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MU-2 Elevator Trim Tabs

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Hi everybody,

 

There seems to be an animation issue concerning the MU-2 elevator trim tabs. As for inflight trimming purposes, a Trim Tab is actually required to move in the opposite direction to that of the control surface it is connected to for trimming.

So, in Flysimware's MU-2, for an inflight Nose-Up trimming, Tabs are incorrectly modelled moving upward -when they must move downward to force elevators upward and hence lower the aircraft's tail resulting in a nose-up attitude. Logically enough ...for trimming Nose-Down... just the opposite is observed.  In case of disagreement, then it can be easily verified just observing another quality product... or real life aircraft !

 

Cheers,

Carlos

 

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Trim tabs can be servo (adding to the force vector) or anti-servo (diminishing the force vector) and can function in more than one way, so you should be careful about such sweeping generalisations. Perhaps you could provide reference material to qualify your assertion for the MU-2 ?

 

As the Moo uses a conventional tailplane and elevator arrangement, located aft of the MAC, I suspect that the wide range of operating airspeeds for the aircraft may require an anti-servo system. Remember, on a conventional platform the tailplane exerts a downforce vector, not a lift force. One that progressively increases with airspeed. The effect of which is to create an increasing nose-UP moment that is compensated for by pushing the yoke forward - and the elevator down. Trimming the force out of that movement suggests anti-servo effect - up movement on the trim tab.  

The trim tabs on the elevator on the MU2 have a range of +30/-1 degrees operation, confirming that more tab `up` is applied than tab `down`. This would suggest that either Mitsubishi got this wrong, or you did. I don't think there's any animation issue, but please do cite your sources and let's have a look.

 

I doubt you will get any response from the developers. They seem to have gone off the idea of interacting with the customer base, save for promoting their next unfinished product. The Moo is about as good as its going to get so even if you are right, I wouldn't expect a model recompile is even remotely likely.

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I doubt you will get any response from the developers. They seem to have gone off the idea of interacting with the customer base, save for promoting their next unfinished product. The Moo is about as good as its going to get so even if you are right, I wouldn't expect a model recompile is even remotely likely.


 

Yup the Animation is way off, if you look you will see it's all the way up  and looks very Unrealistic, the auto pilot is off as well. Basically you get what you Get because they have a new and exciting

Lear jet coming out and can't be bothered finishing the Moo.  Good Luck .

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Trim tabs can be servo (adding to the force vector) or anti-servo (diminishing the force vector) and can function in more than one way, so you should be careful about such sweeping generalisations. Perhaps you could provide reference material to qualify your assertion for the MU-2 ?

 

As the Moo uses a conventional tailplane and elevator arrangement, located aft of the MAC, I suspect that the wide range of operating airspeeds for the aircraft may require an anti-servo system. Remember, on a conventional platform the tailplane exerts a downforce vector, not a lift force. One that progressively increases with airspeed. The effect of which is to create an increasing nose-UP moment that is compensated for by pushing the yoke forward - and the elevator down. Trimming the force out of that movement suggests anti-servo effect - up movement on the trim tab.  

The trim tabs on the elevator on the MU2 have a range of +30/-1 degrees operation, confirming that more tab `up` is applied than tab `down`. This would suggest that either Mitsubishi got this wrong, or you did. I don't think there's any animation issue, but please do cite your sources and let's have a look.

 

I doubt you will get any response from the developers. They seem to have gone off the idea of interacting with the customer base, save for promoting their next unfinished product. The Moo is about as good as its going to get so even if you are right, I wouldn't expect a model recompile is even remotely likely.

You asked me for my sources of information. I think you got these both sources, the MU-2B-60 Marquise Aircraft Flight Manual I had mentioned already in the other post, and the FAA’s corresponding Aircraft Type Certificate I cite now.

 

As an elemental comment, being it the Mitsubishi or another aircraft with the same conventional design:  I cannot think of any way for Trimming Nose Up, having a Nose-Up indication from the Elevator Trim Indicator, and getting out of the aircraft just to find out that the elevator Trim Tabs are pointing UP! … no way I would takeoff… what I would take is a photograph for sure… and what ever actions would be in order!

