An Airplane Story from My Facebook Page

Yes, I remember your post, Kim, can't recall exactly where, haven't searched, may have been in another model airplane forum. Didn't know you were part of the ground servicing crew. Yes, with that buckling of the main wing spar, plus wouldn't be surprised of all the popped, cracked riveting, can understand why the airframe overall except for a few places didn't have much salvageable left except for engines, landing gear and some of the other mechanical / electrical parts.

C-17 Main Wing Spar Fatigue Test

The buckling reminds me of the C-17 Structural Testing Program in the late 1980's at Douglas Aircraft Company in Long Beach, CA where I worked on the 2nd floor of the 4 story high auxiliary admin building 41A attached to Test Hangar 41. (2nd story was actually 3 stories high. 3rd floor was both flight test and structural test engineering offices. 4th floor was the flight test control room and more engineer offices, some manager offices. Equivalent to 1st and 2nd floor of 41A was the Simulations Lab. In the main room, they had a portion of I think the DC-10 cockpit, used to work on software there quietly as much of the time it was unoccupied.)

On the hangar floor, one of the tests they were doing was the C-17 main spar section passing through the fuselage. In a test jig, they had million pound hydraulic actuators with all sorts of instrumentation hooked up, strain gauges, etc. to measure movement and internal metallic strains.

With roped off guards around to keep traffic and people away, there was also a sign posted stating the brief title and test number, component involved, flight numbers, "Keep Away", "Test in Progress", etc. Because I was badged as part of the testing staff, I was permitted to walk the floor and observe the test in this high security area (when test in progress). Even went in the adjacent test trailer with our Perkin-Elmer 3220 minicomputer there (it did both the loading and data capturing), looking over the computer operator's shoulders.

The system had fail safes throughout. Tests were sometimes around the clock with 3 shifts. Sometimes it was just two shifts with a shutdown during 3rd shift. (Depended on schedules, priorities and cost.) It was amazing to watch the test in action. Basically these hydraulic actuators would apply pressure, then release, done in an accelerated manner to simulating thousands of hours of stresses to be encountered during the life time, or several life times of the aircraft. We used the same data system to both apply the predetermined loads through a spectrum tape, loaded before the test began. Then, test would run for days on end. Periodically, data sets from our recorded data tape to the structural engineers, for their evaluation.

Continuing months on end, when the test specimen finally fatigued to the point of serious yielding, sometimes even total fracturing with clean breakage, the sound was a loud "boom!" heard even inside the building, system would dump hydraulic pressure and shut the test down.

My Sterling Minnie Mambo Spar Failure

My Minnie Mambo suffered structural wing spar failure back in the late 1980's, when I was still working there. Previously, I had crashed my Minnie, but didn't know the wing spar had been weakened by the crash.

To blow off steam, I'd take a 3 day weekend and head up to Santa Maria up north, a couple hour drive along scenic Highway 101. (Passed through a Santa Claus village on the way up.) Take my half-A medium flight box and Minnie. Fly at a secluded park portion on Vandenburg Air Force Base. I was doing my wild spiral dive with the Cox .049 R/C Bee screaming with muffler cover off. Just when I neutralized Minnie about 50 feet above ground and was executing the start of a loop, the spar in one wing panel failed, sending Minnie into a lawn dart corkscrew.

Rest of the damage was superficial except the broken spar. Repaired the spar, recovered affected wing panel with silk and clear dope. Several weeks later was back at it again, with Minnie as strong as ever.

That was my single days without a yard to take care of and otherwise without a care in the world except for my R/C planes.

Cool beans, Kim. That classic tug with the cool name on it almost demands to be modeled with a dog in the passenger seat.

I was searching the net for a photo of the old building I used to work in, Test Admin Building 41A adjacent to Test Hangar 41, located on the northwest side of the airport. Historic photos of Douglas Aircraft Co. are now available at the Library of Congress:

https://www.loc.gov/search/?in=&q=douglas+aircraft+%22CA-315-L%22&new=true&st=gallery

But, documents contain no photos of Hangar 41 nor 41A. They were built less than 50 years prior to the photos taken, not considered historically significant (built in the mid 1960's).

Around 2002, Boeing sold the DC-10 / MD-11 commercial manufacturing properties except DC-9 / MD-90 program (now Boeing 717) on the north side of the airport, east of Lakewood Boulevard. I have photos stashed somewhere of the piles of construction debris inside a temporary construction fence on the north side of the airport, taken that Fall when I returned to the area for additional continuing education training.

2006, last DC-9 derivative, Boeing 717 rolled off the assembly line.
http://s80.flight1.net/forums/fly-dc-jets_topic1039.html

Courtesy of flight1.net Forums.

Now, one of those large manufacturing hangar buildings not demolished is operated by Mercedes Benz. (Perhaps a historic preservation move?)

2015, last C-17 rolls off the assembly line.



2018, Boeing sells off all C-17 manufacturing facilities on the south side of the airport.
https://www.thedrive.com/the-war-zone/24774/boeing-is-selling-off-its-historic-c-17-production-line-facility-in-long-beach

Now, Boeing does all C-17 overhaul and refitting in San Antonio, Texas:



Another aerospace company now occupies those C-17 facilities at Long Beach. Douglas Aircraft Company of Long Beach, CA is no more. Do I miss it? No, knowing where your next paycheck is coming from, going home from work on time, and having holidays off is more important.