# Harbour Air commits to going electric

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#### TFF

##### Well-Known Member
I learned I like winding a watch. The one that I have with the display back is fun to watch run; all those little parts fitting together working. They are all put together by hand no matter the brand or cost. They are more fragile and I still dont wear a watch at work, because it would get destrouyed, but I go home and put one on. Just plane telling time reminds me of work. But I also have a biplane project so that might explane it more.

Unless you have your own acre of solar panels, elelctric planes will not be cheap. That in its self would not be cheap. Electric would be cheap now with the way electricity is priced. Everyone is assuming it will stay that way. In the end the price per unit will go up and up because that is how companies make money. And no one will get away from that reality.

#### BBerson

##### Well-Known Member
HBA Supporter
$11,000 for electric is still a lot compared with say$900 for a cool sounding Briggs.

#### Tiger Tim

##### Well-Known Member
You could put in a big speaker so that it actually SOUNDED like an Eindecker. ;-)
Just stick some baseball cards in the prop arc!

##### Well-Known Member
I don't think a $900 Briggs is flight ready! I have about$4000 in a used Rotax 503 setup. A comparable electric system is $11K I guess....if you buy it "turn key". You wouldn't need a big solar array to keep a lithium battery charged as long as you're not flying more than an hour a week or so. I'm lucky to fly an hour a month. But for some applications I can see the value of an electric system. If you fly 50 hours per year that amounts to maybe$1100 in fuel, oil, and maintenance fund. Ten years of electric flying could pay for itself.

#### BBerson

##### Well-Known Member
HBA Supporter
I think batteries only last about 5 years if used or not. That is a big expense when flown 12 hours a year like we do.

#### markaeric

##### Well-Known Member
A $900 Briggs, or any stock Briggs for that matter, isn't putting out the same power as a 503. There's a handful of 40kW (peak.. more like 30 continuous) electric motors, mostly from CZ and the rest from China. Fairly inexpensive at$1-2k. Bigger than that and choices start to slim. Controllers are roughly half the cost of the motor. 100lbs of batteries will give you ~4.4 - 9kWh depending on chemistry at a cost of around \$4k new. So if you run it at 30kW for the entire flight, that provides an underwhelming endurance of less than 9 to 18 minutes (at 100% discharge). So the system weighs more than a 503, and you can't fly as long as you could with 5gal of gas. Not very compelling. With such crappy power density of batteries, you really need an efficient airframe that can fly with minimal power.

##### Well-Known Member
So if you run it at 30kW for the entire flight, that provides an underwhelming endurance of less than 9 to 18 minutes (at 100% discharge). So the system weighs more than a 503, and you can't fly as long as you could with 5gal of gas. Not very compelling. With such crappy power density of batteries, you really need an efficient airframe that can fly with minimal power.
Such a Debbie Downer!

#### markaeric

##### Well-Known Member
lol. What I meant to say was "So if you run it at 30kW for the entire flight, that provides an OVERwhelming endurance of less than 9 to 18 minutes"

#### tspear

##### Well-Known Member
Will still take X hp to cruise at 120 knots whether delivered by electric motor or IC engine.
Actually electric engines should require significantly less HP for the same cruise; the reason is both a reduced frontal area and also significantly reduced cooling, air intake, exhaust drag.
The problem I see is the Beaver is so draggy of an airframe; I am not sure how much power is "wasted" on these effects will have a material effect.

Tim

#### rv6ejguy

##### Well-Known Member
Actually electric engines should require significantly less HP for the same cruise; the reason is both a reduced frontal area and also significantly reduced cooling, air intake, exhaust drag.
The problem I see is the Beaver is so draggy of an airframe; I am not sure how much power is "wasted" on these effects will have a material effect.

Tim
Of course cleaning up the front of the Beaver with an electric motor would reduce the power requirements for the same TAS but that wasn't the point of my post which addressed the belief that electric motor hp was somehow more than gasoline engine hp.

The slightly lower drag won't have a material effect on the range of an electric Beaver making it useful for anything more than short hops with current battery technology.

#### tspear

##### Well-Known Member
Of course cleaning up the front of the Beaver with an electric motor would reduce the power requirements for the same TAS but that wasn't the point of my post which addressed the belief that electric motor hp was somehow more than gasoline engine hp.

The slightly lower drag won't have a material effect on the range of an electric Beaver making it useful for anything more than short hops with current battery technology.
Agree.

Tim