilot deployed the Cirrus airframe parachute system (CAPS) and descended to the ground. During the landing the airplane collided with a truck and then came to rest on a four lane road.

    At 0953, the weather observation at FYV reported wind from 190 at 9 knots, gusting to 17 knots, 10 miles visibility, clear sky, temperature 61° F, dew point 57° F, and altimeter setting 30.11 inches of mercury.

    An initial postaccident examination was conducted on November 4, 2015, in Fayetteville. Engine oil was observed on the underside of the fuselage. The oil cooler cross fitting was broken and oil was observed in the engine compartment.

    The airplane’s recoverable data module and three data cards were removed and sent to the NTSB Vehicle Recorders Laboratory for download.

    The airplane has been retained for further examination.

  • The PIC Isn’t Always the Pilot Who Took Off

    ByAnne Pargeter

    You are at cruising altitude and your flight is going just as planned. All of that can change, sometimes without much warning, and you, the non-pilot, are now in charge. Would you know what to do?

    This was a scary thought for me until I attended a seminar developed for the non-flyer at a Cirrus Owners Pilot Association (COPA) fly-in. Cirrus is the only small plane with a parachute as standard, so I thought all I had to do in an emergency was pull the chute. It’s a little more complicated than that!
    I learned the vast majority of pilot incapacitation happens when the plane is at cruising altitude, so there is time to find a solution.

    anne-pargeter-picture

    I was taught ten basic steps to follow to bring the plane safely to the ground.

    • First attempt to revive the pilot. If he is choking, it is possible to do a Heimlich maneuver from the side. This may dislodge whatever is blocking his airway and solve the problem. If he is experiencing hypoxia, turn off the heat, open all vents, and, if you have on board oxygen, use it. Also, if you can, get instructions on how to descend to a lower altitude. If the pilot is unconscious due to a heart attack or other medical emergency, there are still things you can do from the right seat.
    • Engage the autopilot if it isn’t already on and move the pilot off the controls. *
    • Ensure you are connected to the radio. If you hear ATC or other pilots, you are.
    • Send an electronic trouble message. Set the transponder to 7-7-0-0 to identify your plane to ATC. This will cause your plane to be highlighted on ATC radar screens.
    • ATC will most likely contact you asking what is your emergency. If this does not happen, you will need to transmit a Mayday call. All non-pilot passengers should know how to use the radio to get help, if they know nothing else.
    • With help from ATC, decide where you want to go.
    • Use the autopilot to fly in the direction suggested by ATC. I was taught that ultimately the choice of where to deploy the parachute is up to me because I am now the PIC, pilot in command.
    • Ensure that seat belts are secure and the emergency hammer is between your legs (so you have it to break a window to escape if needed).
    • Pull the parachute handle.
    • On the way down, shut down the engine and brace for impact.
    • After landing, move away from the plane, into the wind. Stay nearby and wait for help.

    The seminar covered specific procedures to accomplish these basic steps, what to do if you don’t get a response from ATC, what to say in a Mayday transmission, how to fly a heading, how to check fuel levels, shut down the engine, etc. After the seminar, I felt much more comfortable about what to do if my pilot suddenly lost consciousness.

    I was also told to practice what I had learned to avoid panicking in an emergency situation. There are so many things the person in the right seat can do under normal circumstances to practice. Learn how to set heading bugs, learn where the plane’s Electronic Locator Transmitter (ELT) is located and how to activate it. This will help rescuers locate the airplane. Learn how to assess your fuel levels. Practice making routine radio transmissions. Observe what your pilot does and ask questions if you don’t understand something.

    Knowing what to do in an emergency situation will give you a sense of control over what will happen to you, your pilot, and any passengers on board your plane. If you have never considered taking a lesson or two for the non-pilot, find yourself an instructor, and learn what you need to know for your plane. Hopefully you will never have to use it, but if you do, you will be ready to be the PIC who lands the plane.

    Anne and her husband Stephen are the proud owners of a Cirrus SR20. They plan to put the airplane to better use once Stephen retires. Anne has a background in desktop publishing and writing.

  • Piper PA46 Partnership in San Antonio

    ByHank Gibson

    A Piper PA46 partnership is being formed in the San Antonio area. Two to three partners are being sought to purchase either a Piper PA46-310P Malibu or a ’90s model Piper PA46-350P Mirage.

    The Piper PA46 Malibu is the original Piper PA46 airframe. It is equipped with a Continental TSIO 520, 310HP engine (though many have been upgraded to the Continental TSIO 550C engine, which is a great upgrade), is complex, and pressurized (the best feature about the airplane!). The six seat airframe travels around 185-190 KTAS at FL200 on 16-17 GPH, giving an incredible range with 120 gallons of fuel.

    The Piper Mirage is what Piper designated the PA46 when it switch to the Lycoming TIO 540 350HP engine in 1989. The airframe remained the same, but the engine eeks out a few more KTAS at 22-25 GPH depending on how high the cruise altitude is.

    Both the Piper Malibu and the ’90s model Mirage are equipped with the KFC 150 autopilot. A lot of the Piper PA46 airframes still have a Garmin 530W/430W or dual 430Ws, but a large number have been upgraded to the Garmin GTN 750/650, while a few have opted for the Avidyne IFD 540/440 GPS units. There are a fair number still with steam gauges, while some have upgraded to Aspen units or the Garmin G500 or G500TXi.

    If you are located in the San Antonio area and interested in a 3-4 way partnership on a Piper PA46, please Contact Us. The purchase price will be between $300,000-$450,000, so only interested parties that can afford a budget of $100,000-$150,000 please.

    The plane will be based at Stinson Field (KSSF) or New Braunfels (KBAZ).

  • 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.

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