Comment: I enjoyed your web site, I am into twin rotor helis, I have just built a Twinn Rexx, which I purchased from Joe Orlando, I can understand and respect the level of work you have put into your project to get it flying, well done. I am not interested in so much of the scale aspects it's the mechanics of getting it to work and function correctly that does it for me, which I think I have now achieved. Regards, Mick

Mick: Many thanks for your comments on my rc Chinook project.   If you have any photos or details of your Twinn Rexx that you would like to share with other people please let me know and I will publish them.   Regards, Richard

Comment: Hi Richard Have looked through all the pictures on the web on your connstruction of the chinook. I am up to the challenge now myself to build one and the fuselage already gives a good starting point. Still some questions come to my head in regards to construction:As I will be maxed out after 500 chars I will need to post my questions in several sessions I guess. Here is no 1 What rotordiameter do you use and what is the average headspeed that you fly on your Chinook ? Regards Leon

Leon: It's good to see someone else talking up the challenge.  I'm using Vario 3 blade heads with 765mm long blades giving me a rotor diameter or 1680mm, the head speed is around 1300rpm.  I would like to reduce the head speed but it become very slow and unstable at lower speeds.  I've just upgraded the engine to a Zenoah G260rc from the original G230rc to give me a bit more torque now that the fuselage is on.  Regards, Richard 

Name: Leon Nollgen

Email: fatima-schoenmaker@hotmail.com

Comment: I see that you are using 10 mm shafts from engine to the mechanics. did you base this on calculations or was it just a choice of safety. My reduction from engine speed to main shaft speed is in the mechanics itself and I was considering to use a 6 mm shaft on the drive train. Would you think that is too weak ? Am I correct that the angles from the main shafts are 9 degrees for the front one and 4 degrees on the backside ?

Leon: Do not under estimate the torque required to turn 2 multi-blade heads, would you drive a single multi-blade head using just a 6mm shaft? When I designed the mechanics, from day one I decided not to compromise on the transmission, because the blades interlock if something in the drive breaks then the blades come out of sync and before you can do anything 6 very expensive baldes and 2 multi-blade heads are scrap!  My main center drive shaft is 12mm dia. and then reduces to 10mm either side to the 90 degree gear boxes.

You are correct with the front and rear angles, I angled the engine at 9 degrees to give a straight run to the front gearbox and then fitted a good quality universal coupling to take the shaft up to the rear gearbox.

Regards, Richard

Comment: Hi Richard I am coming to the final construction of my mechanics and before its maiden flight I wanted to ask you what DCP do you have in degrees between front and back whem you max nick function?

Comment: Im a CH-47 Crewchief and Mechanic and would like to say thanks for making a model that looks the most realistic. also having a fully articulated rotor head make any diffrence in flight or hinder stability.