Wonwings Diary-a blog with a difference.

[Guest]

Oh man.......You cant leave it hanging like that!!!!!

Next episode please Yoda!

[wonwinglo]

Wonwings diary-The trials and tribulations of a model Spitfire-Part 2.

Suitable weather again and virtually a new rear fuselage after the rebuild it was off to the flying field,the usual through checks were undertaken including a full power run up with the Spit held vertically to make sure that there were no fuel flow problems that showed up on the ground,the following account just goes to show that gremlins can creep in at any time and never to take anything for granted with aeroplanes whether model or full size,the take off this time was un-eventful and the model climbed in a nice level attitude,after about 300 feet it was time to throttle back and check out the trim,the nose dropped and I added a smidge of up trim to make her comfortable to fly,she was flying a little to port throttled back so I added a bit of aileron trim to compensate,then I decided to open her up and do a few circuits,well that was my plan but for some reason unknown at the time the engine would not respond to throttle,now a big Spit like this has quite a high wing loading is is no glider she needs all the power that you can get,you need to keep motoring a model like this around the sky,and this one was loosing height on a fickle motor,what could be wrong as the engine was still running ? well she also had a large fuel tank to cope with the big guzzly motor,so it was time to try and get her down to a landing,well that was easier said than done,she was just about maintaining altitude but needed some careful flying with no engine reserve,I tried long wide circuits but every time that I lined her up into wind she would loom up again holding onto that power setting,this was hard work,to cut a long story short half an hour later the engine finally cut and I had to make a smartish dead stick landing and get it right first time,no luxury of a go around this time,she landed a bit heavy on the main legs ripping out the undercarriage legs and slithered to a halt,she was down at least.

Investigations found that the throttle servo ( a new one ) had failed leaving the throttle pushrod in a set position,never had a throttle servo go before but lost models where aileron servos had failed in flight,the soft balsa had reared its ugly head again with very little support in the wings for the undercarriage,modifications were made and the wings repaired,the only problem with such major repairs is the extra weight penalty incurred,but I thought that one last try at least to see if I could get a respectable flyer out of her.

After a few weeks work back to the strip again,everything checked and functioning with a new throttle servo installed,another take off and things were going well,even a slow roll or two,after all what good is a Spit if she will not roll ? then a loop nice and wide against the blue sky,lovely she really looked the part,I did not attempt a spin having lost heavy models that would not pull out but was happy with the simple aerobatics,right time for a few touch and goes to get the feel of the circuits,throttle back and downwind leg,nice square approach and into wind lining up with the strip,wheels just touch,open up and repeat it a few times then with fuel running low time to get her down on the ground,as she touched this time there was another crack,not the back this time,in fact nothing vey visible at all ? what could it be this time ? and then I spotted some stress cracks around the nose area,what had happened was the soft wood and inferior adhesive used had given way obviously with the vibration of the big motor,this had previously been hidden from view and not having built the basic model I was not aware that she had been glued with balsa cement ! fine for small scale models but nothing as large as this beast.

So the decision was made to withdraw her from use and there she lay for ten years until the other day when everything was removed,there really was nothing that could have been done as it would have been inpractical to even get at everything,when you build something yourself you know the quality of work that goes into the model,but something like this was an unknown until you start to place stress onto the airframe,then as happened here things start to show,the basic error on the part of this builder was not to grade the wood,soft balsa is fine for non stressed areas but not for major load bearing areas,also the prudent use of plywood re-inforcement would have helped considerably.

[Guest]

A truly sad end after so much hard work.

Every build tells a story. Thanks for sharing Barry.

[wonwinglo]

Wonwings diary-More rundown on Lithium batteries.

After a lot of research on Lithium batteries here are a few things that dispell some myths on the subject,it should prove very useful to prolong the life of these batteries-

A lithium-ion battery provides 300-500 discharge/charge cycles. The battery prefers a partial rather than a full discharge. Frequent full discharges should be avoided when possible. Instead, charge the battery more often or use a larger battery. There is no concern of memory when applying unscheduled charges.

