Typical glider service lives?

[[email protected]]

I noticed the SZD-55 has a service life of only 3,000 hrs with a possible 1,500 hr extension. Is this typical of other modern ships like the Discus, Ventus, LS, DG series etc??

[[email protected]]

I think it’s pretty typical. My ASW-15 just completed it’s 3,000 hour inspection and is good until 6,000 hours. Given my typical utilization (50 hours a year if i’m Lucky) it’s unlikely to need another life extension inspection during my lifetime.

[Ross[_3_]]

There are a couple of Janus flying round in France somewhere that as far as I am aware are allowed to go to 18,000 hours. 12,000 hour check done, extended for another 6,000. Not bad value for money if you intend on flying a lot :)

[[email protected]]

Do Schempp-Hirth and Schleicher published approved service life numbers somewhere on their websites? I can’t find them.

[Dan Daly[_2_]]

On Thursday, November 22, 2018 at 1:21:08 PM UTC-5, wrote:
> I noticed the SZD-55 has a service life of only 3,000 hrs with a possible 1,500 hr extension. Is this typical of other modern ships like the Discus, Ventus, LS, DG series etc??


Not accurate information. Service Bulletin BE-012/55-1/2012 extends the service life of the SZD-55-1 to 12,000 hours (from 3,000). It requires periodic inspections every 1,500 hours with the results sent to the Type Certificate Holder (TCH) who responds with a life extension for the next 1,500 hours, up to 12,000 hours), some FM and TSM pages changes.

In the preamble, in part:
"To extend the life-limit of an airframe of SZD-55-1 / SZD-55-1XM the Allstar PZL Glider (TCH) has completed the actions as follows:
- precise check of four gliders S/N 551193056, 551190005, 551191010
& 551192042, respectively after 2908, 3341, 2978 & 2963 FH TT (total time);
- fatigue characteristic of SZD-55-1 airframe structure;
- fatigue test of wing connection’s node."

A copy of the SB is on the SZD-55 Yahoo group, which I moderate.

Dan
2D (551190001 - still a baby at 1,006 hrs)

[[email protected]]

Well then!! Thanks Dan!!

[Dave Springford]

Schempp-Hirth gliders have a 6000 hr limit before the first inspection, and if IRRC, all Schleicher gliders have a 3000 hr limit before the first inspection.

They can typically be extended out to 12,000 or 18,000 hours with recurring inspections.

However, since most privately-owned gliders tend to fly 100-200 hours per year a 12,000 hour life gives a 60-120 year period. Even a club or commercial glider that flies 500 hours a year still gets 24 years.

Big picture, life limits are not a problem for most gliders or owners.

[krasw]

FRP structure has no practical service life. Manufacturers approve more hours as fleet ages, at least those who are still in business. There is no reason to ground glider at 12/18000 hours, same inspection program always gives you another 1500/3000/6000 hrs.

[Nick Hill[_3_]]

On 22/11/2018 18:21, wrote:
> I noticed the SZD-55 has a service life of only 3,000 hrs with a possible 1,500 hr extension. Is this typical of other modern ships like the Discus, Ventus, LS, DG series etc??
>

Most new glider designs come to market with an initial service life,
which currenty seem to be 3000 or 6000Hrs. When some examples reach that
initial limit the manufacturer (assuming they still exist) then define
an inspection program to be undertaken which allows the life to be
extended be say 6000Hrs. The process repeats when one gets to 6000Hrs etc.

If you look in the TN/ADs from the various maufactureres you will find
technical notes being issued defining extensions.

Example the LS4 originally had a service life of 3000Hrs. TN4027a for
the LS4 now details the inspection program as at 3000, 6000, 9000, 10000
and 11000 which allows a service life up to 12000Hrs.

DG and Schleicher still seem to start with 3000Hrs as did earlier
Schempp Hirth gliders. Later Schempp gliders have 6000Hrs as the initial
life.

