History

The MD-87 is a slightly shortened MD-80, allowing airlines to take advantage of the MD-80's aerodynamics and engines without excess capacity. It also introduced the “glass cockpit” to the MD-80 family (which was subsequently offered in the original-length MD-83). The MD-90 is the longest of the family, approaching the original DC-8 in length. These kits are nearly identical, the differences being the fuselage length and engines. In each case the construction will be the same.


First impressions
Details are very crisp and the execution is clean. The kit makes good use of the strengths of resin and vacuform moulding techniques while avoiding the major weakness of an all resin kit which is its comparatively heavy weight. Since the MD-90's detail parts are identical to those of the MD-87, I've taken pictures only of the fuselage and engines. For all other parts refer to the MD-87 pictures

Fuselage
The fuselage is in Welsh's traditional thick vacuform plastic with 3 bulkheads to keep it from collapsing. Windows are provided as decals with a note on the instruction sheet advising the modeller to apply the decals as a guide for marking their positions preparatory to drilling them out if clear windows are desired. Nose weight will be required. In addition to the bulkheads, small tabs cut from the backing sheet should be glued to the fuselage halves to help keep then aligned and to add to the gluing surface. Give them a little curl before gluing to keep the fuselage circular. Welsh have captured the double bubble cross section and the windscreen area faceting but the latter could be a little sharper.


Wings
Each wing is a one piece resin moulding. The flap actuator fairings and vortilons are separate metal parts, some of which are quite small and prone to disappearing into the lair of the carpet monster. Being resin and metal, they will need to be glued with epoxy or cyanoacrylate glue. The wings are a butt joint, and will definitely require drilling and pinning.


Empennage
The tailplanes are one piece resin mouldings. They will need to be drilled and pinned for strength. Since many MD-87/90 liveries cover the entire fin, the tailplanes should be left off until after painting and decalling is complete. The DC-9 family's elevators are controlled by servo-tabs and not interconnected so it is quite common to see them deflected at different angles while the aircraft is not flying: http://www.airliners.net/photo/Aserca-Airlines/McDonnell-Douglas-DC-9-32/1927352/L/

Engines
The engines are in 2 pieces including the pylon. The casting plugs will need to be removed before assembly. Check to make sure your livery's cheatlines will fit around the pylon. If it won't, you'll either need to apply the decal first, then glue the pylon and clean up the joint or perform major surgery to your decal to make it fit around the pylon. The pylons are fairly thin, but they could be carefully drilled for pins.

Landing gear
The landing gear struts and wheels are white metal. The gear doors are also metal, and are thinner than plastic, but still a little thick. They'll look good regardless.

Accuracy
I don't compare models to drawings or published measurements. When assembled it looks like an MD-87/90

Decals and markings
The MD-87's decal sheet has markings for one of Reno Air's aircraft that was operated by American Airlines after their merger. The fuselage was left white in contrast to America's usual polished metal. The instructions call for overall white, but photos on airliners.net show that the lower fuselage and tail are grey. All necessary markings are present on the sheet, but there are few stencils. The MD-90 offers a choice between Delta's Classic “widget”, or the later “beach towel” that lasted for only a year or so. The MD-90 sheet was printed by Two Six decals while the MD-87 sheet is nameless but appears to have been printed on a laser printer. The artwork looks very thin on the sheet and should definitely be applied to a white background. It likely should also be coated before application.


Conclusion
These kits illustrate the strengths of the vac/resin combination. They're simple, very well detailed and the subjects are ones the mainstream manufacturers will never even dream of producing. They could very easily serve as an intermediate kit to a modeller who has limited vacuform and multimedia experience. Welsh Models assume that the modeller has had sufficient modelling experience not to need detailed build instructions. In most cases their instruction sheets consist of 1/144 drawings of the aircraft with detail notes describing items to pay attention to during the build.