wjbender

Hi all,

I'm building a Hangar 9 Pulse XT 40 with the electric option. I am looking to build a sport plane (not 3D) that will give strong aerobatic performance, yet disassemble easily for travel on commercial airliners. (vacation plane)


The advertised weight is 5 Lbs without battery, and The recommended motor is an E-Flight Power 46 motor with the following: specs:


925 Watts, 670 KV, weight 290 grams (10 oz) The suggested battery is 4200mAh 2S2P 7.4V Li-Po

If I want to use A123 cells, what configurations would give me equivalent or better performance?

I was thinking of using a 2S2P 4600Mah A123 pack. That pack would give me 5.9 V under load Vs 6.6 V for a loaded LiPo
Since the LiPo is approx 11.1% higher voltage under load, 11.1 x 670KV gives ~ 752 KV to get the same RPM

Should I consider using a motor with a higher KV to compensate for the lower battery voltage of LeFe cells or just change to a different prop?

How about a Scorpion SII-3026-890 KV (V2) with the following specs:

KV 980, 1025 watts, weight 205 grams


Would this work well? Does anyone have alternate motor suggestions using A123 batteries?


Thanks in advance for any comments or suggestions

patnchris

I hope you read those spec. properly......That plane, with that motor requires 2 of those lipos.....I have this plane and fly it on a single 5S 4000 ma 15C pack....I'm using the Exceed MonsterPower 46 which has the same specs as the E-Flight Power 46......I realize you can pull some monster amps from those A123's but keep in mind that you will need at least 18-19 volts to pull the power you want. By the way....I don't know where you found the spec. on the E-Flight Power 46 but it is rated at 800 watts continous.....If you pull a constant 900 watts from it, it will burn up.....Ask me how I know....LOL....As far as the Scorpion motor goes, be very careful when reading their ratings.....They are not all that they say they are....Ask me how I know that.....

There are motors out there that will produce the watts you want with a higher KV....However the trade off would be more amps.....Truthfully....I've got mine propped for 850 watts at WOT, but seldom use it. The Pulse XT has a very slippery air frame and is quite fast. While I don't have unlimited vertical, I find I don't need it, because at the speed it flys, it doesn't need to go vertical very long before it's too high....Pat

bobferguson

I run 4s2p 4600 A123 packs in my Pulse. It flys good at this power. But I also fly 5s 6000mah pack with smaller prop and it is a rocket compared to the A123 packs. But I mostly run the A123 packs as they more enough power for me. I am using a Power 46 motor.

thrawn150

I can not speak for the A123, but with the 5S lipos and a power 46 its fast. I have had this plane for 2 years.

wjbender

I don't see any mention of cutting cooling openings in the undersife of the fuze to let cooling air out. What are you guys doing about cooling the esc and batterirs