There's something Bellanca Viking 'ish' about the fin.
There's a good reason for that Mechta
.
The challenge was indeed based on the Bellanca 17-30 Viking 300, using the same tail, wings, engine as its host. Must admit I thought the fin being so distinctive would give it away once I had said it was based on a production aircraft.
Now the awkward bit....Mechta has posted the drawing of the challenge aircraft but actually hasn't identified it! But unless anyone disagrees, as he's done all the hard work he should be awarded the challenge. So for sake of good order the aircraft is the Bellanca M300, a lightweight counter insurgency aircraft which was proposed by the manfacturer in the 1970's, fitted with machine guns and able to carry rockets and bombs! Would have packed quite a punch for such a small plane.
Mechta has declared Open House.
Ps...hope the revision goes well Mechta
Edit to say:
Morning RD
"cannot be that simple a answer"
Thats the fun of putting up an aircraft from a well known manufacturer!