Tag: Ryan

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Funny, Those In Power Often Rewrite The History Books

I’ve watched and listened to the DNC (Democratic National Convention) over the last 3 days. Nearly every speaker talked about the million jobs saved when Obama and Biden bailed out the auto industry.

The auto industry bailout was announced December 19, 2008 by the treasury department.
Bailout Timeline

Wiki page on Bailouts describing the request by the auto industry in 2008 and the agreement of president Bush in early December. Wiki Bailout Page

New York Times runs a story on December 19, 2008 entitled:Bush Approves $17 Billion Auto Bailout

And finally:

Barack Obama was sworn into office as our 44th president on January 20th, 2009.
Wiki Inauguration of Barack Obama

Is this a lie?  DNC 2012 video below:

Maybe I have this wrong. However, it appears there was a full month between the announcement of the Auto Bailout (Dec 19, 2008) and Inauguration Day (Jan 20, 2009).

Was Obama and Biden actually running the country in the months prior to Inauguration day?

Is the claim a fabrication intended to fool those who would never bother to look back at historic records?

When an entire campaign arranges the calendar in a different order and nobody notices, does it say something about our average citizen?

Does it say something about our media that calls itself “news”.

What does it say when those that make the claim have no fear they will ever be discovered?

Did you hear about this obvious error (or fabrication?) on your local news channel? Maybe you should consider very carefully what you define as news.

Other interesting items:
Fact Check.org on bailout claims. Did you know that the auto companies did actually under Obama file bankruptcy which is what they claim Romney and Ryan would have preferred to the detriment of the country. Weird isn’t it?

Regardless of who you plan to vote for or how you feel about the auto industry bailouts, you should always take time to do a little basic research. A little reading and a little study goes a long way to assuage ignorance. I’m not trying to tell you what to think. I’m trying to urge you to think.

My name is Dave Thacker and I’m doing something about it.

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Converting A Model From Lipo to A123 (LIFE) Cells

Chris from Michigan Asks;

Hello Dave,
I would like to power my Ryan with A123 cells. I have been using a 9s 4p 6000mah Lipo pack to power a Hacker C50 motor.
If I understand things correctly, I believe that I need 4packs 6s 2300mah to equal the same watts and flight duration as the Thunder Power packs that I have been running.
Because of the cost of these A123’s, I want to be sure that what I am ordering is correct!

Chris,

To match duration of a 6000mah Lipo, you’ll need at least 6000mah in A123 which will be 3P. You’ll actually be a little over as the 2300mah A123 cells actually test most of the time around 2200, at 3P you’ll have 6600mah which should result in slightly more flying time.

I assume your 6000mah lipo is made up of 1500mah Parallel packs. So, 4 1500’s in parallel = 6000mah.

If what you really meant was your running 6000mah cells, 4 in parallel, then your pack size is 24000mah which would be about 11P or 11 A123 in parallel. I am not thinking you meant you had a 24000mah pack.

If your running 6000mah total in the airplane, and are thinking of running A123 in 2P for about 4400mah real world, this may be just fine. I generally only use the top 60% of a Lipo (70% max) on a routine basis. 60% of 6000 3600mah, 70% is 4200mah. I’m more comfortable running A123 cells a little deeper than Lipo’s as the risk of hitting BEC cut off cause me less worry. (Hitting BEC cut off is hard on Lipo’s) So, running a 4400 A123 down 80% is 3200mah. So, a 2P A123 should get close to the Lipo in actual use. However, your not running as much cushion between a solid end of flight habit and the bottom of the battery.

For matching running voltage, you’ll need 10 to 11S A123. I’d probably go to 11. At 12S, you’ll definitely have 3-4 more running volts. It will be like 9.8 Lipo or something like that.

To do conversion at nominal voltage, (# Lipos * 3.7) / 3.3 nominal of A123 = cell count.
To do conversion at full voltage: (# Lipos * 4.2) / 3.6 full voltage of A123 = cell count.

Nominal conversion is: 9 Lipo = 10.09 A123 cells

Full voltage Conversion is: 9 Lipo = 10.5 A123 cells.

Since you do most of your flying between full and nominal voltage I lean towards the full number for this estimation. 11 is the best choice. 10 you might notice a slight decrease in performance by your motors KV * volt reduction of the 10S pack. Right in the front of the pack, the 9S Lipo is 37.8v. Right in the front of a 10S A123 your full voltage will be 36v. So, KV X 1.8 = drop in top rpm. If your running a 500kv motor, that’s 900 rpm.

If you go with 11 cells, you’ll be starting out at 40.4v meaning your over the Lipo voltage by about 2.6v. So, you pick up (with 500kv motor) 1300 prop rpm.

Either choice means to get back to exact performance you had on Lipo you may need to alter the prop slightly, maybe an inch more pitch for the 10S A123 and an Inch less pitch for the 11S A123 or something similar to re balance things back out.

So, on balance, not knowing everything about the model and power system, I’d lean towards 11S. If you go 12S as your proposing, you’ll likely end up way over on RPM and Watts from where you were with the 9S Lipo pack. Important considerations here are if you mind a little more or a little less power (if the ESC minds more amps/voltage) and if you would need to change props, is there a convenient prop up or down that would suit the model and flying preferences. For example, if your running right at the edge of the ESC at this time and didn’t want to upgrade it, a slight decrease in power is acceptable, 10S becomes the obvious choice.

Another consideration not taken into account above is there can be a wide variation in quality of Lipo’s people are using out there. (not picking on Thunder Power, remarks for general readers of this post) Your current pack which may be performing just fine for the application may be worn and not really up to snuff compared to the original new condition. Thus if the current lipo has more voltage depression than it should, an A123 10S pack depressing less by some significant amount, could end up taching and watt metering out higher than the battery you are now using.

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