Sailplane Stories & Ressources

Video footage from past year

2011-11-19T16:48:00.001+01:00

Here is a video assembling different flights over past season. Those shots were flown starting either from my "home airfield" of Moissac (LFCX) or from different flying trip : Jaca (LECI), Bailleau (LFFL) & Luchon (LFCB).

Mountain flying + Family

2011-10-23T16:36:00.000+02:00

We spent, as a family, a day in Luchon airfield (LFDH), that stands so to speak in the middle of Pyrénées mountains, on french side.

The weather was nice for the kids to play outside, and grass runaway was very welcoming...

For dad, autumn thermal where just right to discover this new area. I was also happy to fly over the slopes I had quite much flown with models.

Friends showed me the way to spain...

The most amazing thing was magical october's light !

Flying Bailleau contest - 2011

2011-09-17T20:51:00.027+02:00

Again this year I did participate to Bailleau intl contest, a good compromise between flying & family, with quite a number of other kids.

A lot of glider...

... that stood iddle some time on the ground quite often due to a wet weather for august !

There was still some nice day to fly, overall less extraordinary than the year before...

Some fields were visited again, and again my daughter was so nice to come retrieve me !

Well, not many flight hours logged, but quite a lot chating !!

A week in Pyrénées mountains

2011-07-06T07:56:00.000+02:00

Again this year a very nice week flying from Santa Cilia de Jaca (Aragon)

Not so far away from the airfield, in France, Pic du midi d'Ossau is a nice sightseeing area.

Everyday so to speak, we were gliding along Canon de Ordessa, south of the famous brèche de Roland.

This area being a nature sanctuary, it was not to be flown directly over. Anyway prey bird such as Vultues, Percnoptère & Gypaètes were flying also outside of the parks ;-)

Sometime cloud where growing a bit too much...

... so that we went sight seing in Navarre.

Several time we flew close to each other for the sake of taking nice photo.

In the "wavelet" the view was all the most stunning.

In return I was taken some nice shots too.

Very nice week, and nice collection of images to be remember during cold winters !

Tracking from Jaca

2011-06-19T15:40:00.004+02:00

During this week in Santa Cilia, I will be carrying my Spot tracker.
You may follow were I am flying almost live !

See the Spot tracking page.

LS6 winglet project

2011-05-11T21:28:00.000+02:00

It has now been a long thought project : adding up my own winglets to LS6a "AD".

The story of the design and corresponding detailed aerodynamic analysis has been presented during XXXth OSTIV congress in Szeged (August 2010).

Here is the presentation.

Summary :

This winglet design has converged, using reasonnably simple method and pragmatic considerations
A CAD model, compatible with milling constraints, has been created by Flybiwo
A set of Navier stockes computation has been performed using TAU code (DLR)

It is now a matter of actually building and flying those winglet :-)

For different reasons (including funding...) the materialisation of those winglet is stalled for now. If you show an interest to it, don't hesitate to contact me !

matthieu.scherrer 'at' free.fr

LS6, a twin seater ?

2011-02-09T20:32:00.001+01:00

I plan to apply for a STC to use the LS6 as a twin seater...

;-)

More seriously, the family is now larger, will it be compatible with flying ?

Flying in Spain - 2010 video

2010-12-07T22:16:00.000+01:00

Some nice souvenirs of wave & thermic flying from Santa Cilia de Jaca in Spain.

Jaca in 2010

00:24 : "pic du midi d'Ossau", from Canfranc
00:55 : Monte perdido & Gavarnie
01:50 : Posets
02:13 : Vignemale's spanish side

Flying Bailleau Contest

2010-09-08T21:19:00.002+02:00

This year, I did participate to the 36th Bailleau contest, starting just south of Paris.
The nice thing : it was also a family time, as the airfield is nice and welcoming for children. Then mental preparation was really nice :)

Flying condition were quite incredibly good, with heigh ceiling, and 8 flight days out of 10. I flew the "long flight" category, and indeed we were launched on big tasks (twice 600km-ish circuits...). The objective for me was to progress, and I have indeed exceeded my longest flights, in term of distance as of duration. I also flew 490km at a mean speed of 107km/h, something I had never done before.
The difficulty was not to hit the airspaces that are everywhere in this region...

I also dicovered outlandings in real nice conditions, fields being generally biger then any airfield...

Thanks to all the crews that retrieved me (4 times...) in the fields. I even once had the visit of my daughter.

This was really a nice contest, a lot of km & experience gained, I wish I'll be back next year !

Jaca in 2010

2010-07-04T21:19:00.008+02:00

This year was again the occasion to fly from Jaca with some colleague from different clubs in SW of france.

