Hi WKTaylor, thanks for the info. So you think the new fuse pins are 15-5 Hxxx. Any idea what heat treat?
I read this ASME report that indicated stress corrosion cracking as the initial failure. I know Boeing changed their design so that the engines do not disengage during flight but they...
Writing a presentation for stress corrosion. An illustrative example of a catastrophic event due to stress corrosion was the crash of El Al Flight 1862 in Amsterdam in 1992. Stress corrosion of the fuse pins, m/f Nitronic 60, was determined to be the cause of engine 3 disengaging from the wing...
rb1957,
Thanks for the quick response.
So would it be proper to say forming stresses are > than Fty but should be less than Ftu?
Also, all the formed parts in aircraft, including frames, stringers, etc, are they stress relieved after forming? If not are the residual stresses due to forming...
Good morning,
I am working on a 6 ft. long extrusion m/f 6061-T6511. The part is thick, 0.125 in.
The part must be bent to a large radius. The max offset from horizontal is nearly 8 in.
Currently, the drawing has the part formed in the -T6511 condition. The drawing also has a note that...
I am a 30 year stress guy. While at Boeing in the 90's, I took advantage of a Boeing program through the University of Washington & I obtained a Master of Science in Mechanical Engineering. My lead back then was a German stress guy & he encouraged all his young protégés, me included, to...
Assume you are looking at allowables for the inserts and panels.
I attached brief FAA guidance on design values.
Need to account for materials from different lots (panels), as well as installation by different mechanics (inserts).
For inserts, the typical batch is 15, with samples made...
Crippling is a method that the analyst employs when he or she has made the determination that a bent-up or formed composite section has post buckling strength (it must be able to take further load at the corners of the section after individual segments have buckled – for a bent up section, the...
Aircraft interior. Bin support fitting. Modeled as solid with Tet-10's.
Von Mises stress exceeded Ftu on linear run.
Input stress strain curve and ran as static non-linear.
Non-linear output doesn't include Von Mises stresses. Output does include max & min principle, max shear, X-Y-Z...
Best to consult the SRM (structural repair manual) for the aircraft that you are working on. If you abide by an SRM repair, you are covered for flight and ultimate loads, damage tolerance, and fatigue.
