Elevator Trim

stevve2023

New member
New user of RealFlight and forum. My system: Realflight 9.5, InterLinkDX, HABU STS 70 mm 4S. Does this: "Elevator Trim is entirely a function of airspeed and engine RPM." mean that RealFlight sets the elevator trim to keep the model level and the users does not need to trim the Habu elevator for landing? Are there any other settings that need to be set other than "Habu STS 70 mm 4S"? I'm not using the LAS module.
 
Where are you seeing that statement at? I'm curious about what context that's in.

When you select the Habu STS 4S, this is the description that's provided.
This is a 4S battery powered variant of the Habu STS 70mm EDF.

Engineered for improved low speed handling and performance to make flying and landings easier, the E-flite Habu STS (Smart Trainer with SAFE) 70mm EDF makes it possible to succeed in learning to fly with a jet as your first radio controlled (RC) airplane! Based on one of the best Electric Ducted Fan (EDF) sport jets ever designed, it’s been optimized with the addition of SAFE (Sensor Assisted Flight Envelope) technology featuring Beginner, Intermediate and Experienced flight modes to make it easy to fly successfully. This makes the Habu STS 70mm EDF the easiest to fly RC jet EVER, and the perfect choice to satisfy any RC pilot’s desire to fly a jet!

Use the three-position mode switch (B on the Spektrum InterLink DX controller) to select between:

-Beginner Mode
In this flight mode, the airplane has pitch and bank angle limits to prevent over-control that can result in a loss of orientation and crashes. When the control sticks are released, the airplane automatically returns to level flight on its own, allowing you to relax and enjoy just "steering" the airplane through the sky. This flight mode also makes it easier to take off and land.

-Intermediate Mode
This flight mode allows more freedom in pitch and bank, but still prevents significant over-control and the airplane does not return to level flight on its own. This allows you to make tighter turns and to climb and descend faster as your skills advance.

-Experienced Mode
In Experienced Mode there are no pitch or bank angle limits so you have complete control! You can even fly inverted (upside down) and perform aerobatic maneuvers including loops, rolls and more.

-Panic Recovery
If you lose control of the airplane in the Intermediate or Experienced flight modes, simply press the Panic Recovery button or switch to Beginner Mode and release the control sticks. SAFE technology will automatically return the airplane to level flight.

SAFE is controlled by Switch B (Channel 8).

When in the Beginner Mode, the SAFE self-level feature is active as described above. There's another feature of SAFE with a throttle-to-pitch mix, and that's usually configured to add some elevator input (I wouldn't call it "trim") when the throttle is raised beyond a certain point (usually 75%). That's how the throttle can affect the elevator, but it should only happen in Beginner Mode.
 
Search for "Trim increment" in RealFlight 9 to find the quoted line in my post.

I'm using "AS3X: Experienced" as shown on the Flite Modes Gadget. I'm not having trouble flying in RealFlight, except I'm doing something wrong because the Habu tends to bounce badly on some landings. Sometimes landings are perfect and I'm not sure what I'm doing correctly at those times.

I have set up my DX9 per the Habu manual. Low rates actually increase control rate at neutral stick position and reduce total travel. I was assuming that rates only change in Experienced flight mode and not in the Safe modes, but that seems to be incorrect.

So, when landing is it recommended to just use the throttle stick to change descent rate? On other planes, using the throttle stick seems to be more precise than using the elevator to increase or decrease descent. Is the elevator used to flare? If this is the case, I will continue practicing with RealFlight so I'm practicing the right way.

50 landings later. . . Quote from Intermediate Mode above: "This allows you to make tighter turns and to climb and descend faster as your skills advance." The problem is that "skills" are not defined in terms of controller setup and control methods used to land. This forum is not providing procedures to get optimum performance of RealFlight. There should be a section in the forum that provides skills information or a link to an appropriate Internet location. I'll spend some time searching the forum to see if the information gap is filled in this forum. It's interesting that the second video that shows up on a Google search for Habu STS videos, shows that the pilot has a need for this information to improve his landing performance.
 
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RealFlight does not make any adjustments to radio trim settings. Those are entirely controlled by the user. I think what that user was pointing out with the line you quoted is that elevator can only be trimmed for a given airspeed. If you trim a plane for level flight at 50 MPH, you are likely to find that it does not stay level at 100 MPH, and vice versa. (All kinds of factors such as the plane design will affect how much it actually varies.)

