Gordon Mc

My Feedback: (11)

Agreed.

Additionally, the directive posted earlier in this thread states:
From the pic posted in [link=http://www.rcuniverse.com/forum/fb.asp?m=9752266]post #8[/link], it appears that the wing that failed here is from serial # 104 (?) - that's outside of PST's range of serial numbers that they say are affected by the manufacturing defect. In other words, it appears this wing should not have been at risk for this defect, based on PST's explanation of the problem.

Gordon

TURBOMC

My Feedback: (7)

Sorry Dreamer! I didn't think that was really relative to this thread considering the failure mode. Here ya go anyway! From what I can ascertain there are 6 ribs, one main spar and one on the trailing edge. Two joiner tubes. The main tube,1" diameter aluminum,extends into each wing half about a foot and the smaller one, 1/2" diameter aluminum, extendsinto each wing half about 6". There are 3 ribs supporting the main tube receiver however, rib #3 is heavily cross braced to rib #4 by the retract mounting plate (1/2" plywood I believe).

TURBOMC

My Feedback: (7)

Great sleuthing Gordon! I hadn't noticed the serial number cut off. Stupid me thought the serial number on minewas R10A. If this wing was outside of the serial numbered wings that had the seam problem I wonder why, as appearences would have it, mine split?

LGM Graphix

My Feedback: (22)

Gordon,
I had no idea about the serial number mentioned, in this instance, I think it would be right of PST to offer something up.
Funny though isn't Gordon, a chinese wing has a crack and it fails. That Raptor wing has a crack and it holds up to anything!

Gordon Mc

My Feedback: (11)

Let's hope it stays that way ! The first wing I got with that Raptor had the tip broken off in shipping, which let me see the structure inside - and that showed that the spar was only glued to ONE surface, because the bead of epoxy that was applied to the other surface was in the wrong place ! (Why they applied the glue to the skin, rather than the spar, is beyond me). That didn't really inspire a lot of confidence.

Gordon

LGM Graphix

My Feedback: (22)

Geez why'd you tell me that LOL!!!!

Only problem I have had with the Raptor was the plastic main gear flex plates both broke at the same time when I applied the brakes on landing! The landing was beautiful, it was fast, but a very gentle touch down, hit the brakes and both gear came out of the wing with the flex plates in about 10 pieces LOL Serve's me right for not changing 10 year old plastic parts anyway

Sonicwings

I thought i had seen reference to early production kits/numbers... Well done Gordon.

My kit is no 134... yes i checked inside the wing, as best one can see, and yes it appears to have glue on the joints, i dont read the AD, as to i HAVE to tape my LE, OR for that matter did early kit owners.
This is the first i have heard of a total failure and resulting writeoff, but is sure making me nervous about mine now...

Whatever way i look at this, PST Need to comment, and come to the party, helping replace... IMO...

Jeremy.

David Gladwin

Some informed opinion, no, facts.

I have a PST Reaction (088) which flies superbly with its PST 1300. When I received the kit, I inspected as much of the structure as was possible, visible, and I was VERY happy with it. It was FAR better than a certain Delta I have which was "built" at another Thai factory (I still have that airframe, now suitable corrected) in case anyone queries that statement.

I subsequently badly damaged the wings of the Reaction in a forced landing in bushes (totally my fault, finger trouble with my laptop when programming my new Weatroncs 2.4) so I was able to take a look at the internal structure and construction, which would otherwise not have been possible, again it looked absolutely fine, very well made, in fact.

Last March I visited the new PST factory in Bangkok when my cruise ship night stopped there. You will not find a more enthusiastic , more dedicated group making jet products and Kraivuth explained that he flies his Reaction, with a PST 1600 VERY HARD with the specific aim of trying to discover any possible weaknesses in the airframe BEFORE customers do. It is in fact the "lead ship" in fatigue testing, they are a very consciencious team. So far it has held up fine so customers should have no problem. That said we live in an imperfect world, and he did issue an AD to check and tape the leading edge, seems a good and totally reasonable idea to me, full size manufacturers do it all the time. You can test to destruction at the factory, but the REAL test is when customers get hold of them !

