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Well, Zdenik Drbal from Czech Republic contacted me to say, "The yellow model with the sign OK-ARJ is of the Czech agriculture plane Z-37 "Cmelak" ("Bumble Bee").

He goes on to say that it is a one-seater, compact, low-wing plane of all-metallic construction. It has an all-metal wing with very effective flaps and "unmoved slot" (I'm not quite sure what Zdenek means, there). The fuselage is constructed from steel tubes and it is covered with a special chemical-resistant material. The 700-litre tank for chemicals is located at the back of the cockpit. Gear is classical. The standard colour of the plane was yellow with red trim and black markings.

Specification: Wingspan - 12·22 meters Lengh - 8·25 meters Mass of empty plane - 985 kilograms Engine - M-462 RF Power - 232 kW Ceiling - 4040 meters Range - 640 kilometers

Zdenik's model

Meet Zdenik on personal profiles

Geoff Graham comes up with the answer, not in the form of a plan but clear instructions and good pictures that serve equally well. These thumbnails are giant size so you can see enough detail here, but click on each one for an even closer look. 

This stand is very simple to make and has the advantage that it folds practically flat taking up very little space in my tiny Puma car.  The universal top will adjust, as do many stands, simply by swivelling the two sets of prongs to grip various fuselage widths. 
 

The stand is made up from 2"x1" planed timber from a builders' merchant with one short piece of 3"x1" for the top.  The most difficult thing to achieve for the less-skilled woodworker is planing a face on the one edge of that top section as it has to be glued on to one of the sets of legs presenting at more or less than 90 deg (depending on which way you view the joint).  The hinges are then attached to the opposite edge carrying the folding half. The easiest way to achieve accuracy would be to use a bench sander with angled fence but I don't have one.  I therefore have to master the skill required and after nearly 50 years of practice I am getting there.

4 shows the angle I mentioned.  The top piece must be planed to give the angle between the fixed side and top.  It can be pulled up using screws and glue - no need for cabinet work here!  Pic 5 shows the hinges.  6 shows the dowel holes and the captive thread.  7 shows typical top revealing the very simple method of construction.  This uses MDF, butt jointed and with a simple square piece of timber in the right angle between the base and the ends for strength.

 

Using a couple of 9mm dowels there is need for only one, central, fixing bolt and that of course goes down into the captive thread.  The stand is very convenient on the field being easily customised for each model.  Furthermore, if you need to anchor the whole thing say for an engine run, you can lay some heavy item across the base of the A-frame legs - or even use a screw-in ground spike plus luggage elastic for same purpose.  This saves the old back a deal of suffering and keeps the ageing knees dry!!

Should you have aircraft which have strange shapes or are "upside down" then a special top can be quickly made up from MDF or ply.  The DH71 is such an aircraft as the servos are only accessible from below in the wing bay being, as they are, mounted upside down.  The radio and battery are also in this bay making it essential to be able to securely hold the aircraft upside down for that access.  Having connected the aileron leads the wing can then be rigged.  As this particular model has a pronounced engine and streamlining fairing running right along the top of the fuselage it was also necessary to be able accommodate that safely and securely.  Hence the odd shape of the rests seen on this DH71 stand top.

Thanks for that, Geoff.

I must admit that when Ashir asked the question, I immediately thought of Geoff as an almost certain source of the answer!