A Me 263 or is it J 247 from a Cloud Models Me163

[Erfolg]

I looked forward to Cryril Carrs Me 163. Everything about the concept ticked the boxes for me. Designed by CC, so would be a foam type construction and the size spot on at 52" span.

Oh dear the reality did not life up to my expectations. Foam yes, but so little detail, the plan was little more than a personal sketch for CC. For the rest of us (that is probably me) there was no build pictures and the build text was not as good as i had hoped.

Some will know, that I now principally fly sports models, doing very little Glider Guiding. Increasingly i look to models that take off from the ground, seeing a reducing number of volunteers for the traditional chuck, as the age profile increasingly heads towards 3 numbers.

With all this in mind, I really wanted a Komet that had wheels, although I have converted my Cloud Models 163 to dolly take off. As yet i do not know how it will fayre in the field.

I have several books that deal with the history of the 163 and was aware that a few wheeled conventional UC aircraft were built.

Again I wanted a quick build model, so a re detailing of the CC wing for a conventional build, was not attractive, taking to much time. Plus the CC 163B, has blended wing roots, which take a little care and time. My mind now turned to a Cloud Models kit and modifying the body to a wheeled version.

It quickly became apparent from various sources that sections were added to lengthen the body, the method used was possibly not the simple method that Fw did with a 190A body inserting a straight section to make a 190D. My mind then turned to just buying a set of wings. Although a 52" version would have been preferred, the 38" Cloud set would be the easiest and cheapest way forward.

The rest of the build is based on a Cloud Models wing and information principally from this book.

[Trevor Crook]

Erfolg, forgive me if you know this already, but Hobbyking UK stock an unpainted kit version of their Me163. It costs about £50 and comes complete with the servo and mechanism for the dolly. My son has one and finished it as the Mitsubishi copy - Japanese prototypes were finished in a bright orange and he thought that would aid visibility. A set of German markings are provided.

It flies suberbly, with vertical climb performance without the optional rocket! Take off from grass is pretty good, although with its narrow track and no suspension it is susceptable to bumps. The motor/esc is available separately if you can't source one. Well worth a look.

[Erfolg]

Trevor

I have built a Cloud Models 163 in the past, which I have attached (a detachable, eh) dolly. The Dolly is a HK 163 modified item.

The Cloud version also flies very well, other than needing a good launch to get it going.

It is a model with wheels that stay attched that I want.

[Erfolg]

I do not know about others, i like to know a bit of the history of an aircraft, from the design phase, testing and service.

In the case of the 163, it was always troubled by the lack of a UC, which resulted in difficulties in ground handling. Also its short duration under power, became an increasing issue, as air superiority over Germany was lost.

It was to remedy these issues that a wheeled 263 were meant to address.

It became apparent although that Messerschmitt company was instructed to develop such an aircraft, they were less than enthusiastic. Some was internal politics, in that the 163A was very much the product of Alexander Lippisch, which Messerschmitt staff had to re-engineer into the 163B that entered service. It would appear the process was not harmonious due to Lippisch having his fixed ideas and concepts and messerschimitt staff, determined to productionise the aircraft in a fighting machine. The other major problems were the heavy work load i modifying the 109 into its variants, whilst also producing it. Dealing with the successor to the 110, did not go well, ending with the 410 after a debacle with the 210. The demands of the 262 also made demands on the design and production staff. Then there were a myriad of other in house design projects.

The task of a revised 163 was initially given to Klemm, who apparently had great ambition, although lacking the capability to take on the task.

The task eventually fell to Junkers, a state owned (nationalised) business, that would do what it was told. Not withstanding there status, had maintained a high degree of competence. On that basis they received the task.

Above is the in-house Messerschmitt D a development of a the C, which lacked a conventional UC, although lengthened.

In the case of Junkers, it appears they quickly came to the conclusion, that the whole thing needed a good look at, with a view to remove all the unnecessary features and to productionise the aircraft. Gone was the blended body wing roots of Lippisch. Instead we could be looking at the Bell X1 of future years, in that the cross section of the body is circular from nose to tail as far as is practical and symmetrical.

To what extent either the 247 as Junkers called their version and the 163D were flown is apparently contentious. All I can say, there are very strong indicators that the 247/263 flew, as here are pictures of the aircraft covered with wool tufts. A number of pilots have been identified as having flown them, although under what circumstances is uncertain. I would expect that there are some good records in the UK and the USA as they hovered up what data was available on such projects and aircraft.