One of the things SAFE does is add actual elevator input just as if you had done it yourself, based on what its sensors tell it is happening with the aircraft and sometimes based on things like throttle position (in Beginner mode). The LAS variant of the Habu is a special case that provides additional control intervention to assist with smoother landings when it detects that it is approaching the ground. You might find that using it for a little while and watching how it behaves helps you see what you should do, which you could then go back to a non-LAS variant to practice for yourself.

Landing takes practice! Getting good and smooth with it takes even more practice. The fact that you're paying attention to all of these things is a good start. I suggest searching other more general RC forums for real-world advice on good landing technique and practice methods, which you can apply to your time training in RealFlight. The best approach can vary from model to model and airplane type to airplane type. In general, you would typically slow on approach and keep the nose up a bit, using throttle to control the actual descent rate. With practice you'll get better at finding the balance point. Flare with elevator at the end. If you're bouncing a lot, it might be that you're coming down too hard. It is also quite likely you're carrying too much airspeed.

Actually, I can't believe I didn't lead with this: RealFlight has a built-in Flight Training instructional feature, and one whole set of lessons is performed using the Habu! I strongly recommend you check those out.
  1. From the main menu select Training -> Flight Training...
  2. Select the "Habu STS" tab.
  3. You will see 4 different classes. Each one contains a handful of lessons. Click on one of them to view its lessons.
  4. Select a lesson and click Begin to get started.
As a beginner, I recommend you view them all in order starting from the beginning. "Habu Beginner Mode III" covers landing specifically.
 
Re: rates and expo, they are always active in RealFlight, regardless of flight modes.

You can either choose to control them on your TX, which proportionally limits the output values sent to the sim, or dedicate a channel to controlling them in the sim, which means assigning them to a switch on your radio that tells RealFlight which rates to select using the values it has configured for each model.

What you need to avoid is doubling up, meaning a situation where you select low rates on your TX and then RealFlight applies its own low rates to the already scaled values your TX sent. Same thing with expo, which can end up multiplying the same way. There is a checkbox within the controller profile setup screen called "Enable Software Radio Dual Rates and Expo". Ensure that is unchecked if you want to control rates and expo on your radio. This will cause RealFlight to never apply its own settings on top of yours.
 
Very helpful information that even answers unasked questions. After watching videos and changing some settings, landing is much easier in all 3 modes. Verification of landing process methods makes training easier. Training >Flight Training, "New" tab appears to be an update of the "Habu STS" tab and adds more videos. Real Flight Training is the best training process I've ever seen on the Internet or at our flying field! Nothing compares to Real Flight and I don't know of anyone in our club that could not learn to fly the Habu STS 70mm 3S or 4S. The only basic skill to learn first would be turning left and right with the plane coming towards and going away from the Pilot. I agree with Real Flight that if someone flies RC, they can learn to fly the Habu Jet on Real Flight and flying the real model at the field would be very easy. A number of flights on RealFlight will make a non-flyer able to fly in Beginner Mode easily. I used to hate "Safe", but Safe in Beginner and Intermediate Mode is made easy and showing both how to do perfect and bad landings explains how to do landings successfully. Flying in Experienced Mode with AS3X leaves no doubt in my mind that Real Flight Training will sell many models and looking in RealFlight 9.5 will be the first place I'll look before buying another model.
 
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I'm very glad you're finding RealFlight so helpful as you learn to fly! Thanks for reporting back.

At some point we reorganized the Flight Training videos so that they are grouped by the vehicle used in the lesson. That probably occurred for 9.5S. If you saw "New" and "Classic" instead it's because you have an older version of the software.

If you'd like you can exchange your RealFlight 9.5 serial number for a 9.5S Steam key and upgrade for free. See this site for details: https://keyexchange.realflight.com/

Best of luck!
 
I see New and Classic when I click on Training. There is no information about how and why Steam is involved with RealFlight. The disc case only says RC Flight Simulator on the cover and contains DISC 1 and Disc 2. Are you sayaing that dealing with Stream is the only way to update RealFlight? I've had nothing but trouble dealing with apps that are sold digitally and I've heard bad things about Stream.

I'd also like to know which way is better to use expo. On the InterLink DX controller or in RealFlight? Are there any performance improvements in 9.5S or is it just more models and other fixes?

RealFlight.com has RealFlight Simulator Evolution and RealFlight Trainer Edition. Is there a significant difference between these and how do they differ from 9.5S? Sorry for all the late quesitons, but RealFlight has been sitting on my shelf for about 2 years and it looks like a lot has changed with RealFlight.

