AcclaimML Posted November 15, 2012 Report Posted November 15, 2012 Had A successful 30 minute test flight last week. Just got back from 800+ mile round trip flight today. No oil consumption, cool temps, and serious speed-- without massive fuel consumption. The last 410 miles did in 1:39! Wow! 1 Quote
M016576 Posted November 15, 2012 Report Posted November 15, 2012 Had A successful 30 minute test flight last week. Just got back from 800+ mile round trip flight today. No oil consumption, cool temps, and serious speed-- without massive fuel consumption. The last 410 miles did in 1:39! Wow! Nice!!! Quote
AndyFromCB Posted November 15, 2012 Report Posted November 15, 2012 Congrats autopilots central fixed my autopilot today, looking forward to getting my bird back. Quote
Skywarrior Posted November 15, 2012 Report Posted November 15, 2012 Just curious, since my bird is a turbo... What is the physical reason for TIT being higher than EGTs? Quote
Nathan Peterson Posted November 15, 2012 Report Posted November 15, 2012 I'm glad all went well.. Enjoy! Quote
carqwik Posted November 15, 2012 Report Posted November 15, 2012 Nice...but it appears you're heading downhill with the rudder trim nearly all the way to the left. This may explain the high groundspeed! Quote
Steve Dawson Posted November 15, 2012 Report Posted November 15, 2012 Just curious, since my bird is a turbo... What is the physical reason for TIT being higher than EGTs? Check out Mike Busch's webinars. He's very discriptive on what EGT's refer too and what TIT is. Quote
BigTex Posted November 15, 2012 Report Posted November 15, 2012 Check out Mike Busch's webinars. If Mike received a kickback very time we pointed someone to one of his webinar's he'd be a very rich man! Quote
FBCK Posted November 15, 2012 Report Posted November 15, 2012 Thye TIT is higher as it is receiving exhaust from 6 cylinders and thus receivies a constant flow of gases, where an EGT and on and off and the valves open and close. Quote
KSMooniac Posted November 15, 2012 Report Posted November 15, 2012 Thye TIT is higher as it is receiving exhaust from 6 cylinders and thus receivies a constant flow of gases, where an EGT and on and off and the valves open and close. This is correct. The individual EGTs are only exposed to hot exhaust gas every 12 crank rotations for a 6 cylinder (I think that is right!) and the value you read is an averaged value over some time period that sees many of these pulses. The TIT is getting blasted by every cylinder and thus the averaged value is higher. Quote
AcclaimML Posted November 16, 2012 Author Report Posted November 16, 2012 Nice...but it appears you're heading downhill with the rudder trim nearly all the way to the left. This may explain the high groundspeed! Actually that's straight and level. I had a 20 knot cross wind component from the left. Check out fight aware on the overall flight if ya like. N730ML Quote
teckinger Posted November 21, 2012 Report Posted November 21, 2012 Actually that's straight and level. I had a 20 knot cross wind component from the left. Check out fight aware on the overall flight if ya like. N730ML Why would you need to have so much rudder trim for straight and level? Crosswind has nothing to do with this. Quote
AcclaimML Posted November 22, 2012 Author Report Posted November 22, 2012 Why would you need to have so much rudder trim for straight and level? Crosswind has nothing to do with this. Seriously? Did you not notice the 35 knot wind coming from my left? Spend a lot of time flying uncoordinated do ya? Quote
Marauder Posted November 23, 2012 Report Posted November 23, 2012 Seriously? Did you not notice the 35 knot wind coming from my left? Spend a lot of time flying uncoordinated do ya? Really? The only time I have seen that much rudder in straight & level flight was when my plane had a trailing flap. If your plane is rigged correctly, your would weather vane into the wind. Am I missing something here? Quote
AcclaimML Posted November 23, 2012 Author Report Posted November 23, 2012 Possibly. Maybe not. Starting to have some doubt here too, but my limited experience has been at high speed cruise an auto pilot will bank you into a cross wind to compensate for the sideways drift due to the lateral push of the crosswind on the entire airframe. I fact there is a lot more vertical cross sectional surface area of the cabin than the vertical stabilizer. This then results in an upward wing low, downward wing high, nose to the wind and a tail pointing down wind and an increased frontal area presented to the line of flight by the down wind side of the fuselage. Now you can fly like that if you want but it's not very efficient and definitely slower, plus not a big fan of going through the air sideways- or at least to the extent a high crosswind would impart. Rudder into the wind levels out the wings and minimizes this setup. Course you can see by the instrumentation that I was pointed into the crosswind. I just assumed the amount of rudder needed is a function of the true crosswind component and true airspeed. Which was 27 knots and 201 knots respectively. Somebody correct me if I'm wrong. I'm always looking to learn something new. Quote
