A Southwest Airlines pilot who cops say failed multiple field sobriety tests minutes before he was supposed to fly is denying doing so … despite being arrested on the jet bridge.

David Allsop — a 52-year-old pilot that’s been flying with Southwest for 20 years — tells TMZ in a statement through his attorney David Chaiken that the body cam video of his arrest shows the “obvious” — that he committed no crime.

He also claims “experts” have reviewed the footage and determined officers implementing the field sobriety tests did so without following “proper procedures.” He adds … “These procedures are in place for a reason, to prevent mistakes like this one.”

You can see in the bodycam video we published that Allsop admitted to police he had 3 Miller Lights before the flight, but said they were consumed 10 hours before the incident.

When the officer mentioned he smelled something consistent with alcohol, Allsop blamed it on his nicotine pouches.

Anyway … the pilot ended up being arrested and did not get in the cockpit of the plane.