Beginner and Intermediate mode are working well for me. What I need to know is if Experienced mode needs to have the elevator trimmed at 1/2 throttle for level flight (using the InterLink DX with expo settings now; I am a mode 1 flyer). Elevator trim does not seem to have any effect in Experienced Mode on the InterLink DX. I understand this is done automatically by RealFlight in Beginner and Intermediate

If I put my experience on the club website, I suspect I will get a lot of questions from club members. I appreciate what you have provided so far that has been a huge help! A number of members have older versions of RealFlight, so it would help to know if the Training videos are only available on 9.5 and higher and how the other two versions of RealFlight may impact a purchase decision.
 
Steam is how we deliver the software now. RealFlight can of course be purchased directly from Steam online. It can also still be purchased from other places, such as in RealFlight boxes in hobby shops. It's just that inside that box, instead of DVDs like you got, there is an alphanumeric code for redemption on Steam in order to actually obtain the software.

I suggest viewing this post and this post of mine for more information on these topics. (I suggest saving time and not reading the entire thread. There was a lot of initial trepidation about Steam which has largely been resolved since then.)

RF8 was the first version of RealFlight to be available on Steam, added several months after its initial release.

RF9 was released simultaneously on DVD, as a digital download through Tower, and Steam.

9.5 was a free update for all editions.

9.5S was the first version to be available exclusively through Steam. It is still a free update for all RF9 users. Steam edition users received it automatically, as with all updates through Steam. DVD and Tower Digital Download edition users must first exchange their edition for the Steam version. This exchange is free and is accomplished through the following site: https://keyexchange.realflight.com/

9.50.038 is the last update released for RF9 prior to 9.5S. Hopefully you are already running that version. It is available to you via the RealFlight Launcher. Subsequent updates were available only to Steam users (which includes everyone who has performed the above exchange).

I'm not sure specifically what bad things you heard about Steam, so I can't really speak to that. FWIW it has a very large userbase and by the end of this year will have been around for two decades. I use it personally and am pleased with it. It offers a number of advantages both for us as software developers/publishers and for our users. A few you may care about:
  • You don't need a DVD drive (for years now most computers have not included one).
  • You don't need to worry about losing or breaking your DVDs.
  • You don't need to enter a serial number or worry about losing it.
  • Software updates are provided automatically.
  • You don't need to register online to receive software updates.
  • Installation on other PCs is super easy. All you need is your Steam login info.
RealFlight Trainer Edition is a lower-price version of RealFlight with a limited feature set. It offers the basics and is a good way to try out RealFlight and the hobby with a smaller initial investment. It can be upgraded to RealFlight Evolution at a reduced price as well, meaning you can take that smaller step first then upgrade to the full version later if you choose and only end up paying an extra $10 out of pocket compared to buying Evolution in the first place at its regular price.

There is a substantial difference between Trainer Edition and the full versions of the sim. Many features and much content was trimmed out of it. But for someone seeking just the basics on a budget, it's still a great option for learning to fly.

This announcement is a good place to start learning more about RealFlight Evolution.

If you're using the InterLink DX, just select the "InterLink DX (Mode 1)" radio profile in the Select Controller dialog and call it good. One of the great things about using the InterLink is that everything just works without additional setup.

The InterLink DX does not have any settings of its own. It cannot apply different rates or expo to your outputs. Each model in RealFlight has what we call a "software radio" which is set up with selected values for those things. For example, one model might have 70% elevator on low rates while a different model might have only 50%. Similarly, different models can have different amounts of expo set up on their different channels. When you flip the rates switch on your InterLink, that just sends a different signal on that channel which RealFlight's software radio is watching for that tells it whether to use the low or the high rates that are already programmed into it. Whatever expo settings exist in the software radio are applied to your inputs once they reach RealFlight, but nothing ever changes on the InterLink itself as far as the output values it sends.

If you're interested in more of the nitty gritty of setting up your own radio for use in RealFlight, I suggest reading the Radio Interface Help document available from RealFlight's Help menu. It can get a bit esoteric. As long as you're using the InterLink (which provides the best experience), you don't need to worry about any of that.

To reiterate what I said in an earlier post, RealFlight is never modifying the actual controller trim for you. But that might not actually be what you meant. SAFE modes do use gyros to help stabilize flight, which is a bit different. It's acting on your behalf as if you yourself had moved the sticks.