 

Once said that, I consider unnecessary all what follows, but anyway here it comes:

 

This is textual Information regarding Elevator Trim Tab under “control surface movements” paragraph as directly taken from the FAA corresponding Aircraft Type Certificate:

 

“Elevator Tab Nose Up 30° Nose Down 1° (See Note 8)”

 

“NOTE 8. Airworthiness Directive– AD 93-07-11, mandated that the maximum deflection of the elevator nose-down trim reduced to 1 degree from 10 degrees in accordance with Mitsubishi Heavy Industries LTD. Service Bulletin No. 079/27-010 dated August 28, 1992. Effected models are MU-2B-25/-26/-26A/-40/-35/-36/-36A/-60”.

 

So, if reading carefully this Acft. Type Cert.:  “Elevator Tab Nose Up 30° ” is exactly the opposite to what you state as “ +30/-1 degrees operation”  “more tab `up` is applied than tab `down` “.

 

Type Certificate reads “Elevator Tab Nose Up 30° ” ... I repeat: “Nose Up”  ... NOT Tab Up 30º or +30 deg. as you state.

 

Type certificate specifying “Elevator Tab Nose Up 30° ”  implies that for the aircraft Nose Up attitude, the Trim Tab will have a 30º range DOWN in relation to the elevator …in order to force the elevator UP and thus achieving a Tail Low/Nose Up attitude.

 

I would’nt like to take this argumentation any further. You may be perfectly sure about your point of view and adhere to it…. I adhere to mine.

Cheers,

Carlos

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Both the ELEVATOR trim tab as well as the RUDDER trim tab animations are the opposite of what they should be. Hopefully this will be fixed.

 

tab1.jpg

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louisdecoolste, on 19 Aug 2015 - 04:22 AM, said:


I doubt you will get any response from the developers. They seem to have gone off the idea of interacting with the customer base, save for promoting their next unfinished product. The Moo is about as good as its going to get so even if you are right, I wouldn't expect a model recompile is even remotely likely.


 

We have not in anyway abandoned the customers, or our attention to the forums. However, the person who is typically the one responsible for addressing concerns posted here has gotten rather busy with his life away from the sim world. I am merely on the Beta Team, but I try to check the forums on a regular basis, and will bring this up to Mark. It may not get addressed right away, but it has been noted.

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Excellent news. Perhaps a little less time pimping their new build jet in FaceAche and a bit more time here in their Official Support Forum dealing with paid customers ? They managed to update that only a day or so ago.

 

An explanation as to whether the trim tabs operate as servo or anti-servo type should be a matter of seconds for a qualified Moo flyer. More importantly if there is an issue, perhaps they might down tools temporarily to support the customers who have highlighted an error of the product already bought, and commit to fixing it.

 

And you could think a bit before posting like this in another developers forum

http://www.avsim.com/topic/473321-phenom-300-releasedfirst-impressions/page-4#entry3284820

 

Beginning to look like Flysimware are repeating the Chilean damn-the-customer-and-get-the-next-one-out-the-door mentality. This `small team` excuse is getting old. I said back in June what would happen if customer-supporting-customer suffered in this forum. We really need Flysimware to step up to the plate and be accountable here. 

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Louisdecoolste, this thread that brought up this issue is only 2 days old. We have released numerous fixes to the MU-2 in the time it has been out. 7 of them if I recall correctly. Personally speaking, as a customer, I have received more support, and responses from the developer at Flysimware than I believe anyone has from Carenado. And frankly I find your comparison of the two to be rather unfair. Show me the forum where Carenado interacts with their customers, takes their feedback, and fixes the issues.

 

To reply to the Trim Tab issue, Mark is now aware of this thread and we will see what can be done to rectify the issue. Give us a little time to fix things before jumping to conclusions and making silly comparisons.

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There are 4 major types of trim tabs.

 

1) TRIM TABS: 

Roll the wheel in the nose up position, and the tab moves down. Roll the wheel in the nose down direction, and the tab moves up. 

 

2) Balance Tabs: 

Some aircraft have very heavy control loads, especially at high speeds. That's where balance tabs come in handy. Balance tabs look like trim tabs, but they have one major difference: balance tabs are attached to the control surface linkage, so when the control surface is moved in one direction, the balance tab moves in the opposite direction.

 

3) Antiservo Tabs: 

Antiservo tabs are similar to balance tabs, but they move in the opposite direction. For example, when your elevator or stabilator moves up, the antiservo tab moves in the same direction.

 

4) Ground Adjustable Tabs:

The fourth and final tab is the ground adjustable tab. If you've flown a training airplane, there's a good chance it had one of these on the rudder. Ground adjustable tabs are just that: only adjustable on the ground. So how do you adjust it? By bending it left or right, preferably between two solid surfaces, like blocks of wood. But before you run out and start adjusting the tab yourself, it's a good idea to see what your POH or mechanic recommends first.

