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Christopher Low

J41 pulling to the right

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I finally managed to remove the passengers from the cabin, but now I have a new problem. The plane keeps pulling to the right. I assume that this has something to do with the CG, but I am not sure how to correct it. I thought that it would have been central to the longitudinal axis of the plane with only pilot and copilot on board (and 50% fuel in each tank), but that doesn't seem to be the case. When I add slightly more fuel on one side (to get the CG centralised), the plane pulls even more to the right!


Christopher Low

UK2000 Beta Tester

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Guest BlueRidgeDx

What do you mean by "pulls to the right"? During taxi? Rolling to the right in-flight? Yawing right while in-flight? Are you using hardware throttles? I used a Saitek throttle quadrant throughout beta testing, and it was quite a bit of work to match torque. could that be the problem?Otherwise, it sounds like a simple controller calibration or toe brake problem.Regards,Nick

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Chris, why do you suspect lateral cg imbalance?Is the plane pulling to the right on taxi or flight conditions? Did you rule out crosswind?


Dan Downs KCRP

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Christopher,Do you mean ROLLING to the right? If so, check your joystick calibration.


Best Regards,

Kurt "Yoda" Kalbfleisch

Pinner, Middx, UK

Beta tester for PMDG J41, NGX, and GFO, Flight1 Super King Air B200, Flight1 Cessna Citation Mustang, Flight1 Cessna 182, Flight1 Cessna 177B, Aeroworx B200

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Dan,Sorry for being a nuisance, but it was taking off (and flying) nice and straight before I removed the passengers. I am using the same start conditions (weather, airport, runway) for each test, and the default Baron takes off and flies perfectly level under the same conditions. Therefore, the problem must be due to something other than a joystick calibration problem. The plane is pulling to the right on the runway during the take off run, and then starts to pull away to the right after getting airborne.The CG position on the small airplane diagram in the FSX "Fuel and Payload" section appears to be slightly over to the left with 50% fuel in each tank, plus the pilot and copilot.


Christopher Low

UK2000 Beta Tester

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Christopher,You're not being a nuisance!Are you starting from a saved situation or from Free Flight directly into the J41? I'm asking because I wonder if you're not getting both engines off the start latches. Do you get full power on both engines during the takeoff roll?


Best Regards,

Kurt "Yoda" Kalbfleisch

Pinner, Middx, UK

Beta tester for PMDG J41, NGX, and GFO, Flight1 Super King Air B200, Flight1 Cessna Citation Mustang, Flight1 Cessna 182, Flight1 Cessna 177B, Aeroworx B200

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That symbol slightly off center shouldn't be significant. I weight 180 and the plane owner is the size of a linebacker but just the two of us in the Chancellor has no bearing.Try the takeoff with weather set to clear (clears all weather) just to humor me.Verify the trims (roll and rudder) are centered, and control is calibrated.Edit: Kurt got in before me and he has a great point. By full power, he means look at the Torque indicators.


Dan Downs KCRP

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Kurt,You make an interesting point about not getting both engines off the start latches. The plane seems to be taking longer to get airborne than it was with passengers in the cabin. I know that removing them has moved the CG forwards, but the reduced weight should surely get it airborne more quickly? If so, then maybe I am not getting full power from both engines? I will check that out, and report back.Another point worth noting is that the engines are blowing on a regular basis at the moment, which is also something that wasn't happening earlier. I am starting from the runway threshold with both engines running, so I assumed that everything would be set for the take off run (apart from flaps). It certainly seemed to work at first.......


Christopher Low

UK2000 Beta Tester

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Kurt,You make an interesting point about not getting both engines off the start latches. The plane seems to be taking longer to get airborne than it was with passengers in the cabin. I know that removing them has moved the CG forwards, but the reduced weight should surely get it airborne more quickly? If so, then maybe I am not getting full power from both engines? I will check that out, and report back.Another point worth noting is that the engines are blowing on a regular basis at the moment, which is also something that wasn't happening earlier. I am starting from the runway threshold with both engines running, so I assumed that everything would be set for the take off run (apart from flaps). It certainly seemed to work at first.......
I got my first flight in the air for a little sight seeing and pattern work. I found that that airplane wants to roll over pretty easily. I was running ASA, so I will try again without it, but the tendency was to roll right...but a few times it would roll to the left as well.Very strange. I'll test without ASA and report back...Thanks!

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I was using a saved situation for these test flights, so I decided to set it up from scratch. This time, the J41 stayed aligned with the runway centreline, and it remained level after becoming airborne. Presumably, there is some issue with saved situations? I hope that doesn't affect my test flights, because it's easier to load up a saved flight with all of the parameters set (seat position, no passengers, flaps etc). I have saved this one now, so I will have to check if it still works properly the next time that it is loaded!To be honest, I am still trying to work out the best trim position, degree of flaps etc. for my style of flying. It might be a difficult task, but I would like to be able to nail it if I can :(EDIT: I thought you might like to see a nice shot of the J41 in action :(


Christopher Low

UK2000 Beta Tester

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Lol, I've done that a few times myself. However, once you get used to the little quirks with the engines, they are pretty easy to handle.

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Nameless-Please start signing your name inside your posts- or one of our many forum mods will simply remove the thread because it doesn't comply with forum guidelines, thanks!)A couple of things to point out here:1) CG of an empty airplane will not cause the airplane to pull right.2) Trim position should be Roll: 0, Yaw: 0, Pitch: In the green band. (Generally centered.)Now- as Dan suspected- i'm guessing you have not made any effort to ensure that your props are off the start locks before attempting takeoff roll. This start-lock check should be habitual... Just pull each power lever into reverse briefly before each takeoff... If you are NOT off the startlocks- you will have a significant reduction in thrust available, (Tq will tend to stop increasing at 30%) and the airplane will yaw toward the "still locked engine" You will discover that you need to be mindful of the EGT on these engines... Attempting a start when EGT is over 200C is a recipe for disaster... Running the power up with an engine on the start locks is a recipe for disaster... Our best advice- is to spend time in the tutorial- making sure you read through the engine portion. Once you get the procedures down- the engine are very easy to manage- but if you try to skip that part of the education process you'll have nothing but frustration!


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PLEASE NOTE THAT PMDG HAS DEPARTED AVSIM

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Hmmm...That shot looks familiar....O that's right, I did that a couple times myself last night!Now though, I am working my way through the tutorial flight...slowly that is.

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Hmmm...That shot looks familiar....O that's right, I did that a couple times myself last night!
Like a gear up landing: Only two kinds of pilots in this regard, those have have and those that haven't yet.

Dan Downs KCRP

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Our best advice- is to spend time in the tutorial- making sure you read through the engine portion.
Yes, I intend to take a look at that tutorial. I was just testing the plane from a "standing start at the threshold with engines running" scenario. Since the help from Dan and Kurt, I have managed to successfully take off and fly around without the engines exploding! Mind you, I was quite impressed with the flames and smoke when it happened. That's why I took a screenshot :(

Christopher Low

UK2000 Beta Tester

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