Pitch + Power = Performance

ByHank Gibson

My first chief flight instructor had an addage he would impart to his flight instructors when we began working at that flight school. “Pitch + Power = Performance” he would tell us. Then he’d glare at us and follow up with, “nobody teaches that right, so make sure your students know it.”

Now, having been a CFI for seven years, I would tend to agree with him. I have moved on from doing mostly primary training to transition training. Transition training is taking someone who is already a pilot and teaching them how to fly a different type of airplane. In jets, you get a type rating. In piston engine airplanes, there is no FAA requirement to go through any type of extra training as long as you are rated in category and class (eg. single engine piston). But, insurance companies know that Mr. Fresh Private Pilot can’t just hop from a Cessna 172 into a Cirrus SR22 or a Bonanza, so they require transition training before insuring those pilots.

What did my chief instructor mean when he imparted his wisdom? He was speaking about a particular phase of flight, the final approach phase, regardless of whether it’s a VFR approach or an IFR approach. The pitch of the airplane and the power setting of the airplane have to be utilized together to achieve the proper speed and descent rate (performance).

VFR

On the final approach leg of a VFR pattern, most piston engine aircraft are configured with landing gear down and flaps down in the landing position. This puts the airplane on the back side of the power curve in the region of reverse command. In the region of positive command, in cruise, for example, the more power you add, the faster you are going to go and, if you pitch up, you will go up and you pitch down, you will go down. But, they work together (if you point the nose down, you will accelerate unless you reduce the power); remember, Pitch + Power = Performance.

diamond-landing

In the region of reverse command, the pitch controls the airspeed and the power controls your rate of descent, but, again, they work together. Let’s say the airplane is 5 knots above it’s approach speed on final. Initially, the pilot will need to pitch up slightly to bleed off that airspeed. The airplane will want to climb, so as he is pitching up, he’ll need to make a slight power reduction to stay on glide slope.

Alternatively, let’s say the airplane is high, but is on speed. The pilot will make a power reduction to descend to the glide path, but he’ll also need to pitch down to maintain the proper airspeed.

What you don’t want to do is this: if the airplane is high on final, don’t push the nose down to try and get down. This does cause the airplane to lose altitude quickly, but the airspeed increases quickly. With a higher airspeed, the airplane has a lot more energy to dissipate when it gets to the runway, meaning you’ll float longer which can lead to forcing the airplane down or using up too much runway and not being able to get the airplane stopped in time.

IFR

On an instrument approach, you are on the front side of the power curve. When trying to stay on glide slope, the power is controlling the speed of the airplane and the pitch is keeping the airplane on glide slope. This can be a little bit confusing for VFR pilots transitioning to instrument approaches as they are not used to being on the front side of the power curve.

Keeping in mind that Pitch + Power = Performance, let’s put the airplane above the glide slope on an ILS approach. In order to get down to the glide slope, the pitch needs to be lowered as much as needed (it’s always better to pick a pitch attitude to fly and see if it is working to bring the glide slope back to center. If it doesn’t work, pick a new one. Don’t just push the nose down until the glide slope moves) and the power needs to be reduced to maintain airspeed (again, pick a specific power setting). Once the glide slope centers, then the pitch will be raised slightly and the power will need to be increased to hold glide slope and speed respectively.

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  • 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.

  • AOPA Air Safety Foundation Survival Seminar

    ByHank Gibson

    The AOPA’s Air Safety Foundation will be returning to Texas this coming week with their After the Crash:  Surviving An Aircraft Accident seminar.  Though aircraft accidents are rare to most pilots, they still happen.  It is best to be prepared with the proper knowledge and supplies in case you are stranded in a remote area while awaiting help to arrive.

    The seminar will cover the following items:

    • How and what to pack in a survival kit
    • Ways to help search parties find you
    • What to do first immediately after the off airport landing
    • How to survive will awaiting rescue

    The seminar will be put on in Houston, San Antonio, and Austin on three consecutive nights, the 20th-22nd, so everyone will get a chance to attend.  The location and times are below.

