gbigs Posted March 21, 2015 Report Share Posted March 21, 2015 This whole conversation reminds me of a story, about a mother watching her son in the local marching band as they went by in the town parade. Beaming with pride, the mother remarked: "It's appalling that *every* one of the band members is out of step, except my son!" You may want to get in a new CTLSi and observe and test the newest technology before making assumptions. The older planes (2K, SW) are nothing like the new ones, especially if equipped with steam gauges and no autopilot as compared to the (CT, CTLSi), especially if equipped with Dynon Skyviews, Dynon Autopilot and the Garmin 796 GPS. FD knows this and sometimes regrets the 'mistakes' they made in the older planes. But the company continues to evolove the products - like adding the Dynon touch to the newest incarnation. Sadly, we all do own Flight Designs but only a few of us have the new planes and know how advanced they are over the older ones. This autopilot discussion is just one more example of that fact. Link to comment Share on other sites More sharing options...
FastEddieB Posted March 21, 2015 Report Share Posted March 21, 2015 This autopilot discussion is just one more example of that fact. No, its not. There's no existing technology that will center the ball and coordinate flight without connecting to the rudder in some fashion. Some Cirrus' do. Many bigger planes do. It's called a yaw damper and is, in fact, pretty sophisticated. I don't think your CT has one, but if it does I've learned something and I stand corrected! Link to comment Share on other sites More sharing options...
FlyingMonkey Posted March 22, 2015 Report Share Posted March 22, 2015 Sadly, we all do own Flight Designs but only a few of us have the new planes and know how advanced they are over the older ones. This autopilot discussion is just one more example of that fact. You are right. The older airplanes are only equipped with a two axis GPS-slaved autopilot with a digital control system that can monitor and adjust both heading and altitude. Oh wait...that is the same type system you have. Link to comment Share on other sites More sharing options...
Duane Jefts Posted March 22, 2015 Report Share Posted March 22, 2015 The CTLSi does not have a yaw damper. Link to comment Share on other sites More sharing options...
WmInce Posted March 22, 2015 Report Share Posted March 22, 2015 Why would your autopilot want nose down trim in a strong headwind? That makes no sense. The dude still doesn't understand fundamentals of flight. He also has no clue on how his autopilot functions. Link to comment Share on other sites More sharing options...
gbigs Posted March 22, 2015 Report Share Posted March 22, 2015 The CTLSi does not have a yaw damper. Do you have the Dynon autopilot? If so, does your ball stay centered when you have it active? Link to comment Share on other sites More sharing options...
DoctorJohn Posted March 22, 2015 Report Share Posted March 22, 2015 This thread is comical...but sad. Link to comment Share on other sites More sharing options...
Doug G. Posted March 22, 2015 Report Share Posted March 22, 2015 Remember Einstein's definition of insanity? This experiment has gone on for a couple of years with the same results. You can't educate a person who knows everything, they just aren't open to it. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 22, 2015 Report Share Posted March 22, 2015 Tru Trak has a yaw damper for $725 The Yaw Damper employs a solid state rate gyro to damp out short term yaw oscillation, and a transverse accelerometer to control rudder position long term, so as to keep the ball centered. The Yaw Damper can be added to the DFC-200 or Sorcerer autopilots. • 2.05" H x 4.12" W x 1.69" D • 12-28 volts • Standard Weight including servo 3.25lb http://www.pilotshop.com/catalog/avpages/trutrakYawDamper.php?gclid=CjwKEAjw0LmoBRDHuo7UkaKXhn8SJADmDTG0loQqSuPBHlKxDH6AqGFVgpG-zN5Qty3-N1QRJH_1ohoCcEHw_wcB Link to comment Share on other sites More sharing options...
FastEddieB Posted March 22, 2015 Report Share Posted March 22, 2015 That is pretty cool! With that you'd virtually never have to touch any of the controls. Pure flying bliss! Link to comment Share on other sites More sharing options...
