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Cartman2120
11-21-2006, 12:20 AM
I posted this on the MicroJet thread but my coworker thought it was a cool enough video to post for a wider audience. So here is a link to the video of my MicroJet doing 175 MPH passes: http://www.youtube.com/watch?v=46nxgGaGj94

DIALED/CHUCK
11-22-2006, 12:52 AM
Hey Man,

Crash and Tips turned me on to this...

I did some searching and cannot come up with quick answers.

-Motor and Electronics Setup?
-Level or Dive passes?

Nice work! Really Screaming! Kudos!

--C

Cartman2120
11-22-2006, 03:00 AM
Full specs are also in the video.

FlightPower 5s1p 2500mAH battery.
Neu 1110/2.5D 3500Kv motor.
APC 4.75X4.75 carbon prop.
Castel Creations Pheonix-80 ESC.
Medusa 6.0V HV BEC.
HiTec HS-65MG servos.

All the speed runs were done from a ~35 degree dive. Next spring I will do some more runs with it to see what it will do on the level.

-Cartman

DIALED/CHUCK
11-22-2006, 03:44 AM
Cool!

Spanks for the info!

--C

Crash Test Dummy
11-22-2006, 03:56 AM
How about it, that puppy hauls the mail!!! I love the sound of the Neu motor at WOT!! It sounds like it could shread the prop to ribbons, LOL!!

CTD

Jason T
11-23-2006, 03:49 PM
Very nice! Thanks for posting.

max-nix
11-23-2006, 05:28 PM
What does that missle weigh?
How do you launch it?
Does it land "heavy"?

Inquiring minds want to know!
Thanks.

Cartman2120
11-24-2006, 12:38 AM
The all up weight is 27.75 ounces.

It launches using a bungee. The stall speed is around 30-35mph which is beyond hand launching speed. We have launched the plane from both grass and asphalt.

"Does it land "heavy"?" I don't know what that means. It touches down doing around 35mph.

Crash Test Dummy
11-24-2006, 05:12 AM
By landing heavy, I think Man-nix is refering to the landing speed and the sink rate on such a heavy MJ. The wing loading must be alot higher than my 12.6 oz. bird. 35 isn't too bad, I use to have to land my V-Diamond at about 38 MPH [radar timed my landing once] when I 1st got it. I was able to slow the V-D down to about 30 after I got use to her. But after you do a few faster landings you get use to them.

CTD

max-nix
11-27-2006, 02:55 AM
The all up weight is 27.75 ounces.

It launches using a bungee. The stall speed is around 30-35mph which is beyond hand launching speed. We have launched the plane from both grass and asphalt.

"Does it land "heavy"?" I don't know what that means. It touches down doing around 35mph.
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Yes, by landing heavy I mean are the landings gracefull or a manner of controlled crash? Often aircraft with high wing loadings need a very skilled pilot to keep from trashing the model.:eek:

Are you using the Multiplex bungee launcher?

Thanks for the info.

Smasher Bob

Cartman2120
11-28-2006, 01:33 AM
There are currently around 25 landings on the two heavy microjets, 5 of these have been on asphalt. Most all have been good touchdowns and none have caused any damage.

I could not find a source for the Multiplex bungee so I have been using the tubing part of a hi-start. There has not been any problem with the bungee launches. This was not true when trying to hand launch the heavy planes.

Some more info on the plane. I did a static test on the motor using two TP4200 in series and it came out using 70A, which was the same as the 5S flightpower. This bothered me for over a day until I check my Astro power meter's user guide and found out is only reads to 70A. I ordered a new MedUSA 100A meter and remeasured the 5S setup and found out the plane has actually been running at 85A and 15.4V for 1309 watts.

Cartman2120
12-01-2006, 07:55 PM
It was clear today in Boise so we got to put the forth flight on the MicroJet. Today's radar numbers are 180MPH from a 40 degree dive, 169MPH doing a level pass, and 99MPH straight up. That comes out to a climb rate of 8700 feet per minute.

swat1
12-02-2006, 07:04 AM
Is that ok on the 5s1p battery, I thought that would be to much for the battery?

