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PostPosted: Thu May 18, 2006 8:15 am
by darkhorse

PostPosted: Thu May 18, 2006 11:59 am
by Chappy
OK, chill. Here's what's happening from my end:

I spent some time looking at this whole project idea several months ago. I talked with several other engineers and an old friend that is the leading electric model aircrafter in the whole Washington, DC area (he has built well over 300 battery-electric model aircraft in the last 5-6 years). My research started with the E-Tek motor - actually, it was the stimulus to get me thinking about an Electric Lazair. I came to these conclusions as it relates to my requirements.

1. The E-Teks (if you used 2) are just too big and heavy for what I wanted on my Lazair. I want to keep my Lazair a twin engine (twin motor) aircraft, and keep the weight under control.

2. Large enough motors (brushless multipole outrunners) are just now appearing in the model aircraft market that would be MUCH more suitable for my Lazair than the E-tek or similar. They are incredibly small, light AND efficient! They also require special, expensive controllers, but they will efficiently drive a prop directly without the need for a prop speed reduction unit, which the E-Teks would need.

3. I was looking at Nmhd batteries, perhaps from wrecked Hybrid autos, as an economical battery source, but they would still be very expensive and somewhat heavy. Lead acid batteries are just too heavy for me, and besides, they take sooo long to recharge. Li-ion batteries are now available in the model airplane market. They are worlds ahead of anything else you or I could buy anywhere else, because the model aircraft market is so huge, which is bringing their cost down like mad. But - they are still not cheap, they require expensive chargers and controllers, and are kind of ill tempered. If you fast charge them to the extreme, you severely reduce the number of time you can recharge them. If you over discharge them just once, they can be ruined. In other words, batteries are STILL THE WEAK LINK in the whole project, but not to the extreme that they were even just two years ago.

The model aircraft market goes through a motor and/or battery revolution every few years. Personally, I've decided to wait this one out. Within just another couple years, I predict that utilizing off the shelf hardware from the model aircraft market will allow most anyone to electrify their Lazair, if they so chose. I think it's possible right now, if you are willing to search out the bleeding edge products out there, and match them up intelligently, and be willing to foot the bill, which right now will be rather onerous. I have neither the time, nor money, to devote to the project right now. My house building project will keep me quite busy and tapped out for the rest of this year.

That said, there is at least one person out there that I know of that is very seriously pursuing an electric Lazair development project. He does NOT want to be identified, so don't bother asking. When he's got it working, I'm sure he'll let the rest of us know. I can barely keep from bugging him myself, but unfortunately I'm afraid it's just going to be too expensive for me to justify doing anyway! But maybe not, so I'll wait and see!


PS. If you Google electric model aircraft and brushless model motors, you will be overwhelmed with stuff to look at. There are even sites to help you build your own motors.