You should absolutely see results from modifying trim values in AS3X mode. You should hear a beeping sound when you increment or decrement any of the trims. You can also turn on the Radio gadget and confirm that RealFlight is seeing those inputs, since the tabs will move visually, and will be colored red except for when centered.

However, maybe what you're encountering is that even when adjusting the trim to max it's not enough to keep your plane level at half throttle. That would be a different matter. Half throttle is not a lot of power for many models, and the impact of trim settings is limited. Even full trim is not the same as full stick input. At half throttle I expect to hold a certain amount of up elevator myself just to keep the plane in the air and level (at least for most), and for some models the amount will be more than what trim alone can manage.

Re: Training videos in different versions: 9.5S adds a similar set of lessons using the AeroScout for people who are starting out with that particular model. They are essentially the same as the ones you have experienced with the Habu. Evolution has the same lessons as 9.5S. Trainer Edition has the same New lessons as 9.5S and Evolution but none of the Classic lessons.

Phew! That was a lot. I hope it helps!
 
Yes, that was a lot! And very much appreciated. I think you got me updated on what's happened in the last 2 years. From what you're saying above, I think the best results will occur if I reset RealFlight to factory defaults for using the InterLink DX. What I am experiencing in AS3X mode is also having to hold in a fair amount of up elevator, same as described above, but in AS3X the controls are far more sensitive and require miniscule stick movements. I assume that the real model will be the same when flying at the field with my DX9 or NX10.

I am not hearing a beeping sound when I increment or decrement elevator trim on the InterLink DX. Nothing lights up or moves on the gadget InterLink DX on the monitor. So, I tried all the trims in AS3X mode and nothing beeps or moves, but when I move the sticks the control surfaces and sticks move. Do I need to Restore Defaults or Reinstall the 9.5 Real Flight software and update again to the latest version?

If I upgrade to 9.5S, do I have to be on the Internet to Install the software?

Is the 9.5S installation a download file that I can save on DVD?

If I reinstall 9.5S or above, does the software have to be activated online at Steam just once?

Do I need to uninstall RealFlight before reinstalling?

If I take my computer to a club meeting to demonstrate RealFlight, do I need an Internet connection to run RealFlight?

Seems to work with the ethernet cable unplugged. I already found out that Training requires an Internet connection to run.

Thanks again for such an outstanding response to my questions.
 
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What I am experiencing in AS3X mode is also having to hold in a fair amount of up elevator, same as described above, but in AS3X the controls are far more sensitive and require miniscule stick movements. I assume that the real model will be the same when flying at the field with my DX9 or NX10.
It's hard to know for sure without observing or experiencing it firsthand. Some of that sounds right. You will definitely need to be the most judicious with your inputs in AS3X: Experienced mode compared to Beginner and Intermediate SAFE modes, but the plane shouldn't actually be any more responsive in Experienced vs. Intermediate mode--it's just that the latter imposes limits on how far you can roll, for example, whereas Experienced mode does not. The roll, pitch, and yaw rates should be the same between them up until you hit those limits.

Does the radio gadget accurately depict the actual positions of the sticks when you move them? If you're finding that tiny movements cause the stick to jump from the center all the way to the maximum or minimum possible position, or anything like that, then something is wrong. The first thing I would try is recalibrating your controller in RealFlight in that situation. If that didn't help, I would start to suspect the device was actually defective. If the movements in the gadget look about right, though, then you should be good.

(Side note: Have you set the radio gadget display mode to Mode 1 to match your controller configuration?)

I am not hearing a beeping sound when I increment or decrement elevator trim on the InterLink DX. Nothing lights up or moves on the gadget InterLink DX on the monitor. So, I tried all the trims in AS3X mode and nothing beeps or moves, but when I move the sticks the control surfaces and sticks move. Do I need to Restore Defaults or Reinstall the 9.5 Real Flight software and update again to the latest version?
I'm starting to wonder if there is an issue with your controller. To be clear, the beeps will come from the RealFlight software, not the InterLink itself. So if you have the sound muted in software, or the volume turned down low, you might not hear them even if they are playing.

I've attached a video showing the expected behavior. You'll have to extract it from the .zip containing it.

At this point I think restoring defaults would be a good step just to start fresh. I don't think reinstalling is required.

If I upgrade to 9.5S, do I have to be on the Internet to Install the software?
Yes.

Is the 9.5S installation a download file that I can save on DVD?
No. If it helps, you can think of Steam as much like the app store for a smart phone. When you install an application, it downloads straight from Steam.

