Stinger 120 - Weak point in fuselage ???
08-08-2003, 10:55 AM
#1
Thread Starter
My Feedback: (2)
Join Date: Mar 2003
Location: Holbrook, NY
Posts: 51
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
Stinger 120 - Weak Point !
Hi Guys-
I built a Stinger 120, Full wing (80"), w/ OS Surpass 120, Pitts muffler. I had a hard landing at the flying field and the fuselage broke completely in half at a very unusual point. The area where the fuse broke is along the fuse side, left and right, where you have to "score" the fuse side in order to make a "bend", just aft of the wing hold down bolts, and the front edge of the "aft" most turtle deck. I've studied the break, and this vertical score makes the body of the aircraft very susceptable to disassociating the front from the back, as it did with mine. Q: How many of U have started an engine and stood with your legs supporting the plane with your ankles chocking the plane and running engine, by only the leading edge of the stabilizer? I thought about this, and wondered if the front fuse might ever pull in half-from the back of the fuse, one of these days, with another modeler. During construction, I reinforced the F3 with 1/2" triangular stock-both fore-and aft, and sheeted the bottom according to the plans. The weakness of this area is contributed by the fact that the triangular stock along the fuse bottom, is also sawed and trimmed to make this "bend". But, there really isn't much longitudinal support at this, a seemingly critical, point of the fuse. I don't know if Bubba S./ Lanier Aircraft, reads our forums, but I would be interested on how they are dealing with this building imperfection. Or, what other builders are doing to reinforce this weak point. Also, any comments from the ARF Stinger 120 fliers?
All Comments Welcome, while I consider how to mend the fuse!
Happy flying all.
Jim Soque
OF NOTE: The entire rest of the plane is completely inscratched, didn't even a nick the prop!
To view photo of complete plane, click "gallery" below.
Hi Guys-
I built a Stinger 120, Full wing (80"), w/ OS Surpass 120, Pitts muffler. I had a hard landing at the flying field and the fuselage broke completely in half at a very unusual point. The area where the fuse broke is along the fuse side, left and right, where you have to "score" the fuse side in order to make a "bend", just aft of the wing hold down bolts, and the front edge of the "aft" most turtle deck. I've studied the break, and this vertical score makes the body of the aircraft very susceptable to disassociating the front from the back, as it did with mine. Q: How many of U have started an engine and stood with your legs supporting the plane with your ankles chocking the plane and running engine, by only the leading edge of the stabilizer? I thought about this, and wondered if the front fuse might ever pull in half-from the back of the fuse, one of these days, with another modeler. During construction, I reinforced the F3 with 1/2" triangular stock-both fore-and aft, and sheeted the bottom according to the plans. The weakness of this area is contributed by the fact that the triangular stock along the fuse bottom, is also sawed and trimmed to make this "bend". But, there really isn't much longitudinal support at this, a seemingly critical, point of the fuse. I don't know if Bubba S./ Lanier Aircraft, reads our forums, but I would be interested on how they are dealing with this building imperfection. Or, what other builders are doing to reinforce this weak point. Also, any comments from the ARF Stinger 120 fliers?
All Comments Welcome, while I consider how to mend the fuse!
Happy flying all.
Jim Soque
OF NOTE: The entire rest of the plane is completely inscratched, didn't even a nick the prop!
To view photo of complete plane, click "gallery" below.
08-08-2003, 09:08 PM
#2
Junior Member
Join Date: Feb 2002
Location: Cape Neddick, ME
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
Have had the same thing happen to me on a stinger 10 while doing a tight inside loop. It broke in half. I couldn't believe my eyes. I willl build another one, however I will reinforce The wing saddle area with fiberglass.
Lugnuts
Lugnuts
08-08-2003, 10:45 PM
#3
Senior Member
Join Date: May 2002
Location: Oxford, GA
Posts: 202
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
The usual break point has seemed to be the front of the wing saddle on stinger crashes at our club (we have lots of stingers).
