AMA Discussions Discuss AMA policies, decisions & any other AMA related topics here.

Model Aviation page 4off

Reply

Old 12-29-2018, 03:17 PM
  #1  
tailskid
Thread Starter
My Feedback: (34)
 
tailskid's Avatar
 
Join Date: Nov 2001
Location: Tolleson, AZ
Posts: 9,419
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Question Model Aviation page 4off

Article on page 40 and following.....


Very interesting article but I don't know what "wing inertia" is.....anyone care to explain that term means?

Thanks,

Jerry

Last edited by tailskid; 12-29-2018 at 03:23 PM.
tailskid is offline  
Reply With Quote
Old 12-29-2018, 04:54 PM
  #2  
franklin_m
 
franklin_m's Avatar
 
Join Date: Nov 2005
Location: State College, PA
Posts: 2,964
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by tailskid View Post
Article on page 40 and following.....

Very interesting article but I don't know what "wing inertia" is.....anyone care to explain that term means?

Thanks,

Jerry
I've flown military tactical for 22 years, graduated from the US Naval Test Pilot School, did developmental flight test for two years, taught at USNTPS, and graduated from US Naval Aviation Safety School ... where we did structural analysis work (as part of mishap investigation), and I've NEVER heard that term before. But whatever, I guess they were filling space.

And why do I suspect that? Because the same article is horribly edited. For example, the last two paragraphs at the bottom of page 42 and the first two at the top of the left column on page 43 are repeated word for word on page 43 in the second column ( about the middle of page ).

Keep this in mind as you consider how many people are being paid with our membership dollars ... to create and edit this magazine.

ADDED: I keep finding more errors the closer I look. The diagrams referenced don't match the text that references. Furthermore, some of the diagrams are just plain wrong. For example, the text referencing figure 1.3 discusses a "constant lift distribution" but, but the diagram shows NOT a constant lift distribution. Another is the text that references figure 1.4, a tapered wing. Yes, it shows that the lift distribution changes across the span, but it shows a constant weight distribution ... which is not true for a tapered wing (unless the builder deliberately uses more dense components the further out on the wing they go ... nonsensical).

Last edited by franklin_m; 12-30-2018 at 07:59 AM. Reason: Added info
franklin_m is offline  
Reply With Quote
Old 12-30-2018, 08:26 AM
  #3  
tailskid
Thread Starter
My Feedback: (34)
 
tailskid's Avatar
 
Join Date: Nov 2001
Location: Tolleson, AZ
Posts: 9,419
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I noticed the "cut and paste paste" also.
tailskid is offline  
Reply With Quote
Old 12-30-2018, 09:09 AM
  #4  
dionysusbacchus
My Feedback: (25)
 
dionysusbacchus's Avatar
 
Join Date: Dec 2002
Location: McQueeney, TX
Posts: 2,479
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by tailskid View Post
Article on page 40 and following.....


Very interesting article but I don't know what "wing inertia" is.....anyone care to explain that term means?

Thanks,

Jerry
I'm not going to offer an appeal to authority, don't listen to me, look it up.

I didn't read the article so I don't know the context. Inertia is simply how we talk about matter and movement. For example in a spin the heavier the wingtips the more force it will take to stop the spin (wingtip inertia), so the lighter the wingtips the faster you can recover from a spin for example. Lets look at the Corsair, it has fabric outer wing panels and plywood ailerons, the lighter the wingtips the more responsive the airplane will be. The heavier an object is and the faster it moves the more force is needed to slow it down or change it's direction. Bowling ball inertia, airplane inertia, wingtip inertia, you get it.
dionysusbacchus is offline  
Reply With Quote
Old 12-30-2018, 09:38 AM
  #5  
Stickslammer
 
Stickslammer's Avatar
 
Join Date: Aug 2017
Location: Tennessee
Posts: 297
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

  1. the property of matter by which it retains its state of rest or its velocity along a straight line so long as it is not acted upon by an external force.
I would guess from the basic physical definition of inertia that they were referring to the constant straight line operation of the wing. Which may not have anything to do what the article is about. Ha,ha. I wish I could read it now, but the Jan. issue has still not arrived.
Stickslammer is offline  
Reply With Quote
Old 12-30-2018, 09:41 AM
  #6  
Appowner
 