 

 

Operation for the MU-2B: Just has trim tabs!

The elevator trim tabs are cable operated from the elevator trim wheel on the left side of the power quadrant. Rotation of the trim wheel to NOSE to NOSE down mechanically position the elevator trim tabs, as shown on the mechanical inidcator adjacent to control wheel. The aircraft is equipped with electric elevator trim.

 

I sent a message to Joe our tech guy just to make sure as i could be wrong but these tabs are way too small to be any other type!

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Louisdecoolste, this thread that brought up this issue is only 2 days old. We have released numerous fixes to the MU-2 in the time it has been out. 7 of them if I recall correctly. Personally speaking, as a customer, I have received more support, and responses from the developer at Flysimware than I believe anyone has from Carenado. And frankly I find your comparison of the two to be rather unfair. Show me the forum where Carenado interacts with their customers, takes their feedback, and fixes the issues.

 

To reply to the Trim Tab issue, Mark is now aware of this thread and we will see what can be done to rectify the issue. Give us a little time to fix things before jumping to conclusions and making silly comparisons.

 

You say `seven fixes` as if it were a good thing ! 

As a`beta` tester I certainly wouldn't be referencing the number of fixes that have been necessary, it might reflect on the quality and quantity of my testing that went into the product. Just like Carenado, treating the customer like a paying beta tester. Whichi if the seven came at your instigation or those of your fellow testers ? So, hardly`silly comparison` - as well as yet further insult to the customer.

 

Back to facts: It's good to see the attendance of a real representative. Can we take it that this issue will be confirmed, dealt with and a further fix released if necessary before we see any further attention paid to the next monied product ? That would be excellent reassurance for the paid customer base. And un-Carenado like.

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You say `seven fixes` as if it were a good thing ! 

As a`beta` tester I certainly wouldn't be referencing the number of fixes that have been necessary, it might reflect on the quality and quantity of my testing that went into the product. Just like Carenado, treating the customer like a paying beta tester. Whichi if the seven came at your instigation or those of your fellow testers ? So, hardly`silly comparison` - as well as yet further insult to the customer.

 

Back to facts: It's good to see the attendance of a real representative. Can we take it that this issue will be confirmed, dealt with and a further fix released if necessary before we see any further attention paid to the next monied product ? That would be excellent reassurance for the paid customer base. And un-Carenado like.

Seems to me that the patches issued bye Flysimware have been small in size and directly addressing issues reported on these forums,no waiting for months to get things fixed like other developers. On the subject of fixes can you point me to an aircraft add-on that didn't need patching ? been doing this for many years and have never seen one. I have never beta tested for a flight sim add-on but have for several other program types and issues get through despite the very best of intentions.They always have and I have little doubt that they always will.

 

As for the elevator trim tab issue....For some reason the trim tabs on mine have the correct animations as per the examples noted above. I have no clue as to why that is and how it can differ from the complaints above. 

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Louis i am surprised your are complaining about updates. This is normal for any complex software. I always make sure our bugs are fixed within the first 6 weeks. And i only had this product for sale at my store for rev 1.0 to rev 1.3 before it hits the major outlets. The only reason we had to do more updates on this project was because my tech guy had a job change and could not be around. So i had to do his work and mine while trying to fix any bugs. One of the autopilot modes had a bug that was hard to fix as i found out it was not our coding it was how the animation was setup. So this threw me off for a while and it took a few updates to actually fix it. After all bugs were fixed i got back to working on my new project. Anyways why mention other projects since other company's usually have 3 or 4 projects going at once. I stick to one at a time minus updates. The trim tabs are fine and this entire topic is pointless to me unless there is in fact an issue. So let's get to the truth of it and we can fix it. As of right now and the last 4 months there has been nothing to fix. Also keep in mind i am 1 developer who owns and runs this business and the other team members are not full time. They have smaller specific tasks they do so i think i have done a excellent job for such a small Company. 

 

Not trying to make excuses but just trying to give you facts since i am shocked that you would post negative posts about how i do my business. I always say if you can do what i do all by yourself then see if you can do it better. As a paying customers i do agree you should report issues and we will fix them. Use our message center at our website. The forums is mostly to help customers on how to use our product and keep customers updated with news. Not for publicly trying to make Flysimware look bad!

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Then perhaps you should ask the Avsim people to rename the forum. the Flysimware Official Support Forum is unambiguous. It's the Support Forum. For Flysimware. Only now are we finding out it isn't. I'm sure Avsim will be as surprised as we !