Although lithium-ion is memory-free in terms of performance deterioration, batteries with fuel gauges exhibit what engineers refer to as "digital memory". Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery's state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate.

Aging of lithium-ion is an issue that is often ignored. A lithium-ion battery in use typically lasts between 2-3 years. The capacity loss manifests itself in increased internal resistance caused by oxidation. Eventually, the cell resistance reaches a point where the pack can no longer deliver the stored energy although the battery may still have ample charge. For this reason, an aged battery can be kept longer in applications that draw low current as opposed to a function that demands heavy loads. Increasing internal resistance with cycle life and age is typical for cobalt-based lithium-ion, a system that is used for cell phones, cameras and laptops because of high energy density. The lower energy dense manganese-based lithium-ion, also known as spinel, maintains the internal resistance through its life but loses capacity due to chemical decompositions. Spinel is primarily used for power tools.

It is essential to use the correct ESC Speed controller with this type of battery,the special controllers automatically cut off the supply to the electric motor but allow enough reserve on the BEC for the radio,the use of standard speed controllers will lead to certain battery failure with lithium types,once they go beyond that crucial voltage then they cannot be retrieved,once the battery has cooled after use charge up again and store in a cool place.

Whilst these batteries are superior to anything we have today in terms of capacity giving long flight times,they do require very careful use if early failure of the battery is to be avoided.

Never use a standard charger for Lithium,use a dedicated lithium charger,this can be one of the special one battery pack chargers to the more sophisticated 'cell count' Chamaleon units available from specialist model shops.

[wonwinglo]

Wonwings diary-More on the Autogiro.



The delightful little Dinky Toys Cierva C.30A (shown here aprox twice size ) Autogiro produced by Meccano circa 1936,the boy of the prewar era could look skywards and see one of these never to be forgotton machines in action,I was lucky to see the last one flying back in the fifties,it rattled overhead my house heading towards Birmingham,see the pictures of G-ACUU below.

(Authors collection )



American Pitcairn Autogiro die-cast made by Tootsietoy U.S.A and later copied In the UK by Dyson ( no not the vacuum cleaner manufacturer !) as in Britain America was fascinated with the introduction of the Pitcairn machines,these toured America one landing on the frontage of the White House,Ciervas patent was spreading world wide,such a pity that his tragic death in a take off crash at Croydon airport in a Douglas DC-2 airliner put a sudden end to the development of the autogiro.

(Authors collection)



This fascinating picture was taken in the summer of 1931 when Regie Brie a pioneer aviator popped into land at the playing field of his old school at Bishopshalt school,Hillingdon.Mr Brie is standing just behind the port wingtip of G-AAYP Cierva C19-IV (Avro 620) behind the wing with a rosette in his buttonhole is the then headmaster Mr John Miles with the head deputy Mr.A.F.Gotch.

The autogiro was scrapped a year later in 1932.

My thanks to my friend Roy Boyle for the picture.





Penguin model of the Cierva C.30A Autogiro,this was known as the Avro Rota whilst in R.A.F service,the autogiro was used for radar calibration duties during the Battle of Britain.

Thanks to Peter Van Lune for submitting these pictures from his extensive historic collection of Frog Penguin models.



G-ACUU Cierva C.30A Autogiro when with the Skyfame museum at Staverton,this aircraft was formerly owned by Guy Baker and based at Elmdon airport in the sixties,its sister machine owned by Rotatowels Ltd G-AHTZ was written off on 04-03-58 when it turned over and burnt out at Elmdon in full view of the then Lord Mayor of Birmingham about to board his flight.

This is the machine that I witnessed flying overhead my house many years ago.



The very same Cierva C.30A G-ACUU taken at Elmdon in the sixties by Terry Lee.The other sister machine was G-AHTZ ,which turned over and burnt out here on 04-03-68 right in front of the then Lord Mayor of Birmingham who was taking his very first flight in an aeroplane.