I'm building #4 of the 120 size currently and have never scored the fuse anywhere for construction through fear of weakening it just as you describe. I also always use foam covered with balsa to make the turtle deck secured well to the fuse. My personal stinger is a gasser, but two of the others constructed for club members have been powered by OS 160's and fly well.
Sorry to hear of your problem - the fiberglass idea or a ply scab secured with probond are both excellent ways to repair.
Good luck,
Dave
I'm building #4 of the 120 size currently and have never scored the fuse anywhere for construction through fear of weakening it just as you describe. I also always use foam covered with balsa to make the turtle deck secured well to the fuse. My personal stinger is a gasser, but two of the others constructed for club members have been powered by OS 160's and fly well.
Sorry to hear of your problem - the fiberglass idea or a ply scab secured with probond are both excellent ways to repair.
Good luck,
Dave
08-09-2003, 10:35 PM
#4
My Feedback: (1)
Join Date: Dec 2001
Location: Dallas, GA,
Posts: 335
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
Interesting... I just finished building a Stinger 120 a couple of weeks ago and did not score the fuselage to achieve the described bend. That to me would be absolute no-no because of the brittleness of the fuselage sides (1/8" lauan door skins - hard and rough).
I just went back and looked at the plans and instruction manual. The instructions don't call out to score the fuselage sides. How old is your kit?
I just went back and looked at the plans and instruction manual. The instructions don't call out to score the fuselage sides. How old is your kit?
08-10-2003, 11:28 AM
#5
Senior Member
My Feedback: (5)
Join Date: Dec 2001
Location: in,
FL
Posts: 1,924
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
The normal break point (Most of them will ) is at the leading edge of the wing saddle. This applies to all Stinger sizes.
Just look at the fuselage from the side and you will see it's weak point.
It needs to have a doubler installed from F2 back past the trailing edge of the saddle.
I have never seen a stinger break past this point, unless there was good reason, like excess gravity that day...
Just look at the fuselage from the side and you will see it's weak point.
It needs to have a doubler installed from F2 back past the trailing edge of the saddle.
I have never seen a stinger break past this point, unless there was good reason, like excess gravity that day...
08-16-2003, 01:15 AM
#6
Junior Member
Join Date: Jul 2002
Location: York,
ME
Posts: 16
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
Mine broke at the leading edge of the fuselage. I emailed Lanier about my discontent and this is the response that I received.
"...the Stinger 40 has been out since 1994. Out of the thousands sold, it seem very strange that you are the only one that has a problem with it. It takes a different building technique to work with the BPPF kits. Maybe you should stay with the conventional wood kits.
Customer Service
Lanier R/C Inc. "
Apparently, they are not on the web yet.
"...the Stinger 40 has been out since 1994. Out of the thousands sold, it seem very strange that you are the only one that has a problem with it. It takes a different building technique to work with the BPPF kits. Maybe you should stay with the conventional wood kits.
Customer Service
Lanier R/C Inc. "
Apparently, they are not on the web yet.
08-25-2003, 10:15 PM
#7
Junior Member
Join Date: Aug 2003
Location: Sapulpa, OK
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
I had a Giant Stinger with A Zenoah G-62 And it did the exact same thing on a hard landing. I have been considering getting a 120 size for my OS 160 twin And I wonder if the ARF version would Exhibit the same problem. I think I will reinforce the area in question regardless whether kit or ARF.
08-25-2003, 10:28 PM
#8
Senior Member
My Feedback: (5)
Join Date: Dec 2001
Location: in,
FL
Posts: 1,924
Likes: 0
Received 0 Likes
on
0 Posts
Stinger 120 - Weak point in fuselage ???
By all means, reinforce it. You will be glad you did.
I had a 120 size and reinforced it, banged the crap out of it but it never broke there.
I had a 120 size and reinforced it, banged the crap out of it but it never broke there.