That said, I do cringe when I see how some modellers treat their airframes often grossly overpowered, flying them in a totally unneccesary and aggresssive, hard, manner with absolutely no consideration to the fatigue and stress they are putting on the airframe. An example is the recent high powered electric jet (which I am sure was designed and built to the highest standards) disintegrate in flight. , the operator states he was doing flat out runs followed by HARD pull ups, (obviously beyond, the top right of the flight envelope of this jets) and eventually the airframe through the towel in, why should anyone be surprised, EVERY structure has its limits ? I even see people posting on here saying that airframes should be strong enough to tolerate full control deflections at max speed, are they kidding ?? Why do they think fullsize jets have G and IAS limitations and fatigue lives. I am not saying that this was the case with this Reaction but how had it been flown in the past ?

The problem is this: The fatigue of metal structures is an exact science and metal often shows signs of distress, before it fails at a predictable time, cycles etc., or stress level. Not so composites and this is one of the big problems with fullsize composites, often they show no signs of imminent failure they just fail without warning (according to an article I read in a semi professional aviation magazine, possibly Air and Space Smithsonian, or Flight International) so that is not a figment of my imagination. Things have probably improved over the last few years with the increasing use of composites in load bearing components of real jets. (Harrier, 787, A380 etc)

Same with composite models, they may look fine but eventually they fail unpredictably, push them too hard and you will expedite eventual failure.

What can be done if we cant predict the failures ?

Two things, resist the temptation to over power the airframes, and fly the model like a real jet, with care and consideration remembering that hard and aggressive flying will probably hasten the failure of even the best and strongest structure. It may not cause failure on that specific aggresive flight but it can and probably does add to the cumulative stress on the airframe which may possibly fail later, even though being flown "normally". Finally if an AD is issued, comply !

No doubt Kraivuth will respond but Reaction owners can be assured that they are flying a VERY well constructed ARF, but it is NOT a speed model. Put the LE tape on ALL reactions.

Finally it may be remembered that I redesigned the tail of my Reaction to make it all removeable, a design copied by the factory, I have thoroughly flight tested this mod (including crashing it !)absolutely no problems have been revealed.

Regards, David Gladwin.

TURBOMC

My Feedback: (7)

Thank you for the elaborative and insightful commentary David! I can tell you with absolutecertainty thatI cannottell when a composite structure starts to exhibit signs of fatigue.Maybe other modelers can. I agree with youthat somepeople do grossly overpower theirplanes and getaway with it for many flights (i.e.Kraivuth purposely trying to over stress the Reaction ARF to see if it will fail with a high powered turbine)but I don't think that this plane lands in that category witha mere 21 lbs ofthrust. You wondered how myparticular plane had been flown andIwould say the it was flown moderately agressive. Having said that the airframehad onlyfive 5 - 7 minutes flights on it.I will guarantee that if I do buy another Reaction ARF it will get tape on the leading edge. I wonder ifthe current productionReaction ARF build instructions state that tape needs to be applied tothe wing's leadingedges.

TURBOMC

My Feedback: (7)

Almost forgot aboutBobH's reply about seeing thewing's leading edgewithoutit being propped open.Here's apic of thesame wing portion without the prop. Note that Iapplied sometape to hold it closed in its original position..

LGM Graphix

My Feedback: (22)

TURBOMC,
Let me say thank you to you. You could have come on here with this issue and it been another thread like so many before, demanding that it is PST's fault and they OWE you a totally new airplane etc, but you have remained diplomatic and civil. That is tough to do when you suffer an airplane loss like this. The Reaction is a very good airplane. I think all manufactures have at some point had one of their products fail, it seems to be more and more often these days with the asian models, I hope that these threads teach people that when you are buying a low cost (comparitively speaking) that you should reinforce certain area's whether or not its' recommended. It's sad to think that a piece of tape (admittedly not something you SHOULD have had to do) could have prevented this crash.

kumpol

Hi Turbomc,

First of all  sorry for the lost of the Reaction but. It’s very difficult for PST team to rectify the problem from just a few pics. We would like you to grab both wing and have them sent to us for investigation. I can assure you that PST will stand100% behind their products. There about 400-500 Reaction out there and this is the second report that we have about wing failure and they mostly happen with over power and during high speed drives. We will do the best we can to help you out.Please send those wings to us  for investigation then we can take action.

