Facts regarding "plastic" planes

[Rudix]

This is what I love about flying, there is just so much passion

Now that we have excluded the Sting from the conversation, we are down to 489 other choices. Who wants to shoot down the next model . We will eventually get there by elimination

I think the next one should be the Streak Shadow for it's risk of prop strikes. Rudix, you should know Emil has just bought a Sting. Don't down a guy's aerie, unless of course it is as ugly as the bantam Agent flies

Hi Morph !

Ok, before we shoot down the next model.......

Here is an extract from the OFFICIAL Sting owners manual (US version), the bit about airframe life ! Look at the paragraph in bold If anyone wants to look at the complete manual I have a copy.

Quote:

7.1. Service life of the plane and its parts

There are three major components which determine the life of the aircraft:

* Airframe
* Engine
* Propeller

The service life of the airframe will depend on the stresses experienced during its lifetime. Avoid high stress maneuvers and rough turbulence where possible. Do not disassemble the aircraft needlessly and only anchor the aircraft in accordance with the manufacturer’s instructions.

Whenever possible, hangar the aircraft to avoid damage by the sun, dust and wind. If hangarage is not available, cover the aircraft if possible. Regular polishing with high quality car polishes will aide in maintaining the airframe.

Initial airframe service life is set at 1000 hours or 5 years, at which time it should be reviewed by the manufacturer and adjusted accordingly.

The propeller should undergo regular inspections as set out by the manufacturer. To prolong the life of the propeller, avoid long grass and stone areas which may damage the leading edge.

There is no specified service life of the engine. The engine is subject to review by the manufacturer after every 1200 hours.

End Quote:

So, I did not suck the 1000 hour thing out of my thumb, I did some research on the Sting a while ago !

I rest my case..........

Prop strikes on the Shadow ? :D No problem with the Jabiru engine and a 3 blade prop, can start the engine with the plane resting on it's tail. :D

Ok, down to the real question !

Right now the Skyranger looks like the best option, will visit the factory soon !

Safe and peacefull flying everyone !
Rudi

[Morph]

Where have you been. Him and Agent flew it back from Cape Town last week sometime. Hang on, maybe Agent bought it or both

[Rudix]

Where have you been. Him and Agent flew it back from Cape Town last week sometime. Hang on, maybe Agent bought it or both

[RV4ker (RIP)]

Morph
Think that one is destined for Piet Retief (town, not the dude). Emil possibly going to get his next.... I am hoping to do convex and will post a "review" of the aerie. Something like a Pleb Pilots Perspective..

[Rudix]

Morph
Think that one is destined for Piet Retief (town, not the dude). Emil possibly going to get his next.... I am hoping to do convex and will post a "review" of the aerie. Something like a Pleb Pilots Perspective..

Hi RV (Hey, those are my initials !)

That would be very interesting, I would love to hear what you think of the Sting ! Looking forward to reading your "review". From what I have read it is a real performer, just the 1000 hour thing and the price that puts me of a bit but the price is all relative as it looks like it is a lot of bang for your buck.

Rudi

[emil]

This is what I love about flying, there is just so much passion

Now that we have excluded the Sting from the conversation, we are down to 489 other choices. Who wants to shoot down the next model . We will eventually get there by elimination

I think the next one should be the Streak Shadow for it's risk of prop strikes. Rudix, you should know Emil has just bought a Sting. Don't down a guy's aerie, unless of course it is as ugly as the bantam Agent flies

Hi Morph !

Ok, before we shoot down the next model.......

Here is an extract from the OFFICIAL Sting owners manual (US version), the bit about airframe life ! Look at the paragraph in bold If anyone wants to look at the complete manual I have a copy.

Quote:

7.1. Service life of the plane and its parts

There are three major components which determine the life of the aircraft:

* Airframe
* Engine
* Propeller

The service life of the airframe will depend on the stresses experienced during its lifetime. Avoid high stress maneuvers and rough turbulence where possible. Do not disassemble the aircraft needlessly and only anchor the aircraft in accordance with the manufacturer’s instructions.

