United and AA to start booking flights at full capacity

American and United airlines are going back to allowing passengers in middle seats, despite the nationwide increase in COVID-19 cases.

United has already started this practice, but American Airlines will begin opening all seats on Wednesday.

OF COVID-19 CASES.ABC'S GIO BENITEZ HAS THEDETAILS IN TODAY'S GMA FIRSTLOOK.AND NOW, TWO OF AMERICA'SBIGGEST AIRLINES ARE LOOSENINGSOCIAL DISTANCING RESTRICTIONS.AMERICAN AND UNITED TELLING ABCNEWS ALL SEATS - INCLUDINGMIDDLE ONES - ARE UP FOR SALE.SOMETHING UNITED HAS ALREADYBEEN DOING, AMERICAN WILL OPENUP THOSE SEATS WEDNESDAY.SO, IS FLYING ON A PLANE SAFE?JOSEPH ALLEN, HARVARD T.H.CHAN SCHOOL OF PUBLIC HEALTH:"IT'S A RISK LIKE ANYTHING.I THINK THERE'S A COUPLE OFTHINGS YOU HAVE TO ASK YOURSELFBEFORE YOU FLY.ONE - IS IT NECESSARY?

DO YOUREALLY NEED TO TAKE THAT TRIPTOO?

TWO - DO YOU HAVE ANYPERSONAL RISK FACTORS THATWOULD PUT YOU AT GREATER RISKFOR COVID 19?

AND COMING UP AT7AM, DR.JEN ASHTON WEIGHS IN LIVE WITHWHAT YOU NEED TO KNOW BEFOREBOARDING A PLANE - WITH YOURGMA FIRST LOOK, I'M GIOBENITEZ, ABC NEWS, NEW YORK.MEANWHILE-- STARTINGTHURSDAY - LAS VEGASBASED ALLEGIANT AIR - WILLSTART REQUIRING FACE MASKS