Wing Failure???

[Kelly]

Well had a great first flight with my Boomer, second flight this was the ending

Half throttle,half roll into a 45 degree  dive pulled up to do a roll off the top, crack the  left wing failed at the point where the skinned balsa centre section ends and becomes the open framework of the wing ?? went vertical into the ground and returned to kit form.

Did not do a sudden pull up ( control settings still on low)  not going very fast

No previous damage to wing ,10th flight of model.

I will have to look for the right wing tommorrow , it came down in the trees ,had a look today failed to find it .

Few pics of the break in the wing.

Anyone think it would be worth having a word with seagull, has anyone had the same problem ??

Kelvin  

[Hamish]

Gutted for you.

I have a Boomerang as well and it has only had 3 flights with no problems.  My concern was that the fabric can easily be punctured but I did not think of wing failure.  Will be on tenterhooks from now on.

Cant say much more other than too late for the pub

edit Speeeling

[David Ashby - Moderator]

Sorry to see that Kelvin, a very unusual thing to happen on a model like that? I guess it doesn't do any harm to have a word.

[Andy Harris]

I've seen the same Boomerangs fly week in week out at our club.  They seem supremely durable.

Andy

[Tim Mackey]

Very sorry for you Kelvin - its a bummer....but all part of the game I am afraid

[Kelly]

Thanks guys.

Good news is the engine ,three servos, switch ,receiver and Rx battery all survived intact .

Found the right wing while walking the dog this morning.

Underside showing point of failure. Looks like the main spar bit failed first ,was really quite spectacular

Kelvin

[Adrian]

It's really bad design having a stress riser like that. I saw a Boomerang meet its demise in a similar way the other week. Father and daughter were buddy boxing. Daughter was having fun looping; she wan't too interested in level flight. The airplane was heading for the ground so father took control and pulled the stick back. The wing snapped just at the end of the wing joiner.

 Sorry, but Boomerangs are not built for aerobatics.

[Kelly]

Hi Adrian,

Thanks for the input,we live and learn .

The Boomer is descibed as a sport trainer, the wing section is semi-symetrical this to me  implies that it is capable of aerobatics.

I think the lesson here is to treat it as a trainer at all times and just stick to mild aerobatics.

I still think it is a good trainer,when it keeps its wings on .

[Bruce Richards]

I have had a Boomer for 2 years and done lots of aerobatics with no failures. When I was learning my instructors taught me to keep it smooth and anytime I didn't thay said "the wings will clap if you do that". So I have learnt to keep it smooth. You may just have had a bad one so do not judge them all but this one.

[001]

Kelvin. From past experience with a poorly constructed ARTF, strip all the covering off,have a good look at the structure, particularly the wing. IF there is evidence that the structure has not been glued, or there are gaps in the basic airframe, or knots or defects in the wood,  take some good quality photos, send them with an explanatory letter (not threatening) to the importer, stating the facts and see what happens. You should be able to practice basic aerobatics with a trainer, that is what they are for.

[Tim Mackey]

If you are on 35 Mhz, you may also want to consider a new crystal - they are actually pretty delicate items, and it could be damaged ( invisibly ) from the impact.

[Kelly]

It is very hard to tell if any defects are present it is so ripped apart,I will be contacting the distributers to see what they think.

I fly very smooth and I keep the speed down,it was on dual rates but I have never used the so called aerobatic setting as the normal trainer mode is more than enough for smooth aerobatics.

 I also fly a Ripmax EP Spitfire and Me109( now I can hand launch) so I like to fly at lower  speeds to emulate the full size aircraft .

I am using 2.4 Futaba gear so it should be okay. Will test everything well before fitting to another model.

It was my cheapest airframe so I will not spend too much time trying to prove it was defective. Like any product that is put together by someone else, you will always find the odd  one or two with defects/ poor workmanship. 

I think it is worth pointing out that some of us may have lost Boomers to structural failure so maybe Seagull could have a look at their quality control??

The Blackhorse super air looks nice for my next model,wonder what bits might fail/fall off that

I wish I had the time to build ,then I would know what lurks beneath the covering .

Cheers guys

Kelvin

[Former Member]

[This posting has been removed]

[Kelly]

Hi Eric,

Yep photobucket has been changing things, sometimes pics do not copy??. Same pics different angles may repost later.

In a model of this size and a trainer to boot ,I would use more robust spars and wing ribs even if it made it a tad heavier . Wish I had the time and space to do a traditional build,like I did as a Lad

[Former Member]

[This posting has been removed]

[Kelly]

I Wish Eric .

1974 I think

Model Veron Fokker D8 Tissue covering

Engine Webra 2.5 diesel

Radio McGregor 2 channel  Rudder/Elevator

[john powles]

Hi Kevin I recently saw the remains of one of these models recovered from our flying field it was in a similar state to yours only a little more so , it had been abanded by its owner where it went in -left for others to clean up wether it had suffered wing failier or pilot error we could,nt tell but it was irisponsible to leave it for others to clean up the mess.

[Kelly]

Hi John,

I agree with you.

I always take a selection of bin liners .

Mainly for used paper towels and to keep my Tx and other bits and bobs dry on the wet grass.

Used two to collect the remains of the Boomer .

Kelvin

[Ralph Yeates]

Kelvin the spar wood does not seem to be the best quality I have seen, I think these kits from the far east are on the limit with a little bit of lee way but not a lot. The whole kit is usually very light construction and the minimum of extra reinforcement. I think that you may have had a weak spot which you would no have seen as the kit is pre covered and everything came together and it just gave way. Just my opinion, any way here is some thing to cheer you up here is my bothers Ultimate where the elevator linkage came off it just exploded on impact.

[Kelly]

Hi Ralph,

Thanks for your observation. I agree the wood is not the best quality.

I am taking the wing to the shop I purchased it from . The owner is a seasoned modeller who knows his stuff when it comes to model construction .

Your Brothers Ultimate is a sad sight . Hope the engine is okay and the radio gear.

Still got my Spitfire and Me109 to play with and my P-40 is not far from being flight ready .

Kelvin

[Kelly]

A bit of an  update.

 

Many thanks to J Perkins ,they have replaced my Boomerang with a brand new one.

 

On the new Boomerang the plywood wing joiner has been replaced with a aluminium tube,

 

So all you Boomer owners with the old wing joiner be careful not to put too much stress on the wing during aerobatics, some of us have become wingless .

 

Kelvin

[Alex Leigh]

Oh missed your last post. Good news I still think the first one'll buff out tho!

[Stephen Grigg]

I have a Boomerang that is fairly new,so you have me a bit worried.Iflew a seagull Pineer during the summer and broke everything except the wings,and I have apair still wrapped up.The models are similar except for the wing fixing,but Ull chat to my instructor for advice.Ive nearly finished buildind a Flair cub so maybe ill continue with that.

[Kelly]

Hi Stephen,

 

I would not worry too much, lots of people have Boomers and they are OK, I just got a duff one. 

[Stephen Grigg]

Thanks Kelvin