The SZD-55 is probably an example that the life was initially 3000Hrs
after which SZD produced an extension up to 4500Hrs. The original SZD
manufacturer didn't really exist for a while so nothing further
happened. The newer Allstar PZL company which now owns the design and
manufactures the glider produced a TN to extend the life upto 12000 hrs
in 2012

Nick

--

Nick Hill

[Alan Garside]

Check out the service life of the Pik20D's

https://www.trafi.fi/filebank/a/1475753853/f16de445be2565d9ba75dc5391142167/22742-PIK-20D_Fatigue_evaluation_20151115.pdf


which is referenced in the EASA SAS for the Pik20D after the guy's in
Finland had the Pik20D recertified as fully aerobatic in 1999.

The report was requested by EASA so they then had to accept it

Some info from the report.

"- 10000 FLH aerobatic flight only
- 65000 FLH total flight time including max 8000 FLH aerobatics
- 265000 FLH without any aerobatics"

"For reaching a long time usage of the glider, say 65000 FLH which could
take over 500 years with an annual flight time of 100 FLH"

"it is proposed that for a normal condition aircraft the fatigue
inspections are started at 10000 FLH with an interval of 5000 FLH until
65000 FLH is reached."

The report sates these are fatigue inspections not life inspections. The
report makes interesting reading for it's implications for all composite
gliders.


At 10:10 23 November 2018, Nick Hill wrote:
>On 22/11/2018 18:21, wrote:
>> I noticed the SZD-55 has a service life of only 3,000 hrs with a
possible
>1,500 hr extension. Is this typical of other modern ships like the
Discus,
>Ventus, LS, DG series etc??
>>
>
>Most new glider designs come to market with an initial service life,
>which currenty seem to be 3000 or 6000Hrs. When some examples reach that
>initial limit the manufacturer (assuming they still exist) then define
>an inspection program to be undertaken which allows the life to be
>extended be say 6000Hrs. The process repeats when one gets to 6000Hrs
etc.
>
>If you look in the TN/ADs from the various maufactureres you will find
>technical notes being issued defining extensions.
>
>Example the LS4 originally had a service life of 3000Hrs. TN4027a for
>the LS4 now details the inspection program as at 3000, 6000, 9000, 10000
>and 11000 which allows a service life up to 12000Hrs.
>
>DG and Schleicher still seem to start with 3000Hrs as did earlier
>Schempp Hirth gliders. Later Schempp gliders have 6000Hrs as the initial
>life.
>
>The SZD-55 is probably an example that the life was initially 3000Hrs
>after which SZD produced an extension up to 4500Hrs. The original SZD
>manufacturer didn't really exist for a while so nothing further
>happened. The newer Allstar PZL company which now owns the design and
>manufactures the glider produced a TN to extend the life upto 12000 hrs
>in 2012
>
>Nick
>
>--
>
>Nick Hill
>

[Alan Garside]

x

At 10:10 23 November 2018, Nick Hill wrote:
>On 22/11/2018 18:21, wrote:
>> I noticed the SZD-55 has a service life of only 3,000 hrs with a
possible
>1,500 hr extension. Is this typical of other modern ships like the
Discus,
>Ventus, LS, DG series etc??
>>
>
>Most new glider designs come to market with an initial service life,
>which currenty seem to be 3000 or 6000Hrs. When some examples reach that
>initial limit the manufacturer (assuming they still exist) then define
>an inspection program to be undertaken which allows the life to be
>extended be say 6000Hrs. The process repeats when one gets to 6000Hrs
etc.
>
>If you look in the TN/ADs from the various maufactureres you will find
>technical notes being issued defining extensions.
>
>Example the LS4 originally had a service life of 3000Hrs. TN4027a for
>the LS4 now details the inspection program as at 3000, 6000, 9000, 10000
>and 11000 which allows a service life up to 12000Hrs.
>
>DG and Schleicher still seem to start with 3000Hrs as did earlier
>Schempp Hirth gliders. Later Schempp gliders have 6000Hrs as the initial
>life.
>
>The SZD-55 is probably an example that the life was initially 3000Hrs
>after which SZD produced an extension up to 4500Hrs. The original SZD
>manufacturer didn't really exist for a while so nothing further
>happened. The newer Allstar PZL company which now owns the design and
>manufactures the glider produced a TN to extend the life upto 12000 hrs
>in 2012
>
>Nick
>
>--
>
>Nick Hill
>

[Tango Whisky]

While I'm (and not only me) pretty confident that fatigue of the composite structure is not a limiting factor for service life, I think that other components (pushrods, bearings, bellcranks etc) should be checked after a couple of thousands hours - especially when they are installed hidden from view and/or inacessibly.

