You will be asked if you have failed any training events...you can tell them anything you like. However the federal Pilot Records Improvement Act (PRIA) was established a number of years ago to help catch marginal pilots who would hop from job to job to escape training failures. You will be required to submit PRIA paperwork which will go to your previous employer, who will be required to forward all of your training records to your new employer.

This paperwork will normally be completed after you have started ground school, at which time you will be immediately fired for lying about your background. This information will be available via PRIA to the NEXT airline you apply to...of course no airline will ever hire you after getting caught lying about your background.

The airline business has zero tolerance for integrity malfunctions, and I do mean ZERO.

Since your training record will follow you for life, most pilots take training seriously. Don't attempt 121 training lightly...better to CFI for 6-12 months and/or get some imstrument experience if you're not 100% sure of your abilities in a light piston.