Hangar 7 Rainbow Aviation MGM COMPRO REX 30

8-20-2017

Great news,

We finally settled on our next electric propulsion system. MGM Compro REX 30 is on order, and Martin Dvorsky, the owner of MGM Compro as promised to have a motor and controller for us to display at the upcoming 2017 AirVenture airshow in Oshkosh Wisconsin. We have been working on this project with Martin for quite some time now. We are trying to have a complete system supplied by MGM Compro that will be basically plug-and-play for EMG-6 customers. Everything from the batteries, battery management system, charging systems, instrumentation, motor, and ESC controller. We will be undergoing all of the flight testing before we have a recommended package for the EMG-6 customers. The whole goal of this is to have a perfectly matched, reliable, electric motor system that can be basically bolted in the aircraft with minimal knowledge about electric power plant systems. We will document the installation and testing of this powerplant system from day one you apprised of all of our difficulties as well as successes. These guys have been doing this for quite some time now and are starting to become 1 of the leaders in the industry. They have a whole series of successes on other aircraft and looking through the documentation for the motor, controller, BMS, etc. it’s obvious that they know what they’re doing. Although much of this information is proprietary we will try and share with you as much information as possible as we proceed through the testing and installation procedures. Obviously the timing is not great for having a flying electric airplane at the years airshow. But that being said, it’s so crazy at the air show anyway that it’s best to have a known quantity that has been very well tested before you put it into the arena of all the craziness of Oshkosh. I can make you this promise though, next year we will have a flying electric EMG-6 at the air show come hell or high water.

Visit The MGM Compro Web Site

MGM Compro Web Site “Click Here”

This was the design information that we provided to MGM Compro so they could match the windings of the motor specifically for our application.

Design speed for aircraft 60 MPH
Prop RPM (direct drive) Max 4200RPM
Max Torque ~ 50 ftlbs
Cruise rpm ~ 3000 RPM
Cruise Power Requirement ~12-16 KW
Recommended prop 3 blade 48-24
Aircraft gross wt 750Lbs

Picture Gallery for the REX 30 and the Controler

8-20-2017 Controller

We have some pictures of the controller for the Rex 30 motor.
Mounting screws

There are total of 4 screws on either side of the main housing that look fairly substantial that can be used for mounting the controller into the aircraft. We will be primarily responsible for the installation of the electrical system as supplied from MGM Compro. As a result the integration of how all of this stuff fits into the airframe becomes particularly of interest to us.
Power in

There are a redundant set of power leads coming into the controller. The 2 center leads are negative and the 2 outer leaves are the positive leads.
Power out

Coming out of the opposite side of the controller are 2 sets of three-phase power, once again, redundancy.
Top view

The top view of the controller with a smoked piece of Plexiglas as a cover. Each of the screws has torque stripe paint to prevent tampering with the controller. It's obvious that Martin doesn't want you to screw with his stuff.
Weight, 3.32 pounds

In this picture here we show the bottom of the controller with the 2 cooling fans. Once again the amazing weight of the entire controllers only 3.32 pounds. We will be looking to mount the controller in a position to maximize the amount of cooling provided to both the controller, batteries, and motor system. 1 of the design characteristics of the airplane has from the very beginning been to capture all of the air flowing around the pilot and coming into the cabin area and use that air that would normally be simply drag and convert it into cooling air.
Weighing in at only 12.38 pounds

It was good to finally get a weight on the Rex 30 motor itself. 12.38 pounds is pretty phenomenal when you consider the power output.
Hand wound

Even though the motor is hand wound and are basically being built one at a time by hand. The workmanship is outstanding.
Drive end view

The Rex 30 motor is an out runner. The magnets are attached to the outer ring which is connected to the center hub. This is the attachment for the propeller. The bolt pattern is a pattern that I am not familiar with however I am sure that there are several European propellers that match this hub pattern as well. If necessary we will make an adapter which will simply mate the hub to a propeller of our choice. We are still working out the exact propeller that we want to use on this particular motor.
Profile view

The side view of the motor shows its compact design.
Winding close-up

The close-up of the windings and a small circuit board. The small circuit board is obviously for some of the sensor pickup information. We still do not have any documentation on all of that. I'm sure that will be forthcoming relatively soon and we will then be able to give you a more in-depth explanation of each of the components.
Power leads

A look at the power leads and the supporting block coming out of the motor windings.
A close-up look at the power leads.