If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Testing Stick-built Ribs
Hi Guys.
Does that title tickle any memory-bones? Well, let's see if I can tickle them again. First-off come the ground rules: The data came from "Handbook of Instruction for Airplane Designers, Structures Tests" Air Corps, U.S.Army (Not available to the public) ....and apparently not available to many Airplane Designers, too. :-) (Because nobody could remember seeing the thing.) Okay, start with the outline of whatever airfoil you're working with... which tells you right off that this isn't going to be good for ALL airfoils. The airfoil used in the Army manual looks suspicious like the USA-35B, which was used in the Piper Cub... and was the first thing C.G.Taylor tossed on the rubbish heap when he designed the Taylorcraft. However, the Army's test wing was tapered and of aluminum construction. It would be interesting to know the history of this manual since, from all appearances it didn't do the Army Air Corps much good. Using whatever outline you're using, starting at the trailing edge, come forward 10% of the airfoil's chord. The next section takes 43.8% of your airfoil's length. Next comes the main load-bearing section: 27.1% of your airfoil's chord, and finally the leading edge section -- 19.1% of the airfoil's chord. The weight is distributed as follows: 20% is suspended on the leading edge section, 40% is suspended on the mid-wing section, and 40% is suspended on the aft-wing section. You will note that NO LOAD is placed on the trailing edge of the wing. The method is a bit unusual (in my opinion) but it matches the |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
veedubber what do your ribs weigh? | Stealth Pilot[_2_] | Home Built | 11 | January 2nd 09 12:59 AM |
Cooking Airplane Ribs | [email protected] | Home Built | 4 | December 6th 07 09:39 PM |
Cracked ribs | Jack Allison | Piloting | 17 | April 1st 06 09:14 AM |
Cracked ribs | Jack Allison | Owning | 6 | April 1st 06 09:14 AM |
Testing Stick Ribs | Bob Hoover | Home Built | 3 | October 3rd 04 02:30 AM |