I just tried a quick flight with the mod and I agree that the pedals don’t seem to do much. Haven’t tried the ACFCS yet. Hopefully tomorrow.
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It’s less responsive than it was, but I managed to repeat maneuvers from RAF flight display, so it should at least be generally in the same envelope as the real one. Configuration is a bit of a balance between twitchy at low speed and maneuverable at high speed.
Since this is at least the second time I see this potential misunderstanding, let me point one thing out.
NORMALLY AFCS IS ENABLED AT ALL TIMES. I understand there might be some confusion, the developers originally used the acronym for autopilot functions, because so called upper modes de facto perform autopilot functions. I see how that might suggest you might not want to use it for normal hand flying.
But.
In heavy lift helicopters you fly with AFCS ON, period. If you’re not using it, you’re either IN an emergency or practicing for an emergency, or doing some crazy airshow stunts, and you better know what you’re doing. All normal ops are flown with AFCS ON. It’s not something you turn on optionally when you want to doze off. It’s how you fly that bird, period.
Q: My joystick in virtual cockpit wobbles with AFCS ON
A: Yes, that’s normal. The system moves your controls as it’s supposed to. It probably doesn’t feed back such shakes to the control handle in real life, that’s a sim limitation. But moving your control surfaces to maintain normal attitudes is exactly what it’s supposed to do
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Ah. Okay. That makes sense. Although with other helos there is a Force Trim Release button which allows the pilot to intervene and provide inputs and change the a/c attitude. Is there such a button in the CH47?
Actually yes. Bind AUTOPILOT ATTITUDE HOLD OFF to your button of choice as “ON PRESS” and AUTOPILOT ATTITUDE HOLD ON to that same button, but “ON RELEASE”.
The code will send your new attitude to the system upon release. Until you release the button the system will not interfere with your inputs
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Thanks. I will try that.
Look like there is a flight model problem when the aircraft is fully loaded.
While trying to keep altitude with control fully trimmed, and Baro ALT set, the aircraft will become unstable and dive unexpectedly for no reason, that never happen when flying without load, only happens under full load scenarios, have not tried with a hanging load.
Has anyone else experienced a similar situations?
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I think it might be power deficiency, I’ve noticed that previously. Look at rotor RPM. Power tuning is still WIP, it pulled off MTOW in ground effect, but out of it might be a problem, I’ll rework it with the chart soon. Added to known issues, I’ll let you know when it’s fixed
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Is this using DinoPete’s FM Mod, or the default FM?
If it occurs using the default FM please create a ticket here: Contact
Can’t provide support here as per the forum rules
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Maybe the Asobo double rotor isn´t perfect either and the problem is there?, another double rotor in MSFS there isn´t, I think, or work together with them if possible?, no idea.
The tandem rotor implementation on MSFS is, at least IMO, far from perfect and nearly unusable unless you have active stabilization (SAS) - hence why we decided to support @DinoPete11’s mod. The undesired inertial reactions as a result of pitch and yaw with the tandem FM are totally inaccurate for the CH47D. I’m actually just working on a forum post explaining it all to clarify the situation.
The active stabilization, at least at this stage, isn’t feasible to make it to production for various reasons (mainly the “flickering” on the controls due to the SAS system taking over, potential instabilities on the FM caused by this system leading to customer dissatisfaction, and particularly concerns regarding Xbox performance - active SAS has never made it to Xbox so far).
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Is it possible disable SAS to test?
In the mod SAS can be toggled, and the default is OFF at the moment. See the file in DOCUMENTATION folder
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Tandem rotor system is much more complex than just the fact that they counter rotate.
Nose pitch in CH47D is controlled by differential collective. Nose down is achieved by front rotor collective down and rear rotor collective up. Collective up increases torque, torque up increases yaw drift. One rotor produces more yaw than the other when you push or pull cyclic.
Cyclic pitch also increases or decreases disc loading. Lateral cyclic will change disc loading equally when you’re flying perfectly into relative wind. With crosswind it will once again not be so nice and equal. In that case once again, different disc loading = different torque = different yaw.