There was some OTAN manouevers in the mountain, so that it was possible to spot nice helicopters just near the airfield (and then they were on the tops of the moutians...)

Beginning of the week north wind was quite strong, leading to wave conditions on the south side of the Pyrénées. Wind was perfectly perpendicular to the runaway, reaching 25kts at the time of landing !

After quite an energetic aerotowing, everything was much calmer in altitude... even with 120 to 150kph wind to deal with !

Thanks to my brand new oxygen system, I did'nt have to stop climbing so that I could reach more than 6000m ! First time for me (some colleagues even reached higher altitudes).

Being up there just felt like flying an Airbus sometime...

On the 1rst day France was fully covered with cloud, on the 2nd more nice mountains were visible, such as the Pic du midi d'Ossau :

Afterwards, the weather turns to more classical thermal condition, very enjoyable.
I have discovered new areas again this year : Posets, Aygestortes, and also the very nice Vignemale. Some films where taken, to be processed !!

Flying as a ground has made possible nice airshots (thanks Sandrine !) :

At the end quite some kilometers mainly in the mountain for me...

All this with a nice team !

Going north...

2010-06-07T21:35:00.003+02:00

Quite strange type of weather, but very good this spring. With some colleagues we had the opportunity to go further north than any time before, starting from our airfield. We have reached the area of "les monts du Cantal", which is a very old vulcano in the middle of france.

Here is Puy Mary area

Here is "le plomb du cantal", that is the highest spot :

I went also along this area, where I like to come flying models with friends regularly :

This was really a nice flight, to fly over this region I appreciate as a walker already !

Flying from St Gaudens

2010-05-11T21:13:00.007+02:00

I had the chance to fly three days from St Gaudens, nearby Pyrénées mountains, in the frame of a competition training cession.

Weather was not that easy to predict, but we have flown everyday...

As a result, short but intense flights.

Hopefully I was able to catch some nice images, such as flying over a rainbow !

A brand new glider

2010-03-27T18:48:00.002+01:00

Thanks to Nicolas, I have recovered safely my glider from Bruchsal, where the gelcoat was being renewed : a 2200km trip from Toulouse within 30hours.

It was worth it, I now have a brand new glider !

More color are to be installed...

Visite to Schleicher factory

2009-10-29T21:22:00.007+01:00

As a side effect of SDP meeting, I had the chance to have a tour in Schleicher factory, with Michael Greiner & Gerhard Waibel.

The main gate :

The assembly worshop :

Some fuselage...

ASH31 wing :

Flying in Spain - 2009 video

2009-10-11T10:40:00.000+02:00

Ready to fly ?

2009-09-01T07:32:00.000+02:00

Our daughter Eloïse seems to have got it all about flying...

Gliders in Iceland

2009-08-08T19:27:00.006+02:00

We had the chance to have a trip to Icelandn which is really aother country ! I had the opportunity to see gliders of two types over there.

First the "natural ones", particularly Fulmar which are soaring really well over cliffs :

And then the "imported ones", seen at Sandskeid airfield near Reykjavik (BISS)

According to local pilots, you can as well fly thermals, wave or slope (as on this day). The nice thing is that in summer you can fly at 11PM...

Sadly I had not the time to fly as proposed by the people there.

In Spain, again...

2009-07-19T19:43:00.006+02:00

Just like last year I have spent one week in Jaca, Spain, with flying colleagues from Airbus

Some classical place were flown : the high Sierras, the Ordessa Cañon nearby "la brèche de Roland" ...

... but also some new spots for me : the Aneto summit & its lakes.

More south, here are the "Malos de Riglos", funny stones coming out of the ground.
A very nice week indeed, good flying & nice sightseeing from my chait in the sky !

French 15m national

2009-06-07T09:58:00.010+02:00

I have participate for the first time to a french national, 15m class, taking place in Vinon sur Verdon. The other classes flown were two siters-20m (more or less DuoDiscus monotype...) & open class.

The area flown was southern french alps. I knew a bit the area, but with competition pressure I have done things I had never tried before (very low on slopes, things like that...)

It was a bit difficult for me at least at the beginning, two outlanding for starting, I choose to go to airfields soon enough...

Saint Auban, "Les Mées" in the runaway axis

Gap (Thank to Céline & Denis for the road retrieval)

For the next flights I was able to be back home !

It is quite difficult to take photographs during competition flight, as you are much occupied. Hopefully there was a few calm moment when it was possible to reach the camera.

