Facts regarding "plastic" planes

[Rudix]

A few more points I missed in the other post:

Did the person doing the lamination manage to remove all air bubbles ?

Was the molding "baked" or molded using a vacuum process ?

Did the molding cure completely before it was removed from the mold ? If you flex a laminate to soon you will loose a lot of strenght due to micro delamination between fibres and substrate and due to the epoxy molecule chains getting stretched/broken !

A huge part of the problem is to monitor the manufacturing process and applying quality control is not easy, one of the reasons there are not that many ceritified "plastic" light planes in the US, in the US they are rather particular about safety unlike some eastblock countries !

I would be very carefull to use laminates for main load bearing structures, here metal and even wood still rules.

Just my 2c (plus lots of inflation !)
Rudi

[RudiGreyling]

Ditto RudiX,

that is why I'm building a blik, maybe in 10 years when there are more datapoints, more history, will I consider a plastic.

Plastic has many advantages, the early addopters are either going to be very happy, or very unhappy.

Rudi

[Rudix]

Ditto RudiX,

that is why I'm building a blik, maybe in 10 years when there are more datapoints, more history, will I consider a plastic.

Plastic has many advantages, the early addopters are either going to be very happy, or very unhappy.

Rudi

Hi Rudi,

Yes, time will tell ! I can show you some wings (F3B R/C glider) I moulded in 1979 and 1982, they were molded with the best Ciba-Gigy epoxy available using carbon and Kevlar fibre and were considered "state of art". They have been in storage for years and thus did not have that much UV exposure BUT they are totally unflyable today !

The epoxy have gone yellow and soft, even making bubbles and delaminating ! Glad it was not on a homebuild !

I am wondering about that KR2S that has been in storage since 1996 ?

BTW, love your RV and the updates you are giving us ! I think as soon as my Pietenpol is flying a RV would make a great next project


Safe flying,
Rudi

[Boet]

Hierdie nuwe plastiek errouplyns laat my bietjie kop-krap en vrae vra. How old is the oldest plastic aeroplane?? Not exactly time tested and proven, are they? With how much "dignity" will the, for example, Sting, age? My rag and tube and wood Turbi 2 is 25 years old. One of these days I will need to take a knife and cut the fabric off, give attention to everything inside, cover it with a "New Turbi", and off I go for the next 25 years. I will then be 78. Damn, my aerie will probably out live me.
Catch my drift??

[Rudix]

Hierdie nuwe plastiek errouplyns laat my bietjie kop-krap en vrae vra. How old is the oldest plastic aeroplane?? Not exactly time tested and proven, are they? With how much "dignity" will the, for example, Sting, age? My rag and tube and wood Turbi 2 is 25 years old. One of these days I will need to take a knife and cut the fabric off, give attention to everything inside, cover it with a "New Turbi", and off I go for the next 25 years. I will then be 78. Damn, my aerie will probably out live me.
Catch my drift??

Hello Boet !

Ja, ek stem, ek het die afgelope 25 jaar of so hope goed gebou uit "plastiek", model vliegtue, drones, resies kar parte, KR1/KR2S ens en ek is baie vertroud met die proses maar ek moet erken ek het te veel gesien om die lot te vertrou. Ek is heeltemal gelukkig om 'n cowl of spat daarvan te bou maar nie trukturele dele nie !

Ek reken my Pietenpol het ook 'n baie goeie kans om my te oorleef

Die gedagte om 1/2m te spandeer op iets wat dalk nie 5-10 jaar sal hou is vir my heeltemal onaanvaarbaar, en dan praat ons nie eers van herstel werk nie !

Groete daar in die woestyn
Rudi

[emil]

[quote="Rudix
Well, I have decided that I WILL visit the factory next week when I am in the region anyway and I am going to try and clear this lot up. If they can convince me that the life of the Sting airframe is the same as other composites I will be very interested in getting one to use for commuting. Normally airframe lifetimes for composite planes are quoted in the 10000 h plus region.


Safe flying,
Rudi[/quote]

soos ek weer se as jy se "composite planes are quoted in the 10000 h plus region" dan kry ek die ouens jammer van die A380 en die rooi valk.... en nog verder op die ander post se jy die price tag is tehoog en hier se jy .."I will be very interested in getting one to use for commuting"

mmmmmmmmmmmmmmmmmm

[The Agent]

Bliksem but you okes can like to shoot a man's plane down and you have not even been in it, The Sting is an awsome piece of flying marvel and modern at that give it time to prove it.

Rudi no disrepect it took you almost 6 weeks to get your plane up here from PM .

We just jumped in and brought the Sting back one shot bru but we did not shoot you down for the problems you had.

Live and let live.

Morph I know the Bantam si is fugly but its mine it picks me off the groung and I have the greatest respect for it, you and I will have some beers soon then we can laugh about all of this.

[Rudix]

Bliksem but you okes can like to shoot a man's plane down and you have not even been in it, The Sting is an awsome piece of flying marvel and modern at that give it time to prove it.

Rudi no disrepect it took you almost 6 weeks to get your plane up here from PM .

We just jumped in and brought the Sting back one shot bru but we did not shoot you down for the problems you had.

