View Single Post
Old Nov 01, 2006, 07:20 AM
Red 61 is offline
Find More Posts by Red 61
Outcast outlaw
As far away from RCGroups and the AMA as possible!
Joined Aug 2004
6,601 Posts
Quote:
Originally Posted by crxmanpat
So you're looking to pull only 13.5 amps total (static), not per side?
Yes -- 13.5 amps total (static) -- not per side.

Quote:
Originally Posted by crxmanpat
My 22 is total, so I'm only pulling 11 per side, and probably less than that in the air.
Right -- this is how my other P-38's have always turned out. I'm going to try something different this time.

Quote:
Originally Posted by crxmanpat
Is there a setup available that would do 13.5 amps total on both motors, and still fly a 2lb plane?
Well, as I said above, I'm going to try something different this time... I will let you know if it works after the maiden! (Then again, I have to start the build first!)

Here's my reasoning -- with a twin motor setup, your airplane will have twice the thrust, but will not fly any faster. I'm going to try to cut down the thrust, increase the top speed, and cut the amp draw in the process.

My first P-38 weighed 40 ounces, and had 59 ounces of static thrust...

If we assume my GWS-38 comes in around 35 to 40 ounces, I am reasonably certain it will fly on 44 ounces of total static thrust (17.2 ounces of total in-flight thrust). Warbirds like speed more than thrust anyway -- 47 mph on 3s, or 59.9 mph on 4s sounds REALLY good to me.

The big test will be tomorrow morning -- when I try the power system (well, one side of the GWS-38 power system) on my GWS ME-109. My ME-109 currently flys great with a 9x7.5E APC prop -- the only change I am making is that I am switching to an 8x8E APC prop.

If, for some strange reason, the P-38 airframe does not fly well on the 8x8 props, I can always switch back to the 9x7.5 props -- I KNOW it will fly with that! On the 9x7.5 props, at WOT, for BOTH motors: 18.22 total amps drawn, 55 ounces of total static thrust, 25.6 ounces of total in-flight thrust, 42.67 mph top speed. This amp draw is still pretty high, but it's less than the 24.8 amps my Flying Styro P-38 is drawing!!!

(I apologize for the long post!)
Red 61 is offline Find More Posts by Red 61
Reply With Quote