    No signup is necessary, just show up and be ready to learn.  The seminar does count for WINGs credit and there will be a sign in sheet at each event.

    The AOPA Air Safety Foundation puts on numerous seminars throughout the country during the year covering a wide variety of topics relevant to general aviation pilots.  The content is always interesting and the presenter always knowledgeable and entertaining.  Hope to see you there!

    Tuesday, January 20th

    Wyndham Hotel, Houston West
    14703 Park Row Blvd.
    Houston, TX 77079
    7:00pm-9:00pm

    Wednesday, January 21st

    Doubletree Hotel, San Antonio Airport
    37 NE Loop 410
    San Antonio, TX 78216
    7:00pm-9:00pm

    Thursday, January 22nd

    Omni Hotel, Southpark
    4140 Governor’s Row
    Austin, TX 78744
    7:00pm-9:00pm

    For more information on the event and the locations, please click here.

  • Landing Light Replacement

    ByAndrew Robinson

    One evening this summer, my wife and I were flying down the southern shore of Long Island in my father’s E33 Bonanza. We enjoyed the sunset as we flew westbound and our plan was to fly the New York Hudson corridor, where we would arrive just after dark. As we approached New York’s airspace, two voices in my head started having a debate.

    The first voice said: “You should turn on your landing light when you get to New York to make the airplane more visible.”

    The other voice said: “That’s true, but I bet you’ll burn the landing light out”

    Well, as it turned out, both voices were right. My landing light fired right up when I needed it to fly the Hudson, but when it came time to land back home I had no such luck. Unfortunately, this was not the first time that I had been given the chance to practice my blackout landings. This Bonanza model has only one landing/ taxi light which is mounted in the lower cowling behind the propeller. This location is less than ideal because the filament in the bulb is fragile and can be damaged by engine vibration.

    We landed uneventfully and after putting the airplane away, I decided it was time to look into upgrading the lighting to something a little more modern. I was unsure of my options, but seeing as the airplane needed a replacement bulb regardless, it seemed like a good opportunity to make a change.

    After doing a little reading, I learned that HID or LED landing lights would be the best solution to my problem. I was familiar with LED aircraft lights, but had never heard of HID before.

    Here is what I learned:

    HID Landing Lights

    HID, or High Intensity Discharge landing lights, create light by arcing electricity through a sealed gas capsule. They are brighter than LED and traditional incandescent, and the light created more closely resembles the look and feel of sunlight. HID installations require a ballast to carefully regulate the flow of electricity to the gas capsule and also require a “warm up” period after being turned on in order to reach their full brightness.

    Fitting an aircraft with HID landing lights tends to be more expensive and time consuming than installing an LED light and would likely require involvement by an A&P/ IA. However, if you want the brightest light available, HID is probably the best bet.

    Pros

    • Brighter, more natural looking light
    • Draws less power than standard bulbs
    • Long bulb life
    • Does not generate much heat

    Cons

    • More expensive than other lighting options
    • Lights must “warm up” after being turned on
    • Cannot be pulsed easily
    • Cost/complexity of installations

    LED Landing Lights

    LED, or Light Emitting Diode landing lights, have no filament and work by moving electricity through diodes which are connected into a circuit. These lights have become very popular for many uses due to their simplicity, low cost, and brightness.

    While not as bright as HID light, the LED lights require no “warm up period” and can be easily pulsed. LED lights draw much less power from the aircraft’s electrical system than traditional bulbs and boast incredible life length. LED bulb installation is very simple and can often serve as a direct replacement for the original lights.

