$1 billion BMS Ooops...

2G wrote on 3/7/2021 9:06 PM:
On Sunday, March 7, 2021 at 8:52:23 PM UTC-8, Eric Greenwell wrote:
2G wrote on 3/7/2021 8:30 PM:
On Thursday, March 4, 2021 at 1:55:30 PM UTC-8, Kenn Sebesta wrote:
A hybrid system with a gas engine wouldn't have the pucker factor associated with starting a
gas powered motorglider to avoid a landing: if the hybrid engine doesn't start, it just means
your potential retrieve distance is shorter, instead of an imminent landing.
I'll wade in here with some experience. Top Flight, a Boston startup specializing in hybrid propulsion systems, spend over half a decade developing their power unit. The hardest part for them was developing a unit which was reliable. Motors don't like vibration and they don't like heat. Combine the two together and the motor is not long for this world. It took a lot more R&D than anyone expected to make a lightweight package which could survive..

I would not expect anyone to be deploying this technology anytime soon.. If and when it is commercialized, it will be useful for ferry flights of electric aircraft. For any use which requires permanent installation, you're probably better having it drive the propeller directly.

eGliders, I sense a tone here which is reminiscent of discussions about finally putting the 2-33 to rest. The US is no longer the forefront of light aviation, so we need to look east to see what the trends are. We know that leading glider manufacturers are racing to bring eGliders to market.. A gentleman who works on glider competition rules noted this summer that glider records are falling left and right to eGliders. There is a growing group of amateurs who are pulling their engines out of their gas self-launchers and replacing them with electric (If you'd like to be a part of this group, DM me). The future was yesterday, but like any future it doesn't arrive at all places at once.

Why don't you start by naming JUST ONE that replaced an ICE with an electric.

Tom

Hank Nixon.
--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
And what was the glider?

Hank has posted about the glider a number of times on RAS. Search for "Nixon", or look in the
thread "What is involved regulation wise adding an electric motor to a glider?" Here is are
some details from Hank:

Some data from first hand experience:
ASW-24E converted to electric from 2 cycle Rotax gas.
Power system including all items is right at 100 lb added to pure sailplane airframe weight.
This is a pylon mounted retractable system.
Battery is 120 volt,4.9 kwh lithium ion weighing 60 lb.
Climb rate at 160 amps is 300 ft/minute. Actual power delivered is about 16kw.
Climb rate at 230 amps is 500 ft/minute. Actual power delivered is about 23kw at this time
Your cost estimate is a bit less than1/2 what it would require for parts, not including items
required to do the airframe conversion and assuming the person doing this can fabricate
required items, engineer and wire the system, design and construct the prop, etc.
This assumes perfect efficiency and nothing destroyed or scrapped going through the learning
process. Of those I am aware of that have done ,or are doing this, nobody has had that good
fortune.
FWIW
UH

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1