Identify by airplane characteristics

The Merlin III is the short body version of the Metroliner commuter aircraft. It has the same nose, undercarriage, tail and engine nacelles, but larger cabin windows. 

The key features of the Metroliner commuter aircraft are the long fuselage with long nose and horizontal stabilisers attached to the dorsal fin. There is als a short body Merlin version, which has larger cabin windows.

The configuration of the SJ30 is pretty standard with a low-mounted wing, engines attached to the fuselage and a T-tail. Unusual, however, are the legs of the main landing gear, which look somewhat like those of a Jaguar fighter. Also look at the leading edge of the vertical stabiliser, curved al the way to the trailing edge.

This turboprop trainer has a stubby appearance, a tail like the PC-9M (so with a large dorsal fin), a two piece canopy, wings with continuous dihedral and on most versions small winglets. 

Compared to similar aircraft the Taylor­craft 20 stands out due to the long struts in triangle shape, attached to the wings at nearly two thirds of the span. The triangular horizontal stabilisers with rounded tips have a single strut. The wing tips are only slightly rounded. The aircraft has a horizontally opposed piston engine.

The main British light observation aircraft from the 1940s has a fabric covered tube airframe that is wide at the front and narrows towards the tail. It is normally powered by an inline engine with the pistons at the bottom.

The Rysachok looks a bit like a cross-over between an Ae270 and a Rockwell Commander 700. The engine intakes on top of the nacelle, the large single main gear wheels and the large square cabin windows make it distinctive from the rest.

This modern Russian DHC-2 look-a-like can have a radial piston or turboprop engine. The SM92 has three large cabin windows and a cruciform tail with strut braced horizontal stabilisers.

This light twin prop aircraft has high mounted wings with tall winglets as main characteristic. Additionally, it has a retractable gear, a high top edge of the front cockpit window and curved top of the fuselage, seen from the side from nose to tail. 

The P2012 is a ten seat aircraft with an all single wheel fixed gear, of which the main gear is attached to the fuselage. Typical are the cabin windows with 'race track' shape, so ovals with straight sides. The wing tips are slightly bent up. (photo by Marco Papa, used with permission)