    Pros

    • Instant light (no warm up)
    • Incredible life length (>5,000 hours)
    • Low Cost
    • Simplicity of installation
    • Can be pulsed easily
    • Low power draw

    Cons

    • Not as bright as HID lighting

     

    After weighing the options, I decided to replace the incandescent bulb in the Bonanza with an LED bulb. I read the reviews online and talked to some of my friends who work in aviation and eventually decided on the Lycoming Alphabeam. The Alphabeam is FAA/PMA approved and is available through Aircraft Spruce and other aviation parts vendors. The bulb cost around 250-300 dollars and I was able to install it as a direct replacement for our old light. All I had to do was take the old one out, put the new one in, and make a logbook entry.

    Below are some pictures of the installation:

    Last weekend I finally had an opportunity to take the airplane out after dark and see how the new light compared to the old one. I am pleased to say that it did a wonderful job and exceeded my expectations.

    If you are interested in seeing a side by side comparison of the different lighting options, a quick Google search should provide what you are looking for. In my own experience, I would say that the LED light was brighter than the old light and did a very good job illuminating the taxiway and runway. It was extremely nice not to be concerned that my light wouldn’t work as I was setting up for landing at an unfamiliar field after dark. I also enjoyed feeling that I had the option to leave it on during climb and cruise in order to increase my visibility to other aircraft.

    Many models of aircraft have multiple landing/ taxi lights installed which greatly reduces the likelihood of having to land without one. In our case, spending the extra money to upgrade to the LED bulb made sense because of the desire for increased reliability. If you are looking for a relatively inexpensive way to upgrade your airplane, LED or HID lighting may be something to consider.

    Andrew Robinson is a 135 Charter Pilot and flight instructor who lives with his wife and 2 daughters in Pennsylvania.  He flies Pilatus PC-12s and instructs in Beechcraft Bonanzas.

  • The Diamond DA62: The Ultimate Twin

    ByHank Gibson

    Late last year, the Diamond Aircraft Corporation announced a brand new twin engine, the Diamond DA62. At first glance, this is a pretty cool airplane.  It seats 7 passengers, spread out amongst 3 rows, with 2 massive doors, leading to an “SUV” type feel, according to Flying Magazine.  That is only one of the “neato” features of the Diamond DA62.

    The thing that will make pilots believers is the fuel burn.  According to Flying Magazine, which did a test flight of the airplane, at 14,000 feet and 60% power, the airplane was only burning 12 GPH, but still doing 170 KTAS.  Remember, this is a twin.  That’s about the same as a normally aspirated Cirrus SR22 at the same altitude.

    Diamond DA62

    How does Diamond do it?  Jet A.  The company put two Austro AE330, 170 Horsepower, Jet A burning piston engines on the Diamond DA62.  You may say, well, yeah, at 60% power, that’s great, but I want to go places. How much fuel does it burn then?  Even at max continuous power of 95%, it’s still only burning 18.5 GPH total and cruising at 195 knots.  Paying Jet A prices, that’s pretty sweet.

    The range on the airplane is quite nice too.  Again, according to Flying Magazine, the range with full fuel (86.4 gallons with aux tanks) is about 1,300 miles.  You can carry the whole family too, as the full fuel payload is 1,000 pounds.  Golf clubs?  No problem.  Just stick them in the nose.

    The Diamond DA62 is probably one of the easiest twins to manage, engine-wise, too.  The Fully Automated Digital Engine Control (FADEC) system that Diamond installed leaves the pilot with only 2 power levers, instead of 6 on the typical piston twin.  All that needs to be done at cruise is set a percent power and the FADEC computer does the rest.

    Need air conditioning, built in oxygen, and TKS?  Diamond can set you up.  The G1000 system complete with digital backup instruments is standard in the airplane.  What more can you really ask for?

    If you haven’t figured it out, I really like this airplane and would be aching to fly it.  I enjoy the DA40 and have a good amount of DA42 experience, but I’d really like to hop in a Diamond DA62.

    Read the whole Flying Magazine article here.