Cartman2120
12-02-2006, 07:59 AM
The FlightPower 2500mAH is rated at 30C continious and 50C burst. That is 75A and 125A. On the ground the static current is 85A and this will drop a little in flight, however since I'm already at mach .85 on the prop it won't unload too much. So I feel this is not to hard on the battery.

swat1
12-02-2006, 08:09 AM
Thanks, I hope you dont mind but I think Im going to copy your setup and put on a stryker

Cartman2120
12-02-2006, 08:17 AM
Be sure and let me know how it works out.

Cartman2120
01-01-2007, 05:48 AM
I did the first test run of uJet-6 today. With a 6x6 CAM Speed Prop and a topped off battery it pulled 94.2 amps at 26.9 volts for 2533 watts. This is over twice the power that uJet-5 was running when it pulled off a 180 MPH pass.

ParkJetsFlyer
01-09-2007, 02:22 AM
Well, that gives a whole new meaning to "Unlimited Vertical" :D Holy Cow!!

scooterpilot
01-14-2007, 06:58 AM
Are you re-enforcing the fues or wings with carbon fiber or anything?

Cartman2120
01-16-2007, 03:46 AM
Are you re-enforcing the fues or wings with carbon fiber or anything?

The longitudinal load is carried on two 10mm x 2mm carbon fiber spars that run from the front of the battery to the back of the motor. These spars are attached to the battery and motor using RTV. The old ESC heatshrink is removed and new heatshrink is placed over the spars, ESC, and motor. This whole assembly is then attached to the fuselage using RTV. The longitudinal spars sit on top of the transverse wing spar, also made of 10mm x 2 mm carbon fiber. The longitudinal airflow from the front air intake passes over the battery and then through the heatshrink around the ESC and motor. The outside of the motor is sealed, therefore all airflow must go through the ESC heatsink and then through the motor core.

Crash Test Dummy
01-16-2007, 04:59 AM
When are you going to fly that puppy/ I hope you get some video of it, that is if your camera man can keep up with it, LOL!!! We'll be watching.

Good Luck.
CTD

VOLUNTEER
01-16-2007, 05:42 PM
What kinda RPMs is that thing turning?

Cartman2120
01-17-2007, 02:56 AM
What kinda RPMs is that thing turning?

The new plane was pulling right at 39000 with the 6x6 prop.

VOLUNTEER
01-17-2007, 04:17 PM
That's smoking! I've got a new geared Neu 1105 in a sailplane and really like it.

jimmi
03-19-2007, 10:54 AM
Love the sound when your winding that baby down:D Thats one fast sob:eek: Jimmi:cool:

Bill G
04-08-2007, 06:36 AM
Its a bird
Its a plane
No, its a Piezo Dot!:D
...and someone wondered why all the dogs were barking.:eek:


Bill

Carjacker
04-08-2007, 11:19 PM
Sounds like a freakin squiky toy.

robertloop
04-12-2007, 05:32 AM
Amazing speed. Must be failrly diffcult to fly. The turbine jets that go that fast are much larger. Orientation tracking has to be a real challenge!

peterkron
04-12-2007, 06:05 AM
The FlightPower 2500mAH is rated at 30C continious and 50C burst. That is 75A and 125A. On the ground the static current is 85A and this will drop a little in flight, however since I'm already at mach .85 on the prop it won't unload too much. So I feel this is not to hard on the battery.

what would happen if the tips of the props broke the sound barrier?

Spencer J
04-12-2007, 06:17 AM
The prop would stall and no longer create thrust...and the plane would be in several places at once in a few seconds :D

peterkron
04-13-2007, 02:33 AM
how does a prop stall?

