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        SU-27 Flanker update

#1 Daren Oct 02, 2001 12:58 AM

SU-27 Flanker update
 
Here's the latest status update on Dan and my Flankers. The fan units (Wemo Mini 480s w/Speed 480 Race BB) are installable and the inlet and exhaust ducting has been completed. The other systems (retracts and elevons) were installed before the final sheeting went on and are complete. The rear hatch (where the speed board normally is) allows access to the battery pack (16 - 1100mah AU) and the front hatch allows access to everything else. Now it's on to sanding and finishing.<P>
<img src="http://www.allaboutguppys.com/flanker/flanker01a.jpg" width="800" height="606"><P>
<img src="http://www.allaboutguppys.com/flanker/flanker05a.jpg" width="800" height="294"><P>
<img src="http://www.allaboutguppys.com/flanker/flanker07a.jpg" width="800" height="566">

#2 Oct 02, 2001 01:24 AM

daren: the pic's didnt show up...............gregg

#3 Daren Oct 02, 2001 01:32 AM

Better?
 
Quote:

Originally posted by p471701
daren: the pic's didnt show up...............gregg
Arggh! How about now?

Daren

#4 Oct 02, 2001 01:38 AM

that's one good looking sukoi! the framing is so impressive it's a shame to cover it up.............gregg

#5 avie Oct 02, 2001 03:48 AM

congrat on one piece of work !!:cool:
one thing, what is the metal in the nose ?

once again,congratulations !!

Avi

#6 Kevin Cox Oct 02, 2001 09:05 AM

Great looking ship guys!

#7 dorysch1 Oct 02, 2001 09:20 AM

the thing in the nose looks like a big Capacitor? But Great looking Jet wow!

#8 Plane Crazy Oct 02, 2001 09:33 AM

Nope, looks to me like a retract air cylinder in the nose. This thing have retracts??

Can't wait to hear about first flights.

Gordon

#9 Daren Oct 02, 2001 10:07 AM

Air cylinder
 
Gordon gets the kewpie prize. The air cylinder will be housed in the hollowed-out nose cone (not yet attached).

Gregg:
Thanks for the kind words. Dan's is just as pretty.

Gordon:
Both do have retracts. We are using the Spring-aire 600 series.

To all:
Estimated AUW will be between 4.75-5.25 lbs. Once they're finished, we have a pretty stringent test program planned before the first flights; thrust and tailpipe velocity, then low and high speed taxi tests. Fortunately, we have a rather large paved flying field on which to perform these tests. We'll be posting more pics as the airframes progress.

Daren

#10 avie Oct 02, 2001 11:03 AM

Hi
another question. do the fans deliver enough thrust and power ? it seems quite heavy for the thrust they would provide (400 grams each by wemotec ?)

Avi

#11 dorysch1 Oct 02, 2001 11:22 AM

you may want to run brushless motors to get adequate thrust on a small fan no? but I am new at this and relatively lazy to do the math I am getting burned out trying to get mine finished before it snows

#12 Herb Oct 02, 2001 11:58 AM

Quote:

Originally posted by avie
Hi
another question. do the fans deliver enough thrust and power ? it seems quite heavy for the thrust they would provide (400 grams each by wemotec ?)

Avi

Each MF480 will deliver about 14 oz of static thrust on 8 cells. With a weight of about 5pds and an est 10% in ducting losses, static thrust to weight is around 0.31, and Watts per pound around 55.

#13 Haldor Oct 02, 2001 11:59 AM

Sweet!

I hope the powerplants will do - power seem low as each fan wont provide more than ~140W in/84W out.

#14 Daren Oct 02, 2001 12:23 PM

Hope so...
 
Quote:

Originally posted by avie
Hi
another question. do the fans deliver enough thrust and power ? it seems quite heavy for the thrust they would provide (400 grams each by wemotec ?)
Avi

The WB-57 weighs about the same and flies pretty well on this set up. Granted it has more (lots!) wing area, but also a higher amount of parasite drag. The Flankers' estimated wing loading is approximately 24 oz./sq. ft.

Our own concerns as to whether the power will be enough is why we have the testing planned that we do. If the static thrust and tailpipe velocity look okay, we'll move onto taxi tests. Fortunately, our runway is about 900 ft. of 150 ft. wide asphalt, so there's plenty of room to get slowed down (or land) in case it doesn't look like they'll fly. This is one of the advantages of ROG, you have a much wider go/no go window in which to decide.

Daren

#15 JasonJ Oct 02, 2001 03:29 PM

ssssssswwwWWWWWWEEEEEEEEEEEeeeeEEEEEEEEETTTTTTTTTT TT!!!!!

Ahhhh I just LOVE that thing! Eeeahhhhh Its so cool I just cant take it! (Jason goes into crazed fit, contemplates quiting job and locking himself in a tool shed with a 2 year supply of balsa, tools, supplies and some food :) )

Ok, Im ok now, that thing is great guys! I love the SU 27, go figure :) . I also happen to have 2 minifan 480s and 2 race speed 480 bbs, so I am very optimistic (spelled hopefull) about your low cost power config :) .
Just imagine such a cool scale twin EDF with ROG retracts that could fly with less than $200 worth of power plant,,,,,,,, :) .


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