    Sources:  Flyingmag.com

  • Cirrus Approach

    ByHank Gibson

    Earlier this year, Cirrus debuted it’s new Learning Management System (LMS), Cirrus Approach. For several years, Cirrus has led the way in online systems training while using several different platforms for it’s LMS. Cirrus Approach is the culmination of lots of sampling and tinkering, and boy, did Cirrus knock it out of the park.

    For those of you unfamiliar with the Cirrus training program, here is the quick rundown. When a pilot who has no Cirrus time buys a Cirrus aircraft, initial transition training is required to familiarize the pilot with the aircraft systems, speeds to fly, power settings, etc. The Cirrus Transition Course is a 3 day that gets a VFR pilot up to speed in the airplane. Under the Cirrus Embark program, those 3 days of training are covered by Cirrus and free to the new owner.

    If the pilot is an IFR pilot, then the 5 day Cirrus Advanced Transition Training Course is required. If the pilot has Cirrus experience, but with a different engine or avionics configuration, there are courses for that too. The Cirrus Embark program covers 3 days of training for most courses for a new Cirrus owner.

    As part of the aforementioned courses, there are systems to learn about and procedures to understand. This is where the Cirrus Approach LMS excels. Cirrus has done a great job of putting together lots of good videos (that are actually interesting but not annoying) on the airplane, systems, how to fly it, etc. for each course. It cuts down greatly on the time that the training instructor has to spend on the ground with the pilot since the pilot has already compiled knowledge through Cirrus Approach.

    Cirrus Approach is accessible online at learning.cirrusapproach.com. To get access to the courses, create an account, then select the Learning Catalog. The courses are categorized based on the type of training (Transition, Advanced Transition, Avionics Differences, Airframe & Powerplant Differences, Recurrent, and Specialty), then further broken down into the type of airplane, engine and avionics (eg. SR22T G6 Perspective+). Make sure the correct engine and avionics configuration is selected! Notice, there is a difference between the SR22T and SR22 (Turbo & Non-Turbo).

    Anyone can do the specialty courses. I would highly recommend for everyone to take the Engine Management course as well as the Icing Awareness Course for you TKS and FIKI operators. The Takeoff & Landing course is a good refresher course for a pilot who hasn’t done any training in a while.

    The Recurrent Training courses are encouraged for all Cirrus pilots. There is an IFR Refresher, a VFR Refresher, and a Skills Refresher. These are recommended to rotate through with a CSIP (Cirrus Standardized Instructor Pilot) on a yearly basis. With a little extra ground, a Flight Review and an IPC can be accomplished yearly using these courses.

    Interested in Initial or Recurrent training in your Cirrus using Cirrus Approach? Contact Texas Top Aviation today!

  • The Aviation Insurance Landscape

    ByHank Gibson

    This is a re-post from Assured Partners Aerospace’s 2nd quarter Newsletter. The full newsletter can be found on Assured Partners website.

    Until the war in Ukraine, the aviation insurance market could be described as “stabilizing” after a couple years of volatility with higher premiums and tighter underwriting. However, and hopefully perhaps only for the short-term, the Ukrainian war immediately brought uncertainty back into the worldwide aviation insurance market. 

    According to Business Insurance, “the impact of Russia’s invasion of Ukraine represents the biggest potential loss to the aviation war market since 9/11.” One leasing firm alone has reportedly already filed a claim of approximately $3.5B for aircraft and engines they say have effectively been seized by Russia. And, because the aviation insurance arena is so small, what happens around the world at this magnitude can have cascading, detrimental effects on the US aviation insurance market.

    In addition, the well-publicized spike in fuel prices could have another cooling effect on aviation operations. Generally, less air activity combined with higher operating costs equates to more frequent requests for reduced coverage, taking premium dollars away from an already-small market.

    Aviation insurance buyers should therefore remain on the alert throughout 2022 for potentially quick changes to the aviation insurance marketplace that might affect either their current insurance program or their next renewal.

    See our recommended insurance agencies on our Aircraft Acquisitions page.

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