Whenever possible, hangar the aircraft to avoid damage by the sun, dust and wind. If hangarage is not available, cover the aircraft if possible. Regular polishing with high quality car polishes will aide in maintaining the airframe.

Initial airframe service life is set at 1000 hours or 5 years, at which time it should be reviewed by the manufacturer and adjusted accordingly.

The propeller should undergo regular inspections as set out by the manufacturer. To prolong the life of the propeller, avoid long grass and stone areas which may damage the leading edge.

There is no specified service life of the engine. The engine is subject to review by the manufacturer after every 1200 hours.

End Quote:

So, I did not suck the 1000 hour thing out of my thumb, I did some research on the Sting a while ago !

I rest my case..........

Prop strikes on the Shadow ? :D No problem with the Jabiru engine and a 3 blade prop, can start the engine with the plane resting on it's tail. :D

Ok, down to the real question !

Right now the Skyranger looks like the best option, will visit the factory soon !

Safe and peacefull flying everyone !
Rudi

now this is funny

you can download the manual from
http://www.tl-ultralight.cz/download.php

and the index is

7. Service life of the flight and maintenance periodicity 36
7.1. Service life of the plane and its parts 36
3
7.2. Workaday maintenance 36
7.2.1. Lubricant plan and lubricant preparation 37
7.2.2. Blocking, raising and jogging along preparation 37
7.2.3. Disassembly of front wheel 38
7.2.4. Wheel disassembly of main undercarriage 38
7.2.5. Mending the tyre 38
7.2.6. Electrical system voltage 39
7.2.7. Tolerance and setting up values 39
7.2.8. Supporting and subordinate construction 39
7.2.9. Special assembly, controlling and setting preparations 39
7.2.10. Special tools 39
7.2.11. Materials for small reparations 39
7.2.12. Changing the fuel filter in the engine area 39
7.2.13.Maintenance of airscrew SR 2000 xa 40
7.3. Contract revision 41
7.4. Periodical revision after every 50hours 41
7.5. Periodical revision after every 100hours 41
7.6. Periodical revision after every 200hours 41
7.7. Periodical revision after every 300hours 41
7.8. Jacking points on the plane 42
7.9. List of labels and their placing 42


and then 7.1 is

7.1.Service life of the plane and its parts
The service life as one part consist of the service life of decisive parts which are the airframe,
engine and the airscrew. Wear of the airplane depends on its stress and that’s why you should
keep away from high stress on the construction, especially by high flight multiples. Do not
disassembly the airplane needlessly and anchore the airplane only introduced way. Also keep
away from landing in high lawn, which can expressively take the trouble on the airscrew.
Regular conservation with high quality car vosk expressively terminates aging of the varnish.
Park the airplane in covered hangar if possible, at least, protect the airplane against unfavorable
influence by covering.
There is no service life of the engine. The engine is subject to revision after every 1200 hours in
a service center, where is the service life specified.
The service life of the airscrew is not set, it undergoes regular revisions at the producer. The
service life will be specified due to its factual state.



NOTHING ABOUT THE HOUR OR YEARLY LIFE of the FUSS

FUNNY

[Morph]

What bothers me with the Sting is the short life expectancy of the airframe, as low at 1000 h according to some sources

Initial airframe service life is set at 1000 hours or 5 years, at which time it should be reviewed by the manufacturer and adjusted accordingly.

Rudix are we talking about the same thing here. I read that the airframe requres servicing and checking at 1000 hours and therefter at intervals as set by the manufacturer, not that the entire lifespan of the airframe is limited to 1000 hours and after that it is about to fall apart.

Hell I don't believe there are any microlights in the world that can go over 1000 hours and not have the airframe serviced, even the lap-en-pyp types. My Challenger of which there are almost 4000 made, some of whom have exceeded 3000 hours still need to have the airframe serviced every 500 to 1000 hours, depending on component.