[Colin Leighfield]

This is right up my street Erfolg, a shared interest.

[Erfolg]

Although I am not into scale models, as defined by many scale modellers such as Danny Fenton, where absolute outline and surface detail is everything. I do build my idea of a scale model, which should look right, at a glance from 10 meteres away and be robust enough to fly most flying sessions. There is another proviso, I must not have invested so much time that i am traumatised when it crashes. On that basis, the Cutlass that was a recent free plan fails, the reason being that the side pods, forming the inlet and housing for the engines fails.

To get the feel I have used the images and drawings in the book, plus other sources to get an understanding of how it was designed.

The above drawing is a table for the CG and weight calculations and design management. Importantly shows the centre line and other features which helps in that understanding.

I then scanned a drawing

Which i related to the wings I have obtained from Cloud.

The advantage of these wings although not 100% scale in all respects are pretty good. Come complete with all the bits to build them, including the servo boxes. Cloud do make wings to order, I had considered ordering a set in the region of 52" span, in the end just went for the stock wings.

Rather than draw out the full size model, I have decided, to treat the build just as in industry. That is use the dimensions from the sketch, saving some work.

The first stage has been to mark out the body as blanks then cut out blanks as the first stage.

I will join the two halves temporarily. Then I will be fitting a shorting plug to my fw 190A, so that I can cover it with tissue, The intention is to keep the two ticking over side by side.

I have asked for advice for a suitable inrunner, as yet I am undecided on which to get. To help decide I will weigh my Cloud Komet, to help in deciding how many watts to go for. Although I cannot but note that the high revs small propeller, does not accelerate the model as effectively as a large prop. Yet the small size and being near the ground , limit the prop to about 6" diameter, and a 4" pitch provides a decent top speed when rotating at 20,000 rev min-1.

[Keith Simmons]

Hi Erfolg, Your sketch looks like the Me 263 from page 38 of Luftwaffe, Secret Jets of the Third Reich. I am surprised that the Komet took years to design and he learnt as he got along, that the design started in 1921 & the design took off in 1930's as a rocket plane due to the fact that after First World War, Construction of aero engines was forbidden in Germany.

Oh dear..  It says Me263 in the title.  

Edited By Keith Simmons on 09/10/2015 16:40:11

Edited By Keith Simmons on 09/10/2015 16:42:01

[Erfolg]

The wings were all the same(from the B onwards), irrespective of the version.

Although the data indicates differing spans, I think this is just variation in the wing pick up points, and that the 247/263 had a slimmer body, which pulled the pick up points in a little.

In many respects the project could not even be conceived, without the input from Walter, yet Walter could not conceive of a motor until the need was identified.

All the messing about with solid fuel rockets, were really as much about raising the profile of the rockets and Opel, rather than the serious use of rockets as a propulsion method. Although I do think that all involved hoped there was some promise from solid rockets.

[Erfolg]

Still trying to make progress on two fronts.

I had hoped to be tissueing my 190A, and just made very little progress.

I have however made some progress on the 263, in this case i have been working on the blank for the body.

The first stage has been to join two 50 mm Blue Foam blocks together and mark out the stations for the various diameters

It has been during this process that I discovered that it does appear that Cloud have compromised a little, or the references to a slimmer 263 body are not true. It appears that there is a discrepancy of approx 30mm dia between the 263 and the 163 with the 263 being the larger diameter.

When I start the contouring process, I will also compromise, rather than stick to the 130 mm dia. i will probably bring the diameter nearer to the 100 mm dia. After all this is not a true scale model, just squintish scale.

I have selected and ordered a motor, which if unsatisfactory will be swapped out. The principal reason for selection is that it will take 500 watts on a 3s. The downside is that the motor is heavy. The plus side is that i have used the 480 low Kv version on two models, both have ample power (Sagitta 2m and the TH Clean Sweep). There is another issue to be wary of, in that the screw on end plates can unscrew, if insufficient cooling is provided.

[Erfolg]

Although not overly concerned, I have been bothered at the apparent discrepancy between the Cloud 163 body dia and the apparent diameter when scaling from a scanned drawing of the 263.

