A two-seat agricultural version was later known as the Ag-5.

The 998 is available in both single-seat and two-seat versions.

Unlike many other early jet fighters, no two-seat version was ever produced.

A two-seat version called the Bullet was also built.

A two-seat version was also marketed by the company.

The maiden flight of the L-159 occurred on 4 August 1997 with a two-seat version.

Plans were available for both single-seat and two-seat versions, but only four were constructed.

The blocks cover both single- and two-seat versions.

A two-seat version the Model EC-2 was also developed.