[Boise Pilot]

The three Blanik L-13's that just returned to service after having the world fleet grounding AD repaired now have 6,000 hour service life.
Boise Pilot







On Friday, November 23, 2018 at 4:45:06 AM UTC-7, Alan Garside wrote:
> Check out the service life of the Pik20D's
>
> https://www.trafi.fi/filebank/a/1475753853/f16de445be2565d9ba75dc5391142167/22742-PIK-20D_Fatigue_evaluation_20151115.pdf
>
>
> which is referenced in the EASA SAS for the Pik20D after the guy's in
> Finland had the Pik20D recertified as fully aerobatic in 1999.
>
> The report was requested by EASA so they then had to accept it
>
> Some info from the report.
>
> "- 10000 FLH aerobatic flight only
> - 65000 FLH total flight time including max 8000 FLH aerobatics
> - 265000 FLH without any aerobatics"
>
> "For reaching a long time usage of the glider, say 65000 FLH which could
> take over 500 years with an annual flight time of 100 FLH"
>
> "it is proposed that for a normal condition aircraft the fatigue
> inspections are started at 10000 FLH with an interval of 5000 FLH until
> 65000 FLH is reached."
>
> The report sates these are fatigue inspections not life inspections. The
> report makes interesting reading for it's implications for all composite
> gliders.
>
>
> At 10:10 23 November 2018, Nick Hill wrote:
> >On 22/11/2018 18:21, wrote:
> >> I noticed the SZD-55 has a service life of only 3,000 hrs with a
> possible
> >1,500 hr extension. Is this typical of other modern ships like the
> Discus,
> >Ventus, LS, DG series etc??
> >>
> >
> >Most new glider designs come to market with an initial service life,
> >which currenty seem to be 3000 or 6000Hrs. When some examples reach that
> >initial limit the manufacturer (assuming they still exist) then define
> >an inspection program to be undertaken which allows the life to be
> >extended be say 6000Hrs. The process repeats when one gets to 6000Hrs
> etc.
> >
> >If you look in the TN/ADs from the various maufactureres you will find
> >technical notes being issued defining extensions.
> >
> >Example the LS4 originally had a service life of 3000Hrs. TN4027a for
> >the LS4 now details the inspection program as at 3000, 6000, 9000, 10000
> >and 11000 which allows a service life up to 12000Hrs.
> >
> >DG and Schleicher still seem to start with 3000Hrs as did earlier
> >Schempp Hirth gliders. Later Schempp gliders have 6000Hrs as the initial
> >life.
> >
> >The SZD-55 is probably an example that the life was initially 3000Hrs
> >after which SZD produced an extension up to 4500Hrs. The original SZD
> >manufacturer didn't really exist for a while so nothing further
> >happened. The newer Allstar PZL company which now owns the design and
> >manufactures the glider produced a TN to extend the life upto 12000 hrs
> >in 2012
> >
> >Nick
> >
> >--
> >
> >Nick Hill
> >

[[email protected]]

There's a difference between what is technically possible and what is legally allowed. There's an interesting read in the "Schleicher-book": before the 18,000h lifetime extension on the ASK21 was approved, a wing was tested in a fatigue evaluation program. This program received public funding by the German government. The intention was to get approval for 24,000h, but the program was running out of funds before that was accomplished. So far, the ASK21 is the only German FRP-glider with 18,000h service life.

[krasw]

lauantai 24. marraskuuta 2018 13.22.29 UTC+2 kirjoitti:
> There's a difference between what is technically possible and what is legally allowed. There's an interesting read in the "Schleicher-book": before the 18,000h lifetime extension on the ASK21 was approved, a wing was tested in a fatigue evaluation program. This program received public funding by the German government. The intention was to get approval for 24,000h, but the program was running out of funds before that was accomplished. So far, the ASK21 is the only German FRP-glider with 18,000h service life.

I guess german authorities are still holding their collective breath because FRP structures are so new thing that no one really knows how they behave. Just 60 years in service, it can disintegrate any minute without warning.

