Comparison of Estimate E6/E7 Weights

[ben_beyer]

So, one of the things I'm interested in is how disc loading and optimum set up can be achieved.  Fellow pilots may have different desires but mine are specifically related to disc loading as an estimation of flight performance assuming lighter flies better and I also would like to be able to fly for at least 5 minutes and prefer 6 minutes or better. 

What I've done is found a weight of an E7 with no batteries and it was 7.9 lbs (3586.6 grams).  I then looked at the weights and maH capacity of various battery packs.  I used Gens Ace because they are pretty popular at the current moment and I didn't want a huge table to start out with though I could easily expand my calculations.  What I have for calculations are maH, # of cells, total maH (# of cells X maH; I feel it is important to consider total mah because if you're making comparisons and looking at 5S or 6S 3850's for example, then there are different total maH available), total weight of packs since 2 are often used in 10S and 12S set ups, mah/g, estimated machine weight, disc area using 600mm blades for E6 and 690mm blades for E7, and disc loading as milligrams/millimeter^2 (estimated machine weight divided by disc area).  I also included a couple Sky LiPo packs for comparison.  I realize most pilots won't be setting up an E7 with a 10S set up, but I just wanted to share some information I have put together.  The 282600 disc area is an E6 and the 373738.5 disc area is an E7.

Battery   # of   Weight   Total   Total Weight   Battery   Estimated Machine     Machine     Disc   Disc Loading
maH          Cells      (g)        maH       (g)               maH/g          Weight (g)               mah/g        Area         mg/mm^2
3800         5           525    38000     1050             36.190       4636.600                    8.196       282600        16.407
3300         6           533    39600     1066             37.148       4652.600                    8.511       282600        16.464
5500         5           746    55000     1492             36.863       5078.600                   10.830     373738.5     13.589
4000         6           658    48000     1316             36.474       4902.600                    9.791      373738.5     13.118
5300         5           630    53000     1260             42.063       4846.600                    9.694      373738.5     12.968
Sky LiPo for Comparison
4400         6           691    52800     1382             38.205       4968.600                   10.627     373738.5     13.294
5000         5           638    50000     1276             39.185       4862.600                   10.283     373738.5     13.011
5000         6           764    60000     1528             39.267       5114.600                   11.731     373738.5     13.685

[Gregor]

Good info, thanks for sharing.  Here's my feedback, hopefully recieved as constructive.

The inclusion of 10s is confusing. If your are going to include 10s I'd break it out in a seperate table and also add 12s pack configurations above 4000. Also when comparing 10s to 12s, it can be much more helpful to compare the usable relative watt hours between the packs.  This is better indicator of expected run time. 

To calculate take 80% of the pack's Ah and multiple times the pack's nominal voltage (3.7v per cell loaded).

For instance:

12s 4400mah  (4.4x0.8)x44.4 = 156.3 wHr.
Working the formula backwards gives is a 10s pack size of 5280mah for comparable wHr

[ben_beyer]

Good feedback, thanks!  I'll work on doing some additional number crunching and revise the table.  The one problem here is that I do not have a difference in weight between 690 blades and 600 blades.  That could affect the numbers some, but I don't know how much. 

[ben_beyer]

                                   # of       Watt        Estimated             Watt             Disc
Machine    maH    Cells       Hour    Machine Weight     Hour/Kg      Loading
E6            3800     10         112.48          4922.6                  22.850        17.419
E7            5500     10          162.8           5451.6                  29.863        14.587
E7            5300     10         156.88          5161.6                  30.394        13.811
E7            5000     10            148            4862.6                  30.436        13.011
E6            3300     12         117.22          4917.6                  23.836        17.401
E7            4000     12         142.08          5231.6                  27.158        13.998
E7            4400     12         156.29          4968.6                  31.455        13.294
E7            5000     12          177.6           5114.6                  34.724        13.685