The autogiro could in fact make a jump start into flight by spinning up the main rotor,it is ironic that most of the technology learned in the autogiro was incorporated into the helicopter as wee know it today.

[wonwinglo]

Wonwings diary-yet more on Autogiros.

Lets revel in these fascinating machines from yesteryear-



The rotor head of the Cierva C.30A Autogiro,here you can see to good advantage the floating blades,the advancing blade lifts in flight something that Cierva worked on for many years to get it right,modern day helicopters use the very same system albeit with different linkages,see the cut away drawing below to study the system.



Pitairn Autogyro,note how the blades are linked with cables something that Cierva tried on some of his earlier autogyro designs,note also the fairly extensive stub wings to support the load of the large blades.



Ryan XV-1 a later day Autogiro developed for the U.S.Army.



Tootsietoy/Dyson Autogiro even has the original white tyres,a little perished and hardened.



Cierva C.30A at Contrao Ventos stored with the Spanish museum.



Main rotor assembly removed from a Cierva C.30A Autogiro showing the substantial fork end of the blades.



Period 'Flight' magazine cut away drawing of the Cierva C.30A Autogiro,these drawings are works of art in themselves.

[wonwinglo]

Wonwings diary-Out & About-Fenland/Holbeach Daffodil rally fly-in.

The Vintage Aircraft club had a Daffodil Rally Fly-In at Fenland airfield on 15-04-2006 which proved very successful,Roy Moore from Tamworth,Staffs kindly sent in these photographs of the day,this just goes to show the importance of taking along your camera to record these events,and once more share them with forum members here,well done Roy.

So whether it is a traction engine rally,vintage cars,airshow etc get clicking,you supply the pics and I will add the words,fair deal ?



PA-34 Seneca G-BSUW belonging to NPD Direct Ltd,Spalding landing at the all grass airfield at Fenland.



G-AJON Aeronca 7AC Champion of the Oscar November 92 Syndicate.



G-CUPS Yak 52 from the Fenland Flying School is an IDA Bacau built example,this popular machine was built in large numbers.



G-PDOG GP/24550 Cessna 305C Bird Dog owned by Justin Needhams lines up for take off at Holbeach St John ( Fenland ) a friendly small airfield.

This is the only example of a flying Bird Dog in the UK,note the rockets under the wings ? bet that turns a few heads in the circuit !



Max Holste Broussard G-BWLR 44-CA/185 from Upton Bishop,Ross On Wye, seen on finals,the aircraft has been owned by Chicory Crops for some years.

The design was used by the French Army as an observation aircraft.



Luton Minor G-ASML always a delight to see.Mr Slaters pride and joy.

The design is a successful pre war ultra light aircraft.

[wonwinglo]

Wonwings diary-The Next Generation Freighter,fly her now.

Airbus A400M The freighter of the future.

The new A400M Airlifter flight simulator software is out today. The A400M is the next generation of military transport aircraft. It is being built by Airbus and is scheduled to fly in 2008. It will be used by the Royal Air Force, as well as the French, German, Spanish and South African military. This simulation of the A400M has been developed by Wilco and will give flight sim enthusiasts the chance to fly the transport of tomorrow.

The superb software is a credit to Justflight,here are a few screen grabs to see the attention to detail.

[wonwinglo]

Wonwings diary-The Airbus A380 in miniature





Just as I was wondering how to obtain a kit of the Airbus A380 for my collection,this little beauty came along,it was a gift from an employee at the Airbus factory,what a kind thought and I am most grateful and it will be treasured,apparently everyone connected with the project was given one of these 1=400th scale models made by Dragon,this one was a spare which has come my way.

Having watched the programme yesterday,on the Discovery channel about how they solved the logistics of moving parts from Hawarden in the UK to the assembly factory in France, via barge and lorry,it made me realise what a project this has become,the combined efforts of thousands of people have evolved into a machine that will change the course of en-masse commercial air travel history,aviation takes on some interesting tangents over the years and this is set to become one of them.

