I’ve recently revived the PR Fredrik Hedberg did a long time ago for dual helicopter support in ArduPilot to get it ready for merging into master. Recent changes in the structure of ArduPilot makes supporting these vehicle types much easier.
Here is a video of flying the Chinook model in RealFlight using ArduPilot SITL
The PR for dual heli support is here:
I look forward to some people trying this on a real Chinook style heli!
really cool! The Singapore team will love this!
THANK YOU Tridge for making it !
Great work,cool.but we can not to reproduce
We do love it, thanks @tridge! It’s been working great in SITL.
oh? Did you try the built-in dual-heli sim? That should work.
It doesn’t have any nice graphics, so makes for a lousy video, and the aerodynamics modelling is very simple compared to RealFlight, but it does allow you to test the code.
today I have contact to James Lamorticelli,he reply that let us review and get back. 
The tandem heli PR has now been merged into master. Now we need some brave testers to fly it on real vehicles!
I am here a friend is stepping up the production of vertical dual-axis dual-wing structure of the RC aircraft, I will let him boldly try this “Chinook” firmware!
Thanks to the development team’s efforts!
What methods and steps can I use to match MissionPlanner with Realflight 7 to achieve simulated flight testing? I have been trying, but no way to start.
@zhangsir unfortunately the plugin that allows realflight to connect to ArduPilot is in closed beta. It is only available if KnifeEdge allows you to join the beta program. I hope it will be released for everyone sometime soon.
Oh! Understand, thank you for your answer.
Look forward to the future open it
This is my heli using mostly fhedberg’s code which is based on AC3.4.x.
But I’m not brave enough to try this on Master…
I’m about to test it.
Took me a while to find how to use this frame.
FRAME_CLASS must be set to 11 (it is not shown as a choice in Mission Planner)
good luck! make sure you get video
I must say that the code I use will be slightly modified.
You can see my code here:
Detailed build of the heli being tested:
However, I’m dealing with a problem at the moment.
For more detail please see:
Any help will be appreciated. 
Report: it’s unflyable.
Still have to check whether it is my modified code or not.
First, the servos became over-responsive. I need to lower CYC_MAX from 1800 to 500.
And when tilting the heli, servos will go to extreme very quickly with imported PIDs.
Hi @tridge,
I like what you have been doing integrating SITL with RealFlight. Here am running RF9, I was asking if the plugin is already available to use.
I am interested to have my hand on to it.
Thanks
yes, see docs here:
https://ardupilot.org/dev/docs/sitl-with-realflight.html