Hanagr 9 Twist 60 eConversion to eFlite Power 90 Brushless Motor

If you follow this blog you may have seen the pictures and videos of my Hangar 9 Twist 60 that I post occasionally. This post is about my conversion of the plane to a brushless motor setup as well as some statistics on the Power 90 brushless motor power system.

I had originally built the Twist with a Saito 1.15 four stroke nitro-methanol engine and it ran pretty good and I was happy with the performance and flying. When I got into the hobby as a teenager, and up till 3 or 4 years ago I had mostly nitro-methanol model airplanes and helicopters. These days most all of my stuff is electric. I like electric and it had become much more reasonable in regards to cost and available hardware. With electric it’s easy to just go out for a quick flight on the smaller stuff, but I’ve never done a mid-size electric plane so I was a bit apprehensive, mostly about the cost of the Lithium Polymer batteries required to power a larger motor and the larger and more expensive speed controllers that go along with it.  Considering the cost of a new Saito 1.15 at the time, I probably should have gone electric directly.

After dealing with the oil slop mess and tuning and having to carry a completely separate set of tools with me to the field when I take the nitro plane, I decided to spare myself a lot of trips between the truck and the house and truck and the field over time as well as having to remember Windex and paper towels, I decided to convert it over to a brushless electric.

Here are a couple of photos of the plane with the Saito 1.15 four-stroke engine.  It looks quite good!

Twist 60 wtih Saito 115 4-Stroke

Twist 60 wtih Saito 115 4-Stroke Closeup of Motor

REMOVED: Throttle Servo, Fuel Tank, Saito 1.15 4-stroke 16×7 2 bladed prop

ADDED: E-Flite Power 90 Brushless Motor (1800 watts max), Castle Creations ICE 80 HV Electronic Speed Control, 2 * Rhino 4S 14.4 volt 3.7Ah batteries (in series for 28.8 volts), Castle Creations BEC Pro, 15×7 3 bladed prop. (Now running a 16×8 3-bladed prop)

Twist 60 Weight Information with Power 90 and the 16×8 3-Bladed Prop

Dry Weight(fuse _ wing + power system): 2540g / 5.6 lb / 89.6 oz
Power 90 Brushless Motor: 450g / 1 lb  / 15.8 oz
Castle Creations Ice HV 80: 108g / .24l lb / 3.8 oz
Airtronics 92104 10-ch Rx: 15g / .03 lb / .53 oz
4 x Hitech HS-5625MG Servos: 240g / .53 lb / 8.5 oz
CC BEC Pro: 29g / .06 lb  / 1 oz

Battery Weight: 820g / 1.8lb / 29 oz
All Up Weight (AUW): 3360g / 7.4lb / 118.5 oz

In the pictures below you can see the results of the modifications. It is a much cleaner look but doesn’t have that ‘monster power plant’ look that the Saito had. Some things have to be given up if you don’t want to fly nitro.

Twist 60 with an eFlite Power 90 Brushless Motor

Twist 60 with Eflite Power 90 Closeup

One of the great things about Hangar 9 is that the Twist 60 came with the aluminum standoffs for the big brushless motor and the firewall was pre-drilled for these mounts as well as a standard nitro motor mount and they also include a tray that goes in the fuel tank area of the plane to hold the batteries.  This made the conversion very easy for the most part. The hardest part of the conversion was changing over the fuel tank bay into a battery, ESC and regulator bay and cleaning off as much oil off the model as possible so it could be re-born a dry flier.

I had to customize the included battery tray just a little bit for my needs, though I think most people will be able to figure it out without much brain effort. The forward firewall is pretty square, but you can add washers beneath the aluminum mounting posts for the brushless motor to put in some right thrust as need and correct for any pull-up/pull-down tendencies on throttle.

I’d never seen an electric Twist 60 on YouTube or elsewhere, so I wasn’t really what to expect for performance from plane. I can say I was happily surprised, I started off with a 15×7 3 bladed prop which had great performance, and with the 8s 3700mAh pack and varied throttle my flights were about 10 minutes, which I thought was pretty good. I’m used to electric helicopter flying times which are closer to 4 and a half to five minutes.

I did the conversion on a Sunday, tested the motor and batteries on Monday and did the first test flight Tuesday.  Below are the two videos from the Power 90 motor test with the 15×7 3-bladed prop, and the test flight on the same prop. One of my flying buds shot the video for me on Tuesday, I personally find that it’s hard to video and fly at the same time so some help is appreciated 😀

Twist 60 Electric Conversion Motor Test with 15×7 3 bladed prop.

Twist 60 Electric Conversion First Flight

After a bad landing recently that took out the 15×7 prop and motor bearings, I rebuilt the motor with ceramic bearings and switch to a 16×8 three-bladed prop.  The plane flies slower but has a lot more pulling power in vertical climb outs. It’s a better feeling propeller for this plane if you want slow and powerful flights.The video below is of a flight with the new bearings and the large propeller.

Twist 60 on Power 90 Brushless Motor with Ceramic Bearings and 16×8 propeller

Here are some Castle Creations logs from the plane with the new 16×8 3-bladed propeller showing current, power draw, RPM and usage. This first graph shows Current, Watts and RPM. The second graph shows voltage, current, Amp hours and throttle in for the same flight. The graphs show a peak values as follows – current of 66.3 amps at 33 volts reaching a maximum of 2003 Watts and a maximum RPM of 10568.

CC Graph Twist 60 With Power 90 Brushless Motor - Current, Watts, RPM

CC Graph Twist 60 With Power 90 Brushless Motor - Volts, Amps, mAh, Throttle

I don’t have any graph information for this setup with the 15×7 propeller, but at the next opportunity I will try to gather more information and include it in this post.

I hope you found this article useful or perhaps interesting. Feedback from my readers and viewers is one of my largest assets and helps to keep things interesting. I like to hear from folks if they have anything to say on the subjects I post about, so feel free to jump in and post a comment below.

Tags: brushless, CC BEC Pro, CC ICE HV 80, Plane, Radio Control, rc, twist 60