In Vercors wave :

In Queyras, with Mont Viso behind the clouds :

I ended 18th out of 23, no very glorious, people used to flying flying in mountain were for sure in a better position. Still I have flown very nice flight, I did not get too much scared by the different situation in the mountain, & I did not end up into the rocks !
So very nice experience, for my next competition I may rather try flat area though !

You can find here the competition diary.

Back in flight

2009-04-18T20:03:00.004+02:00

Flying season is back!

I have choosen a lot of colors this year, the objective being to be seen by the other pilots.
According to my colleagues, this is very well done !

Some shot of "les gorges du Tarn"

Winter works

2009-03-01T22:53:00.004+01:00

This is winter, AD is receiving a full hard wax treatment for his gelcoat

As far as only the fuselage is concerned, a car can still enter the garage.

But when I need to work on the wing, nothing else than the bikes can fit the 7.5 length garage !

Flying in Spain - Video

2008-12-22T11:38:00.002+01:00

It is winter time, the period to sort photos & videos of the flying season...

Here are some "souvenirs" of energetic flying with AD from Jaca airfield.

Nice shots in la Montagne Noire

2008-12-22T11:34:00.004+01:00

Very nice photos taken during the last 2008 SWAF meeting :

http://julienbersheim.blogspot.com/2008/11/week-end-swaf-la-montagne-noire.html

http://www.flickr.com/photos/wabgs/sets/72157609168824410/detail/

http://yves.calzetta.free.fr/Telechargements/Videos/Grandeur.wmv

Sadly I was not flying this day, even if it was planned...

Article published in Technical Soaring

2008-10-09T21:34:00.003+02:00

Last July my article on Flight Template has been published in technical soaring. Flight Template is a tool to be used for aerodynamic optimization, based on statistical study of igc files.

See also the article from Christof Maul, another kind of statistical study based on IGC file.

NB : a copy of Technical soaring can be get at OSTIV : http://www.ostiv.fai.org/

New technical paper

2008-08-29T08:15:00.003+02:00

I have issued a new technical paper on my (old) web site. It is concerned with some method to implement automated wing optimization scheme with constraint span.

The paper is available on my publication page.

Visiting OSTIV congress - WGC 2008 in Lüsse

2008-08-15T16:42:00.008+02:00

I did take some time to go to Lüsse (near Berlin) during last World Gliding Championnship, in order to attend OSTIV congress

It was a nice occasion to see a big competition running (more than 130 gliders !).

Among the glider where the last up to date gliders : ASG29, Ventus 2cxa, and also Diana, Lak 20 and JS1 from south africa.

And there was also "nice oldies" on show...

In the Alps - Video

2008-08-14T18:10:00.001+02:00

Back from the Alps

2008-08-06T09:53:00.011+02:00

We have spent 2 weeks in Aubenasson, over the "Roche courbe" moutain.
This is a very nice place, were you can fly and benefit from the family as well !

Here is a summary of the flights perfomed from this airfield, between 50 and 440km per flight. It is possible to have some wave, both with NW & S winds.

Flying to Le Pic de Bure from Ceüse

Lac de Serre-Ponçon

Grand Veymond & Mont Aiguille

Glacier Blanc ...

... & Glacier Noir

Finally a nice "shot on top"

This was a very nice holyday period !

More info on Aubenasson at :

http://aubenasson.volavoile.free.fr/
http://planeur-aar.over-blog.com/

Another photo in Spain

2008-07-15T09:11:00.002+02:00

AD taken from the Midi-Pyrénées DG1000 :

Flying in spain

2008-06-24T08:01:00.010+02:00

I recently spent one week in Spain, flying from Santa Cilia de Jaca. Here are some nice pictures !

Santa Cilia Village

The airfield

The colleagues who helped me
discovering this nice region in flight

AD ready to go

Here is a summary of the 4 flights performed with AD during this week :

Also some nice pictures from the sky during those flights :

Cross country sailplane computer

2008-05-24T10:02:00.011+02:00

Here is a computer for sailplane cross country flying. It helps at flying in security while taking the full benefit of sailplane performance.

This is "old school" stuff, I have been taught into this by François Ragot, who was in the WGC once in the 50's - 60's. It is a 100% failsafe device !

Two version of the computer are available :
- The initial "big" version, ideal to learn to compute with.
- The panel version, to be placed among others instruments.

A short user book is also provided.

Download the computer.

The panel version is installed in my LS6, I use it in parallel with Cambridge 302/303, as another (failsafe ;-) ) source of information.

If you happen to build this computer, just send me a photo of it : matthieu.scherrer 'at' free.fr

Results from the Wind Tunnel

2008-04-25T12:35:00.012+02:00

Some time has been already spent analysing wind tunnel results, they can now be presented, at least partly.