KUMPOL

PSTJETS THAILAND

Sonicwings

PST Reaction...

The wings to go back to them for inspection, What i would expect they would want...

WELL DONE TO PST, For taking a look into this... TURBOMC, send them back to them, and let us know
in due course what comes out of it all... GOOD LUCK...

Jeremy.

BobH

My Feedback: (2)

Good for you for requesting the wings, I belive you have "manned up" to at least see whats going on..

There are engineering designs that can elimenate the problem. It would mean a slight change in your molds though. Were I you I would look at the cure time, application time of the wing joining.. I've delt with other Mfgs where their mastic started tp cure some before it was applied. The results were joint failures. Normally its a worker timing issue and not a fault of the mastic.

Turbomc the additional picture doesn't tell me alot except it appears as though no material left the wing before the separation. The only conclusion I can reach is that you have a catastrophic joint failure.

RCISFUN

My Feedback: (44)

Soooooooo

I have a Reaction ARF X that was manufactured October 2009.... should I be applying the LE Tape?
If so what are the specifications of the tape to be applied?

drdoom

My Feedback: (9)

I would,Better be safe than sorry..

highhorse

My Feedback: (2)

OK. Good for PST, I suppose. But something bothers me here. It could be a language barrier issue, but how can there have been only ONE failure prior to this and "THEY" happen "MOSTLY" in over-powered high speed diveS (plural)?? I'm no forensic linguist, but the man's command of English seems excellent. Better than some of my US brethren, for sure.

Also, I see this as bass-ackwards. PST should send the guy his kit along with an airbill for return of the wing at THEIR expense.

This is a KNOWN issue and not some head-scratching detective mystery. There is no need on the front end to doubt the man's word that the frigging thing blew up in flight. The pics are clear enough to reasonably assume that the man is telling the truth, so send him his new model already. If PST decides later that they have been lied to THEN they can come right back here and say so.

I don't see it as "manning up" on PST's part. More like "boying up".

To be fair, it's a better response than almost any other mfr would have given, but then again, our expectations have been so steadily eroded over the years that even "boying up" seems righteous !!

Gordon Mc

My Feedback: (11)

Good to see that PST is at least willing to check the wings out. Hopefully they offered to help with shipping, so that the OP is not even further out of pocket.

BTW, maybe I am misunderstanding what's being shown here, but why is it that the pictures seem to show a CLEAN bead of glue along the fracture point ?

Whenever I have broken open a composite structure, I have always seen little bits of balsa, ply, glass cloth, etc., etc embedded in any such glue beads - unless of course the bead missed its target and did not actually glue to anything. Where's the 'debris' that the glue ripped out of the mating surface when the wing came apart ?

Am I missing something here ?

Gordon

BobH

My Feedback: (2)

Read my last post.

TURBOMC

My Feedback: (7)

Thanks for the reply Kumpol! How do I go about sending the wings back to Thailand? The other wing is busted up but, whole so I'm going to needto put it in a large box. Do you have a UPS account or otther courier service account I could use? How aboutme sending it to Bruce TharpeEngineering instead. I wouldn't mindpaying for that freight. Also I need the shipping address. Thanks again for your inquiry!

sc0tt

My Feedback: (61)

For the record, Iam the guy who had the first wing failure resultingin the AD#3, dated June 2009.

