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Boeing 727 question

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Old 05-11-2016, 03:55 PM
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Sky_high
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Default Boeing 727 question

Hello all,
I'm going to build a 727 soon by Hotwire cutting insulation foam. I have a few questions regarding my build:
1. I initially planned to mount 2 40-50mm edf on the 2 outer engines, but I discovered that I could fit a 70mm fan into the fuselage. The 3 engine fittings could serve as intakes for it and the exhaust would be where the top engines s duct thrust would be. Which one do you guys think is better? I'm open to any other suggestions.
2. How do I make this plane fly slow and scale? I'm flying at my local park which is roughly the size of a football field.
3. Can someone explain the basics of building Hotwire cut plans? Do I just cut each section then glue them all together?
4. Should I use carbon fiber or bamboo sticks to reinforce the plane?
(If carbon fiber please direct me to a source that sells it)
Any help appreciated!
Thanks

EDIT: Just realized that there is also a electric plane section, did I post in the wrong forum? If so sorry bout that and would appreciate if a mod moved me to the proper section.

Last edited by Sky_high; 05-11-2016 at 04:06 PM.
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Old 05-12-2016, 10:36 AM
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I seems to me that a single large fan that far aft would make it tail heavy.
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Old 05-12-2016, 01:16 PM
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Originally Posted by rgburrill View Post
I seems to me that a single large fan that far aft would make it tail heavy.
Not necessarily. There are four things you need to remember:
1) The 727 had the highest degree of sweep of any commercial transport aircraft built to date
2) The wing roots are actually aft of the middle of the fuselage. This is very evident on the 200 series planes.
3) The easy way to identify the two versions are the 100 has a shorter fuse and a round center intake while the 200 has an oval center intake
4) The fuse isn't a round tube, it's actually two different diameter tubes stacked with the larger tube on top
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Old 05-12-2016, 05:20 PM
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Originally Posted by Hydro Junkie View Post
Not necessarily. There are four things you need to remember:
1) The 727 had the highest degree of sweep of any commercial transport aircraft built to date
2) The wing roots are actually aft of the middle of the fuselage. This is very evident on the 200 series planes.
3) The easy way to identify the two versions are the 100 has a shorter fuse and a round center intake while the 200 has an oval center intake
4) The fuse isn't a round tube, it's actually two different diameter tubes stacked with the larger tube on top
Thank you for replying for me! Anyways I have a few questions about the edf units. These are my options:
-70mm edf: http://www.hobbyking.com/mobile/view...dproduct=49488
-64mm edf: http://www.hobbyking.com/mobile/view...dproduct=21148
-2 50mm edf: http://www.hobbyking.com/mobile/view...dproduct=31823
Which one of these do you guys think is best. The only probables I have is for the 70mm, the exhaust will have to be bigger than scale, because of the thrust tube which would have to be about 60mm, while on the 64 it would be about 53mm. I'm open to any other suggestions.
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Old 05-13-2016, 01:21 AM
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Hi

A Boeing 727? Scratch build by your own?
I would prefer the easier way.

What about this one? For 60 $? For two 50mm EDF?


Here's the link: http://store.laser-design-services.c...roducts_id=217

And here the Plans:
http://www.laser-design-services.com/Boeing%20727%20plan.bmp


And a build thread:

http://www.rcgroups.com/forums/showt...&highlight=727

Ok

regards. Andi
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