 

As for looking bad, never been my intent. I simply reflect the level of support as I see it. which has gone from exemplary to crap, never mind excuses.

 

As for the trim tabs. Look again.

N130MS : Nose down trim (i.e. to trim the force out of a nose down application of elevator by application of nose down trim as seen on the forward movement on the gauge in the cockpit) shows the elevator trim tab rotating down, not up. If these are standard servo tabs they MUST operate in the opposite direction to the force being applied.

 

Your model does not do this, the tabs move in the same direction as the trim indicator - down for down, up for up. Or to put it another way, in the same plane as the control surface - forward yoke = down elevator, back yoke = up elevator. This is just wrong unless they act as anti-servos. And we are still waiting for confirmation on this point from you, the developer. Surely this was part of your basic research before selling the model to us public?

 

Please do so with all due alacrity. I really don't want to hear another word about the Lear until this bogus application is corrected OR we have physical confirmation that the system used in the Moo is of the anti-servo type, in which case movement in the same direction as the control surface IS correct. DA got it right with the Katana X (anti-servo). A2a get it right with all their GA birds.

 

Why is this so difficult. It's a basic requirement for correct simulation. The technical data will already be in your research pile and should be a matter of moments to find and publish for those of us who are now extremely confused.

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Never noticed but than I dont count rivets either. I guess some people have too much time on their hands. Im here to enjoy flying what is a lovey plane to fly. Not 100% accrate but than i havnt found one that is yet. After all it is a sim.

 

But thank you for doing to lovely planes, we are not allso picky.

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Louis i first posted how the elevator trim tab works as i thought that was what the post was about. Now i just checked the model you asked me to check and when i move the wheel up the tabs goes down and when i move the wheel down the tab goes up just like all of my other aircraft. So it is confirmed there is nothing wrong with this product. Think of it as there was a cover covering most of the wheel with the front of the wheel exposed. Then you will see the direction the wheel is moving. This may help since the entire wheel is exposed.

 

Our support for bugs is located on our help page at our website. Joe who is our beta captain is who runs this forum and has nothing to do with me since this support is to help customers and give them news. But you can start at topic on a major issue but unless we see the post we can't help you so please report at our website as well.

 

No reason for negative posting. And there is some positive posts as well, thanks for that as there is no reason to complain. The forums is not for publicly talking about how a Company runs their business or any other Company. Any further complaints on how we run our business may get reported to Avsim. Please keep your posts about the topic!

 

Also there is no reason to compare a 1 man developer to a Company that has more than 5 developers. If we had 5 developers it would take 2 months to make a perfect aircraft. I think i do pretty good for 1 guy with tech help from our other members. It takes me about 4 to 6 months to create 1 product. And i have not posted any news on the Lear here at Avsim at all. So why do you keep telling me you don't want to hear about this product until i finish the MU. The MU was finished 5 month ago. You need to check your Calender as your time is a bit off. But i want to say i respect all customers and i will research and fix any major issue that you find as long as they are major issues. So please keep your posts to the topic!

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Louis i first posted how the elevator trim tab works as i thought that was what the post was about. Now i just checked the model you asked me to check and when i move the wheel up the tabs goes down and when i move the wheel down the tab goes up just like all of my other aircraft. So it is confirmed there is nothing wrong with this product.

 

Sorry....I suggest you do a better research about this matter.

Efectively, when you move the wheel down the tab goes up...this is WRONG...
You move the wheel down for trimming nose-up and it's correctly confirmed by the Elev Trim Indicator reference line displacing down to the nose-up range... BUT the Trim Tabs raising in relation to the elevator is WRONG...  To release backward pressure on the yoke (elevator UP) the Trim tab must move DOWN (opposite) to keep the elevator UP.

Just to conclude:

Elevator and Rudder Trimming animations are wrong - to be fixed.
Lateral (Roll) trimming is correct.
Cockpit Trim wheels movement and corresponding Indicators are correct.

Cheers

 

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While your at it  how about Fixing the Autopilot so when yo reach the Desired altitude the  ALT Cap  light goes off and the ALT hold comes on like

it's Supposed to.

 

I hope you understand some of the  Frustration, we all realise that people have a life, I do as well and believe me you don't want to walk in my shoes

right now. I myself couldn't wait for a MU-2 and so I took the chance hoping that I would have a project that would continue to be updated and fine tuned

but you ran off to do the Lear. Not sure if that's your Bad or my Bad  but I'm  guessing that the MU was and will be your best seller.