Join Date: Nov 2017
Posts: 841
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Well I did look it up. More out of curiosity than anything else (just so my motive isn't questioned by the forum motive cop). And it appears wing inertia is a term first used in reference to living creatures with wings. Birds, bugs, bats etc. Used by Biologists of various types in their study of flying creatures. I can actually see where this term could have been in use in this capacity prior to 1903. And as terms go, it has managed to migrate to the aviation world. But how widespread is it's use? And is it used in any official capacity? i.e. is it a commonly and recognized term in the full size aviation community? Design and engineering documents comes to mind here. I do not know. Nor do I care. It's a curiosity and nothing else. Which is I believe why the OP posed the question in the first place.

And for those more curious than I, a simple demonstration can be accomplished by taking a model of yours, adding several ounces of lead to each wing tip and seeing how that impacts roll and banking. For more fun, add all the weight to just one wing tip. Preferably the left one.

Last edited by Appowner; 12-30-2018 at 09:45 AM.
Appowner is offline  
Reply With Quote
Old 12-30-2018, 10:17 AM
  #7  
Stickslammer
 
Stickslammer's Avatar
 
Join Date: Aug 2017
Location: Tennessee
Posts: 297
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Well, now, the forum motive cops may infer from this that you are trying to get someone to crash their airplane in a most dangerous way!
Stickslammer is offline  
Reply With Quote
Old 12-30-2018, 01:31 PM
  #8  
Appowner
 
Join Date: Nov 2017
Posts: 841
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by Stickslammer View Post
Well, now, the forum motive cops may infer from this that you are trying to get someone to crash their airplane in a most dangerous way!
Well if someone is stupid enough to try that, they probably shouldn't be in any activity involving moving parts/objects!
Then again, experience is an excellent teacher. And a fool will have no other.
Appowner is offline  
Reply With Quote
Old 12-31-2018, 12:48 AM
  #9  
Hydro Junkie
 
Join Date: Nov 2004
Location: Marysville, WA
Posts: 7,481
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by tailskid View Post
Article on page 40 and following.....


Very interesting article but I don't know what "wing inertia" is.....anyone care to explain that term means?

Thanks,

Jerry
It sounds to me like a term someone came up with the try to explain something they had limited to no knowledge about. Stickslammer gave the definition of inertia and, when you throw in "wing", it sounds to me like someone is trying to describe, somewhat incorrectly, how a wing can keep a plane in a spin or stop it. Unfortunately, it doesn't take an aerodynamics expert to understand that the lift and drag of a wing are just as, if not more so, important as the inertial effect of the wing structure.
Hydro Junkie is offline  
Reply With Quote
Old 12-31-2018, 07:29 AM
  #10  
franklin_m
 
franklin_m's Avatar
 
Join Date: Nov 2005
Location: State College, PA
Posts: 2,964
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Originally Posted by Hydro Junkie View Post
It sounds to me like a term someone came up with the try to explain something they had limited to no knowledge about. Stickslammer gave the definition of inertia and, when you throw in "wing", it sounds to me like someone is trying to describe, somewhat incorrectly, how a wing can keep a plane in a spin or stop it. Unfortunately, it doesn't take an aerodynamics expert to understand that the lift and drag of a wing are just as, if not more so, important as the inertial effect of the wing structure.
This article is sloppy at best. I'm not even sure the science if that great. The diagrams certainly don't match the text, so it's tough to completely evaluate. But the bigger question is why AMA allowed it to make it through all the wickets to get in the magazine?

With the multiple duplications of text, it's clear editing either didn't happen or was poorly done. Seems to me that we're paying for a lot of MA staff members to do that, but it's clearly not done in this case, wo what exactly are we getting for our money?

It might have been the product of a rush to publication. Hard to imagine given the four month or so lead time to get a magazine out (district pages are talking about stuff that happened in summer of 2018). But even if it was a "rush" at some point, does that excuse the apparent lack of any editing? And who is being paid with our membership dollars to allow such things to be rushed?

And if it was "rushed," why? Are they that hurting for content that it couldn't wait another month for proper editing? Or is it a GOB submitted article, one that isn't subject to the editorial attention that the "unwashed masses" get when they submit something?

No matter what, the magazine Editor Jay Smith is paid with our membership dollars to ensure that sloppy things like this doesn't get published.
franklin_m is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service