If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#11
|
|||
|
|||
FES&electric system batteries
Battery temperatures rise during use, it is part of what the pilot monitors during the launch. I've never seen or heard of battery temp being the limiting factor on power output. That is always motor temp in my experience.
What I've heard from Leo B-L is that the oldest highest use FES batteries are still charging to 99%. I'd love to hear more details on this 70% claim. |
#12
|
|||
|
|||
FES&electric system batteries
torstai 8. joulukuuta 2016 16.21.22 UTC+2 Tony kirjoitti:
What I've heard from Leo B-L is that the oldest highest use FES batteries are still charging to 99%. I'd love to hear more details on this 70% claim.. I'm a bit confused here. Are we talking about the voltage they charge to? You measure batter capacity by the amount of amperes you get. Obviously even older battery will have same voltage when charged full, but that does not say anything about capacity. If FES with 100% new battery gives you 60 minutes of level flight time (for example), 70% capacity battery would give you 42 minutes. |
#13
|
|||
|
|||
FES&electric system batteries
Well, since you mention that, I did once launch in a friend's ASW-24E
out of Kelly Air Park (7,050' MSL, 3,500' paved runway) on July 6, 2000. It took two attempts to get airborne and then a little nap of the earth flying to gain speed. Not for the faint of heart... The '24 is labeled an "E" but I think "T" would be more reasonable. On 12/7/2016 11:26 PM, Bruce Hoult wrote: On Thursday, December 8, 2016 at 2:21:34 AM UTC+3, Casey wrote: I've noticed that 13.5m FES are advertised as Front Engine Self Launchers and 15m are advertised as Front Engine Sustainers. I did here of a LAK 17b FES launch off asphalt. I wonder if the batteries heat up more from a 15m launching than a 13.5m? Or if the batteries heat up during prolong usage with either the 13.5m or 15m? Any glider with a sustainer can self-launch from a sufficiently long hard surface, with plenty of pressure in the tyre and a push start. Or, better, a tow to 100-120 km/h with a car. -- Dan, 5J |
#14
|
|||
|
|||
FES&electric system batteries
Dave Walsh, have you installed the Antares hard/soft upgrade yet for "charge plus". The software revision 6 provides for better charging and balancing of the batteries. There are two of us here in the US that are going to have this done in January. The factory is in the process of writing a new software version 7, which ads a number new functionalities.
One of the more interesting functionalities is internet access, which would allow the factory to access the US aircraft remotely and even perform software fixes and upgrades from Germany. On a side note; due to improved monitoring, version 7 will also make the recurring (normally annual) inspection have 3 years of validity, significantly reducing inspection costs for EASA certified aircraft. Version 7 is expected to be certified in the autumn of next year. |
#15
|
|||
|
|||
FES&electric system batteries
From the Lange website:
The life expectancy of the battery is decisively influenced by two factor the number of cycles and the natural aging process. The battery capacity decreases with increasing number of charging and discharging processes. The life expectancy of the battery is based on the latest findings with more than 4500 SAE cycles. One SAE cycle stands for full charging of the battery and a discharge to 20% of the capacity. Partial discharge corresponds only to an equivalent portion of a full cycle. After 4500 of these SAE cycles, the capacity of the battery has decreased to 80% of the initial state. For the pilot, this means that the battery allows a minimum of 10,800,000 risers before it is replaced. In practice, the natural aging of the batteries is more relevant. It is therefore recommended to change the batteries according to the latest findings at an average storage temperature of 20 ° C after approx. 20 years. Even then the battery capacity has decreased to 80% of the initial capacity. |
#16
|
|||
|
|||
FES&electric system batteries
At 15:45 08 December 2016, Tom TK wrote:
Dave Walsh, have you installed the Antares hard/soft upgrade yet for "charg= e plus". The software revision 6 provides for better charging and balancing= of the batteries. There are two of us here in the US that are going to hav= e this done in January. The factory is in the process of writing a new soft= ware version 7, which ads a number new functionalities.=20 One of the more interesting functionalities is internet access, which would= allow the factory to access the US aircraft remotely and even perform soft= ware fixes and upgrades from Germany. On a side note; due to improved monit= oring, version 7 will also make the recurring (normally annual) inspection = have 3 years of validity, significantly reducing inspection costs for EASA = certified aircraft. Version 7 is expected to be certified in the autumn of = next year.