Spencer J
04-13-2007, 02:37 AM
When a prop spins faster than Mach 1, the airfoil no longer creates lift because there is no atmosphere for the prop to spin in. (Something like that....) Google will give you a better anwser :D

Why are there no Mach prop planes? :)

peterkron
04-13-2007, 02:55 AM
i guess that sounds right. but why does it happen at exactly mach 1? and also how come the giant fans at the front of turbines that bring air into the turbine dont stall?

Spencer J
04-13-2007, 04:40 AM
Turbofans don't go beyond Mach 1. The ones that do really are not turbo fans....but turbofans have a large amount of air pressure behind them in the compression stage.

Cartman2120
04-13-2007, 07:35 PM
what would happen if the tips of the props broke the sound barrier?

The drag really goes up as the tips go through M>1. On a 6S battery I can run the motor to 55,000 RPM with a 4.75x4.75 prop, which is just over mach 1. Most all the extra power required to spin the prop that fast goes up as noise. There are propfans which were designed to run at supersonic tip speeds.

Carjacker
04-14-2007, 04:41 PM
Sound barrier would literally tear that jet apart unless it was made of some pretty strong steel/carbon fiber, then it might have a chance.:D It took years to find a design to hold up against the sound barrier.

Saucerguy2
06-09-2007, 10:17 PM
I bought one of those when they first came out, I used the stock set up, no matter how many times I tried to hand launch it, it refused to fly. It's a very durable plane luckily so I still have it largely in tact, just the gear is stripped out, I might put it back together and go brushless and bungy it as per your reccomendations.

Crash Test Dummy
06-10-2007, 06:38 PM
I bought one of those when they first came out, I used the stock set up, no matter how many times I tried to hand launch it, it refused to fly. It's a very durable plane luckily so I still have it largely in tact, just the gear is stripped out, I might put it back together and go brushless and bungy it as per your reccomendations.

My buddy and I run very lite set ups on our Micro Jets. Heres what we put on ours...............and it is plenty fast, close to the 100 MPH mark!!

Little Screamers Park Jet outrunner
5.5X4.5 to 6X5.5 prop on 3S
3S 1500 Mah packs
HS-55 servos
Micro receiver

It flys very lite and launch is much easer.


CTD

Saucerguy2
06-10-2007, 11:11 PM
So, with the lighter gear, I take it you are able to hand launch it?

Crash Test Dummy
06-11-2007, 05:04 AM
So, with the lighter gear, I take it you are able to hand launch it?

Yup, here is a video of a MJ launch.

http://www.youtube.com/watch?v=3XEdyTgBQyM

It wagged it's wing a bit but not too bad. Make sure you have a little bit of extra up in your elevator just to be safe then trim it out after you get her up in the air. Little Screamers is coming out with a double stator version of this motor and thats what I'm putting on my MJ. I can run a 6X5.5 prop at 24AMPs on 4S!!! Just for the fun of it, here is a video of my MJ doing some low hot passes last summer.

http://www.youtube.com/watch?v=w4Ho1McG1MM

CTD

Saucerguy2
06-12-2007, 11:41 PM
That launch looks a whole lot easier then what I was trying to do with the stock set up, I was throwing out my arm trying to get it up to the proper velocity only for it to do the arc into the ground every time.

I ordered the following motor from UH:
https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=5102

My current lipo's are 3 cell, 11.1, 1000 mah, do you think that's enough juice and power from the motor to get it flying? I plan upon upgrading packs soon, just for now, I've been trying to design everything to handle the same ones and these are cheap so I get a few flights in a row and the original pack of which I payed wayy too much for at the LHS is 1320 mah, yet performs the same as the other's and is the same size/weight.

I also have some smaller cd rom motor's from them, and they are higher performance then the eflight 450's, so wondering if one of those will work as well. I just dread going back to the field with the MJ and having it fail due to lack of power. I'm digging how fast your's is going, it should be alot of fun at those speeds.

