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Electric / hybrid aircraft propulsion (NOT cars)

Having talked to several people who are using the Velis IMO you need to knock around 10% to 15% off of that 50mins range.
I would also be suspicious of what remains being available at the quoted 98kt cruise speed. It might be available at an ECO speed nearer 60kts.
However, even if the figures quoted by Pipistrel are correct you have a without reserve range of less than 50nm. That’s 25nm there and 25nm back.
Unless of course you can recharge at your destination airport. Not many airports have recharging points, but if you can carry your own connection lead (about 5kg) and if you find a willing club who will allow you to plug into their system you will be able to recharge wholly in 20 to 25 hours.
If your destination airport has a charger like Peter photographed at Shoreham (it looks like you still have to bring your own lead,) if you have type 2 both ends (not domestic and heavier) you can probably recharge in about 7 or 8 hours. If you only have the domestic cable a full charge can take around 16hours.
There are fast chargers which have their own cables and connectors which can reduce charging time to less than an hour but I I haven’t seen any of these ready for aircraft use. Has anybody?
IMHO gliding towing would be a possible mission but there it would have to compete price wise with ULMs such as the Icarus.
Otherwise it’s only useful mission is circuits training.

France

Or recuperate the energy by having the airstream turn your prop, for even steeper descents.

Berlin, Germany

I have a feeling I may have mentioned it in this thread, but I’d love an electric glider tug. I could tow the glider to release height, and with a folding or feathering prop simply stop the motor from turning and glide back, with no worries about engine temperatures etc. and have the ability to instantly start the prop turning should I misjudge the glide back. More neighbourly (less noise, especially once the prop stops turning), and a lot more energy efficient because once the glider is released, the electric tug can just glide itself rather than a powered descent. And no need to deal with filling up with liquid fuel, just plug it in at the end of the day and it’ll be ready for the next day’s operation when it starts.

The real snag is of course the price. Any of these electric LSAs or small certified aircraft are massively expensive compared to an old 1940s Auster J/1. The price delta buys vast quantities of avgas. The other snag is that it’ll effectively be a single use aircraft (towing and local bimbles), the Auster can do this but also go on trips to the UK/Ireland (full tanks will get me anywhere within the UK).

Last Edited by alioth at 22 Mar 12:57
Andreas IOM

The interesting bit is not that one can build an electric plane. The 3 phase motor and the inverter are easy. It is down to carrying the batteries…

It is that some schools appear to be paying ~200k for these things which, it now seems clear, cannot be flown any useful distance away from the airport, so are not suitable for most PPL training. You could fly circuits in them but as soon as you are done with that (maybe 25% of a PPL?) you need to convert to some avgas burner and do the other 75% in that.

I wonder if Pipistrel are doing some heavy subsidies? In 2001, a local school was looking to buy 3 x C172. The UK disti offered them amazing pricing, something like 150k for 1st one, 120k for 2nd one, 100k for 3rd one. Really deep discounts. Yet a C172 could be sold anywhere.

Often, giving away products is cheaper than advertising. The problem with advertising is that everybody can see it as such and assumes it will be biased. But if you sell some electric plane at a 75% discount, it gets you massive media coverage. All the rags are desperate for anything to publish, anything at all relating to GA, and this is a gift from heaven.

Administrator
Shoreham EGKA, United Kingdom

Airborne_Again wrote:

The Velis Electro must be seen as a technology demonstrator

The previous experimental version, certainly. However, this is the certified version. It’s supposed to be used for “certified” stuff An honest look at this, and it’s obvious that the only thing the aircraft can be used for, is as a demonstrator that shows electric flight is possible. The certification is more of a sales gimmick, since there’s nothing practical it can be use for, not even training, and there is no need to certify it to come to that conclusion. It’s been an exercise for EASA (and Pipistrel) perhaps, put down all the ground work for certification of electric planes.

Electric aircraft is something that fits in the UL/experimental world. It’s something for homebuilders to experiment and fiddle with, and there’s several dozens of aircraft to chose from. Perhaps in air sports they would also be a thing, some way or the other, gliders being the obvious, but far from the only. The certified world is about payload and endurance exclusively, and this requires an increase in energy density that current Li ion technology will never achieve.

The elephant is the circulation
ENVA ENOP ENMO, Norway

The Velis Electro must be seen as a technology demonstrator — not as a viable aircraft. Not primarily because of endurance but because of weight limitations.

ESKC (Uppsala/Sundbro), Sweden

In the last number of Flynytt (Norwegian GA magazine) there’s an article about the project of the Danish Air Force. The last 2 years they have tested the Velis Electro to see if it’s suitable for training in particular, but also other other thing the air force would use a GA aircraft for. The project is now ended, and the conclusion is rather funny: They didn’t find it suitable for any practical purpose whatsoever It was good at one thing. It was better than other trainers for soaring. During one flight they managed to stay airborne for 1h 53 minutes. The engine was running all the time, because at 6000 feet they were afraid the temperature of the batteries would get too low (which IMO is just nonsense, but that’s for the PIC to decide anyway).

I have tried the Velis Electro. It flies just fine. A nice aircraft. Feels like a underpowered and heavy Alphatrainer. In all honesty, “heavy and underpowered”, is the feeling you get when comparing any UL with an “identical” LSA. Funny thing, with two grown ups, an LSA and this Velis Electro has about the same endurance also. In some cases, the Velis has more.

The elephant is the circulation
ENVA ENOP ENMO, Norway

From Sweden, so with impeccable credentials!

(from FTN, a UK flight training trade rag)

impractical for anything other than flight training adjacent to their home airfield

Administrator
Shoreham EGKA, United Kingdom

The Velis Electro.

It flies well, with pretty significant issues. It is funny in how they bend the normal definitions of stuff like “reserve”



A new term: “VFR reserve” → “reserve within a specific airport” → 10 mins is OK. 40 min recharge which is not bad. But the airport installed a 1 MW supply.

Battery degradation from 100% to zero in 500hrs, but some degraded a lot faster (warranty change). The battery costs 20k and that (20k/500) is the dominant cost. The electricity cost at the location of the flight is close to zero (€1 for a 40 min fight; obviously nonsensically subsidised).

Battery needs to be above +5C to be usable, so a preheat capability is unavoidable. This was Sweden and a heated hangar is mandatory.

No cockpit heater

Administrator
Shoreham EGKA, United Kingdom

Here’s an interesting article about an electric aircraft in today’s NYT (should not be behind paywall, as I can ‘share’ articles as a subscriber).

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