Is Now the Time for Electric Ultralights?

 The biggest use of ultralight aircraft is to enjoy flight. To that end, is now the right time for an electric ultralight aircraft? I've been there and done that and want to share my history with you.

My History with Electric Ultralights

I've designed and flown electric aircraft. I threw a lot of money into this one, which featured a carbon fiber fuselage and wing. It is called "SkyDock". I developed it with a gas engine as well.

A couple of years before that, I adapted an electric motor to a classic Belite ultralight.

To help answer the question:

1. Ultralights are flown for fun; and electric flight is super fun!
2. Electric motors are available with incredible value and excellent power;
3. The best batteries ever are now available;
4. U.S. ultralight law allows individuals to do this experimentation easily;
5. Even a company or two (eg: Chip Erwin and Merlin) are publicly showing their work with electric ultralights.

Electric Installations:

Consider a single vs dual motor installation. The SkyDock was setup with two motors, while I flew the Belite with one motor. One of my customers used a very interesting single motor design for his converted UltraCub.

Want to see the electric motors on Skydock doing their thing?:

And even more details of how the Skydock Electric motor installation was designed:

Is Now the Time for Electric Ultralights?

Yes, it is.

• Electric flight in ultralights is proven by myself and others.
• Batteries can produce acceptable flight times for ultralight aviation.
• FAR 103 and Experimental rules allow it.
• Bonus: Electric motors are less expensive than gas motors. (Although offset by battery acquisition costs.)
• Electric flight has a unique sound signature, better and different than any gas motor.  It's just the prop and the airframe, no combustion sounds!

For further exploration:

I recommend you join this Facebook group, run by Bill Esker:

Ultra-electric: do it yourself electric ultralight conversion | Groups | Facebook

The Curious In-Flight Engine Failure of N3748 in Alabama

I was flying N3748, the very first Chipper 2, and I was in cruise, home-bound from a successful Sun-N-Fun in a stiff headwind. One moment, a very choppy but normal aircraft experience. The exact next moment, the propeller was dead-still, and had come to that dead-still position in just one or two revolutions of the crankshaft. It was the kind of violent engine stoppage that screams that all is not well, and that your 'full and undivided' attention needs to be on resolving the emergency of the moment. I looked down, as I scanned the area for a place for an immediate dead stick emergency landing.

I took some critique recently for editing and posting a YouTube video which was described as click-bait. This article is not that; I will tell you exactly what happened, how I responded, and what we found in the engine. I have witnesses who were there, and I have photos of the aftermath of the engine. I won't belabor this story; I've kept this as a short and easy read.

Sun-N-Fun, 2018

But the first order of business for this curious tale is to backup just a few days, to Sun-N-Fun, 2018. I was there with Chipper 2, and it was a success story. Chipper 2 N3748 performed without flaw, showing outstanding takeoff and landing capabilities.

To my delight, it even got the cover of General Aviation News. Describing the airplane as "Chipper in Paradise", it helped fuel good PR, sales, and momentum for Chipper Aerospace, my company.

Engine Changes

Chipper had started out as a two place aircraft project. I originally saw it as an airframe powered by a 60HP engine. To that end, I'd purchased a used Japanese HKS 700e engine, installed it on the plane, and discovered that the engine needed an overhaul. So Chipper never flew with 60HP.

After much consideration, I purchased a new Rotax 912UL, an 80HP engine, brand and spanking new. Everyone who flew it loved it. It did not disappoint at 80HP, and was bucking the trend that light sport aircraft needed to have 100HP engines. Hogwash; I showed them otherwise and proved it.

Yet there was that lust for power, for an improvement in ground roll, for an increased angle of climb. Without changing to yet another engine, the only way I could squeeze more performance out of my Rotax was to upgrade it using an aftermarket kit. When the engine had about 150 hours of use on it, I decided to purchase an engine upgrade from Edge Performance. 

The kit was ordered and received. It was principally installed by a local A&P mechanic. I never touched anything; I'm not an engine guy.

The upgraded engine on N3748 was what I took and showed in Florida.

And its performance was fairly phenomenal. Here's video proof, which I took in-cockpit while taking off in front of a crowd at Sun-N-Fun:

The Flight Home

This is what I remember about the flight home. First of all, the wind, blowing on the nose of the airplane, making every effort to slow my progress.  I tried low altitudes. That increased airspeed, at the expense of bitter, angry jostling of the airframe. I tried high altitudes. A smoother ride, at the expense of speed. For a long while, I was just a few hundred feet off the Alabama forests, with no landing options but with faster speeds. For whatever reason, before I reached Evergreen, Alabama, I climbed up several thousand feet.

