This site will look much better in a browser that supports web standards, but it is accessible to any browser or Internet device.

Clubs, glossaries, museums, shops and much more......

...all of your model making needs from one site.

Grand Wing Servo-Tech Co Ltd GWS P51D

By: Dave Taylor

My first acquaintance with this model came when a good friend of mine had purchased one and asked me if I would like to take a look at the kit one evening. I was very surprised at the comprehensive contents. These included not only the wing and fuselage components and other airframe parts but also such things as engine and gearbox together with prop, glue and other small parts. To add to the completeness there is a very good instruction manual all 30 pages of it which is very detailed.

This was certainly one of the most complete kits that I had seen and all that is required to finish to a flying standard is battery, speed controller (BEC) receiver and three small servos.

The kit comes in two versions: one is powered by a 400 size motor and the other (which we have both built) is powered by a 300 geared motor turning a 10 x 8 prop.

The first three pages of the instruction manual are all taken up with specís and parts list together with the tools required and the extra parts required.

The bulk of the manual is then how to construct the model and I will not go into this as it is very comprehensive but if followed step by step you cannot go wrong and you end up with a P51 Mustang. I was in a lucky position in that my friend had assembled his and flown it so I had some idea as to what modís I would make.

The first slight modification was to gently rub off the mould marks using 700 or 800 grit wet and dry sandpaper used with a block of wood. This I did because I wanted to apply some paint to mine. The second modification was to use fast set epoxy to glue the parts together as I felt that it was more suited to my needs and is faster setting than the glue included in the kit. Before I had stuck the fuselage halves together I soldered the speed controller to the motor and kept the wires as short as possible. I also built up the motor mount and installed the whole assembly into one half of the fuselage putting the speed controller into the cavity behind the motor at the top. Next I took a sanding drum to the rear fuselage just behind the cockpit and gently removed some of the foam. Now whether this has lightened it much Iím not sure but it felt good to remove and itís weight taken off in the right place. Finally I glued the two fuselage halves together. Using as little epoxy as I could I spread the mixed glue over the joints and then removed most of it until the jointed area was just a little wet with glue almost a semi matt finish if you put it under the light. Using low tack masking tape to hold the two halves together tightly I left this over night to dry.

After the glue had set it was possible to sand the joint smooth using 800 grit wet n dry used dry with a block. It was also possible to sand off most of the mould marks on the airframe but unfortunately this also removed the silver finish but this was easy to replace using an airbrush. Another modification which I made was to cut the outer ailerons in from the outer tips at about 3 ĹĒ inches and re-glued them up slightly so as to give the wing a little washout which seemed to help at the slower end of the flying. So after I had followed the instructions to the end and had an airframe basically together I then sprayed it silver again using Humbrol paint thinned out with white spirits as any cellulose would melt the foam. After I had applied the silver I then looked around for a suitable colour scheme.

The one that I chose meant spraying medium blue over most of the airframe with a yellow nose and spinner which also fitted in with the self adhesive decals supplied in the kit.

When the basic colours had dried I did some weathering using some mixed matt black and various other colours. I also used a soft pencil and oil crayons together with some very fine 1000 grit wet n dry paper to gently remove some paint in the places where I thought would get wear and tear. This removed the top paint to reveal the silver paint below which gave a worn look when carefully done.

Next was to fill the cockpit with a figure and with a bit of luck I stumbled upon a nice vacuum foam one. These are available from Small Scale Custom Services. They take a little work to put together but the effort was very worth while. I do hate empty cockpits. So give Lindsey a ring on 01264 773487 and get a price list. You wonít regret it.

So here we have it the finished Mustang and from a few feet away it really looks the part but before we go off and fly we must check that the CG is within limits. To my pleasure it was spot on the middle mark on the instruction manual and this is without any lead at the nose. Now all there is to do is wait for the weather and a suitable day.

On arrival at the field there was a breeze blowing between 5 and 10 mph from the West which I reckoned to be just right. Just before I go into the flying I must say that I set the controls as instructed in the manual and at first I thought that these didnít look enough especially the elevator a 6 mm each way. Oh well if thatís what they reckon who am I to argue.

Ok so battery fully charged, controls checked and range checked. I have run out of excuses. So with the engine running I launched into wind and as set up gently climbing away and tried a turn and we banked over. Ailerons are quite powerful and it does tend to lose height a little but not too much. Next turn I used a little rudder and this made the turn look a lot nicer not losing any height and together with a little aileron these turns are better balanced and boy did they look sweet.

The elevator at 6mm movement is more than enough and requires a little care in its use and comes across as sharp. Itís flying a little tail down and this indicated to me that it was flying with a slightly rearward CG. So when we landed I altered this. I did a few more circuits and tried a roll but with this rearward CG a loop wasnít tried. The approach and landing went without too much of a problem and at an all up weight of 16 oz there isnít too much energy to stop. It is a slightly different approach and landing then I am use to. When you throttle back all the energy stops and the elevator loses its authority so a powered approach is necessary cutting the power at the last moment at about a foot above the ground.

For the second flight I added 1 grams of lead to the nose and some negative exponential to the ailerons and elevator Ė 16 to start with. So with a fully charged, 7 cell 500 mAh, battery pack installed. I launched it back into the circuit and immediately it started to feel better. So much so that I gained a little height and tried some loops and rolls and also was able to do some half cuban eights. The stall now is quite good and the nose can be brought up quite high with power on before the stall happens and it is easy to just lower the nose and fly away from this situation. Later into the flight I tried a full blown stall leading into a spin to the left. I allowed it to carry on with in spin controls to go for 3 turns at which point I brought all the flying controls to neutral and after half a turn the spin stops and a recovery was made from which I flew away from in level flight. The next spin tried was to the right and this one recovered quicker and again I flew away from it after recovery.

The more that I am flying this little aircraft the more I am enjoying it but to this I would add that if you pick your time and fly in light breezes and not in windy conditions it is a real joy to fly. Most gentle aerobatics are ok like loops kept a reasonable size and you donít try and stretch them to big. Rolls made with a little pitch up and then allowed to barrel are nice. It will if asked roll nice and axial. If you use opposite rudder and down elevator and then hold the nose up again with rudder these are ok. Most War Birds that I have seen tend to roll with a little elevator on and this keeps positive G on the airframe and if done at the right pace looks more authentic. When landing if you have left yourself some power for the motor you can easily touch down right by your feet using a little power.

The radio gear that I have used is three Hitec 55 feather servos guided by a GWS Pico 4 channel receiver with the throttle control by a Ripmax EXTRA 22 amp speed controller which is all linked up to a Seven Cell AR 500 mAh battery pack. The all up weight of my Mustang weighs in a 17 oz. which is a little over the quoted weight on the box but it can take some extra weight but not to much so donít go mad with heavier gear or paint etc.

So to sum up my thoughts about this little gem. I liked the building, very quick and you end up with a reasonable replica of a Mustang which you can display after flying indoors as there is no messy fuels dripping. I liked the fact that you can airbrush a good colour scheme on it if required.

The flying I feel needs a little attention as this is not your average low wing type and because of the electric motor is not the most powerful of planes. When you get use to this model itís one which you will not leave at home many times as you will soon be flying in the most unusual of places, parks, beaches and deserted car parks. Remember to always be aware of other people around you in public places.

So in conclusion I think this is a really great little kit and one which satisfies my building skills and airbrushing attempts as well as being a great little flier.

By: Dave Taylor