Here are screen shot of drag polars, as obtained during the test.

Note that the test were repeated over the different days : it can be seen that reproductibility of the result is not garanted at low speed (V=20m/s).

The Excel file containing the summary of results versus predictions can be found here.

Thanks again to the participants for accepting their prediction to be compared to measurements from the windtunnel !

Nice shot !

2008-03-22T14:01:00.006+01:00

Here is a nice photo arrangement of AD in the garage, made by my brother Vincent.

End of the wind tunnel cession

2008-03-21T15:33:00.003+01:00

Today was the last time of wind tunnel testing.

Some bugs in the coefficient have been detected, some post processing will be necessary before releasing official data. So that comparison will not be possible before some days.

Please be patient !

Some news from the Wind Tunnel

2008-03-19T20:34:00.004+01:00

Here are some photos from the wind tunnel.

As the operating & recording system of S4 wind tunnel has jsut been updated, it is likely the release of the results will be delayed. Proper check of all the results will be necessary first.

Aerodynamic prediction worshop - End of prediction period

2008-03-17T20:05:00.008+01:00

The Jibe 2 is entering the windtunnel this week. Today was riging period, tomorrow will be the first test with wind on.

Now the period for prediction has ended ! Here is a summary of the result i got, from 6 differnt people / team.

The excel file with more results.

Next part will be the comparison with the outcome of the test !

Here are some details about the methods used for those predictions.

	Method
MSch	Wing & tail + interaction : Miarex (Xfoil/lifting-line coupling, N=9 for wing, N=2 for tail) Fuselage : Xfoil + Mangler transformation Lateral : AVL + drag effect in aero axis (Miarex)
TPla	Xfoil plus 3D transpositions Simplified Cdi assumption Fuselage effect on Cm from in-house rule (from flight test & statistical approach)
ADe	XFLR5-V4
Jo&Stef	VSAERO : Linearized potential code, coupled with BL calculation
PLu	AVL for stability & induced drag Xfoil for airfoil drag with N<5>
FMe	XFLR5-V3

LS6 interior refurbished !

2008-02-24T09:53:00.004+01:00

The interior refurbishment of my LS6 (AD) is now finished.

The masterpiee (if I can says so...) is the hand carved wooden stick, made from a footboard...

At least it makes it unique !

The fuselage was also polished.
I am now thinking of which decoration to create for the season to come.

Model aerodynamic prediction workshop - Update

2008-02-23T07:59:00.004+01:00

Some update concerning Jibe 2 wind tunnel test project.

The preparation of the wind tunnel test by the two students in charge, Thomas & Sylvain, is still ongoing.

The wind tunnel cession will take place at S4 facility between the 10th & 14th of march 2008.

The airframe to be tested was just received from Flybiwo.

It must be prepared for receiving the inner measurement balance. Aileron & elevator will be installed, and their efficiency evaluated.

News from the workshop

2008-01-23T08:10:00.000+01:00

A wing can just fit in my workshop, with door closed !
Not a lot a room to walk around though, I should rather work at it with the door opened !

Also some photos of the internal refurbishing. Next will be the wooden grip for the stick, which is under shaping !

This was before :

and this is now :

Model aerodynamic prediction workshop

2008-01-07T22:34:00.001+01:00

I have the opportunity to organize a wind tunnel test cession on a F5B model airframe from François Lorrain.
A student team from ISAE has choosen the Jibe 2 model for an aerodynamic evaluation within S4 wind tunnel.

More information on the WT model

I find interesting and profitable to build up some emulation around this project among those who practice/masterize aerodynamic calculations.

There is here a nice opportunity to have an experimental feedback, and not only compute in "open loop".

Ipropose to organize a "Model aerodynamic prediction workshop" : the objective is for you to forecast what the outcome of the wind tunnel test will be, using whatever means ranging from rule of thumb to NS or LES computation .

The test should take place in March 08 (week tbd), with the complete airframe but the propeller off. Investigations will be performed with a 6axis balance installed, measuring both in longitudinal & lateral, for having a complete views of aerodynamic coefficients (performance & stability derivatives).

If you happen to be interested in joining this, I have prepared a file containing a priori all the information needed about Jibe2 geometry, with the kind agreement of Francois Lorrain.

Your results should be sent to me before beginning of march to be published.

matthieu.scherrer 'at' free.fr

Then we will carry on with the wind tunnel test, and see the outcomes !
I will try to ensure a proper following through on by blog.

Well, here is the idea, let's make it interesting ! Any input will be anyway profitable to the community !

Season greetings !

