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Old Jun 23, 2013, 12:49 PM
Pilot Mike
Lost Oracle's Avatar
United States, NM, Moriarty
Joined Oct 2009
150 Posts
Whoops!
User error or an aging airframe?

I was out flying my Blaster 2 this fine morning, then disaster struck. On my 5th launch of the day, as I swing the plane around, and suddenly all that tension in my arm went limp. My wing had snapped and the plane plows into the ground.

My first thought was, "Wow I've got a strong arm"

Second thought goes, " that was my only DLG"

So heres my question, is it possible that my throw just surpassed the structural integrity or did I do something wrong that I could have avoided. In other words, how often do you see someone break a wing in half due to launch.

It was an older B2 that has seen a lot of abuse (it was my first DLG) so maybe it was just time for it to go. Now all I can do is wait for my SuperFr3ak order to arrive. Should be any day now...

P.S I may be in the market for a new 'beater' plane
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Old Jun 23, 2013, 02:37 PM
Registered User
United Kingdom, Banstead
Joined May 2013
340 Posts
tis a mere scratch...bit of duck tape and she'll be as good as new...

sorry to hear that another dlg bites the dust, never a good feeling when that happens..I'm sure someone will be along to tell you they've fixed worse.

Dave
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Old Jun 23, 2013, 06:55 PM
let's FLY!
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United States, VT, Castleton
Joined Dec 2007
2,061 Posts
That will buff right out.
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Old Jun 23, 2013, 06:58 PM
let's FLY!
JimZinVT's Avatar
United States, VT, Castleton
Joined Dec 2007
2,061 Posts
Hey, someone had to say it That's a bummer; looks like it was in decent shape.

Maybe a minor tip strike on a previous launch tweaked it, and it blew up on this throw?
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Old Jun 23, 2013, 10:38 PM
Will fly for food
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Bellevue WA,
Joined Dec 2003
6,729 Posts
Any hard landings? Are you prone to throwing up at high angles?
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Old Jun 24, 2013, 01:47 AM
Alex Hoekstra's Avatar
Hurdegaryp Netherlands
Joined Feb 2007
384 Posts
Pretty sure this was a tip strike. When a wing gives up it would just fold but stay together. Your wing is ripped from leadingedge towards trailingedge. Something like that only happens with tipstrikes.
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Old Jun 24, 2013, 02:53 AM
He bowls overhand
threcixty's Avatar
Falcon, Colorado
Joined Oct 2004
1,557 Posts
If you're a lefty, tip strike. If you're a righty, well, probably tip strike. Do you throw level or upwards?
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Old Jun 24, 2013, 08:32 AM
Pilot Mike
Lost Oracle's Avatar
United States, NM, Moriarty
Joined Oct 2009
150 Posts
I throw pretty level. I'm confident its not a tip strike, I never came close during the last year of owning the plane (plus theres no visible damage where the tip would have struck.

However, like David mentioned, there was this one hard landing that happened a few days earlier. The plane lawn darted after a flap malfunction and caused some damage to the nose cone. I thought the damage was isolated to the nose area but when it hit the ground the plane made a distinctive carbon breaking noise. At the time I didn't think much of it. I should have checked it closer but I think the main spar may have been compromised before the first throw.
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Old Jun 24, 2013, 08:42 AM
Pilot Mike
Lost Oracle's Avatar
United States, NM, Moriarty
Joined Oct 2009
150 Posts
Quote:
Originally Posted by Alex Hoekstra View Post
Pretty sure this was a tip strike. When a wing gives up it would just fold but stay together. Your wing is ripped from leadingedge towards trailingedge. Something like that only happens with tipstrikes.
Alex provides some compelling evidence for a tip strike, but I'm still unsure about it. A lot of the damage is secondary after the wing had folded and ate dirt. It broke right as I started to apply power about half way through my swing.