carusoam Posted November 23, 2012 Report Posted November 23, 2012 AcclaimML, Are you sure??? Maybe I'm. Misunderstanding your statement... Are you saying... Your autopilot is making corrections for the cross winds while in cruise. The corrections include wing low into the wind and rudder input to balance the turning force generated by the lowered wing...? Aka slipping while cruising. Of course, you experience the extra control inputs are slowing you down a few knots. You have the most modern Mooney, so all things are possible...but, Even a 65C at the hands of a new pilot would handle a cross wind in cruise the same way as the most modern mooney with G1000 instruments, ya? They would both would fly straight and level and adjust the heading into the wind, no? Aka crabbing. Of course, for the strong cross wind that you have experienced, the correction would be quite large. A 25kt cross wind is about 13% the scale of a 200 kt cruise speed. But, no wing low and rudder being used in a continuous fashion, right? Or did I completely miss the boat on this one? Or is it possible the G1000 has determined a "better" way of handling cross winds? Maybe, such a strong cross wind is being controlled in an honestly strange fashion? My aged KAP150 simply points into the wind more, while keeping the plane on the Magenta line. Is the rudder actually active to coordinate turns that are being commanded by the AP? I would think so, because we have a motor driven rudder trim, but don't know for sure. Could be just the spring interconnections? It's good you brought this question out to better understand what the G1000 is thinking. As usual, I'm trying to help, but if I missed the boat, I don't want you to send a nastygram and quit using MooneySpace on my account...ya know? Let me know your thoughts. Best regards, -a- Quote
Marauder Posted November 23, 2012 Report Posted November 23, 2012 Possibly. Maybe not. Starting to have some doubt here too, but my limited experience has been at high speed cruise an auto pilot will bank you into a cross wind to compensate for the sideways drift due to the lateral push of the crosswind on the entire airframe. I fact there is a lot more vertical cross sectional surface area of the cabin than the vertical stabilizer. This then results in an upward wing low, downward wing high, nose to the wind and a tail pointing down wind and an increased frontal area presented to the line of flight by the down wind side of the fuselage. Now you can fly like that if you want but it's not very efficient and definitely slower, plus not a big fan of going through the air sideways- or at least to the extent a high crosswind would impart. Rudder into the wind levels out the wings and minimizes this setup. Course you can see by the instrumentation that I was pointed into the crosswind. I just assumed the amount of rudder needed is a function of the true crosswind component and true airspeed. Which was 27 knots and 201 knots respectively. Somebody correct me if I'm wrong. I'm always looking to learn something new. I would certainly like to hear others on the topic. I think I understand the concept you are presenting, but I'm not quite sure it works this way. I think the plane's natural tendency is to weathervane into the crosswind. Similar to what happens when you land into a crosswind. The only time I used rudder in straight and level flight was when I had a rigging problem and the "ball" was outside of the cage. Quote
Joe Zuffoletto Posted November 23, 2012 Report Posted November 23, 2012 AcclaimML, you might have a rigging problem. After I level off in my Acclaim, I let the plane accelerate to cruise speed, then I dial in my cruise power and mixture, then I adjust the rudder trim to the left until the TC on the G1000 shows I'm coordinated. Regardless of the crosswind component, the rudder trim is always at dead center or very close in coordinated flight. Just last week I flew from Albuquerque to Denver in the flight levels with a 65-knot crosswind from the left. Rudder trim was dead center in coordinated flight. In fact, when I was first getting checked out in the plane, one time my flight instructor and I were cruising along on autopilot and couldn't figure out why we were consistently flying right of course. Turned out I forgot to neutralize the rudder trim once I leveled off. The autopilot was fighting the full right rudder deflection and losing. Quote
DonMuncy Posted November 23, 2012 Report Posted November 23, 2012 My understanding is, in cruise, there is no "wind pushing the airplane". When moving in a stable air mass (no shear problems), your plane, and its avionics do not know there is a wind. It just flies a heading to get where it wants to go. There should be no wing low or rudder inputs. Am I wrong? Quote