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Well we've had more news on the Lear, nothing at all on the remediation of this issue for existing customers. So I'm guessing that's that.

Marty, it's not You Bad. 

 

Sadly I think it's time to move on. Support response times have become intermittent and sparse while the developers get on with their excuses/lives. Disinterest at both ends means it's probably time we do likewise. 

 

Such a shame as good developers are hard to find.

 

Wonder if the trim tabs on the Lear will work correctly? 

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Would never of noticed if it hadnt being mentioned, still cant see tha tfrom teh cockpit and would need to zoom right in so isnt a bother for most.

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Same here. it wasn't mentioned in earlier complex discussions that led to fixes, but now that it's highlighted it's pretty fundamental to the perceptions of some customers apparently, so needs fixing.

Unless they don't care about current customers in the focus on finding new ones with the next release. Which would be a mistake.

 

As well as `lesson learning`  - I guess all their releases need reviewing in the same light as it throws doubt on the technical competence of the developer. This will be my only Flysimware product so can't check the rest. I can't risk the Lear not being good enough. It's my money and I like to spend it wisely.

 

Shame really, as I thought the ongoing commitment to improving the product would lead to a Real Air or A2A- style customer care approach by the vendor. But they've demonstrated a short attention span like so many others. 

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From what I see the ylearn from each new model, than hopefully will go back and use those new thinhgs on teh older models. Get more business that way. Unlike some others

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From what I see the ylearn from each new model, than hopefully will go back and use those new thinhgs on teh older models. Get more business that way. Unlike some others

 

Could be a lot of trim tab fixing coming, then. Personally, I'd prefer them fix things before they move on. After all, they've taken the money.

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So you guys are saying you want the elevator trim tab to point down to fly up?

 

This aircraft uses trim tabs not balance tabs nor antiservo tabs!!!!!!

 

Trim tabs do not move the control surface linkage. They are on their own linkage and act like the main control surface. 

 

1) TRIM TABS: 
Roll the wheel in the nose up position, and the tab moves down. Roll the wheel in the nose down direction, and the tab moves up. 
2) Balance Tabs: 
Some aircraft have very heavy control loads, especially at high speeds. That's where balance tabs come in handy. Balance tabs look like trim tabs, but they have one major difference: balance tabs are attached to the control surface linkage, so when the control surface is moved in one direction, the balance tab moves in the opposite direction.
3) Antiservo Tabs: 
Antiservo tabs are similar to balance tabs, but they move in the opposite direction. For example, when your elevator or stabilator moves up, the antiservo tab moves in the same direction.
4) Ground Adjustable Tabs:
The fourth and final tab is the ground adjustable tab. If you've flown a training airplane, there's a good chance it had one of these on the rudder. Ground adjustable tabs are just that: only adjustable on the ground. So how do you adjust it? By bending it left or right, preferably between two solid surfaces, like blocks of wood. But before you run out and start adjusting the tab yourself, it's a good idea to see what your POH or mechanic recommends first.

 

And you guys keep getting on my case that i am ignoring this fix when i have nothing to fix. My beta testers passed the model as correct and i passed the trim tab as i made the product but 2 people say it's wrong and 99% of other customers never mentioned this issue. Like i said i would fix it if it was wrong but according to everyone it's correct. Now you post that my sells will go down hill because i don't want to fix something that is not broken or waiting for more evidence on this topic.

 

Here is a list of updates for the MU coming this Fall: (It's better to do all updates at the same time since there is a lot of stores to update. I have been collecting feedback for 4 months and will do this after the release of the Lear. I do this for all projects. And as the Lear bugs are being reported i will be working on the MU and updating the Lear for the first 4 weeks until all major bugs are fixed just like i did on the MU. When the MU got released i updated the Cessna 441 with all updated collected over 4 months. So this pattern seems to work as the 4 or 5 months gives a good amount of time to collect small minor updates and new features. If i update our partners stores every time we find 1 bug they will no longer want my products on their site. So i hope this information gives you an idea on what it takes to be a good developer. And according to my emails i have the best customer service in the industry. We email back within 24 hours 7 days a week 365 days a year. But unless you use our email ticket system forums are not my job as Joe takes care of Avsim. He has been working 2 jobs and so i am here to post for him.

 

Props getting more blur effects
Adding GPU unit.
Dimmer lights
Updating manual to show avionic switch location.
Fuel transfer ability using Doug's fuel dump gauge (Paying for commercial use)

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