When the spar crapped out my arm was still committed to throwing it as hard as I could which would have seriously torqued the loose left wing and torn the skin apart. I'll definitely take a look at the left time for any evidence of ground contact. I also had a witness who saw the plane explode who might be able to say whether or not its possible a tip introduced itself to the ground.
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Old Jun 24, 2013, 10:05 AM
Registered User
United States, MD, Baltimore
Joined Feb 2007
644 Posts
Sorry man but that is a tip strike. Look on the right aileron about 3-4inches in. See the compression fracture at about a 45 degree angle on the top of the aileron? That's what happens when the wing tip try's to make friends with the tail.

Tip strikes rarely leave any evidence on the outboard tip and happen to the best of us. They happen too fast to feel and mostly are discovered because of the damage you are seeing or someone else seeing it. I saw Kyle Clayton blow up an xxlite at the Bruce last year because he was launching on the hill and didn't realize the backswing was uphill.

Good thing is everything is fixable. If you don't want to bridge the gap cut both wings down and rejoin for a great 1m plane.
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Old Jun 24, 2013, 02:25 PM
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Congress, AZ
Joined Sep 2001
4,874 Posts
It seems like many times it doesn't break when you actually strike, but a later launch.
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Old Jun 24, 2013, 06:16 PM
hass-alfed and bass-ackwards
carlsoti's Avatar
United States, AZ, Chandler
Joined Jun 2008
5,297 Posts
One of the local guys that used to fly DLGs with us blew up a number of B2s with "not a tip-strike" launches. I don't ever recall seeing "evidence" on the tip, but regardless, his wings blew up. Unless you've videoed your launches, and you launch more or less the same EVERY time, you're probably getting closer to the ground with the wingtip than you realize. I'm guilty of this myself.

If you've beat it up a bunch, it's possible it just gave up, but even beat up blasters are usually pretty durable, if the repairs were done correctly.
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Old Jun 24, 2013, 06:27 PM
He bowls overhand
threcixty's Avatar
Falcon, Colorado
Joined Oct 2004
1,557 Posts
Maybe the spar broke on the outer wing, and allowed it to fold down into the ground from the aerodynamic loads on it.
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Old Jun 24, 2013, 07:38 PM
Registered User
Germantown, Maryland
Joined Apr 2004
4,511 Posts
All of the evidence is consistent with a tip strike. Even the owner of the plane denying the possibility of a tip strike is entirely within the normal pattern of new guys learning about tip strikes.

A long time ago, near the dawn of the DLG age, even I was a newbie to DLG launching. I blew up three or four planes with tip strikes before I figured out what was happening. I didn't have anyone around me at that time to take me aside and explain about tip strikes. I had to learn the hard way. When that third or fourth plane tip struck so hard that it turned into a loosely connected collection of airplane bits tumbling along the ground at high speed, it finally dawned on me that the plane was not at fault, I had simply asked the plane's wing tip to do something that should more appropriately be done with farming implements.

It is normal that throwing technique gradually changes over time and that you gradually, without realizing it, begin to throw the plane into a more upward trajectory. As you do this, the wing tip gets lower and lower on the back swing until you get some clue about what is happening. If you are lucky, the clue will be a loud clicking or cracking noise. That noise is the sound of the wing tip clipping the grass. You likely will perceive the noise as happening at some later point, like after release for instance. If you don't correct your swing, the next thing that will likely happen is that you will post pictures and questions on RCgroups and we'll all get to read another tip strike thread.
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Old Jun 24, 2013, 08:08 PM
a.k.a Frank Campbell
Long Beach, CA, USA
Joined Jan 2007
699 Posts
From the original posting

Quote:
Originally Posted by Lost Oracle View Post
I was out flying my Blaster 2 this fine morning, then disaster struck. On my 5th launch of the day, as I swing the plane around, and suddenly all that tension in my arm went limp. My wing had snapped and the plane plows into the ground.
When I blew up my XXLite I snapped the wing clean through about 3 inches from the fuse on the non-throwing side. I didn't hear anything that I recall. At first I thought that the throwing peg had come loose because the tension on the peg went away as I was swinging through. Makes sense. If you hit the tip then the ground is taking the load briefly rather than your fingertips.
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