It’s not Asobo mishap as far I have seen so far. It’s just physics.
Chinook flies in such a stable and consistent manner because its balance of weights and forces was very carefully engineered for it, and only in conjunction with complex digital AFCS / stability assist. This goes down to the point that full capacity of fuel tanks is asymmetric between left and right side. The reality is NOT tandem rotors = no yaw. Chinook does not fly straight hands off without a computer making it happen, it never did.
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Awesome info highlighting perfectly the intertwined complexities involved when dealing with physics and the problems in getting it to behave in our pretend aircraft. 
Amazing that they can overcome this in the real world and have a computer making sure all those pilots and their passengers are safe, while making it look effortless — as if nothing is really happening.
Good luck taming it!! Sounds like a bit of a nightmare!
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I like a challenge, and freeware modification means we can freely experiment until it’s really, really good, without being responsible for people’s purchase money. There may be some regressions along the way but we’ll get there. Maybe more tools appear that will allow for better force trim for example
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Thanks for your feedback - however, I respectfully disagree.
The thing here is (and you can see plenty of discussion above) - the flight model has been designed to fly like a CH47 with the SAS System on. The current flight model does behave as such within the limitations of simulation: Pedals on the CH47 provide a yaw-only movement as the flight computers will provide the necessary input to keep the helicopter in a stable position, the cyclic will provide pitch and roll movements only as the computer will respond to the other undesired intertial reactions and account for them (and has been validated by at least two CH47 Pilots) - that being said, DinoPete has a very interesting opinion on pilot feel and MSFS FMs, which is worth a read: Cerasim Mi17 - #257 by DinoPete11
Ultimately we must cater to the largest audience possible - and the general opinion talks for itself. It is unfeasible to change a flight model when satisfaction is >90%
I’ve explained everything in detail on my forum post here: On the topic of CH47D, Tandem Flight Models and SU15...
Edit: The following document in theory of operations of the CH47 does corroborate that the flight model is correct in the 3 main axes: https://www.chinook-helicopter.com/Publications/Theory_Of_Operation/CH-47_Theory_of_Operations.pdf
As you can see pedal provides yaw only, cyclic provides roll/pitch only. Combination of yaw+roll is required to perform coordinated turns.
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Hey there. Hopefully you can give this one some time and maybe get used to how it flies. There are a whole lot of helicopter sim enthusiasts like myself that are very pleased with the flight model and how it mimics the CH-47. Hopefully you can get to the point where you don’t feel like you have wasted your money. Cheers.
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Hi,
I’m one of the players that enjoy the CH-47 for what it is, within the current limitations of MSFS. Although it doesn’t behave like a traditional helicopter with a tail rotor, I didn’t expect it either.
And I was born on a USAF base, did military service in the USAF, and have been close to military and civilian aircraft my entire life.
I still wouldn’t really be able to tell someone how any specific airframe should actually behave. Overall, I still give your CH-47 high marks 
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I wish you had it on PC, I understand your concerns, I started work on the mod because I share at least some of them. There’s limits to what Miltech can do with a fully XBOX compatible product, but I’m working to push them further, and I do get meaningful support from Miltech devs.
I hope eventually modification will reach a point that will bring a realistic experience to xbox as well, not just in terms of general result, but also in principles of operation. Sadly mod is not there yet. At the very least, I hope we can research stuff that will help future releases built from the ground up with more sophisticated FM and systems.
Current Chinook was built under the assumption that accurate AFCS is impossible in MSFS. In the meantime, with some out of the box experimentation I have discovered that’s not entirely true (and obviously you have HPG demonstrating it can be done in a PC only addon). We’re trying to rebuild chinook for that but it’s WIP. I wish we could use you for testing, maybe one day it’s official and you as an Xbox user can see it fly to Your satisfaction
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I have the 47 on PC and I can turn well with the cyclic. It doesn’t fly like other helicopters because it’s not like other helicopters. I have full helicopter flight controls also so that may be the ticket. Not sure how it flys on a gaming console with a game pad. I think Miltech has done a pretty good job on this aircraft.
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