Main Spar question (just curious)

[John Reinking]

I've seen where a number of different homebuilt aircraft use a box spar where the spar webbing is on both the front and back of the spar.   Would doing this with the DE main spar really increase it's strength?   

Just curious.

[Tom H]

A quick, and probably only partial answer, is that that design (box spar) is used in some aircraft.  Depending on the specifics, it could be stronger, could be heavier, too.  The Eagle design could be made to be stronger, and heavier/lighter, depending on the materials, etc..

The box spar you describe is often used to provide structure to resist twisting of the wing.  The Eagle spar does not provide much torsion structure.  The leading edge of the wing does provide some torsion structure.

Putting a box spar in the Eagles would need serious analysis.

My 2 cents.

[John Reinking]

Thanks, Tom.    Am keeping with Leonard's design but was curious about it.    The torsion twist is an issue that struck me.   No doubt that significant study would be required.    Thanks for your position.     John Reinking/Woodinville, WA

[Dan_]

Thanks, Tom.    Am keeping with Leonard's design but was curious about it.    The torsion twist is an issue that struck me.   No doubt that significant study would be required.    Thanks for your position.     John Reinking/Woodinville, WA

The DE takes the torsion in the 4 lift struts.  The d cell is lagniappes...

The DE wing has been fully analyzed by aeronautical engineers.

[John Reinking]

Thanks, Dan, again just curious.   So much to learn  about "aircraft".

[Tom H]

Dan, never heard the word lagniappes, I had to go to Wikipedia to see what it meant.  On the Eagle wings, I would have to agree with that.

[Dan_]

I took a job in Lafayette Louisiana back in the early 80's...


lagniappe 
 
 
 noun  la·gniappe  \ˈlan-ˌyap, lan-ˈ\
 
 
Popularity: Top 40% of words
 
 Definition of lagniappe
 
 
 

• :  a small gift given a customer by a merchant at the time of a purchase; broadly :  something given or obtained gratuitously or by way of good measure

  Examples of lagniappe in a sentence
 
 

• <the meal was served with a lagniappe of freshly made cornbread>
• <the hotel threw in some free shampoo as a lagniappe>

Did You Know?
 
 
We picked up one excellent word, wrote Mark Twain in Life on the Mississippi (1883), "a word worth traveling to New Orleans to get; a nice limber, expressive, handy word-'lagniappe'.... It is Spanish-so they said." Twain encapsulates the history of "lagniappe" quite nicely. English speakers learned the word from French-speaking Louisianians, but they in turn had adapted it from the American Spanish word la ñapa. Twain went on to describe how New Orleanians completed shop transactions by saying "Give me something for lagniappe," to which the shopkeeper would respond with "a bit of liquorice-root, ... a cheap cigar or a spool of thread." It took a while for "lagniappe" to catch on throughout the country, but by the mid-20th century, New Yorkers and New Orleanians alike were familiar with this "excellent word."
 

Origin and Etymology of lagniappe
 
 
American French, from American Spanish la ñapa the lagniappe, from la + ñapa, yapa, from Quechua yapa something added
 

First Known Use: 1844

Related to lagniappe
 
Synonyms
 cumshaw, dividend, donative, extra, gratuity, gravy, gravy train, bonus, perk, perquisite, throw-in, tip
Related Words
 pension; bestowal, presentation; benefaction, beneficence, benevolence, bounty, charity, generosity, largesse (also largess), philanthropy; contribution, donation, gift, offering, present; grant, subsidy; boon, manna, windfall; favor, freebie (or freebee), giveaway, premium; award, prize, reward; fringe benefit, icing
Near Antonyms
 advance, loan; bribe, douceur, peace offering, sop