Ten years from now we will be wondering what all the fuss was about ? but will the roads and rivers of Europe govern the sheer physical size of future transport aircraft, given the problems involved in moving large components with this one.

I look back and marvel at the sheer size and complexity of its structure.

[Guest]

Barry,

Is the model of a prototype?, where are the passenger windows?

[wonwinglo]

***Well spotted Richard,see here http://www.airbus.com/en/aircraftfamilies/a380/a380f/

She represents the freighter version of the family,you could get a lot of freight into that space,even an airborne disco dance,the possibilities are endless ?

Will we see Fedex Airbus 380F aircraft in the skies,who knows ? Airbus are obviously exploring every inch of the market potential to reap back the millions invested.

Barry,Is the model of a prototype?, where are the passenger windows?

[Guest]

According to your link Barry Fed-Ex are already customers!! along with UPS.

By the way I have a lot of Justflight add ons for my flight simulators and I am always impressed with thier software.

That A400 looks quite impressive but I do tend to prefer things that I can chuck around a bit more!!

Probably why I prefer CFS and Stormovik to get my flying kicks.

[wonwinglo]

Yes I noticed that bit after my posting about Fed-Ex,interesting that they have explored the freighter potential alongside the passenger versions early on.

Justflight are the tops for quality and detail with their software packages,if you want something to test your reflexes then a Pitts Special is fun,there are some good freebies on the simviation site for aerobatic jobs.

[wonwinglo]

Wonwings diary-Lets build an electric version of the Frog Tomtit.

The Frog Tomtit was one of a series of first class kit designs kitted during the late fifties and sixties,they utilised a clever sheeted type of construction which went together well,above all they flew exceptionally well and were well designed models,I had hours of fun with mine and it proved to be a model that could be relied upon to perform well at a moments notice provided that there was sufficent rubber available,my interests in this design were re-kindled when someone on the internet provided some of the original drawings,with a pair of dividers,some wallpaper and a pencil a drawing twice size soon evolved,my plans were to make an electric version of one of my old time favourite flyers,a new Tomtit with a tiny geared Perkins cheapo motor,once more the motor was radial mounted so all that I needed was a simple bulkhead to mount it to,in fact this was not necessary either because two obeche bearers with two wire hooks sufficed to hold the motor neatly in place with the humble self tensioning elastic band ! there were no surprises when on the first flight she took off from a strip of tarmac and climbed like an homesick angel skywards,I was thrilled to bits on the models performance with that small motor,if you have not yet tried building a small balsa electric model especially from a time travelled design,then you just do not know what you are missing,scale them up either photographically by taking the plans down to your print shop or get out that old school draughting set.

The Tomtit design was kept as original as possible only allowing for easy battery compartment access and wings held with tiny magnets,these have proved reliable and crashproof,whilst my old rubber model flew at about 100 feet free flight,this one will easily climb to a speck in the sky under sub miniature radio control,she really is my favourite small flyer at the moment,so clear the bench and lets build.



First raid your balsa stock and select some decent medium grade wood,forget the pulpy type we need good straight grained timber such as that shown in the photograph above,make up a set of parts first then you will be able to carry on with the model,cut the ribs as a block of blanks,these are then shaped with a razor plane,sanded and the slots filed into place checking with the spars strip wood size,make laminations of 1=32nd wood for the wingtips wound around thick card templates,sheeted tail have anti-warp inserts,use aliphaetic resin adhesive for the construction and use dabs of cyno to assist the assembly,work cleanly and enjoy the build.

Dressmakers T-Pins are a godsend to hold parts onto a home made balsa building board with transverse end pieces to avoid warping,it is a lovely material to use for building,you can also bond hard balsa to MDF board for a super flat building board,use contact adhesive for this job,well woth the cost and effort.