Now, it can be a bit of an adjustment going from DVD, where you feel some sense of physical ownership, to a digital-only purchase where in theory it could be taken away from you. I get that completely. Steam has been around since 2003, though, and is very successful. I personally own a lot of software through them. I think the risk of them vanishing overnight is almost zero. But, it is a decision everyone has to/gets to make for themselves (as it should be).

If I reinstall 9.5S or above, does the software have to be activated online at Steam just once?
The act of uninstalling would deactivate it, so it would need to reactivate the next time you run after reinstalling. But reinstalling also requires being online, so it shouldn't impose any extra burden.

Do I need to uninstall RealFlight before reinstalling?
I'm not sure if you're asking about your 9.5 installation or the way 9.5S behaves, but in both cases the answer is yes.

Steam has a "Verify integrity of game files" option that will scan your installation and look for any stock files that aren't right and correct the issue without having to completely uninstall and reinstall. (Of course it has to be online to do that.) It's a pretty slick feature.

If I take my computer to a club meeting to demonstrate RealFlight, do I need an Internet connection to run RealFlight?
Seems to work with the ethernet cable unplugged. I already found out that Training requires an Internet connection to run.
No. Once activated, and assuming you've updated to the latest available version via the Launcher, your 9.5 installation should never require the Internet for anything else unless you want to use the Multiplayer feature. I'm not sure what made you think the Training feature does, but it will also work just fine without being online.

For Steam versions, you can put Steam into offline mode and use it for long periods without an Internet connection if you need to. The Steam client would still need to run (it essentially replaces the RealFlight Launcher), but it would not need to be online. It will eventually require you to connect and sync up, but after that you can put it into offline mode again if you choose. It's best if you can leave it connected, though, in order to automatically get updates when they become available.

Thanks again for such an outstanding response to my questions.
You're welcome!
 

Attachments

  • Radio Gadget Trim Behavior.zip
    2.5 MB · Views: 5
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I went thru your list of things to check and didn't find anything wrong, so I Restored Defaults, selected InterLink DX (Mode 1) controller, checked channel 2 and 3 to see that elevator and throttle were on correct sticks, and selected the radio Gadget and Mode 1. I then found that the trim red light came on and there were lots of beeps and movement of the trim position on the Gadget Radio display. Problem solved!

Before the Restore Defaults, I had installed a preview cumulative update for Windows 11 and a preview update for .Net Framework 3.5 and 4.8.1. This seems to have made some changes to the Windows 11 task bar display and I can now move the RealFlight window to the taskbar. I don't know if the Windows updates made any changes to help fix the Gadget Radio Trim problem.

Thanks again for all the help to solve this problem!
 
For some reason I can't respond to this forum: https://forums.realflight.com/index.php?threads/announcing-realflight-evolution.56982/

I'm looking for a list of all models in RealFlight Evolution if I update from 9.5 to Evolution on the Steam website for the discounted price. Also, are expansion packs available at additional cost? Is a price list available?

I am using InterLink DX Simulator Controller changed to mode 1. Besides the switch on the back of the controller, is there another change required other than the "Edit Profile: InterLink DX" page? Sometimes when I start up RealFlight, I get a message to calibrate the controller and when I edit the profile, it is not in Mode 1.
 
For some reason I can't respond to this forum: https://forums.realflight.com/index.php?threads/announcing-realflight-evolution.56982/

I'm looking for a list of all models in RealFlight Evolution if I update from 9.5 to Evolution on the Steam website for the discounted price. Also, are expansion packs available at additional cost? Is a price list available?

I am using InterLink DX Simulator Controller changed to mode 1. Besides the switch on the back of the controller, is there another change required other than the "Edit Profile: InterLink DX" page? Sometimes when I start up RealFlight, I get a message to calibrate the controller and when I edit the profile, it is not in Mode 1.
You can see all the aircraft and flying sites here.

https://www.realflight.com/product/...tor-with-interlink-dx-controller/RFL2000.html
 
All things RealFlight are working well. To sharpen my throttle skills, I've been doing RealFlights with using only the throttle and ailerons to fly around the field. I can now fly Beginner very well, Intermediate is a bit tricky, but different techniques make it easier. Experienced Is fun and not quite as easy to land, but I'm far more capable now. I did a short video (https://www.lakesawyerhawks.org/video/realflight_habu_sts_1.mp4).

I'm ready go to the field with the real Habu, but weather has been a bit rough for flying. In the meantime can anyone say just how well RealFlight simulation is to the real model?
 
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