It was serial #R0053.Power wasanoriginal Jetcat Titan turned down to 30#'s. (I already had the turbine, so that's why I used it). I also blocked off the open holes in the wheel well ribs, as I do on all my non-gear door jets. The aircraft was NEVERabusedor pushedlike some people do- no slamming the sticks, hard G-pulls, no full throttle diving passes & no hard landings. Due to airframe drag, the Reaction is not a speed machine and it isnot built to be abused.

Flight #38, on a 1/2 throttle pass over the field there was a loudpop.Theleft wing blew apart and the jet spiraled in. Below are post crash pics. Icutopen theother wing and you can see the lack of glue andno bonding to the skin in some areas. In my opinion, air got into the leading edge somewhere, pressurizing the wing resulting in it blowing apart at the weak glue seams. (just like some original CARF Eurosports)

Knowing this was a major quality & safety issue, Icalled Bruce at BTE and told him what happened. Idid not askfor anything, nor was I expecting anything.I wrote it off as a loss andthought forsure I would get blamed forusing a Titan, being forced to defend myself.I sentthe pics to Bruceand PST for evaluation. I was told that serial #100 and below were not built for larger turbines and that they would issue an AD. Then to my total surprise, they offereda freereplacement kit in my color choice. Within a couple weeks I had the new Reaction at my door. In fact, that replacement is pictured here... http://btemodels.com/rarf-allyellow.htmlBTE & PST's customer service went far beyond any ofmy experiences with BVM or CARF.

Having said this, Ido not feel PST should start handing out free kits to anyone who crashes. If it can be proven there was a major manufacturing defect like mine, then I leave that to them to do the right thing. However most issues can be handled by an AD -but owners do not always comply with them. Also, there are too many who's actionsa manufacturer cannot control. No offense, but this is a "cheap" kit & basically a trainer. Too many people push the limits and eventually it will bite you -just look at Dustin's latest event at Joe Nall.

More in my next post............Scott

sc0tt

My Feedback: (61)

Regarding later kit glue joints, myreplacement Reactionwas greatly improved. Not perfect, but definitely better than the first. Very hard to take pics, but looking in the wings with a flashlight Icould see the leading edge and ribs had a lot more glue on them. However, there were some spots I wanted to improve. To reach in the wingI put some 6mm fuel line on a hysol nozzle and injected as best I could.

Even though the AD implies s/n# 100 and lower, Istill taped my all the leading edges as a measure of confidence. Blocking off the holes in the wheel well is something I also highly suggest.
Off subject, but my other suggestion is a bigger rudder. I made mine 1" wider & it makes all the difference in knife edge, etc

Despite some growing pains and some easily resolved issues, I would stillrecommend the Reaction. I find it a nice relaxing flyer and good for grass and short fields. In fact I've upgraded to a Reaction X with P120se. Personally, I think the 120 is the perfect size for this airframe. Adequate vertical, but the airframe is draggy sodon't expect a lot of speed. Full throttle straight &level passeswill seem slow if you're used to bandit's, flashes, etc.

....Scott

Gordon Mc

My Feedback: (11)

I'm glad that PST stepped up and did right by you, but IMO, trying to pass this off as an issue to do with the size of the turbine seems to be pure marketing hype.

Given that the glue in the photos does not come in contact with the surface it is supposed to glue the undersized ribs to, I would say this is nothing to do with whether the aircraft was build for larger turbines or not - it was simply a poor manufacturing job - period. Even with a smaller turbine, what's the point of putting in structure and glue that doesn't actually glue anything to anything else ?

sc0tt

My Feedback: (61)

Yes, I agree with the turbine size being apoor excuse when it was obviously the build quality. I'm not sure if PST increased the rib size or just added more glue, but my last two have full rib to skin and leading edge contact. Stuff like this makes one appreciate BVM or CARF products more and understand the price difference.

kumpol

We did all the test with our prototype( pre production models,) it have had happen when we put big engine 36lbs or more just to abuse it for trying to break the model . We just want to know how tough she can take and we did it many times and we found the crack laterally along the rear spar, early model we didn’t not glass the rear spar after we found the problem we glass all of the rear spar on all the production models.

 

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Kumpol