=20 This thread seems to be drifting into Antares territory; the Antares and FES (especially an Ultra-light FES self-launcher, i.e. the Silent Electro) are very different sailplanes. They are only similar in that electric power should get you to the nearest airfield/home. In theory the "electrics" option should be more reliable than the two stroke option, the downside is the much reduced range of current "electric" systems. In this regard FES is a much better "get you home" option than a self-launcher. To answer the previous post I have software version 6.0 ("Charge Plus"); it was already installed when I bought the A/C two years ago. It allows you to charge the batteries to about 118-120%; I don't actually understand this (I'm a biochemist not an electrical engineer) but what it means is that I can launch from Sisteron (French Alps 1700 ft elevation, ~30C), climb to about 5000ft (about the limit before the engine temperature gets into the red), stow the engine and have about 60% battery power remaining. If you don't use the "charge plus" feature the remaining battery power is about 45-50%. These figures are for 10 year old batteries, with a total of 700 flight hours. Looking at my considerable file of invoices I see that the upgrade to software 6.0 was not cheap. I am told that one of the big advantages of version 6.0 is that it prevents catastrophic total discharge of the batteries which can happen through operator error (for instance putting the A/C away, going on holiday, whilst accidentally leaving the radio switched on). This, I am told, can be a very, very expensive mistake as it requires replacement of all 72 battery cells. Version 6.0 "Charge Plus" has some limitations; the batteries once charged to 120% have to be used, so the A/C has to be rigged and the engine to be ground run to reduce power back to 100%. This can take quite some time! (There may be some other way to do this buried in the software, but as all my documentation is in German, I have never tried it). Also if you use "Charge Plus" immediately before flight some of the electronics and the batteries will be hot. I have heard various opinions on whether this is a significant factor. I avoid this by running Charge Plus overnight. Here in EASA land I am not sure that the extended inspection periods you mention are relevant? On your side of the pond Dave Nadler (an ex Antares owner) might be a good source of information? Dave Walsh |
#17
|
|||
|
|||
FES&electric system batteries
On Thursday, December 8, 2016 at 10:45:29 AM UTC-5, Tom (TK) wrote:
...One of the more interesting functionalities is internet access, which would allow the factory to access the US aircraft remotely and even perform software fixes and upgrades from Germany. Non-USA Antares have had this facility from beginning. All USA Antares, including yours, already have this capability. I wrote and installed the facilities required for USA many years ago ;-) Unfortunately its not so useful in practice. Poor internet connectivity at many sites makes it dodgy. Do you want a remote update over a poor connection killing the machine? For this and other reasons, you always need a qualified tech on site for updates, which makes this not so useful. For diagnostics, better is diagnostic dump to USB. USA Antares, including yours, have had this for years. You may guess who wrote and installed it ;-) See ya, Dave |
#18
|
|||
|
|||
FES&electric system batteries
Interesting that while current Kokam batteries for FES cost 8000 euros (2000eur/kWh), at the same time Tesla is building batteries costing under 200 eur/kWh. Assembling FES battery with new Tesla cells would cost one tenth, even doubling or tripling that would still keep it quite affordable. Why use so expensive battery?
|
#19
|
|||
|
|||
FES&electric system batteries
On Thursday, 23 February 2017 13:27:10 UTC+2, krasw wrote:
Why use so expensive battery? Because we all know that money makes aircraft fly. If we don't pay lots of money things won't fly. |
#20
|
|||
|
|||
FES&electric system batteries
On Thursday, February 23, 2017 at 5:27:10 AM UTC-6, krasw wrote:
Interesting that while current Kokam batteries for FES cost 8000 euros (2000eur/kWh), at the same time Tesla is building batteries costing under 200 eur/kWh. Assembling FES battery with new Tesla cells would cost one tenth, even doubling or tripling that would still keep it quite affordable. Why use so expensive battery? I think this is where Bob K or Darryl R inserts pictures of Flaming Tesslas.... |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
ASW24 - electric valve system | Norbert Gulczynski | Soaring | 1 | January 25th 15 02:13 PM |
AGM Batteries | Dave Anderer | Owning | 13 | March 29th 08 08:38 PM |
System Operation of Aircraft System | [email protected] | Instrument Flight Rules | 1 | October 12th 07 06:50 AM |
2-Batteries | [email protected] | Soaring | 69 | January 4th 07 05:09 AM |
160 new batteries | Mal | Soaring | 0 | October 27th 06 11:36 AM |