[[email protected]]

It's not a German authority approving life time extensions of airplanes anymore.

[Bruce Hoult]

On Saturday, November 24, 2018 at 3:22:29 AM UTC-8, wrote:
> There's a difference between what is technically possible and what is legally allowed. There's an interesting read in the "Schleicher-book": before the 18,000h lifetime extension on the ASK21 was approved, a wing was tested in a fatigue evaluation program. This program received public funding by the German government. The intention was to get approval for 24,000h, but the program was running out of funds before that was accomplished. So far, the ASK21 is the only German FRP-glider with 18,000h service life.

This is quite old now, but still good work

http://journals.sfu.ca/ts/index.php/ts/article/viewFile/708/666

[Eric Munk]

At 19:58 22 November 2018, Ross wrote:
>There are a couple of Janus flying round in France somewhere
that as far as
>I am aware are allowed to go to 18,000 hours. 12,000 hour
check done,
>extended for another 6,000. Not bad value for money if you
intend on flying
>a lot :)

As far as the tc-holder is concerned the max is 12000 hours for
any Schempp-Hirth glider. I would say you have the 18000
confused with the ASK-21 which is the only German built GFRP
glider certified for more than 12000 hours currently.

[Eric Munk]

At 00:09 23 November 2018, Dave Springford wrote:
>Schempp-Hirth gliders have a 6000 hr limit before the first
inspection, and
>if IRRC, all Schleicher gliders have a 3000 hr limit before the first
>inspection.
>
Not entirely. Many Schempp-Hirth gliders have a 6000 hours
inspection as their first lifetime extension, but not all. Some,
including the older tupes like Standard Cirrus, have it at 3000 for
the first time.

[[email protected]]

Does a service-life limit apply to an Experimental glider in the USA?

[[email protected]]

On Friday, November 23, 2018 at 7:53:22 AM UTC-8, Boise Pilot wrote:
> The three Blanik L-13's that just returned to service after having the world fleet grounding AD repaired now have 6,000 hour service life.
> Boise Pilot

Is that 6,000 hours from the date of the recent factory rebuild or 6,000 total time from when they were first manufactured? I've been seriously considering getting back into an L-13 in the future. The AD&C mod has been accepted in Canada for quite a while but as far as I could tell it only allowed 5,000 hours total time from date of initial manufacture so the cost would have been hard to sustain unless I could have found an L-13 with under 2,000 hours total time. The factory rebuild and mod seems much more promising, so long as I can find a decent L-13 when the time comes.

As long as I have a better flying year in 2019 I should be looking into doing the 3,000 hour inspection on my ASW-15B fairly soon.

[Casey[_2_]]

From Grob Astir CS Maint Manual.

Inspection Procedures for Increase of Service Time
1. General
The results of fatigue tests of wing spar sections have demonstrated recently that the
service time of GRP gliders and motor gliders may be extended to 6000 hours, if for
each individual glider (in addition to the obligatory annual inspections) the airworthiness
is demonstrated according to a special multi-step inspection program particularly with
regard to the service life.
2. Time limits
When the glider has reached a service time of 3000 hours, an inspection must be done
in accordance with the inspection program mentioned under point 3. If the results of
this inspection are positive or if any defects found have been duly repaired, the service
time of the glider is extended by another 3000 hours to a total of 6000 hours (first
step).
The above inspection program must be repeated when the glider has reached a service
time of 6000 hours. If the results of this inspection are positive or if any defects found
have been duly repaired, the service time of the glider is extended to 7000 hours
(second step).
When the glider has reached a service time of 7000 hours, the above inspection
program again must be repeated. If the results of the inspection are still positive or if any
defects found have been duly repaired, the service time may be extended to a total of
8000 hours (third step).
The gradual extension of service life will be performed by steps of 1000 flight hours up
to maximum 12 000 flight hours at this time (4th – 7th stage).
Additionally at 9500, 10500, 11500 operating hours, inspection of the wing connection
bolts and main spars spigots must be performed accordance to Service Bulletin TM
306-30, latest edition, action 7.

And the multi step inspection is straight forward, simple. Just need form from type holder.