Lay out the first fuselage side flat onto the bench,place the formers vertically checking with a small engineers set square,next add the second side after the first dried out overnight,no harm in adding great strength at the corners with strip wood,the whole lot evolves into a tough box structure whereby the decking and nose cowl are added,the central pylon has been centered within two formers,this takes the top wing which simply slots via the lower spar,the magnetic wing struts hold the whole lot in place and two more tiny magnets lock the lower wing,a singular elastic band adds aerodynamic integrity via two small dowels fore and aft on the centre pylon,always keep the tail end light as possible to avoid any excessive dead nose weight which contributes nothing to the way the model will perform.

The nose hatch is two laminations of 1=32nd balsa bound around with masking tape until the adhesive sets,a simple elastic band and toothpick pegs holds that little lot in place,anything that you need access to give a bit of thought to,this avoids fiddly flustrating on the flying field when you should be enjoying your flying ! make sure that you do not build a 'banana' into the fuselage,when pulling the sides in use the squares on your self healing mat using the best of tools,your Mk.1 Eyeball.



The electric motor is trial fitted at this stage via the two ledge bearers,any sidethrust trimming adjustment can be easily added by shaving off a bit of the wood and re-seating the motor,the nose cheeks are laminated balsa,give the whole lot a good sanding working down to fine crocus paper,then give the whole lot a coat of thinned down PVA adhsive to seal the grain,and prepare it for the Jap tissue covering.



Here you can see the two degrees of downthrust which proved adequate on the model,the balsa block nose provides some protection for the electric motors main shaft encased in plastic with a brass bearing at the front,with the gearbox at the rear,note the built in top wing incidence on the cente pylon,everything is kept simple and practical,this is a sports fun model with the emphasis on plenty of flying fun.



Micropore surgical bandage is used for the hinges sealed with cyno flooded into the weave,keep adhesive away from the centre hinge,a piano wire bridge locks the two elevators into place,small control horns are cut from scrap ply,the control rods are carbon fibre or piano wire can be used bound to the ends of balsa strip with the necessary end fittings ( tip-use one end fitting for adjustment and simply bend the other at right angles into the servo arm,this can be secured with a swing-in keeper )



The parts laid out all ready for covering with Jap tissue applied wet (Tip-lay tissue onto a towel,spray with water,lay the towel over to absorb excess moisture,then offer to the airframe ) note gussets at crucial joints,strong and light,laminated wingtips are vey strong even springy when a wingtip touches the ground,when tissue is dry apply a coat of highly thinned PVA and the tissue tightens like a drum,stronger and not so brittle as clear dope which will be withdrawn in a few years time anyway,so get used to other systems now.



Partially covered with Jap tissue,on biplanes you can cover the lower wing bottom surface,and the upper wing top surface first,then make up and fit the struts,adding small blocks at the strategic points,place writing paper rings around where the struts enter the covering and cut through the centres with a sharp knife,spend time in these areas and you will be rewarded with a neat arrangement that is also serviceable.

[wonwinglo]

Wonwings diary-Lets build an electric version of the Frog Tomtit,Part 2



72 hours later a model almost ready for its first flight,in fact as usually happens it was two weeks before that happened due to awful weather,here you see the model has had its upper wing covering added and the wing struts fitted,the lightweight wheels proved adequate with foam tyres,undercarriage struts are balsa with Micropore to hold them in place,the single elastic band wing retainer proved adequate for straight and level flight,if doing aerobatics add three bands,the model will loop and roll easily even on rudder and elevator,to perfom a roll just bring her pointing into wind,dive a little and pull up into a sharp climb,then input some rudder and over she will go,spinning is easy,full up and left rudder,enter the spin,release controls and recovery is automatic on the Tomtit.



Top cowl fitted and all ready to go,take care with no heavy paint and rely on the colours of the tissue for adequate decoration,the stars are cut from Solartrim applied over a thin sponging of washing up liquid and water to aid the slideability,pat out the bubbles trapped and allow to dry.

Rear view showing the models attractive lines,simplicity is the keynote.