Now we are back to your understanding of large numbers. Yes you are more likely to have a false negative but false positives are still a significant problem. Again if you test 10,000 asymptomatic pilots and one percent are false positive you just sat 100 pilots out for a few days at least. Yes you will have a second test but that will not be at the gate as that would just produce two opposite results from an unreliable test. You will have to have PCR testing and wait for those results for 24 to 48 hours. Most employers will not take the chance and require you to quarantine even after a negative PCR.

From the CDC website:

Not everyone needs to be tested.

Who should get tested

• People who have symptoms of COVID-19.
• People who have had close contact (within 6 feet of an infected person for a cumulative total of 15 minutes or more over a 24-hour period) with someone with confirmed COVID-19.​​
• People who have taken part in activities that put them at higher risk for COVID-19 because they cannot socially distance as needed, such as travel, attending large social or mass gatherings, or being in crowded indoor settings.
• People who have been asked or referred to get testing by their healthcare provider, localexternal icon or state health department.

If you do get tested or take an at-home test because you have COVID-19 symptoms or have had a close contact with someone who has it, you should self-quarantine at home pending test results and follow the advice of your healthcare provider or a public health professional.