Testing On The Cheap

performed static testing on Saturday. Went well except engine mount broke
(§&%!?$ one of the few parts I didn't fabricate by myself) So far about
testing.....

www.ph21.de/guest/Pict0035.jpg



"gorgon" schrieb im Newsbeitrag
...
On Jul 3, 10:49 am, "rattlesnake" wrote:


Destruct static testing done in a non-silly and relevant manner. Kind
of cool to see that they predicted the failure mode and location. The
wing was designed within a couple of percent of the goal. No weight
sacrificed here.


http://www.youtube.com/watch?v=pe9PVaFGl3o

rattlesnake schreef:
(§&%!?$

You are strong at foreign languages, mein lieber Herr! Bravo!
But then, cursing is always learnt first, isnt'it...?

if you just scrapped a $1000 item wouldn't you, mon ami?


"jan olieslagers" schrieb im Newsbeitrag
...
rattlesnake schreef:
(§&%!?$

You are strong at foreign languages, mein lieber Herr! Bravo!
But then, cursing is always learnt first, isnt'it...?

Ouch,
glad THAT didn't happen in the air.


Seeing an engine depart must be on about the same excitement level as
seeing aeroelastic vibration in the wing tips.
Makes me think of a reason why I sometimes see a wire cable tether round
a couple of engine fixings back to a bulkhead. A loose engine has a
better CofG that a missing engine, no doubt!

Brian W


rattlesnake wrote:
performed static testing on Saturday. Went well except engine mount broke
(§&%!?$ one of the few parts I didn't fabricate by myself) So far about
testing.....

www.ph21.de/guest/Pict0035.jpg



"gorgon" schrieb im Newsbeitrag
...
On Jul 3, 10:49 am, "rattlesnake" wrote:


Destruct static testing done in a non-silly and relevant manner. Kind
of cool to see that they predicted the failure mode and location. The
wing was designed within a couple of percent of the goal. No weight
sacrificed here.


http://www.youtube.com/watch?v=pe9PVaFGl3o

"Brian Whatcott" schrieb im Newsbeitrag
...
Ouch,
glad THAT didn't happen in the air.

wouldn't happen in the air. Was caused by stupid static load testing.....

rattlesnake wrote:
"Brian Whatcott" schrieb im Newsbeitrag
...
Ouch,
glad THAT didn't happen in the air.

wouldn't happen in the air. Was caused by stupid static load testing.....


I'm thinking it would be stupid, or at least careless, if the load
were reacted through just one or two mount fixings.
Is that how the test was rigged?
(I noticed there seemed to be a steel strip
perhaps 3/16 X 1 inch welded into the cluster which seemed to
provide a rather abrupt section change.) Is that the way the plans
were drawn?

Brian W

"Brian Whatcott" schrieb im Newsbeitrag
...
....
I'm thinking it would be stupid, or at least careless, if the load
were reacted through just one or two mount fixings.
Is that how the test was rigged?

roughly the setup was like this:
- plane upright
- tail and elevator loaded by about 430 lbs of bricks
- ailerons and flaps loaded by about 290 lbs of bricks
- both wings supported by 1.5 ton car jacks
- engine pushed down by about 1.100 lbs at position of the four attachment
points

I got a bad feeling before the test, but I have only two choices in my
country:
1: do this silly static test
2: reject it and never receive the permit to fly

I think the lower attach points can be repaired. Probably solid 3/4" rond
bars will be welded into the remaining tubes. However I lost some of my
confidence in this flying machine because I don't know what (invisible)
secondary damage may have occured.