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Crash Test 2
- Thread starter Fatstress
- Start date
SWComposites
Aerospace
What do you mean by "monolithic aluminum"?
The crash test was required to show equivalent safety to existing, aluminum fuselage aircraft.
The crash test was required to show equivalent safety to existing, aluminum fuselage aircraft.
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1
- Thread starter
- #4
Monolithic Alu, just the usual Aluminum sheet or plate, not laminates, ARALL, or Glare.
If I understand correctly, FAA required a full scale composite fuselage test article for the crash test. Cannot it be a smaller scale or only a few frame bays of fuselage structure only? Is there any background evidence to require such a test?
If I understand correctly, FAA required a full scale composite fuselage test article for the crash test. Cannot it be a smaller scale or only a few frame bays of fuselage structure only? Is there any background evidence to require such a test?
if think FAA were worried about the new materials introducing new effects, responding to the loads differently, being upset by different things compared with what we "know" (ie monolithic Al skins ... 2024, 7075). I think scaling only works when you're comfortable with the material and the test to know that you're scaling the right parameters correctly.
EdStainless
Materials
I want to see them break the 787 wings. I watched the 777 tests.
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Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
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Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
SWComposites
Aerospace
Yep, a little bit past ultimate load for the 777 wing test, right at the predicted failure load and location.
EdStainless
Materials
A380 didn't. They had to do a minor re-design to pass, but no re-test. I think that they made 148%. 150% is required. As I recall 777 went to 153%. They sure go with a bang.
= = = = = = = = = = = = = = = = = = = =
Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
= = = = = = = = = = = = = = = = = = = =
Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net
swearingen
Civil/Environmental
Trouble in paradise?
If you "heard" it on the internet, it's guilty until proven innocent. - DCS
If you "heard" it on the internet, it's guilty until proven innocent. - DCS
- Thread starter
- #12
RPstress,
Answer to your question can be found in the folowing link...
....dropping a 10-foot-long (3-meter) fuselage section from a height of about two stories to see how the carbon-fiber composites would hold up on impact.
Answer to your question can be found in the folowing link...
....dropping a 10-foot-long (3-meter) fuselage section from a height of about two stories to see how the carbon-fiber composites would hold up on impact.
Why did Boeing drop the 787 fuselage only 15 feet, when they dropped the 737 fuselage 30 feet? Will they drop a 787 fuselage 30 feet at some later date?
How would this aircraft survive the type of crash experienced at Pearson airport in 2005?
Would all the passengers get out after the type of fire that ensued? Building the entire fuselage from CF must be challenging from a FAR 25.853 point of view...
Steven Fahey, CET
How would this aircraft survive the type of crash experienced at Pearson airport in 2005?
Would all the passengers get out after the type of fire that ensued? Building the entire fuselage from CF must be challenging from a FAR 25.853 point of view...
Steven Fahey, CET
...And why would Boeing drop a 737 fuselage section 30 feet anyway? FAR 25 doesn't seem to have that requirement. A drop of 19 feet will give a descent velocity of 35 ft/sec, like the criteria of 25.562 (35 ft/sec). But the landing conditions in 25.473 and .723 don't require this...
Steven Fahey, CET
Steven Fahey, CET
40818
Aerospace
- Sep 6, 2005
- 459
The 737 test was to evaluate the structual effects of an aux fuel tank on the structure in a crash.
in the right hand side of the page is a pdf which will open up a report.
in the right hand side of the page is a pdf which will open up a report.
Re deadly, deadly composites (see wes616's post), see the following from COMPOSITES PROCESSING 2006 27th April 2006, "Composites in Aircraft Crashes" by John Andrews - Post Crash Management Systems.
"...when test pieces were subjected to high kinetic energy impact at the same time as high temperature (1000ºC) flame, substantial quantities of respirable fibres were released."
The author says that to get really dangerous you need both impact and high temperature simultaneously. With regard to the A340 crash at Toronto he says:
"...because any high energy impact was not coincident with the high temperature fire, there was little or no release of respirable fibres. Additionally the weather was kind and a short rainstorm each day minimised the risk from respirable dust. The overall site hazards from this crash, which were expected to be severe, were easily managed with disposable coveralls and respiratory protection."
So, not exactly nothing to worry about, but not quite as bad as it could be.
PS: ally fuses can to burn through quite rapidly when flames from the outside impinge on them (Burn-through contributed to a few of the deaths at Manchester UK in 1985 - though most were toxic gas inhalation). A carbon laminate is a lot more resistant to burn through. On the other hand, you don't want it to increase FST dangers inside the fuse. Even external materials are increasingly subject to FST regs these days.
PPS: Swearingen and Fatstress, thanks for the Boeing fuse test links.
"...when test pieces were subjected to high kinetic energy impact at the same time as high temperature (1000ºC) flame, substantial quantities of respirable fibres were released."
The author says that to get really dangerous you need both impact and high temperature simultaneously. With regard to the A340 crash at Toronto he says:
"...because any high energy impact was not coincident with the high temperature fire, there was little or no release of respirable fibres. Additionally the weather was kind and a short rainstorm each day minimised the risk from respirable dust. The overall site hazards from this crash, which were expected to be severe, were easily managed with disposable coveralls and respiratory protection."
So, not exactly nothing to worry about, but not quite as bad as it could be.
PS: ally fuses can to burn through quite rapidly when flames from the outside impinge on them (Burn-through contributed to a few of the deaths at Manchester UK in 1985 - though most were toxic gas inhalation). A carbon laminate is a lot more resistant to burn through. On the other hand, you don't want it to increase FST dangers inside the fuse. Even external materials are increasingly subject to FST regs these days.
PPS: Swearingen and Fatstress, thanks for the Boeing fuse test links.
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