Duane Jefts Posted March 22, 2015 Report Share Posted March 22, 2015 Do you have the Dynon autopilot? If so, does your ball stay centered when you have it active? Cecil - Yes on the Dynon autopilot. It does not center the ball in an "out of center" condition. You should give up on this topic. Link to comment Share on other sites More sharing options...
gbigs Posted March 22, 2015 Report Share Posted March 22, 2015 Cecil - Yes on the Dynon autopilot. It does not center the ball in an "out of center" condition. You should give up on this topic. This topic is not mine, it's others who are not flying the autopilot. Your comment is not clear. If the ball is out on my plane when I click on the autopilot, the autopilot corrects and coordinates the flight and centers the ball and keeps it there. Are you saying you do not see that in your plane? Mr. Jefts. I believe this is important enough to settle because I believe this is a strong feature and capability of the new Flight Design's. Potential new customers should be made aware that this tool is in the plane. And i am sure Flight Design and Dynon will want potential customers to know it too... Link to comment Share on other sites More sharing options...
FastEddieB Posted March 22, 2015 Report Share Posted March 22, 2015 If the ball is out on my plane when I click on the autopilot, the autopilot corrects and coordinates the flight and centers the ball and keeps it there. Again, it really, truly and honestly doesn't. It can't without a connection to the rudder, which its been verified your plane does not have. In your primary training, how were you taught to keep the ball centered? If like most (all?) students, it would have been with your feet, applying input to the rudder. A two-axis autopilot can only control roll and pitch - not yaw. And it's yaw that centers the ball. There's no need for you to be wedded to a flawed understanding of how a two-axis autopilot works, and then defend that misunderstanding to the death. It's perfectly fine for you to absorb new information, and to reconsider a position based on that new information. Lord knows I've done that enough times! And its great, because its called "learning". A simple, "Oh, I see what you mean. Let me rethink what's going on!" would be a good place to start. Link to comment Share on other sites More sharing options...
Jim Meade Posted March 22, 2015 Report Share Posted March 22, 2015 In your primary training, how were you taught to keep the ball centered? If like most (all?) students, it would have been with your feet, applying input to the rudder. A two-axis autopilot can only control roll and pitch - not yaw. And it's yaw that centers the ball.As you point out, most of us are taught and teach to center the ball by using the rudder. It is, of course, possible to center the ball by using the ailerons. It's interesting to roll into about a 15-20° bank, deliberately put the ball slightly out of center, and center it with the stick. Of course, this changes the direction you are flying and is not really on topic of this thread, but it is a fact that you can put the ball in the middle with the stick as long as you know it will change whatever turn rate you have established. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 22, 2015 Report Share Posted March 22, 2015 As you point out, most of us are taught and teach to center the ball by using the rudder. It is, of course, possible to center the ball by using the ailerons. It's interesting to roll into about a 15-20° bank, deliberately put the ball slightly out of center, and center it with the stick. Of course, this changes the direction you are flying and is not really on topic of this thread, but it is a fact that you can put the ball in the middle with the stick as long as you know it will change whatever turn rate you have established. I was thinking similarly but there is a snag. Code could be written to coordinate with the flaperons but coordinate with what? There is no rudder servo so you can't initiate with rudder and coordinate with flapperons either way you need a 3rd servo to move the rudder. Link to comment Share on other sites More sharing options...
Jim Meade Posted March 22, 2015 Report Share Posted March 22, 2015 CT, I said this post was a non-sequitor. I'm not talking about an auto-pilot application. Just go out and hand fly it and see that it works that way. My only point was that one can center the ball with the aileron as well as with the rudder. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 22, 2015 Report Share Posted March 22, 2015 CT, I said this post was a non-sequitor. I'm not talking about an auto-pilot application. Just go out and hand fly it and see that it works that way. My only point was that one can center the ball with the aileron as well as with the rudder. The fact that we can and do center the ball with flaperon input shows the flaw in arguing that burger's Dynon couldn't center the ball because its not hooked up to the rudder. Once I realized that his Dynon with some creative code could in fact center his ball I thought for a minute that it could be done and truly it could but without any rudder input the approach would be a bizarre combination of flaperon vs flaperon. The better argument is that 3-axis control is required for coordination. Link to comment Share on other sites More sharing options...
