The wrongful termination lawsuit filed by an Allegiant Air pilot fired for making an emergency landing at St. Pete-Clearwater International Airport in 2015 has turned into a bitterly contested match as it marches toward a July 31 trial date in Nevada.

The legal battle includes accusations of documents withheld in discovery, questions about the memory of the airline's CEO and a request for a battery of personality tests of the pilot, which a judge denied.

The Las Vegas-based airline has forced the testimony of pilot Jason Kinzer's 76-year-old mother even as Allegiant CEO Maurice J. Gallagher Jr. has so far fought successfully to prevent his own testimony, arguing he knows nothing of relevance about Kinzer's firing.

That led Kinzer's attorneys to argue recently in a motion, "Mr. Gallagher's purported total amnesia is facially improbable."

Case in point, they argue: flight attendant Natalee Negron's impassioned email to Gallagher shortly after she learned Kinzer had been dismissed.

"I feel as though safety definitely was the deciding factor to evacuate that day," Negron, who was on the flight, told Gallagher in the email. "But I honestly just felt a need to express that a Captain that had safety in the front of his mind is no longer with the Company. I truly hope that this decision was made with the utmost caution and consideration of the facts."

Gallagher forwarded the email to his chief operating officer and vice president of in-flight services with a note: "please talk to me."

The airline's chief said in court papers he has no memory of Negron's email nor of forwarding it to several of his top deputies. And defense attorneys say the airline withheld the email during discovery in the case until recent weeks. That is a claim denied by Allegiant.

For a case that hinges on Kinzer's decision-making, the flight attendant's defense of the pilot could prove critical at trial.

Kinzer, a former St. Petersburg resident who was then 43, was flying Flight 864 that departed the Pinellas County airport with 141 passengers on June 8, 2015, bound for Hagerstown, Md., when flight attendants reported an acrid odor in the cabin not long after takeoff. The pilot declared an emergency and returned to the airport.

Previous coverage: Suit says Allegiant improperly fired pilot who evacuated plane after emergency landing

Kinzer and his co-pilot were told by someone in airport fire rescue upon landing, "I'm showing smoke on the No. 1 engine."

But a recording of radio communications reflected confusion on the ground with rescue personnel who did not immediately answer questions from the cockpit, something Kinzer said late played into his decision to evacuate.

Evacuation chutes were deployed. Eight people suffered minor injuries in the evacuation, the most-serious injury being a broken wrist.

The landing generated considerable media attention, and Allegiant officials later fired Kinzer after saying there was nothing wrong with the plane and the evacuation was unnecessary. The Allegiant pilots union said the firing was about Allegiant management sending a warning that the company would not brook being embarrassed during contentious negotiations for a contract then underway.

It also was one in a series of emergency landings in 2015 and after that caused concerns about the budget airline's safety record.

Previous coverage: Thousands of people flew Allegiant last year thinking their planes wouldn't fail in the air

Allegiant officials and Kinzer's attorney said they could not comment on pending litigation.

Negron, who also could not be reached to comment, told Gallagher in an Aug. 10, 2015 email that Kinzer's dismissal "has been weighing heavily on me."

An Allegiant employee for more than seven years when she wrote the message, Negron had served as a stations corporate instructor and said she loved working at Allegiant. "I've been nothing but grateful for this company," she said.

But she told Gallagher bluntly, "I just feel this undying urge to reach out to you on the topic of what I feel to be the wrongful termination of a Captain."

"All other parties that were involved that day were returned to duty with no additional training, which makes me wonder what the Captain did that was so wrong he received the harshest punishment, especially hearing from Flight Ops management that the evacuation went as trained," her email said.

Negron blamed miscommunication by rescue personnel on the ground for confusion that led to the evacuation.

"I truly hope I'm not stepping out of place with this email," she concluded. "Forgive me if I can."

Contact William R. Levesque at levesque@tampabay.com. Follow @Times_Levesque.