I compared the span of the 163B, 163C and the 263D, from published data. A number od sources stated the same thing, the wings were common to all, as was the rudder/fin. From this i conclude that the 263 was of smaller body size, as the span is lower, although it is not much.

I have come to the conclusion, that the use of relatively small drawings, can result in errors. Even small errors made by the draughtsman will be magnified when scaled up. In my case 1 mm leads to something close to a 5mm error. That is without considering errors in the scanning process, my measurements and my maths, From this if it looks OK, I will be happy. I guess even Cloud may not be spot on either, although it looks good.

Whilst doing some reading it is apparent that the B and D are essentially perfectly round cross sections. Although in the case of the B, the need for a skid and other junk, has appendages attached to both the top and bottom of the fuselage. In the case of the 263, it retained the circular cross section. The other major change is the lack of large root fillets on the 263. It is apparent that the 263 was extensively tested in the wind tunnel. I can only assume that the improved fineness ratio and the longer nose entry, made the need for fillets redundant. There is one reference that suggests that the 263 was taken to mach 0.8, which was the same critical limit for the 163B.

Edited By Erfolg on 14/10/2015 20:21:32

[Colin Leighfield]

Erfolg, I think your assumptions are correct, certainly I had assumed the basic fuselage cross section to be circular.

Not sure about the explanation for the wing fillet difference, perhaps you're right. I think I've read that approaching the critical Mach no. the 163 began to tuck under. If it did that you'd probably be lucky to pull out, I expect. I bet you wouldn't have very long to find out.

[Keith Simmons]

Hi Elfolg, what do you mean the span was lower? Would it mean the span wise of the wings themselves the same as 163 & 263 & therefore the fuselage smaller in dia?

I would have thought it's the other way round so to enable the wheels to retract into the fuselage, they just lengthen the fuselage to accommodate the wheels?.

Is the Komet pitch sensitive?, maybe the 263 even more so.

Just as well the Komet has not got the rapid firing cannon to match the high closing speed to the allied bomber fleets.

Edited By Keith Simmons on 15/10/2015 10:10:03

[Erfolg]

Keith

Yes the diameter was fractionally smaller.

The redesign by both Messerschmitt with the C version was to address the duration issue, which then moved into the D version to address the ground handling issues. The Junkers 248 was an attempt to address both issues without the constraints that the piece meal initial approach.

As to pitch sensitivity, I cannot say it is as the Cloud model, some experience with flying wing gliders, seems to suggest that this is not an issue. My observation with flying wing gliders seems to indicate that stall, results in a nodding model, rather than a stall as is the case with a std. type model. I would imagine that slope flyers, where flying wings are not uncommon, will have a broader understanding than I have.

With respect to the Cloud 163, my model CG was set up exactly as specified. With also exactly the specified reflex.

I did not rely on my std pin type CG balancer, as it seemed not as sensitive, as hanging the model up.

I am not sure about the effects of inertia will be as the motor moves forward, although, again with my gliders there was no inertial issues obvious.

Perhaps one aspect with one glider that did surprise me was moving the CG rearward, resulted in flat spins , this occurred when flying slow and banging on full power. The model would just land as a leave, no control inputs. power on or off had any effect. It just spun, flat, like a Frisbee, totally undamaged.

[Erfolg]

I have made a little progress today, sanding the blanks into a rough form.

I will put these to one side for now, as a priority, as my attention switches to covering my Balsacraft 190A. However, that will not mean a halt, rather that the 263 becomes the fill in job, when I am waiting for something on the 190.

Not having a plan as such, I probably spend more time proportionably thinking about what to do and then in what sequence.

[Erfolg]

I have started the assembly of the Cloud wing kit.

Essentially it is now nearing the first stage build. I have attached the LE. TE, attached the tips, sanded to basic contours, cut out the servo pockets and trimmed the pockets and the covers, and bored the servo lead, lead outs. A lot has been done, all because the Cloud kit has done an awful lot for you.

I have received the motor and hope to start the installation process for this item tomorrow evening.

I can then complete the final sanding of the body.

[Erfolg]

I have now reached the point where everything becomes a little bitty.

The bit I have been working on is the motor mount. This can be a little critical as the mount could well be seeing something approaching 400w.