When it Gets Real

While in cruise at approximately 4000' altitude, I experienced a sudden and complete loss of power of N3748. One moment all was well, and the next moment, the propeller was fully stopped. My body told me that a restart was not possible due to the shaking experienced while it shut down. Perhaps I touched the starter; perhaps I checked fuel.  I am not certain and I knew it didn't matter. The engine had failed.

I had been traveling over endless miles of forest, with low or non-existent options for emergency landings. I knew I had been playing my odds wrong (I'm always looking for emergency locations.)

This time, I looked straight down, and I realized that I was over the midpoint of the east-west runway of KGZH, Evergreen Regional Airport (AKA Middleton Field). Having already established glide, I made a left turn to reverse course and establish a dead-stick pattern downwind. I looked up the frequency for the airport, and quickly dialed into my radio.

I said: "Evergreen, are you there?"

An angel said back: "This is Evergreen Regional, I read you."

I said: "Evergreen, I am dead-stick overhead your airport now, landing. Can you observe my landing?" I don't remember using the emergency word, but I know that my language conveyed emergency, urgency, and fear, all in one.

The angel said: "Wilco, I'll hop in the truck and see you on the ground."

I think I got all that done while on downwind. A little voice in my hide was nagging me on the irony of dead-sticking into a huge paved airport, and then ending up short on final. That would be an insult wrapped in a tragedy inside of an emergency. I didn't want that to happen.

Adjusting glide, I added flaps and also added a little droop aileron. I listened to the electric linear motors driving the flaps and droop mechanism. I listened to the air flowing around the aircraft.

I turned base.

I turned final.

I passed over the threshold, probably 100+ feet off the ground.

I touched down. It was a pretty good landing. I was one-third down the runway, with a thousand feet behind me and two or three thousand ahead of me.

I rolled to a stop, and off to my right the Angel drove up in a pickup truck.

Tears / crying, but I was alive and unhurt.

Engine Teardown

Let's cut straight to the cause: the engine failure was caused by a failure of and/or improper installation of a clip. The engine had clearly been operating for some time with the failed condition.

Aftermath

After the teardown, the plane was loaded into a rental truck, and I drove it home. It eventually was repaired and received a couple more upgrades, before I flew it to Alaska, and it was destroyed after another engine failure. (Another story for another time.)

Curious Questions

1) Why did the engine fail when I was mid-field over an airport?

2) Why did I upgrade the engine in the first place?

3) What could have been done to prevent this from happening?

The Angel

The airport manager was a wonderful woman, whose name was Terri. She was emotionally and resource-wise helpful to me and spared no effort to make my stay in Evergreen comfortable. I got the use of the airport car, of course. :-)

 Friends, there's some honesty buried in here as it relates to experimental aircraft. Read it all and share freely.