Also, I have designed another jet I plan upon putting together after I get the MJ under control, I'd just rather learn from the MJ since it's so durable rather then destroy my eps creation. http://www.wattflyer.com/forums/showthread.php?t=19251 is the thread I've shown it at, you have to scroll past the first few posts to see it, it's a seperate project I wanted to show you guys.

Crash Test Dummy
06-13-2007, 06:06 AM
I don't know if a 1650 KV outrunner is a good choice for the MJ. You want to keep the prop size in the 5 to 6 onch range. They say it should run a 8 inch prop, thats a little big on a pusher jet. Watch your fingers on launch!!!:<

CTD

Saucerguy2
06-13-2007, 08:46 AM
My microjet is stripped down, the servo's are still in service, Multiplex, you guys should market these by themselves, they have proven to be robust and always reliable on many different planes, I guess it's time to re-integrate them back into the original microjet....

UnitedHobbies.com, I'm really a die hard on them, tell me, what's the best starter combo to get the microjet flying well with what they are selling currently? I'll upgrade later if necessary, keep costs in mind in your reccomendations maximizing performance, I as well as most that are rc'ers are on the same and want to outfitt more then just one plane.

I'm digging the performance in the videos,that looks like a whole lot of fun.

Saucerguy2
06-16-2007, 05:38 AM
A great big UUHHGGG, I whipped it back together, used the gear I have on hand and got it flying, that sucker is fast and on it's maiden, it crashed on the roof of the high school. it was banking really hard to the right, so I had full left input into it and managed to get it above the roof, it was going right for the wall of the school, I was bringing it down and it smaked onto the top of a metal housing do da, not sure what it's for, but here I am, looking at this thing up there, can't get to it without a ladder, and it's getting dark so can't stick around school grounds at that point.

Man o man, this is frustrating, I finally got that sucker flying and now I'm looking at a dead lipo, rx, mixer, etc. since it's supposed to rain tonight. The motor flew off, at least the bell, around 50 feet so that part is toast. I just hope the battery unplugged itself since it was just sticking out of the fuse and it did so on anther crash before. I'll never fly experiementals, or new planes at that place again, between having to avoid the school to the batters cage, I'm done with that place.

Anyway, going to try the fishing pole system tomorrow, hopefully the rain isn't going to destroy everything, it just sucks to get a taste for what this one can do and not be able to fly it.

Here are the specs:

11.1 1000mah lipo, gws receiver, TowPro Brushless Outrunner 2408-21 (https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=665) and 8X4 slowfly prop. No need to go in debt over this one, I didn't know if it would work, obviously it does and quite well.

Bill G
06-16-2007, 07:31 AM
Yes, its very frustrating, especially when the crashes are needless, like my cold solder joint breaking, causing a motor overload, in turn shutting down the BEC. Got rebuilt that day, but those rebuilds are frustrating, and not enjoyable. To top it all off, you end up blowing a bunch of hours to make it even better, so that you can think that there was some gain from the experience.

Before, during:eek:, and after:

Bill

Saucerguy2
06-17-2007, 01:06 AM
I'd like to know when a crash is actually needed, hehe.

Good news, I dragged the ladder to the local, it was too short so I stacked it on top of a table that happened to be nearby and was able to retrieve the plane, luckily it didn't rain so hopefully the gear outside of the motor are ok. The plane is still quite fixable so she'll fly another day.

I did a search on the web to find another replacement arf body for it, since it's discontinued, nobody is carrying them so it looks like I'll be making a few extra's in house. Even though the maiden was short I got a good enough taste to know this is exactly what I've been striving for performance wise. This one will stay flying at my normal field from now on, it's just too fast for the smaller ones.

turbine50
07-10-2007, 02:44 AM
Why mach 1? Because that's where a shock wave begins to form starting at the prop's tips (they are going the fastest around). A shock wave creates mucho drag in turn killing the propeller's efficiency. Look at the video of the yellow and black plane on this: www.tanicpacks.com (http://www.tanicpacks.com)