aviatoreb Posted November 23, 2012 Report Posted November 23, 2012 My understanding is, in cruise, there is no "wind pushing the airplane". When moving in a stable air mass (no shear problems), your plane, and its avionics do not know there is a wind. It just flies a heading to get where it wants to go. There should be no wing low or rudder inputs. Am I wrong? That's right - with a wind cross to your cruise flight path - you (or your autopilot) just establish a crab angle nose partly into the wind - but with neutral rudder and ailerons - your airplane thinks it is flying straight. It is - only the air is moving under it so your ground track is different from the direction your nose is pointing. But if you want your nose direction and ground track to match despite ground track then you would need to cross control as you do in cross wind landing - ailerons to dip a wing into the wind and opposite rudder - but don't do that in cruise since there is no need and it introduces unesc drag. Quote
carusoam Posted November 23, 2012 Report Posted November 23, 2012 Where does the rudder trim indicate on the g1000? I was looking to see if it was left in or out, but don't see it. Or do you have the independent LED indicators of the older long bodies? If you leave the right rudder correction in from take-off, the AP will probably fight the excess rudder with left aeleron. No matter which direction the relative wind is blowing. -a- Quote
AcclaimML Posted November 24, 2012 Author Report Posted November 24, 2012 AcclaimML, you might have a rigging problem. After I level off in my Acclaim, I let the plane accelerate to cruise speed, then I dial in my cruise power and mixture, then I adjust the rudder trim to the left until the TC on the G1000 shows I'm coordinated. Regardless of the crosswind component, the rudder trim is always at dead center or very close in coordinated flight. Just last week I flew from Albuquerque to Denver in the flight levels with a 65-knot crosswind from the left. Rudder trim was dead center in coordinated flight. In fact, when I was first getting checked out in the plane, one time my flight instructor and I were cruising along on autopilot and couldn't figure out why we were consistently flying right of course. Turned out I forgot to neutralize the rudder trim once I leveled off. The autopilot was fighting the full right rudder deflection and losing. Maybe I do have a rigging problem. But I do exactly as you describe above. But the only time I've ever not had at least some rudder either left or right was when I had negligible cross winds either way during a high speed cruise. . On the day I described initially , was actually two flights in opposite directions in similar conditions. I has some right rudder on the first leg but was flying slower and had only a 10 knot crosswind. Then as folks have pointed out I had a lot of left rudder on returning. But I didn't think too much about it as this was the highest, fastest I've flown the Acclaim and in those types of winds. Maybe I'm doing something wrong but I see the same behavior in the TC Saratoga and the DA40. Oh heck. I guess I'll just have to take her up and check her out! While I'm at it ill get the rigging checked too. Starting to get a complex guys Quote
AcclaimML Posted November 24, 2012 Author Report Posted November 24, 2012 Where does the rudder trim indicate on the g1000? I was looking to see if it was left in or out, but don't see it. Or do you have the independent LED indicators of the older long bodies? If you leave the right rudder correction in from take-off, the AP will probably fight the excess rudder with left aeleron. No matter which direction the relative wind is blowing. -a- Image one shows the rudder trim on the engine page at the bottom pitch on the right edge with the small blue arrows. The image on the right is the pfd notice the nose is into the wind wings level. And to those who asked the rudder is motorized but not tied to the GFC auto pilot. Now I guess there maybe some inaccuracy with the digital representation on the G1000. But I was definitely faster coordinated with the rudder trim. Will find out tomorrow. Quote
AcclaimML Posted November 24, 2012 Author Report Posted November 24, 2012 That's right - with a wind cross to your cruise flight path - you (or your autopilot) just establish a crab angle nose partly into the wind - but with neutral rudder and ailerons - your airplane thinks it is flying straight. It is - only the air is moving under it so your ground track is different from the direction your nose is pointing. But if you want your nose direction and ground track to match despite ground track then you would need to cross control as you do in cross wind landing - ailerons to dip a wing into the wind and opposite rudder - but don't do that in cruise since there is no need and it introduces unesc drag. Exactly. Except no crab here just some same side rudder obviating any aileron to the same side. Quote
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