The mount is mainly ply, that should be all ply. The motor although billed as being more efficient than an inrunner, generates some heat. From previous experience with the larger version of this motor, the screw end cap can unscrew, if not kept coolish. Previously I have managed to burn out an inrunner that was totally uncooled. In this case as the previous i have tried to undue the end-cap, so that I can use Lock Thread on it. Just as my previous other recent purchase i could not get it undone. The other approach is the obvious and that is to provide some cooling. There motor has inlets at the front and cooling outlets to the front and sides. With a built in fan to assist in cooling.

The next job was to bore out the body to take the motor mount. I initially tried a tank cutter of the correct size, which would not run and cut true. I therefore used an under size tank cutter and then sanded to size.

There is just enough meat on the mounting flange to permit some sanding to contour.

The next stage requires the body to be marked out for the wing, then cut . This will then permit, the interior to be cored out. How much will be an issue. This is an area where I do think that Cyril Carr could guide us all, or at least me, a few photos of his approach and experiences would be incredibly useful. For that matter anyone elses experiences would be educational. I have seen an indoor FF scale model done using the same basic materials. The trouble with this example was that the wall was only perhaps a millimetre thick. But these models never see the punishment and abuse that my models see, flying in all weathers and guided with less than the proficiency of an expert, or that should be an average flier.

This has been a useful distraction whilst i wait for the dope to fully dry out on the Fw prior to the first sanding.

[mightypeesh]

Hi Erfolg, good to see it coming on - I recently got a copy of Luftwaffe, Secret Jets of the Third Reich, and must say that there are so many good looking possibilitys for builds within. I too was dissapointed by Cyrils plan - but definately have one on my build list. I was going to knock one up next but I have nearly finished the drawings for my little Dr1 which had managed to bump up the queue somehow! Keep it going,

Cheers, Simon

[Erfolg]

Hi Mightypeesh

I hold the booklet in quite high regard, principally on the basis that it has put many of the German WW2 secret aircraft into perspective. The vast majority were tender proposals, rather than substantial bodies of work, that were stopped by circumstances. Rather than the reality of not receiving a contract.

The remaining real aircraft also has in some cases a better insight as to their early period of gestation, in addition to some new photographs.

If the same approach to secret British aircraft were to be taken, there would be a wide variety of some pretty impressive ideas. In the case of the UK all these proposals are by and large residing in the bottom of drawing cabinets and filing cabinets. Occasionally a outline sketch appears in the back of a book or mag, without the procurement details etc.

The short of it, the vast majority of secret German WW2 aircraft, were simply contract tender documents, which were rejected. Although some of the proposals were nearer to being a reality than most.

With respect to the CC plan, it was an opportunity missed. A really good piece could have been written, outlining the various stages of producing a body, in addition to the techniques used forming the body. A little more detail on how to cover with Brown Paper would also be of great interest (at least to me).

With respect to brown Paper technique Tony Bennet has provided some useful methods as being applied to his Trent Meteor.

In my case I am always looking for feed back on how to do many things. In this case it is using blue foam. My approach has been to progress in the same way that people did with Static Solid Models, that is to create a blank. Mark out all the profiles. Cut to the profile lines. I produce a set of templates for measuring the fine curves. Then to shape. My tools are cross cut saw and sanding block.

I know that this is not the only way. Cyril C uses a hot wire cutter. Although I a have know idea of how he forms the contours for the fine shape.

There will be many others who have there own approaches and techniques. I personally would be very interested in the alternatives and their advantages and disadvantages. Perhaps another RCM&E article, on the use of foam, cutting techniques with how to do it (with respect to the hot wire technigues in particular).

[ron evans]

Hi Erfolg

My last Cutlass had a blue foam fuz and followed the same route as yours in shaping. My blank was made up of two pieces spot glued together on the side view centerline, then split after shaping. Internally I made the cutouts with piano wire shaped and set in a wooden file handle then heated on the gas stove, followed by making the wing cutouts then the whole thing was glued back together with the wing in situ

If you use a hot wire on blue foam do it outside, the fumes are deadly

I finished mine with glass cloth and Wilkos poly, but it didn't make it very ding proof, so next time I'll try brown paper.

I have a pic somewhere of the bare fuz but it probably wouldn't tell you much.

Ron

[Erfolg]

Ron we seem to be following a similar set of ideas.

I have lightly tacked the two halves of my fuz, to aid splitting for further work. In my case along the horizontal axis or the "x" axis, as this will be more convenient.

