![]() |
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 |
|
#1
|
|||
|
|||
![]()
On Wednesday, September 11, 2019 at 7:15:06 AM UTC-4, Jim White wrote:
At 00:23 11 September 2019, 2G wrote: ? The only way to know with any certainty the energy content of a battery i= s to do a discharge test. This can be done very easily with an FES - you Coulumb counter should do it. Count the coulumbs in and out. Jim A Coulomb counter counts electrons, not energy (Coulombs times voltage) - some energy is lost to internal resistance, thus the output voltage is lower.. Also some Coulombs are lost to internal self-discharge. The energy coming out is always less than the energy going in. That said, as long as the battery is behaving consistently these losses are predictable, albeit variable with time since charge, temperature, discharge rate, etc. And the prediction will be wrong once some deterioration happens inside the battery. |
#2
|
|||
|
|||
![]()
On Wednesday, September 11, 2019 at 5:19:03 AM UTC-7, wrote:
On Wednesday, September 11, 2019 at 7:15:06 AM UTC-4, Jim White wrote: At 00:23 11 September 2019, 2G wrote: ? The only way to know with any certainty the energy content of a battery i= s to do a discharge test. This can be done very easily with an FES - you Coulumb counter should do it. Count the coulumbs in and out. Jim A Coulomb counter counts electrons, not energy (Coulombs times voltage) - some energy is lost to internal resistance, thus the output voltage is lower. Also some Coulombs are lost to internal self-discharge. The energy coming out is always less than the energy going in. That said, as long as the battery is behaving consistently these losses are predictable, albeit variable with time since charge, temperature, discharge rate, etc. And the prediction will be wrong once some deterioration happens inside the battery. And the device would have to be calibrated anyhow by doing a discharge test.. That said, it would be useful to have an accurate battery fuel gauge in the cockpit. I would not, however, recommend that the average glider pilot install any instrument that requires modifying high voltage/current circuitry. Doing a discharge test, on the other hand, only requires a stop watch. Tom |
#3
|
|||
|
|||
![]()
Kawa has been a beta-tester for a novel engine installation in the GP14. It was always going to be fallible.
Reading his account, he was not complacently relying on the motor to start. He started it where he thought he had acceptable landing options, and after it failed to start he continued to fly with what he thought were acceptable landing options. He attempted to land in what he had judged to be an acceptable if difficult field, and unfortunately it turned out not to be. If as he says this was his first field landing accident after decades of cross country flying in hazardous terrain in the heat of competition he is not doing too badly. |
#4
|
|||
|
|||
![]() |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Avro Tudor pics 2 [04/13] - Avro Tudor rough landing.jpg (1/1) | Miloch | Aviation Photos | 0 | September 11th 17 03:38 PM |
Martin PBM Mariner pics 2 [09/15] - Martin-PBM-Rough-Landing.jpg (1/1) | Miloch | Aviation Photos | 0 | August 13th 17 03:04 PM |
Kawa..... | [email protected] | Soaring | 34 | August 11th 14 07:43 PM |
Kawa | [email protected] | Soaring | 3 | December 2nd 13 06:26 PM |
PIREP: 2I3 (Rough River State Park, Falls of Rough, KY) | Kyler Laird | General Aviation | 0 | March 1st 04 12:11 AM |