[Rudix]

What bothers me with the Sting is the short life expectancy of the airframe, as low at 1000 h according to some sources

Initial airframe service life is set at 1000 hours or 5 years, at which time it should be reviewed by the manufacturer and adjusted accordingly.

Rudix are we talking about the same thing here. I read that the airframe requres servicing and checking at 1000 hours and therefter at intervals as set by the manufacturer, not that the entire lifespan of the airframe is limited to 1000 hours and after that it is about to fall apart.

Hell I don't believe there are no microlights in the world that can go over 1000 hours and not have the airframe serviced, even the lap-en-pyp types. My Challenger of which there are almost 4000 made, some of whom have exceeded 3000 hours still need to have the airframe serviced every 500 to 1000 hours, depending on component.

Ok, first of all, there are more than one version of the manual out there, looks like the US vesion (the one I quote as I stressed in my original post, expecting this to become a bone of contention !) contains more specific detail, as required by the more stringent US laws.

The consensus seems to be that till the airframes reach 1000 h they won't confirm the lifespan, when you get to 1000h the plane must be inspected (by the factory?) and then they will advice. The way they have it in the manual, and as discussed by the US forums, they might tell you after 1000h that your plane is at the end of its life. Remember it is very difficult, if not impossible, the "service" a moulded airframe the way you van service a "lap en pyp" or rivited metal or wood airframe. It is a known fact that epoxies (not the carbon/glass fibre) does have a limited life and is very adversely affected by heat, UV and some chemicals. There are 1000's of different epoxy formulations, some a lot better than others......

There has been a huge amount of discussion on this on the web, this is nothing new. Right now the discussion is very devided, why does only the US version have this in the manual ? Is it because it is build differently (NOT likely!) or because they are scared that they will be nailed in the US if a plane suffers structural failure ?

Here is a link to the US version of the manual:

http://64.233.183.104/search?q=cache:uk ... =clnk&cd=8

Anyway, this is all a storm in a teacup as far as I am concerned since I do not own a Sting and I am not planning on owning one unless this is cleared out completely!

Rudi

[Morph]

Have you read that manual, lots or Czech-English, now called Chinglish

"The saving system is constructed for the maximum speed of flight 240km/h, so if such situation happens, which responds to using the saving system, arbitrate quickly."

"Vibrations can exhibit by the glide performing and this is the consequence of unsymetric by-passing the aerodynamic clean airplane TL 2000 Sting Carbon. In this case slow down the speed of the glide."

How can you quote anything from there

I believe the bigger question here is have there been airframe related failures in Sting products that have resulted in crashes or near crashes over the last few years.

[Morph]

Prop strikes on the Shadow ? :D No problem with the Jabiru engine and a 3 blade prop, can start the engine with the plane resting on it's tail. :D

I was refering to the bush suitability of the plane. You would have a problem landing on rough runways and paths expecially if they are very stony and/or have a hump in the middle. The Shadows should stick to nice clean runways if possible.

[Rudix]

Have you read that manual, lots or Czech-English, now called Chinglish

"The saving system is constructed for the maximum speed of flight 240km/h, so if such situation happens, which responds to using the saving system, arbitrate quickly."

"Vibrations can exhibit by the glide performing and this is the consequence of unsymetric by-passing the aerodynamic clean airplane TL 2000 Sting Carbon. In this case slow down the speed of the glide."

How can you quote anything from there

I believe the bigger question here is have there been airframe related failures in Sting products that have resulted in crashes or near crashes over the last few years.

:D :D Yes, I have read it and it is rather confusing !

I did not "discover" this "problem", there was a huge story on one of the US forums and it got quite ugly !

The line "Initial airframe service life is set at 1000 hours or 5 years, at which time it should be reviewed by the manufacturer and adjusted accordingly." was what caused all the problems and to date it has not been cleared up by the factory, only removed from some later manuals, I am sure it did not do sales ANY good for them ! The reasoning was, from the people concerned, what if after 1000h the factory tells you the airframe is time-ex ?

