Primarily for general aviation discussion, but other aviation topics are also welcome.
#1799903
Pete L wrote:- BRS and multiple redundancy


You won't be at a height for BRS to be particularly useful in these. Helicopters spend most of their time at around 500-1000ft; not an ideal height to get a parachute out.

This thought that millennials will summon one with a phone app and hop about the city is absurd.

Re the pleasantness, note most of the test videos of these VTOLS are done without sound. They're also done in very low or nill wind. Watch a drone operate in a slight breeze; now scale that up and image you're inside it.
#1799941
riverrock wrote:I'm surprised you need a full new rating for it rather than differences training, as I expect that it will fly and handle just like a SEP, so the differences would be closer in equivalence to a variable speed prop or single power level control. It may be that EASA just need to catch up.

I don't think the licencing side is finalized yet. Our two FIs are the only certified electric aircraft pilots in the country. They got that on the back of a couple of days training at the factory. Mind you: they are really good pilots. The rating was issued as a separate paper; I have seen their actual papers yet.

Annoyingly, they can't instruct yet. We're still waiting on that.

We've been told to expect a proper course rather than a club evening like we had when learning Single Lever Control after converting a C172 to diesel some ten years ago. We don't have a time table for the course yet, but I'll be back with a report when we've taken it. I've done the computer-based training for the Alpha Electric on the Pipisterel web site. It was very much focused on "fuel" calculations and what to do in the event of a battery fire.
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#1811381
It's been a while without any news, but the members in our club recently got an update from the board.

Our two instructors are still the only two pilots in the country who are allowed to fly the Pipistrel Velis Electro. Contrary to what we've been told earlier, their rating is considered an exception. The Swedish CAA may consider issuing a few more such exceptions, but that's not really practical since our FIs are not allowed to instruct. And even without the travel restrictions, nobody would go to the factory and get the training.

Our authorities are now saying that they are considering new legislation sometime next year that will outline the requirements for an electric rating. We got the aircraft on Swedish registry in September thanks to a helpful authority, but their colleagues in the FCL department are obviously more cautioned / unhelpful / obnoxious: the choice of adjective depends on your point-of-view.

We have learned one thing, though: not only must the batteries be warmer than 0 degrees Celsius when charging (which we knew), they have to be warmer than 0 degrees at all times. We have a non-heated hangar, so we're trying out wrapping the cowling and the batteries behind the pilot in electric blankets. That method seems to keep the batteries ten degrees warmer than ambient temperature. We haven't (yet!) had any nights colder than minus ten, but that will happen. We'll see how the batteries can manage that.
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#1811633
Thank you akg1486,
We are all in your debt as you blaze the trail and share your experience.

Do you have any details of exactly why your FCL department is not producing what you need?
Whatever the reason - cautioned / unhelpful / obnoxious - the result's the same.
My own experience is that they are humans, often aviation enthusiasts, but with considerations or pressures not apparent to us (very occasionally downright unpleasant).

Are you plugged into Europe Air Sports?
#1811637
akg1486 wrote:We have learned one thing, though: not only must the batteries be warmer than 0 degrees Celsius when charging (which we knew), they have to be warmer than 0 degrees at all times. We have a non-heated hangar, so we're trying out wrapping the cowling and the batteries behind the pilot in electric blankets. That method seems to keep the batteries ten degrees warmer than ambient temperature. We haven't (yet!) had any nights colder than minus ten, but that will happen. We'll see how the batteries can manage that.

As a Tesla owner this is interesting! We have no info on sub-zero effects other than charge rate and range are both reduced with low ambient temperatures. In fact Norway was one of the very early markets for EVs.
What is it about the Pipistrel BMS that makes them suggest this? Incidentally we find a range reduction of something like 20% when below about 10C so keeping the battery warm is good!!
When it's all up and running I would love to have a flight :D
#1811695
malcolmfrost wrote:
akg1486 wrote:We have learned one thing, though: not only must the batteries be warmer than 0 degrees Celsius when charging (which we knew), they have to be warmer than 0 degrees at all times. We have a non-heated hangar, so we're trying out wrapping the cowling and the batteries behind the pilot in electric blankets. That method seems to keep the batteries ten degrees warmer than ambient temperature. We haven't (yet!) had any nights colder than minus ten, but that will happen. We'll see how the batteries can manage that.

As a Tesla owner this is interesting! We have no info on sub-zero effects other than charge rate and range are both reduced with low ambient temperatures. In fact Norway was one of the very early markets for EVs.
What is it about the Pipistrel BMS that makes them suggest this? Incidentally we find a range reduction of something like 20% when below about 10C so keeping the battery warm is good!!
When it's all up and running I would love to have a flight :D

We who are not deeply involved in the technical discussions with the supplier are asking ourselves more or less the same question: batteries in Tesla and other cars seem to be more resilient to cold temperature. As you say, Tesla is sold in Norway; in fact it's the best selling model car. And electric cars are popular in Sweden too, where it's also pretty cold.