It is my intention to cover the body with lightweight glass cloth also.

In my case I will probably use Ronseal Diamond Hard, as I have it and I have used it before on other models. I have used Wilks WBV previously which is slightly softer than the Ronseal stuff. I first used a trade product used by contract floorers, which was rock hard, far to difficult to sensibly sand, had some Japanese sounding name. I would use it again, but is not the best for modelling, as with flexing, stress cracks.

Now the idea of the hot wire sounds attractive. I have Dremeled the interior out previously with the drum wheel. It is dusty, prone to local overheating and forming a very hard skin, which is a slight problem if further work is intended. So I will give the hot wire a try.

[ron evans]

Erfolg I've found the pic......watch those fumes I've also found that Wilko poly to be more flexible, and it works well wih glass on an EPP fuz with no cracking on the squashy foam.

Edited By ron evans on 22/10/2015 15:34:48

Edited By ron evans on 22/10/2015 15:36:37

[Erfolg]

Ron

First things first.

That is a very nice looking model, which demonstrates the usefulness of Blue Foam.

Is it the model that NH Cutlass is based upon.

Is the wing built up or a solid carved wing?

I am at present Dremeling the unwanted material out at present as the weather up here in "The Great Northern Powerhouse" is not great.

I am now starting on the canopy plug as it is quite large and potentially, never mind potentially, it will influence the location and size of the hatch or may be hatches.

[ron evans]

Hi Erfolg

Yes I designed the original Cartoon Cutlass, the first one, based on the -1 prototype was done with an EPP fuz and floormate wing ( like depron ) with a KF wing section, all covered in glass & poly. The second one above based on the -3 with the big canopy has a blue foam fuz and flat 6mm balsa wing just to see the difference.

Nigel H asked me to send him the plans after seeing the pics. He wasn't keen on using foam so redrew it with a balsa fuz.To be fair to Nigel he did the lions share of the work to get it into print, and without him it would not have happened, ( I miss his column ).

I've had a bit of stick for not adding the motor side cheeks ,and I fully intended to do them on the second one ( see wing LE at root cut ready ) but impatiens got the better of me...other people have done it and it does look better and seems not to effect the flying bit. If you click on my photos there are more pics of them both.

Looking at your motor installation it looks very snug, will you have cooling airflow from the motor through the fuz and out of the rocket pipe at the back.

 

Edited By ron evans on 24/10/2015 16:20:18

[ron evans]

Impatiens should have read impatience

[Erfolg]

Now having finished the Balsacraft models, I am now in a position to continue finishing this model prior to moving house, when a date is given.

Before the demise of HK Firenza, it became abundantly clear that foams when subjected to loads have a tendency to be compressed and distorted. I have also noted that the PZ Albatross and Reliant that I have do not seem to suffer from the gross distortion of the Firenza. The PZ models have been flown and landed many, many times more frequently than the Firenza, the difference is not the materials of construction both being EPO type materials, more how the forces and resulting stresses and strains are dissipated. This model has a problem in that the material is Extruded Polystyrene, which has pretty poor characteristics compared to EPO.

Taking this into consideration, i decided that a frame is required to act as both a backbone and a means of dissipating some of the forces into the foam.

The pictures above show the frame with the UC components, then the lower body with the slot for the frame.

The next picture is of the model with frame inserted and glued into position. In this case i have used polyurethane glue, the brand is Gorilla. It is perhaps worth mentioning a little about the product. In functional performance it is no better or worse than any of the much cheaper brands. On this basis it is extremely poor value for money. However there is one very important characteristic that can be very important, that is shelf life. In this case i have now had the bottle in use for 3 years, it is still just usable, now reaching the point where it should be binned, although it does seem i will have used it up prior to this point. All in all the high cost can be justified as many of the rivals will have been binned having gone of after about 6 months.

I feel i am now starting to get somewhere.

The next stage is to get the nose wheel mounted.

Having done this, I can consider where and how much material is to be removed internally for the Lipo, to obtain the correct CG. This is important with such a small model, as any significant amount of lead could totally kill the model as a practical pleasant to fly model. Although the motor is able to deliver up to 500 watts, a sensibly sized Lipo to provide bot the current and any duration would probably be unacceptable. It literally would be a case of climb to height, run out of power and glide back, dead stick.