flat car ??

[union pacific 844]

what is the longest  flat car made  for ho scale?

[Jerrys HO]

Model Train Stuff has an extensive stock of various sizes.

http://www.modeltrainstuff.com/HO-Scale-Flat-Cars-s/1492.htm

[jward]

somebody made models of the standard 89' intermodal flat from the 1970s. those were about the longest standard cars made, anything longer on the real thing was a piece of specialty equipment with multiple trucks (schnabel cars, depressed flats, etc)

the 89' standard flat has also been used as a base for autoracks.

[sd24b]

what is the longest  flat car made  for ho scale?

89'4" Walthers, Atlas and Athearn.  your choice of channel or all purpose.