I don't have a Tesla, but perhaps it uses some of its battery power to keep itself reasonably warm?

I've taken the CBT training on Pipistrel's web site for the Alpha Electro, which is the previous, non-certified, version. That training said that it was important to only charge above zero degrees. I don't think they compared with batteries in cars.

Another thing about the batteries that we know, and I may have mentioned that in an earlier post, is that Pipistrel won't take every single new battery generation. The reason is that new batteries require new certification of the whole aircraft. So every single improvement made in the battery industry won't be immediately available to Pipistrel Velis pilots and owners.
#1816758
A bit of good news and hopefully publicity: our club got a price from the Swedish Air Sport Association (or however it should be translated) for the acquisition of the Velis Electro. The price was 10.000 SEK, which is just under 900 GBP. The runner-up was a model aircraft club that cuts its grass runway using a solar powered and remotely controlled lawn mower.

Link (in Swedish, but I guess can be translated):
https://www.flygsport.se/Nyheter/Flygsp ... opris2020/

The Swedish CAA is still dragging its feet about the licensing, so at the moment the aircraft is really environmentally friendly since it doesn't fly. :(
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User avatar
By Tim Dawson
SkyDemon developer
#1816787
This sounds really fun to me. It’s a shame there’s so many buttons and controls to look after the battery; part of me had been hoping that the move to electric would get rid of most of the complexities of engine/fuel management.

In an electric, is it genuinely without risk to turn the engine off completely while airborne, making oneself into a glider, knowing you can turn it back on again? I can imagine making a game of seeing whether I could glide back to the airfield.
#1816788
akg1486 wrote:As you say, Tesla is sold in Norway; in fact it's the best selling model car.


Not currently (No pun intended)

Image

Hittil = YTD

Rob P
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#1816795
Tim Dawson wrote:In an electric, is it genuinely without risk to turn the engine off completely while airborne, making oneself into a glider, knowing you can turn it back on again?


IIRC in a Flying Reporter video he showed that when the throttle is set to idle, the prop stops completely; this was on the ground though.
#1816796
So drag would be minimised. That's quite a useful feature. Though whether this would hold good with the aircraft moving is the question.

Rob P
#1816801
From theory: a stationary prop incurs less drag than one which is windmilling.
From my Rotax Falke experience: when stationary, an unfeathered prop incurs far more drag than a feathered one.

Also from that experience: as the electric prop takes 90 secs or more to unfeather, I am loath to feather it unless absolutely confident that engine power will not be needed.
#1816802
allout wrote:From theory: a stationary prop incurs less drag than one which is windmilling.
From my Rotax Falke experience: when stationary, an unfeathered prop incurs far more drag than a feathered one.


Hardly unexpected. Isn't that rather the point of being able to feather the prop?

Rob P
#1816821
Tim Dawson wrote:This sounds really fun to me. It’s a shame there’s so many buttons and controls to look after the battery; part of me had been hoping that the move to electric would get rid of most of the complexities of engine/fuel management.

There are four switches, all of which shall be turned on (in a certain order) before starting taxi. The rest of the "buttons" in the picture in an earlier post are fuses. During flight, the pilot shall keep an eye out on battery health and otherwise just fly the aircraft. So much less to manage than in a piston aircraft.
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#1817096
Good news! The Swedish CAA has now completed the proposal for how SEP-pilots can be authorized to fly "electric, non-complex aircraft". Actors in the business (or even the general public) can submit comments until 7 January. There's no date for when the proposal becomes valid.

According to the proposal, the privilege to fly "electric, non-complex aircraft" will require a difference training for anyone who carries an SEP rating. The proposal covers in quite some details the theoretical and practical knowledge needed, but the practical part of the difference training will be a minimum of four lessons of no less than 40 minutes (block) each. To prolong the rating later, one needs at least three hours electric plus 40 minutes instruction. It's not clear if we will then need twelve "regular" hours (for the SEP) plus three electric hours. For my part it won't make a difference since I fly 30 hours per year. My SEP rating is valid until the end of July 2022, so I've got plenty of time.

I already fly the Pipistrel Virus, so I think the 4x40 minutes may be enough. (Our club/school may of course impose a different minimum with more than four lessons. We really don't want any accidents...) I think that pilots who only fly PA28/C172 may need a bit more to fly the Pipistrel Velis Electro simply because the airframes are so different. For members in our club, the logical route to the flying electric is to do the transition to the Virus first and then do the actual difference training. We already have an in-house "difference training" to go from PA28/C172 to the Pipistrel Virus. It's not mandated by law, but it's a really good idea to have as a club rule.

Our DTO obviously needs to apply for permission to give this training and can only do so once the proposal has been approved and is in force. I'm hoping that we can get going sometime in late spring, but that's my personal guess.

Keep watching this space if you're interested in further developments!
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