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Jan 24, 2018, 07:48 AM
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Zenoaheli's Avatar
waow good job Par, so what airframe do you think would be a good match for such a beastly power plant?
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Jan 24, 2018, 09:02 AM
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I think any jet that is designed to operate between 25-32lbs AUW will make a great candidate. The power system/ESC/batteries will weigh in at around 10-15lbs based on battery selection and whether one chooses to go 18s, 20s, or 22s. I would def go 22s on anything designed to flying at around 30lbs worth of weight.

Of course, for those who are very careful with the weight during the build phase, it’s theoretically possible to build a less than 25lb AUW jet with a greater than 1:1 t/w ratio. For this, I would go with 18s, 6000mah, and the 25-27lb fan. Flight time will be a little short but it’ll scoot like nothing else in it’s class.
Last edited by Par_18; Jan 24, 2018 at 09:46 AM.
Jan 24, 2018, 10:08 AM
3d and EDF, some scale
MustangAce17's Avatar

Oh yes :)


I can just imagine a nice Eurofighter with the 22s fan, now I gotta look it up to see what AUW is

Looked it up, 24-26 lbs auw, definitely doable!
Last edited by MustangAce17; Jan 24, 2018 at 10:20 AM. Reason: Added pic
Jan 24, 2018, 10:24 AM
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Quote:
Originally Posted by MustangAce17
I can just imagine a nice Eurofighter with the 22s fan, now I gotta look it up to see what AUW is

Looked it up, 24-26 lbs auw, definitely doable!
Oh man that would be sweet. Ive always wanted that jet and this may be the reason to do it. Id def go 18s/8000 mah with the 25lb fan.
Jan 24, 2018, 10:27 AM
3d and EDF, some scale
MustangAce17's Avatar
There is a turbine one a friend has at the local field I've been meaning to rejoin, I'll try to get some pics soon, price isn't bad for that much jet! The 18s would do what around 4 minutes?
Jan 24, 2018, 10:29 AM
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Here’s some more interesting food for thought. When I started this, I was only pushing 5 to 6kw at most and that used to sound scary being right next to it when it was running. With the 30lb fan, 6kw is the best “cooling” point for the motor producing 15lbs of thrust at 65amps and most likely a good cruise setting for your average 20-25lb jet. The fan is damn near “quiet” when I go from 38k to 26k as seen in the video. My neighbors must hate me.
Jan 24, 2018, 10:32 AM
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Quote:
Originally Posted by MustangAce17
There is a turbine one a friend has at the local field I've been meaning to rejoin, I'll try to get some pics soon, price isn't bad for that much jet! The 18s would do what around 4 minutes?
Yea with 8000mah, 4 mins is a good expectation. 10ah would be even better...6x6s5000mah batteries. Pretty economical setup.
Jan 24, 2018, 10:36 AM
3d and EDF, some scale
MustangAce17's Avatar
Well if I do end up with one of those Euros and your fan, I will definitely show it off at several fly ins, it is just a matter of time before I will have one
Jan 24, 2018, 11:08 AM
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Quote:
Originally Posted by MustangAce17
Well if I do end up with one of those Euros and your fan, I will definitely show it off at several fly ins, it is just a matter of time before I will have one
Awesome! If you end up getting one, it looks like 20s would be the way to go using 6000mah/65c turnigy graphenes. This will give you a power system weight of 13-14lbs. 6000/45c graphenes will result in a power system weight on only 12-13lbs. 45c is more than sufficient on 20s with 27lbs of peak thrust.
Last edited by Par_18; Jan 24, 2018 at 11:29 AM.
Jan 24, 2018, 11:44 AM
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erh7771's Avatar
Hey Par

2 things

1. How much for tail cones by themselves?

2. What connectors are you using for the packs?

Thx in advance for any input

regards
Jan 24, 2018, 11:50 AM
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erh7771's Avatar
Quote:
Originally Posted by Zenoaheli
waow good job Par, so what airframe do you think would be a good match for such a beastly power plant?
80% of all single turbine sized frames can fly on 30 lbs pretty good

Remember efflux becomes just as important or even more important after static thrust gets the model moving IMHO.

If the installed efllux is around 250 ish there's some REALLY decent speed to be had in a lot of scale models, sport models even more.

Here's a 1/5 scale F-16 flying on around 30 lbs (after turbine pipe head loss), big jet, the AUW is near 50 lbs with fuel

Scalejets F16 with Pegasus HP 16kg/35.3Lbs (7 min 33 sec)


Skymaster is now making a super light series with less than 20 lbs with gear painted and servos installed for the 7 - 8 long foot ish jets ... good times
Last edited by erh7771; Jan 24, 2018 at 11:59 AM.
Jan 24, 2018, 12:39 PM
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Quote:
Originally Posted by erh7771
Hey Par

2 things

1. How much for tail cones by themselves?

2. What connectors are you using for the packs?

Thx in advance for any input

regards
Tailcones for 56xx/58xx motors alone are $55 plus shipping ordered directly though shapeways.com.

I use 5.5mm gold connectors from hobby king.
Jan 24, 2018, 07:32 PM
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Thread OP

22s Test run #2...new record


Did another test today with warm batteries and set a new record...31.67lbs/~39000k. This test is much more representative of what I expect to see from a good strong set of batteries. I also ran the motor at full power for a long time to really punish it. Ill post the video later. Fan is performing absolutely stellar. There is no indication of blade/shroud rub, which means the rotor is rock solid at this high RPM.
Jan 24, 2018, 09:08 PM
Lee Liddle
Knife Liddle's Avatar
This is awesome Par. 22s full voltage 39k rpm. That kv is working out perfect for maximum performance in the Dynamax. Well over 31lbs at peak power is something that I've dreamed about for probably 10 years, and now it's really available. It's not vapor-ware, it's not some hypothetical extrapolation of what the fan should be capable of, it's real, and I'm going to have one in my hot little hands .....
I can't wait!!

Get in line boys...........it starts right behind me!


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