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 100000 h plus region.

Yes, it would be interesting to know how many hours the oldest airframes have and if there has been any problems.

Safe flying,
Rudi

[Rudix]

Prop strikes on the Shadow ? :D No problem with the Jabiru engine and a 3 blade prop, can start the engine with the plane resting on it's tail. :D

I was refering to the bush suitability of the plane. You would have a problem landing on rough runways and paths expecially if they are very stony and/or have a hump in the middle. The Shadows should stick to nice clean runways if possible.

Yes, I agree, the runway at Petit is about as rough as I would like to fly the Shadow from, one of the reasons ZU-AVB is getting a new, Carbon fibre :D blade landing gear that will give it a lot more prop clearance and strength. Hmmm, I wonder what the life of the carbon blade would be, 1000h ? Hey, with the way I land I am sure it will be a lot less

Rudi

[Morph]

You probably find they wrote that manual very early, prior to them having any history on the airframe. So to be careful they tasked Boris to write the sentence as is . In the meantime they have sold in excess of 400 units and I am confident by now they have found the structural faults and found ways to fix them

Case in point, the Jora, newer model. The first two I saw here developed cracks in their undercarraige which was fixed in later models

[Rudix]

I think a big part of the problem here is the still unknown lifespan of molded airframes. The blik vs plastic discussion has been going for a while. Molded modern structures have many advantages BUT quite a few disadvantages as well.

With a metal plane you can calculate the ultimate strenght quite easy since you are working with known materials, with laminates it is a different story, it is almost impossible to take al factors into account like:

How old was the epoxy before it was mixed, most epoxies have a limited shelf life. And what is the chemical composition ? Is it suitable for the fibres used in the laminate ?

Was the epoxy mixed in the correct proportion (weight vs volume ?), this is rather critical ! And was it mixed well ?

At what temp was the epoxy mixed and used ?

Any contamination in the mix ? Like solvents from cleaning the tools ?

Were the fibres (glass/boron/carbon/kevlar or other exotic) prepared correctly ? Were there any chemicals left from the manufacturing process ?

Were the fibres "wetted" correctly ? And were the wetted correctly before the pot-life of the epoxy mix were beyond the optimum point ?

Is the ratio of fibre to epoxy correct and even througout the molding ? This is not easy to achieve !

Is the airframe UV protected correctly and how much exposure will it get ?

The list goes on, I have spend many years studying this and there are more questions than answers. The fact is that modern "plastic" commercial planes like the Airbus are designed to be "disposable" with a limited life, unlike the older planes. Where does this leave us ? Who knows.....


Ok, let me get of the soap box and stop lecturing (Yes, I used to lecture on this !)

Rudi

[Rudix]

You probably find they wrote that manual very early, prior to them having any history on the airframe. So to be careful they tasked Boris to write the sentence as is . In the meantime they have sold in excess of 400 units and I am confident by now they have found the structural faults and found ways to fix them

Case in point, the Jora, newer model. The first two I saw here developed cracks in their undercarraige which was fixed in later models

Yes, it is quite possible that they revised the lifetime as the fleet hours went up. Like the Jabiru 2200 engine, the TBO has been going up for a while.

The fact that cracks developed in the undercarraige scares the cr@p out of me ! On the uc it is fine since it is easy to see but what about the wing spars or the joint between the spars and skins (maybe the spars are not molded ?) ?

The fact that the uc cracked tells me they did not do their homework well and got the epoxy tipe/ratios/strength of laminate wrong ! If it happened on the uc it can easely happen somewhere else in the airframe. Have you looked at the spars in those planes ? Yes, I know, impossible in most cases without destroying the wing ! I would not feel safe flying in a plane like that if I know there was a problem already.....

You see, this is a very difficult and sensitive subject....

Rudi