2008-01-02T22:29:00.001+01:00

Wing inertia

2007-12-29T09:45:00.000+01:00

For handling quality studies, mass distribution & inertia the saiplane are part of the eigen modes solutions.
It is nevertheless very difficult to access such data among existing sailplanes.

Here is a simple spreadsheet tool that evaluate inertia of a wing on main axes (Ixx, Izz, Iyy) .

Some simplifying hypothesis are made (wing seen as a beam, simplified mass distribution, etc), in order to be able to evaluate realistic values of inertia.

Inputs :

estimation of the spar & "skin" mass
geometry elements
water quantity

Simplifying hypothesis are made about how to spread/share thoses mass along span & chord. The effects of filling tanks is also evaluated, once again with some hypothesis.

Outputs :

Inertia/ inertia radius, at elements CG
Inertia/ inertia radius, at wing CG
Inertia/ inertia radius, at a reference point

Similar modeling will be needed for fuselage.

If you happen to have data on sailplane inertia, just tell me !

2007 cross country flight with AD

2007-12-20T07:37:00.000+01:00

This is winter, right time for reviewing the outcome of 2007 flying season.

Approx 50h logged in the LS6: this year was a quite disappointing season, partly due to weather situation this summer.
Here is a general view of cross country flights performed with AD.

Best performance was 360km. I am still not a big champion, nevertheless I do like those rides a lot !

LS6a command system

2007-12-16T14:51:00.000+01:00

I am "opening" the LS6 for checking purpose. This is the first time I work on a flapped sailplane, so I watch carefully how it is done !

Before removing the seat, everything is carefully faired :

Once removing the seat, here is a general view of all the cranks and tubing from the stick, AB & flaps levers.

Then a detail over stick area, with the big green trimm wheel.

Finally the mixer, that commands the flapperons

Model

2007-12-05T06:54:00.000+01:00

As I wrote, a lot of things have started for me with models.

Here is my last model, fresh out of the molds...

Eloïse (so is she named) is in good health, as is her mother !

Proudly, Matthieu

Mesured sink polar of LS6

2007-12-01T21:12:00.000+01:00

Here is the scan of original LS6 sink polar, as measured by DLR back in 1986 :

The reading of this polar has confirmed to me the way to fly (without water):

Do not use flap -5 before 150kph !

Then, up to 150 kph you are virtually flying a LS8...

Preparation of technical study of LS6 glider

2007-12-01T19:53:00.001+01:00

I am collecting as much technical information as possible about my glider type.
if you have any information, please don't hesitate to contact me
matthieu.scherrer'at'free.fr

The objective is for me to test available tools for aerodynamic computaton and prediction on a precise book case. I base my study on on LS6 measured planform and wing airfoils.

The geometry of LS6 wing have been translated for MIAReX, my tool coupling lifting line theory and Xfoil results.
The final objective is to test how accurate such a tool could be at predicting the speed polar, and have a first hestimate of non linear behavior of the wing for handling quality evaluation.

I have also been preparing the formated file for having the complete saiplane geometry of LS6 available in AVL.
The objective is to be able to study the rigid, linear handling quality of the LS6 glider over its flight domain.

Using those tools, I hope to progress in the understanding and prediction of the aerodynamic of sailplanes, and mine in the first place !

The LS6 in the worshop

2007-11-30T08:23:00.000+01:00

This is winter, the LS6 is now grounded and is waiting in the worshop to be fully checked.

The first task was to build a proper bench for handling the fuselage :

Now the car has a friend in the garage !

Slope flying with the LS6 at "La Montagne Noire"

2007-11-30T07:58:00.000+01:00

Some nice souvenir of two flights from LFMG

Old timer flying

2007-11-26T21:53:00.001+01:00

I had the opportunity to fly some old timer sailplane from APPARAT group. this was a big time for me, as I have mainly flown fiber ships !

First was french Breguet 905 "Fauvette". This is a V-tail, 15m wooden sailplane. Very light to handle, the V-tail mixer is at first surprising, but once used to it you hardly notice it !

Then I had the chance to fly the Slingsby T-21 with Julien. This is a british side-by-side twin seater. Aerotowing is a big story, as you fly far too quickly for this old lady ! Once free, flying at 60kph it is much more bearable to have the head out !

Nice souvenir !

First message

2007-11-26T21:16:00.000+01:00

Publishing on the Internet takes time, so that very often I have not the courage to create new pages. On the other hand, with the developpement of blogs, it is now possible to very quickly edit information.

After 10 years with a classical website, I will try with this blog format.

I hope I will then be able to update this blog more often than my web page, and to keep you interested with my sailplane adventures !

My old web site is kept in current state, and is still available at this address