Live and let live.

Morph I know the Bantam si is fugly but its mine it picks me off the groung and I have the greatest respect for it, you and I will have some beers soon then we can laugh about all of this.

Agent I did not say the plane is BAD, please guys, READ !!!

What I said, and what I am still saying along with 1000's of people worldwide is the composite construction has limitations, one being expected airframe life !!

So, now tell me, where does this "6 week" story come from ? The structure of the plane had ziltsh to do with that ! And remember all the crappy comments by your buddy ?

Does the time it took me to find a weather window to move a plane have ANYTHING to do with my knowledge of airframes or composite structures ? I think NOT ! I still believe I am better qualified (yes, papers on the wall !) than most to make a judgement on airframes because I talk from a point of knowledege gained by years of studying and not because I have fallen in love with a plane !!! And again, I am not the only person on the planet with concerns like this, even the FAA in the USA have their doughts ! Some companies like Piaggio have moved back to metal construction on many components because of these issues !

It is not only the Sting that is effected by this, I see some sources quote the Lancair airframe life as "The Lancair Columbia 300 has an airframe life limitation of 1200 hours. " !! WOW

Here is the link were I quoted from :

http://www.meyersaircraft.com/Common/Al ... ction.html

Here is the link to the USA version of the Sting manual, check point 7.1 !

http://www.mcp.com.au/gosportpilot/info ... %20USA.doc

I think it is very important not to go through life blinded by sales talk without looking for facts, just because a plane looks nice and flies superb does NOT mean it will last long !!!

So, please do not comment on things that you do not understand !!

Safe flying,
Rudi

PS, I took the "Sting" out of the original subject to try and take the "Sting" out for some guys and so that it does not appear that I have an action against a particular aircraft or person/s !

[Morph]

I agree. I also understand that the composite planes dont take heat well. Someone said this is why you can only get them in white.

Another thing I was talking to someone this weekend about Jabiru's and we were discussing cracks developing in the fibreglass. He was telling me you can't see them but when you taxi down a rough runway you can hear the airframe creaking and cracking.

Personally I prefer lap en pype, the thought of a composite wing seperating in flight scares the absolute crap out of me.

[RV4ker (RIP)]

Guys it all speculation. No one knows the answers, that why the big debate... Similar argument to engine TBO's. In rest of world it all about liability. If you prang who pays. Some of the aerobatic types being built using composites are stessed to +/-20G's.

Only time will tell and until then everyone will be an expert and none will agree...

2c

[janvdm]

Hi Rudix,

I will be visiting Urbanair (Samba factory) as well as the Sting factory on the 25th and 26th October 2006 in the Czech Republic. On your return from your visit please post some interesting do's and don't that you experienced on your visit and or if you need addisional info that I can gather, please shout.

Regards

Jan van der Merwe

[emil]

Rudi maybe you should post a warning to Glenn Dell as well cause the Slick 360 all the new Extra model the edge 540 ..name it is not BLIK aeries any more but compasite.....please dont tell me these guys will move away from BLIK to compasite if it is weaker in any way...the Extra and slick i know they fly + and _ 10 G's........

[Sting and Dynaero]

Guys I think first and foremost one must understand that most of these manuals are translated and then it does not say that it has a life of 1000 hours. It says that after 1000 hours it must be inspected. I think that is a good idea. And the Sting is made out of Carbon Fibre which is now more and more being used by commercial aircraft and as a fact is more durable than the old blik aeries.

So Rudi I have many many hours on various Stings and I have flown our four seater Dynaero, which is also Carbon Fibre, from France through Africa to South Africa in some interesting weather. These planes are strong and very durable, but obviously it is prudent to advice owners to stay within the operating parameters.

I will be glad to answer any of your questions

[emil]

now this is strange...Mr Rudi that cant say one good thing about our "plastic" aeries arrived yesterday at Rhino Park in a JAB wiht H2000 on the clock..... mmmmmmmmmm

now this is wierd....

[Rudix]

Ok, let me summerize a few basic principals;

1) The problem with Composite planes are NOT the Carbon or glass, it is the EPOXY that is used in the laminate.

2) Not all epoxies are created equal or have the same ageing character.

3) A language point: FUSS = fuselage, that is only the bit you sit in and and is attached to the wing/tail, The other bits (wing and tail) are the ones that tend to be the problem with life since they are under a lot of stress while flying.

4) Not all composite planes use the same epoxy or for that matter the same curing process or thickness of laminates, thus, their airframe lives can be different !

5) Strength does not always equate long life ! IT IS NOT THE SAME THING ! A laminate can be as strong as hell, that is till the epoxy starts getting soft/brittle due to age !

6) I have made this point before but let me say it again: I AM NOT SAYING ALL "PLASTIC" PLANES ARE BAD !! There are some great ones out there, like the Jabiru with a KNOWN LONG AIRFRAME LIFE !! BUT, on some there are unknowns, and if even the manufactured won't put his C on the B that the airframe won't last more than lets say 1000h's I think it is not unreasonable of me (and many others) to be carefull.

Ok, I hope the above makes sense to someone

Happy flying,
Rudi