FastEddieB Posted March 22, 2015 Report Share Posted March 22, 2015 Early on I stipulated that good aileron design can center the ball in some phases of flight. That does not alter the flight that its not the autopilot actively doing it, which is the allegation. Link to comment Share on other sites More sharing options...
FastEddieB Posted March 22, 2015 Report Share Posted March 22, 2015 Back to Jim's point, a slip or skid can be defined as either too much or too little bank for a given rate of turn. So one way to bring the ball back into the center would be to maintain the same rate of turn but to alter the bank to be appropriate for the rate. This is rather than altering the rate to be appropriate to the bank, which is what we do when we apply rudder. But I still hold that the autopilot would need rudder authority to keep things "appropriate". Link to comment Share on other sites More sharing options...
FastEddieB Posted March 22, 2015 Report Share Posted March 22, 2015 Perhaps worth mentioning is that once established in a medium turn, no aileron needs to be held. Hence, no rudder is needed, and in a properly rigged plane the ball will stay in the center on its own. All that's needed is back pressure. Adverse yaw requiring rudder is generally only apparent when rolling into and out of turns, and if that's gradual enough and the ailerons are well designed, no rudder may be needed through the entire process. But its STILL not the autopilot coordinating the turn. Link to comment Share on other sites More sharing options...
DoctorJohn Posted March 23, 2015 Report Share Posted March 23, 2015 If an airplane is flying straight and level in uncoordinated flight, the ball will be off center. This can be corrected by "stepping on the ball" to eliminate a slipping or skidding situation. Another way to eliminate the slip or skid and center the ball is to bank the airplane to create a coordinated turn. I've never seen or heard of an autopilot that is programmed to keep the ball centered by turning willy, nilly left or right with the objective to hold altitude and coordinated flight, but fly a random heading or course. A pilot or autopilot needs rudder control, in addition to aileron and elevator, to maintain coordinated flight and fly a desired heading or course. These basic theories of flight have not changed with the introduction of the Flight Design CTLSi or a glass cockpit or a Dynon system, etc. Link to comment Share on other sites More sharing options...
Jim Meade Posted March 23, 2015 Report Share Posted March 23, 2015 Adverse yaw requiring rudder is generally only apparent when rolling into and out of turns, and if that's gradual enough and the ailerons are well designed, no rudder may be needed through the entire process. My experience with the CTSW is that rolling into a level turn, one needs to lead with a little aileron - very little - and then come in with rudder, maybe a lot of rudder depending on the bank. Most of the turn can be done with the rudder. The steeper the bank, the more rudder. Today, I went out and tried to fly coordinated level turns with no reference to the ball. A co-pilot watched the ball while my gauges were covered. One can fly a level turn by the seat of the pants, but it takes some iterations and development of some muscle memory to keep the ball centered without looking at it. Link to comment Share on other sites More sharing options...
FastEddieB Posted March 23, 2015 Report Share Posted March 23, 2015 Thanks for the info. Planes do vary a lot in their need for rudder to stay coordinated. A Bonanza or a Cirrus - or a CT - may need very, very little. Coordinated shallow to medium turns in the first two can almost be done feet-on-the-floor. A Cub or Citabria or my Sky Arrow not so much. They require rather fancy footwork to achieve the same end. Pilots transitioning back to those types may need to learn to wake up their feet! Link to comment Share on other sites More sharing options...
Tom Baker Posted March 23, 2015 Report Share Posted March 23, 2015 The CT needs more rudder changes related to power changes than any small low powered airplane I have flown. It takes quite a bit of right rudder for take off and climb. It takes quite a bit of left rudder when you reduce the power. I have seen the nose swing right up to 20° when power was reduced without applying rudder. As for Jim's statement on leading with ailerons and then more rudder, I think it depends on what you are doing in flight. With power off in the pattern it is very much a lead with rudder plane, because if you move the stick first the nose will swing the opposite way. It has a bunch of adverse yaw when slow with flaps extended. I tell students a quiet stick on final makes for a happy airplane, because most can't keep up with rudder if the are using to much aileron. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 23, 2015 Report Share Posted March 23, 2015 The CTSW is quite short coupled and rudder dominant. The CTLS is a stretched SW and exhibits less yaw, adverse and otherwise. Link to comment Share on other sites More sharing options...
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