Squawk & Resolutions on N318KW

1. Brake Pedals in-op. Resolution: add 1" spacer to brake pedal. Permanent solution; works well.
2. One of the tires is low on air. Resolution: add air.
3. Right brake in-op. Resolution: bleed brakes.
4. Right brake still in-op, next day. Resolution: bleed brakes using the correct procedure after reviewing youtube video on the topic.
5. Brake line leaks: Resolution: tighten fittings.
6. Braking action still poor: Resolution: brake fluid probably on brake pads / discs. Use brakes to refinish pads. Braking action now OK. Note: I have dual caliper brakes and they are mandatory for large tires. A single caliper brake wouldn't work.
7. Elevator range of motion incorrect. Resolution: adjust all fittings so that up and down are balanced. There are several points of adjustment affecting this from the push-pull fittings, the location of the push-pull collars, inside-cabin adjustments, etc.
8. One of the tires is low on air. Resolution: add air.
9. Discovered critical bolt installed upside down in elevator reverser fitting. Bolt also was loose with standard hex nut. Loss of bolt would cause loss of control. Resolution: install bolt correctly, with nyLoc nut. Death averted. Question: how did everyone miss this?
10. On first flight, aircraft rolls left tendency. Resolution: adjust stick position via pushrod to aileron mixer.
11. On first flight, aircraft has heavy elevator response. Resolution: add fixed trim tabs to elevator. Final resolution: in-flight adjustable elevator trim tab.
12. In cruise, aircraft yaws left. Resolution: add trim tab to left aileron.
13. On takeoff, quick application of full power causes aircraft to turn left REALLY QUICKLY. Resolutions: a) improve pilot skill b) don't do that c) resolve to use less powerful engine d) use full!!!!! right rudder. In the spirit of Draco, for crying out loud, your skill level needs to match the airplane and the powerplant. You can't jump into this airplane and expect it to fly you. You will have to fly it while taking off and even in ground roll, or you'll have an accident.
14. Long main gear is chattering. Potential resolutions: add shock absorbers, and yes, I am planning to do this. Meanwhile, every landing is best performed to 3 point and full stall. Don't even consider a wheel landing. I will follow up with a builder alert after I install shock absorbers.
15. Oil leak as evidenced by small puddle on floor of hangar. Resolution: temperature sensor was installed without teflon tape.
16. Oil leak as evidenced by even smaller puddle on floor of hangar. Resolution: pressure sensor was installed without teflon tape.
17. Airspeed Indicator possibly not functional at low airspeeds, due to high angle of attack. Resolution: smile and enjoy the slow airspeeds. Learn how to fly using butt feedback, not instrument feedback. This airplane will love you, if you give it the chance.
18. Yaw oscillation in cruise. This happens only when: a) cruise speed b) feet not on rudder pedals c) turbulence. The plane will *slowly* start to yaw left and then right, kind of like an old fashioned v-tail bonanza. Resolution: a) keep feet on rudder pedals -or- b) add rudder tension spring. You may notice that in yesterday's video posted here, there was no evidence of this. Seriously, the rudder tension spring is the solution.
19. Pitch oscillation in turbulence. This never happened in N3748, but I have seen some evidence here in N318KW. The reason is simple: the elevator on this plane is heavier, so that a gust acceleration upward causes the mass of the elevator to go downward. This is a precursor to flutter. Resolution: I will adding mass balance weights to the elevator. I will follow up with a builder alert on Chipper Builder.
20. Out of an abundance of caution, I am planning to add vertical stabilizer flying wires, which N3748 had but N318KW does not. Resolution: add flying wires. I will follow up with a builder alert on Chipper Builder.
21. Windshield cracked. Resolution: performed airworthy windshield repair. Longer term resolution: under thought now.
22. One of the tires is low on air. Resolution: add air.
23. Tailwheel steering in-op. Everything you see me doing to date has been done without any tailwheel steering whatsoever. I've gotten OK learning to feel the airplane, rudder, brakes, power and to taxi with confidence, without a steerable tailwheel. Resolution: need to install tailwheel steering.?!

Flaps, Fire, and Fatalities

 "Flaps, Fires and Fatalities, of sorts".

Fire burned our facility 2.5 years ago, destroying the business. Chipper 2 N318KW survived because it was out at the hangar, but the flap extensions were in-town. They were recovered from the fire debris and have been sitting around ever since. They are still covered with soot.

I want to tell you about installing them yesterday, but first I want to tell you a little more about the fire. Back up your calendar to June, 2019. Before Covid.

Kathy Wiebe and I had gone out to eat, it had been a great meal and a great date night, our Friday evening tradition We were sitting in bed, late on a Friday evening. It was normality. It was about 11:15 and my cell phone showed an incoming call.

"This is the Wichita Police Department... There's been a fire at your facility. Someone needs to come."

Kathy and I threw on clothes and rushed to our building. It was firefighting on full display; 20 emergency vehicles; firefighters walking around mopping up details; rolling hoses.

Eventually, I went to the back of the facility and talked with a fire commander. I think we discussed possible fire origin points (the stupid CNC dust collector, of course) and I thought about the irony that one of our CNC operators was a recently retired firefighter.

And then I thought about our shop cats. I asked the fireman whether they'd been seen. He motioned to the ground, directly by where we were standing. A lifeless body of a cat was on the ground. No motion. Sooted. Dead.

I broke into hacking sobs, tears.

Back to those flap extensions.

Yesterday, I installed them for the first time. I have chosen to fly with them, covered with soot, and who knows, I may never paint them. They are a reminder of what was, how I felt, and also how far from then to now I've come. They provide an entry point of discussion for anyone who looks at the airplane -- why are those dirty pieces of s*** attached to that gorgeous airframe? And then I can tell the story, of which this narrative is a small part.